Dr. Padmanaban R. currently serves as Assistant Professor (S. G.) at Department of Mechanical Engineering, School of Engineering, Coimbatore Campus. Handling subjects for undergraduate and postgraduate students, inspiring and motivating them to achieve personal and academic success. Specializing in the application of computational methods for analysis of manufacturing processes, aiming to understand and improve the process.

Education

  • Ph.D.,2013, Faculty of Mechanical Engineering, Anna University, Chennai (PSG College of Technology, Coimbatore), Tamilnadu.                                                 
  • M. E., Mechanical Engineering (Engineering Design), 2002, Government college of Technology, Coimbatore, Tamilnadu.
  • B. E., Mechanical Engineering,1999, Tamilnadu College of Engineering, Coimbatore, Tamilnadu.                                        
  • Schooling: Perks Matriculation Higher Secondary School, Coimbatore, Tamilnadu.

Work Experience

Year Affiliation
August 2013 to Present Assistant Professor (S. G.), Department of Mechanical Engineering, Amrita Vishwa Vidyapeetham – Coimbatore, Tamil Nadu
June 2009 – July 2013 Assistant Professor (Sr. Gr.), Department of Mechanical Engineering, Amrita Vishwa Vidyapeetham – Coimbatore, Tamil Nadu
July 2006 – May 2009 Senior Lecturer, Department of Mechanical Engineering, Amrita Vishwa Vidyapeetham – Coimbatore, Tamil Nadu
October 1, 2004 – June 2006 Lecturer, Department of Mechanical Engineering, Amrita Vishwa Vidyapeetham, Coimbatore 
June 2002- September 31, 2004 Lecturer, Department of Mechanical Engineering, Karpagam College of Engineering, Coimbatore

Thrust Area of Research

  • Welding and Material Processing

Awards and Achievements

  • GATE 2000 Score - 76.57 Percentile
  • Awarded Best Teacher award for producing 100% results in the subject Computer aided engineering at Karpagam college of Engineering in 2003 university exams.

Teaching/Research Interests

Major Subjects Taught

  • Engineering Mechanics
  • Finite Element Method
  • Fracture Mechanics
  • Random processes and partial differential equations

Research Interests

  • Solid state welding and processing of lightweight materials.
  • Numerical Simulation of welding and other manufacturing processes.
  • Design of Experiments, Optimization, and Soft computing

Computer Skills

  • Microsoft Office – Word, Excel, PowerPoint, OneNote.
  • Proficient in using ANSYS, ABAQUS, MINITAB, MATLAB  and PYTHON Programming.

Publications

Publication Type: Journal Article

Year of Publication Title

2021

Vaira Vignesh R., R. Kumar, A., Srirangarajalu, N., and Dr. Padmanaban R., “Investigations on the Mechanical, Corrosion, and Tribological Behavior of Friction Stir Welded Aluminum Alloy AA8011”, Transactions on Maritime Science (Accepted) , 2021.

2020

A. Joe Alex, Dr. Padmanaban R., and Dr. Govindaraj M., “Effect of Fe particles on the microstructural evolution and mechanical properties of friction welded Al-Cu components”, Australian Journal of Mechanical Engineering, pp. 1–11, 2020.[Abstract]


Metals like aluminium (Al) and copper (Cu) are excessively used in electrical, automobile, nuclear, and structural applications because of their desirable electrical and mechanical properties. Joining of components made of pure Al and Cu is one of the challenging areas of research, because of the rapid oxidation characteristics of Al and intense formation of Al-Cu intermetallics in the joint interface. The existing welding techniques such as laser welding, metal inert gas welding, and arc welding have hardships in the development of joint between Al and Cu with desirable metallurgical and mechanical properties. Friction welding is a solid-state joining technique that utilises the frictional heat to develop the joint between the materials at relatively low temperatures. In this study, the effect of friction welding parameter on the microstructure and mechanical properties of friction welded pure Al and Cu were studied. Besides, the microstructural evolution in friction welding Al and Cu with Fe particle reinforcement was analysed. The elemental composition and phases were analysed using energy dispersive x-ray spectroscopy and x-ray diffraction analysis. The microstructural analysis revealed that Fe particles reduced the formation of Al-Cu intermetallic phases at the joint interface.

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2020

M. Abdul Hadi Baig, Vaira Vignesh R., Dr. Padmanaban R., and Dr. Govindaraj M., “Characterization of AA5052-ZrO2 and AA5052-SiO2 Surface Composites Fabricated by Friction Stir Processing”, Songklanakarin Journal of Science and Technology. (Accepted) , 2020.

2020

M. B Bharathi, Vaira Vignesh R., Dr. Padmanaban R., and Dr. Govindaraj M., “Effect of friction stir processing and heat treatment on the corrosion properties of AZ31 alloy”, Australian Journal of Mechanical Engineering, pp. 1–10, 2020.[Abstract]


Magnesium alloys are widely used to lightweight the components in the automobile, aerospace, and electronics industries because of their low density and high specific strength. However, factors like low ductility, low mechanical strength, and high corrosion rate restrict the extensive use of the material. To utilise the alloy with improved mechanical and corrosion properties, friction stir processing followed by heat treatment was performed. The study explored the effect of ageing temperature and ageing time on the microstructure, mechanical and corrosion properties of friction stir processed AZ31 alloy. The results indicate that friction stir processing at TRS of 1200 rpm and TTS of 60 mm/min, followed by heat treatment augments the corrosion resistance of AZ31 alloy.

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2020

V. Shrinaath, Vaira Vignesh R., and Dr. Padmanaban R., “Parametric Study on the Spring-Back Effect in AA5052 Alloy in the Course of Three-Point Roll Bending Process”, Acta Mechanica et Automatica, vol. 14, no. 3, pp. 128-134, 2020.[Abstract]


Three-point roll bending is one of the most common forming processes employed to obtain the desired radius of curvature in the sheet metal operations. Upon the removal of the forming load, the sheet metal deforms to a lesser extent than that of the required dimension. This phenomenon is termed as spring-back and is considered the most challenging areas of research in three-point roll bending of sheet metals. This study aims to develop a numerical model using HyperWorks and Radioss solver to understand the influence of load, the distance between the forming rollers, and its thickness on the spring-back effect in the course of three-point roll bending of sheet metal (AA5052). The results of the numerical model are validated with the results of the experimental trials. Besides, a statistical model is developed to relate the amount of spring-back with the three-point roll bending process parameters.

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2020

Dr. Padmanaban R., Balusamy, V., and Vaira Vignesh R., “Effect of friction stir welding process parameters on the tensile strength of dissimilar aluminum alloy AA2024-T3 and AA7075-T6 joints”, Materialwissenschaft und Werkstofftechnik, vol. 51, no. 1, pp. 17–27, 2020.[Abstract]


This work investigates the influence of friction stir welding parameters on the mechanical properties of the dissimilar joint between AA2024‐T3 and AA7075‐T6. Experiments are conducted consistent with the three‐level face‐centered composite design. Response surface methodology is used to develop the regression model for predicting the tensile strength of the joints. The analysis of variance technique is used to access the adequacy of the developed model. The model is used to study the effect of key operating process parameters namely, tool rotation speed, welding speed and shoulder diameter on the tensile strength of the joints. The results indicate that friction stir welding of aluminum alloys at a tool rotation speed of 1050 min<sup>−1</sup>, welding speed of 40 mm/min and a shoulder diameter of 17.5 mm would produce defect less joint with high tensile strength.

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2020

M. Muralimanokar, Vaira Vignesh R., Govindaraju, M., and Dr. Padmanaban R., “Characterization of AZ31-NbC Surface Composite Fabricated by Friction stir Processing”, Koroze a ochrana materiálu, vol. 64, pp. 29-37., 2020.[Abstract]


AZ31D magnesium alloy is widely used in automotive, aircraft, and aerospace applications because of its high strength to weight ratio. However, the softness of the alloy results in higher wear rate and the high activity results in higher corrosion rate. With an aim of reducing the wear rate and corrosion rate of AZ31 alloy, surface composite of AZ31 alloy is fabricated by reinforcing niobium carbide (NbC) by friction stir processing. The microstructure and dispersion of the reinforcements in AZ31-NbC surface composite is analysed by optical microscopy. In addition, the microhardness and tribological characteristics of the developed AZ31-NbC surface composite are investigated. The results demonstrated an increase in microhardness (23.2 %) and the decrease in wear rate (15.6 % for a normal load of 2 kg) in the developed AZ31-NbC surface composite with respect to the base material. The immersion corrosion test was performed to analyse the corrosion rate of the developed AZ31-NbC surface composite in simulated sea water environment (3.5 wt % NaCl solution). The results indicate that the corrosion rate of the developed AZ31-NbC surface composite is higher than that of base material. A comprehensive analysis on the wear and corrosion mechanism of the developed AZ31-NbC surface composite is presented.

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2020

Vaira Vignesh R., Dr. Padmanaban R., Kovukkal, M. D., and Dr. Govindaraj M., “Research and Development in Magnesium Alloys for Industrial and Biomedical Applications: A Review”, Metals and Materials International, vol. vol. 26, pp. 409-430, 2020.[Abstract]


Abstract: The work reviews the research and development status of magnesium alloy, with more attention to the methodologies and technologies adopted to improve the properties of AZ91 alloy. The drive force of utilizing magnesium alloys for automotive and biomedical application is light weightiness and biocompatibility respectively. However, the softness and high activity of magnesium alloys result in high wear and high corrosion rate respectively. One of the essential factors influencing the properties of magnesium alloy is its microstructure. Consequently, the grain size, morphology and distribution of phase constituents influence the properties of magnesium alloys. The modification of microstructure through processing route (hot working and cold working), heat treatment, and alloying elements improves the mechanical, corrosion, biocompatible, and tribological properties of magnesium alloys. Besides microstructural modification processes, addition of reinforcements, and coatings improves the properties of magnesium alloys. This article emphasis on the recent research on the technologies to improve the microstructure, hardness, tensile strength, ductility, yield strength, wear resistance, and corrosion resistance of magnesium alloy AZ91. Moreover, this review addresses the key issues hindering the applications of magnesium alloys for structural and biomedical applications. Graphic Abstract: [Figure not available: see fulltext.]. © 2019, The Korean Institute of Metals and Materials.

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2020

Vaira Vignesh R., Dr. Padmanaban R., and Dr. Govindaraj M., “Synthesis and Characterization of Magnesium Alloy Surface Composite (AZ91D - SiO2) by Friction Stir Processing for Bioimplants”, Silicon, vol. 12, 2020.[Abstract]


Magnesium shows potential for bioimplant applications because of its high biocompatibility and equivalent bone strength. However, the high corrosion rate of magnesium and magnesium alloys in the physiological environment results in the rapid evolution of H2 gas, which is lethal to the neighboring tissues. With an intention to reduce the corrosion rate, magnesium alloy AZ91D is reinforced with nanophase SiO2 to fabricate surface composite by friction stir processing. The metallurgical characterization reveals the refinement of grains, fine dispersion of β phase and nanophase SiO2 in the composite matrix. The surface characterization of the corrosion products depicts the formation of an adherent layer of corrosion products that are rich in calcium hydroxyapatite and calcium-magnesium phosphate. The combined consequence of metallurgical and corrosion phenomenon reduces the corrosion rate, aids bone growth, and augments implant-bone integration. The results demonstrate that AZ91D-SiO2 composite is an effective material for bioimplant applications. [Figure not available: see fulltext.]. © 2019, Springer Nature B.V.

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2019

C. K, M, S. Prasad, C, L. Rao, and Dr. Padmanaban R., “Study of the Influence of coiling-uncoiling induced residual stresses on the fatigue behavior of truck frame rail sections”, Journal of Engineering Science and Technology, vol. 14, no. 3, pp. 1161-1172., 2019.[Abstract]


Coiling of steel sheet is one of the easiest methods adopted by steel mills for the compact transportation of bulk sheet material to truck manufacturers for making 'C' shaped side frame rails. The coiling-uncoiling operation induces residual stresses in the steel sheet due to plastic strain hardening. This initial imperfection in the form of residual stresses remains in the plain web and flange areas of the rail sections. In corner areas of frames, increase in residual stresses are observed due to severe plastic deformation from forming operation than the coilinguncoiling operation. More accurate consideration of the residual stresses becomes necessary when the behaviour of truck side frame rail web and flange sections, derived from different coil diameters are assessed. In this work, micro-hardness measurement is employed to predict the extent of plastic deformation at different coil diameter locations. The residual stresses induced by the coiling-uncoiling operation is assessed using the X-ray diffraction technique for steel coil diameters ranging from 600 mm to 1800 mm. Fatigue tests on samples extracted from different coil diameters indicate that fatigue life increases with the increase in coil diameter of the sample. The fatigue life of the annealed flat test sample was found to be higher than the fatigue life of samples derived from different coil diameter locations of steel coils received from steel mills

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2019

A. Aravind, Vaira Vignesh R., Dr. Padmanaban R., and Dr. Govindaraj M., “Study on the Mechanical and Corrosion behavior of AA 5052 Tailor Welded Blanks Fabricated using Friction Stir Welding”, Journal of Materials and Environmental Sciences, vol. 10, no. 7, pp. 624-636, 2019.[Abstract]


Friction stir welding is a unique and promising technique to produce joints with desirable mechanical strength and properties. Tailor welded blanks are processed by joining two plates of dissimilar thickness with relatively less mass. As tailor welded blanks offer higher strength at a minimal weight, the material consumption decreases making it more economically viable. In this study, the influence of the critical friction stir welding process parameters namely tool traverse speed, tool rotation speed and thickness mismatch ratio on the microhardness, corrosion rate, tensile strength (before and after corrosion) of AA5052 tailor welded blanks are investigated. The friction stir welding trials were conducted based on Box Behnken design at three levels of process parameters. Hybrid-Radial Basis Function based models were developed to explore the effect of process parameters on the properties. The optimum process parameters to obtain high tensile strength in AA5052 tailor welded blanks was found to be tool traverse speed of 60mm/min, the tool rotation speed of 850rpm and thickness mismatch ratio of 0.9.

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2019

Vaira Vignesh R., Dr. Padmanaban R., Dr. Govindaraj M., and G. Priyadharshini, S., “Investigations on the corrosion behaviour and biocompatibility of magnesium alloy surface composites AZ91D-ZrO2 fabricated by friction stir processing”, Transactions of the Institute of Metal Finishing (The International Journal of Surface Engineering and Coatings), vol. 97, no. 5, pp. 261-270, 2019.[Abstract]


In the current study, friction stir processing was applied as a methodology to produce surface composites of AZ91D magnesium alloy with ZrO2 particles. Microstructural evolution, microhardness profile and corrosion behaviour of the developed surface composite were analysed. The results indicate that the combined effect of friction stir processing and reinforcement of ZrO2 reduced the grain size, and fragmented and dispersed the secondary phases. The fine dispersion of ZrO2 particles contributed to the enhancement of cumulative surface potential, and hence the corrosion resistance of the developed surface composite. The analysis of post-corrosion test specimens revealed the formation of corrosion products that had similar composition to that of hydroxyapatite. The formation of such corrosion products is beneficial, as it contributes to corrosion resistance (stable and adherent layer) and biocompatibility. © 2019, © 2019 Institute of Materials Finishing Published by Taylor & Francis on behalf of the Institute.

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2019

Vaira Vignesh R., Dr. Padmanaban R., and Govindaraju, M., “Study on the Corrosion and Wear Characteristics of Magnesium Alloy AZ91D in Simulated Body Fluids”, Bulletin of Materials Science, vol. 43, no. 8, pp. 1-12, 2019.

2019

Dr. Padmanaban R., Balusamy, V., and Vaira Vignesh R., “Effect of FSW process parameters on the tensile strength of dissimilar aluminum alloy AA2024-T3 and AA7075-T6 joints”, Materialwissenschaft und Werkstofftechnik (Article in Press) , 2019.

2019

Dr. Ilangovan S., Vaira Vignesh R., Dr. Padmanaban R., and Dr. Gokulachandran J., “Effect of composition and aging time on hardness and wear behavior of Cu-Ni-Sn spinodal alloy”, Journal of Central South University, vol. 26, no. 10, pp. 2634-2642, 2019.[Abstract]


Copper alloyed with various compositions of nickel and tin were cast into molds under argon atmosphere. The cast rods were homogenized, solution heat treated, followed by aging for different time duration. The specimens were characterized for microstructure and tested for microhardness and wear rate. A hybrid model with a linear function and radial basis function was developed to analyze the influence of nickel, tin, and aging time on the microhardness and tribological behavior of copper-nickel-sin alloy system. The results indicate that increase in the composition of nickel and tin increases the microhardness and decreases the wear rate of the alloy. The increase in the concentration of nickel and tin decreases the peak aging time of the alloy system. © 2019, Central South University Press and Springer-Verlag GmbH Germany, part of Springer Nature.

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2019

Dr. Govindaraj M., Vaira Vignesh R., and Dr. Padmanaban R., “Effect of heat treatment on the microstructure and mechanical properties of the friction stir processed AZ91D magnesium alloy”, Metal Science and Heat Treatment, vol. 61, no. 5, pp. 311–317, 2019.[Abstract]


We study the microstructure and mechanical properties of friction stir processed AZ91D cast magnesium alloy under various conditions of heat treatment. It is shown that, in the initial as-cast state, the structure of the alloy contained a continuously networked β-phase with an average grain size of 150 μm. The friction stir processed (FSP) specimens had an average grain size of 12 μm and smooth grain boundaries. The subsequent heat treatment of the FSP specimens at various temperatures between 150°C and 250°C led to the appearance of numerous particles of the β-phase. The FSP specimens heat-treated at 200°C had finer grains, a larger number of fine particles of the β-phase, and better mechanical properties than any other specimens.

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2019

V. R. Barath, Tak, M., Dr. Padmanaban R., and Padmanabham, G., “Adaptive process control for uniform laser hardening of complex geometries using iterative numerical simulation”, Materials Performance and Characterization, vol. 8, no. 6, 2019.[Abstract]


Laser surface hardening, when applied to complex geometries, poses a challenge in the terms of obtaining uniform hardness throughout the hardened area because of variable heat sink effects. In this work, an iterative numerical approach was used to estimate the required modulation in laser power to achieve a uniform surface temperature throughout the process zone. Firstly, a transient thermal model for the laser–material interaction was developed using the finite element method for a rectangular spot of 8 × 5 mm. The temperature-dependent material properties were used to bring in nonlinear effects in the analysis so as to predict the hardened zone dimensions more precisely. The numerical model was validated by carrying out laser hardening experiments using a 6-kW diode laser. The validated numerical model was used with an iterative technique aided by conditional looping to achieve a uniform surface temperature during the laser hardening of the complex geometry with a variable heat sink. The developed iterative approach can be effectively used on any geometry with a variable heat sink to obtain a constant surface temperature throughout the process zone. Copyright © 2019 by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959

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2019

Vaira Vignesh R., Dr. Padmanaban R., Dr. Govindaraj M., and G. Priyadharshini, S., “Mechanical properties and corrosion behaviour of AZ91D-HAP surface composites fabricated by friction stir processing”, Materials Research Express, vol. 6, no. 8, 2019.[Abstract]


The biomedical applications of magnesium alloy AZ91D are limited because of the dendritic β-Mg17Al12 phase, which degrades the mechanical properties and corrosion resistance. To overcome this, friction stir processing is implemented to fabricate surface composite of AZ91D with hydroxyapatite as reinforcement. This results in refinement of grains and fragmentation of the β phase with homogeneous dispersion of hydroxyapatite in the composite. The combined effect of reinforcement of hydroxyapatite and fragmentation of the β phase resulted in simultaneous improvement in mechanical and corrosion properties. The various phases, surface morphology, and composition of the developed composite are analyzed using a transmission electron microscope and a scanning electron microscope before and after corrosion studies. The mechanism behind the improvement in the property of the developed composite is correlated with the characterization results. © 2019 IOP Publishing Ltd.

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2019

Vaira Vignesh R., Dr. Padmanaban R., and Dr. Govindaraj M., “Investigations on the surface topography, corrosion behavior, and biocompatibility of friction stir processed magnesium alloy AZ91D”, Surface Topography: Metrology and Properties, vol. 7, no. 2, 2019.[Abstract]


Magnesium and its alloys have been identified as potential biodegradable implant materials for orthopaedic applications considering their bone equivalent density, biocompatibility, and biodegradability. However, the rapid corrosion rate of magnesium alloys in the physiological environment is a severe problem. This study attempts to simultaneously improve the microhardness and reduce the corrosion rate of AZ91D alloy by friction stir processing. Magnesium alloy AZ91D is friction stir processed by varying the process parameters namely tool rotation speed and tool traverse speed. The effects of friction stir processing parameters on the microstructural evolution, surface topography, microhardness, and corrosion rate of AZ91D alloy are investigated using the hybrid models, which are developed by integrating the quadratic function and radial basis function. The results indicate that the optimum process parameters for friction stir processing of AZ91D alloy is 750 rpm and 45 mm min-1. Cytotoxicity test revealed that the biocompatibility of friction stir processed AZ91D alloy is in good agreement with the biocompatibility of the AZ91D alloy. © 2019 IOP Publishing Ltd.

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2018

M. N. Abijith, Nair, A. R., Aadharsh, M., Vaira Vignesh R., Dr. Padmanaban R., and Arivarasu, M., “Investigations on the mechanical, wear and corrosion properties of cold metal transfer welded and friction stir welded aluminium alloy AA2219”, Jordan Journal of Mechanical and Industrial Engineering, vol. 12, no. 4, pp. 281-292, 2018.[Abstract]


Aluminium - Copper alloy AA2219 finds application in aerospace and automotive components because of its high strength to weight ratio and corrosion resistance. However, joining of the alloy by conventional welding techniques results in poor property profile. In this study, AA2219 rolled plates of thickness 5.5 mm are joined by cold metal transfer welding process and friction stir welding process. The microstructure, mechanical, corrosion and wear properties of the welded plates are analyzed. The results indicate that cold metal transfer welded specimens have high hardness and tensile strength than the friction stir welded specimens. However, the corrosion resistance and wear resistance of friction stir welded specimens are higher than the base material and cold metal transfer welded specimens. © 2018 Jordan Journal of Mechanical and Industrial Engineering.

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2018

K. Chinnaraj, M. Prasad, S., C. Rao, L., and Dr. Padmanaban R., “Investigation of Residual Stresses in Cold-Formed Steel Sections with Nonlinear Strain-Hardened Material Model”, SAE International Journal of Materials and Manufacturing, vol. 11, 2018.[Abstract]


In this article, forming residual stresses in cold-formed small-radius corner sections are analytically predicted with the consideration of the shift in the neutral axis and the nonlinear strain-hardened material model. The predicted forming stress results in the transverse direction show a trend of increased compressive residual stress in the outer surface and reduced tensile residual stress in the inner surface, as the corner radius-to-thickness ratio increases in small-radius bends. In the longitudinal direction, there is no significant change in the residual stress values observed in the inner and outer surfaces with respect to an increase in corner radius-to-thickness ratios. But a considerable decrease in compressive residual stress and an increase in tensile stress values are observed in the midsection areas, with an increase in the corner radius-to-thickness ratio. It is observed that the analytical peak compressive residual stress values are always higher than the experimental results. Also, the through-thickness residual stress from the numerical model is in close agreement with the analytical results. The magnitude of the maximum compressive stress in the inner half thickness is observed to be more than the magnitude of the maximum tensile stress in the outer half thickness of the corner section. The shift in the neutral axis towards the inner corner surface is much severe for lower corner radius-to-thickness ratio sections. The new approach provides a more accurate definition of initial conditions for further nonlinear structural behavior analysis of cold-formed structures. Copyright © 2018 SAE International.

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2018

Vaira Vignesh R., Dr. Padmanaban R., and Chinnaraj, K., “Soft computing model for analysing the effect of friction stir processing parameters on the intergranular corrosion susceptibility of aluminium alloy AA5083”, Koroze a Ochrana Materialu, vol. 62, no. 3, pp. 97-107, 2018.[Abstract]


Aluminium alloy AA5083 is prone to intergranular corrosion in marine environments. In an attempt to reduce the intergranular corrosion, AA5083 was subjected to friction stir processing (FSP). The FSP experimental trials were conducted as per face-centered central composite design with three levels of variation in FSP process parameters viz. tool rotation speed (TRS), tool traverse speed (TTS) and tool shoulder diameter (SD). Intergranular corrosion susceptibility of the processed specimens was assessed by performing nitric acid mass loss test. The mass loss of the specimens was correlated with the intergranular corrosion susceptibility as per the standard ASTM G67-13. The experimental results indicate that FSP had significantly reduced the intergranular corrosion susceptibility of the AA5083 alloy. Soft computing techniques namely Artificial Neural Network, Mamdani Fuzzy system, and Sugeno Fuzzy system were used to predict the intergranular corrosion (IGC) susceptibility (mass loss) of the friction stir processed specimens. Among the developed models, Sugeno fuzzy system displayed minimum percentage error in prediction. So Sugeno fuzzy system was used to analyze the effect of friction stir processing process parameters on the IGC of the processed specimens. The results suggest that stir processing of AA5083 at a TRS of 1300 rpm, TTS of 60 mm/min and SD of 21 mm would make the alloy least susceptible to intergranular corrosion. © 2018 Vaira Vignesh R. et al., published by Sciendo 2018.

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2018

Vaira Vignesh R. and Dr. Padmanaban R., “Comparison of ANN training algorithms for predicting the tensile strength of friction stir welded aluminium alloy AA1100”, International Journal of Vehicle Structures and Systems, vol. 10, no. 2, pp. 98-102, 2018.[Abstract]


Aluminium alloy AA1100 finds application in light weight structures due to its high strength to weight ratio. Friction stir welding is a solid state welding process, in which the materials are joined in the plasticized state. The quality of the friction stir welded joints depends on the process parameters used and tool parameters. In this study, four process parameters were varied at five levels and experimental trials were performed as per face centered central composite design. Artificial neural network model was developed with cascade forward propagation network architecture and trained with LM algorithm and BFGS QN algorithm. The models were used to predict the tensile strength of the joints and the error in prediction was used to judge the accuracy of the developed models. It is observed that BFGS QN algorithm trains the ANN efficiently and results in accurate predictions. © 2018.

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2018

Vaira Vignesh R. and Dr. Padmanaban R., “Forecasting Tribological Properties of Wrought AZ91D Magnesium Alloy Using Soft Computing Model”, Russian Journal of Non-Ferrous Metals, vol. 59, no. 2, pp. 135-141, 2018.[Abstract]


The wear characteristics of wrought magnesium alloy AZ91D is assessed by varying the wear test parameters namely sliding velocity, sliding distance and normal load in the pin-on-disc tribometer. The experimental results are used to develop a statistical model, and soft computing models based on artificial neural network and Sugeno–Fuzzy logic to predict the wear rate of AZ91D alloy. Sugeno–Fuzzy model had the highest accuracy in prediction and hence used to study the effect of wear test parameters on the wear rate of AZ91D alloy. It is observed that the wear rate increases with decrease in load, increase in sliding velocity, and increase in sliding distance. © 2018, Allerton Press, Inc.

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2018

Vaira Vignesh R., Dr. Padmanaban R., and Datta, M., “Influence of FSP on the microstructure, microhardness, intergranular corrosion susceptibility and wear resistance of AA5083 alloy”, Tribology - Materials, Surfaces and Interfaces, vol. 12, no. 3, pp. 157-169, 2018.[Abstract]


This article investigates the role of friction stir processing (FSP) process parameters on the evolution of microstructure, hardness, intergranular corrosion resistance and wear resistance of aluminium alloy AA5083. The FSP trials are performed by changing the process parameters as per face-centered central composite design. The friction stir processed (FSPed) specimens subjected to intergranular corrosion test and wear test are characterized using field emission scanning electron microscope, energy dispersive x-ray spectroscopy and X-ray diffraction. Outcomes suggest that grain refinement, dispersion and partial dissolution of secondary phase has simultaneously increased the hardness, intergranular corrosion resistance and wear resistance of the FSPed specimens. The study found that tool rotation speed of 700 rpm, tool traverse speed of 60 mm min−1 and shoulder diameter of 15 mm results in maximum hardness, wear resistance and intergranular corrosion resistance. © 2018 Institute of Materials, Minerals and Mining and Informa UK Limited, trading as Taylor & Francis Group

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2018

Dr. Gokulachandran J. and Dr. Padmanaban R., “Prediction of Remaining Useful life of Cutting Tools: A Comparative Study using Soft Computing Methods”, International Journal of Process Management and Benchmarking, vol. 8, no. 2, pp. 156-181, 2018.[Abstract]


Predicting the remaining useful life of the partially degraded components and putting them to use will help to save natural resources to a great extent. This will reduce the overall cost, energy and protects environment. High productivity cutting tools used in manufacturing industry are generally expensive. As such, the accurate assessment of remaining useful life (for reuse) of any given tool is of great significance in any manufacturing industry. The main objective of this research is to develop a comprehensive methodology to assess the reuse potential of carbide-tipped tools. This paper presents the use of three soft computing methods, namely, artificial neural network, neuro fuzzy logic and support vector regression methods for the assessment of remaining useful life (RUL) of cutting tools. In this work, experiments are conducted based on Taguchi approach and tool life values are obtained. Tool life values are predicted using the aforesaid three soft computing methods and RUL obtained from these values are compared. It is found that the predictive neuro fuzzy method is capable of giving a better prediction of remaining useful tool life than the other methods.

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2017

M. M. Mathew, Bathe, R. N., Padmanabham, G., Dr. Padmanaban R., and Dr. Thirumalini S., “A study on the micromachining of molybdenum using nanosecond and femtosecond lasers”, The International Journal of Advanced Manufacturing Technology, 2017.[Abstract]


Laser micromachining is an advanced machining process in which machining is achieved by focusing a laser beam to melt and vaporize the material. The primary aim of this work is to fabricate a control grid for an electron gun using laser micromachining. Initially, line scribing and 2D profiling experiments are performed on a 130-$μ$m molybdenum plate to compare the surface quality and material removal rate of nanosecond and femtosecond lasers. The effects of laser processing parameters such as average power, repetition rate, and the feed rate on the width, depth, material removal rate, and cut quality of both the nanosecond and femtosecond lasers are studied. During micromachining using the nanosecond laser, melting and recasting of the metal around the machined sites are observed, resulting in the formation of heat-affected zone. During machining using the femtosecond laser, ultrafast laser pulses are used, which result in the absence of heat-affected zone. The surface roughness obtained using the femtosecond laser for creating a 2D profile is 0.187&nbsp;$μ$m, while using the nanosecond laser, the roughness value obtained is 1.89&nbsp;$μ$m. The femtosecond laser is used to successfully machine the 3D profile of the control grid, adopting the optimized parameters obtained from the line scribing and 2D profiling experiments. The average width of the grid line was measured as 149.89&nbsp;$μ$m which is very close to the required dimension of 150&nbsp;$μ$m

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2017

Vaira Vignesh R. and Dr. Padmanaban R., “Modelling Corrosion Behavior of Friction Stir Processed Aluminium Alloy 5083 Using Polynomial: Radial Basis Function”, Transactions of the Indian Institute of Metals, vol. 70, no. 10, pp. 2575–2589, 2017.[Abstract]


Aluminium alloy 5083, widely used in marine applications, undergoes accelerated corrosion in sea water due to the aggressive reaction of chloride ions with the secondary phase particles and other intermetallics present in the alloy matrix. The corrosion rate of the alloy is also influenced by the temperature difference between the alloy and its environment. Friction stir processing (FSP) is a recent solid state processing technique for improving the surface properties of metals and alloys. In this study, an attempt has been made to explore the possibility of improving the corrosion resistance of AA5083 by FSP. FSP trials were performed by varying the tool rotation speed, tool traverse speed and shoulder diameter of the tool, as per face centered central composite design. The corrosion potential and the corrosion rate of friction stir processed AA5083 was studied using potentiodynamic polarization studies, at three different temperatures. Mathematical models based on polynomial–-radial basis function were developed and used to study the effect of process parameters on the corrosion potential and the corrosion rate of friction stir processed AA5083. FSP resulted in refinement of the grain structure, dispersion and partial dissolution of secondary phase particles in the matrix, which increased the corrosion resistance of the alloy.

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2017

M. Arivarasu, Roshith, P., Dr. Padmanaban R., Dr. Thirumalini S., Prabhakar, K. V. Phani, and Padmanabham, G., “Investigations on metallurgical and mechanical properties of CO2 laser beam welded Alloy 825”, Canadian Metallurgical Quarterly, pp. 1-13, 2017.[Abstract]


In the research work, an attempt is made to join nickel-based alloy 825 by employing CO2 laser beam welding. Successful full penetration weld joint of a 5 mm thick plate is achieved with a very low heat input of 120 J-mm−1. Narrow weld bead width of 0.6 mm at the root and 1.6 mm at the cap is observed fusion zone; the interface and base metal microstructures have been examined using both optical and scanning electron microscopic techniques to understand the microstructural changes which have occurred due to laser welding. A range of tests of Vickers micro hardness, tensile and impact tests had been performed on the weldment to ascertain the mechanical properties of the joint. Tensile failure at the base metal and a 180° root bend test conducted on the weldment ascertain the soundness of the weld joint produced. An attempt is made to correlate the microstructure and mechanical properties of the weldment. Intermetallics TiN and Al4C3 observed in the SEM/EDS analysis at the fusion zone are found to have improved the weld metal strength and hardness. © 2017 Canadian Institute of Mining, Metallurgy and Petroleum

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2016

P. Deepak, Jualeash, M. J., Jishnu, J., Srinivasan, P., Arivarasu, M., Dr. Padmanaban R., and Dr. Thirumalini S., “Optimization of process parameters of pulsed TIG welded maraging steel C300”, IOP Conference Series: Materials Science and Engineering, vol. 149, p. 012007, 2016.[Abstract]


Pulsed TIG welding technology provides excellent welding performance on thin sections which helps to increase productivity, enhance weld quality, minimize weld costs, and boost operator efficiency and this has drawn the attention of the welding society. Maraging C300 steel is extensively used in defence and aerospace industry and thus its welding becomes an area of paramount importance. In pulsed TIG welding, weld quality depends on the process parameters used. In this work, Pulsed TIG bead-on-plate welding is performed on a 5mm thick maraging C300 plate at different combinations of input parameters: peak current (Ip), base current (I b ) and pulsing frequency (HZ) as per box behnken design with three-levels for each factor. Response surface methodology is utilized for establishing a mathematical model for predicting the weld bead depth. The effect of Ip, I b and HZ on the weld bead depth is investigated using the developed model. The weld bead depth is found to be affected by all the three parameters. Surface and contour plots developed from regression equation are used to optimize the processing parameters for maximizing the weld bead depth. Optimum values of Ip, I b and HZ are obtained as 259 A, 120 A and 8 Hz respectively. Using this optimum condition, maximum bead depth of the weld is predicted to be 4.325 mm.

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2016

Dr. Padmanaban R., Vaira Vignesh R., Arivarasu, M., Karthick, K. P., and A. Sundar, A., “Process parameters effect on the strength of Friction Stir Spot Welded AA6061”, ARPN Journal of Engineering and Applied Sciences, vol. 11, no. 9, pp. 6030-6035, 2016.[Abstract]


Friction Stir Spot Welding (FSSW) is a recent welding technique used for spot welding of thin sheets. Response surface methodology (RSM) is used to develop a model for the tensile shear failure load of AA6061joined by FSSW. The experiments are conducted for different combinations of three parameters viz. tool rotational speed, dwell time and shoulder diameter as per Box -Behnken design and mathematical model is developed. The developed equation is used to find the optimum parameter combinations for obtaining joints with higher TSFL. © 2006-2016 Asian Research Publishing Network (ARPN). All rights reserved.

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2015

J. James Cheeran, Dr. Padmanaban R., Dr. Thirumalini S., and .Bhaskar, V., “Design and Optimization of a Diesel Engine Connection Rod”, International Journal of Applied Engineering Research, vol. 10, no. 32, 2015.

2015

Dr. Ratna Kishore V., Arun, J., Dr. Padmanaban R., and V, B., “Parametric studies of dissimilar friction stir welding using computational fluid dynamics simulation”, International Journal of Advanced Manufacturing Technology, vol. 80, pp. 91-98, 2015.[Abstract]


A two-dimensional steady state visco-plastic model has been developed for friction stir welding of dissimilar metals using a commercial CFD code, FLUENT®. Volume of Fluid (VOF) approach is used to model the welding process of dissimilar metals. Initially, the model developed is validated against experimental measurements of Peel et al. (Metall Mater Trans A 37 A:2183–2193, 2006). Simulations were done for two different material combinations, AA 5083–AA 6061 and AA 2024–AA 7075. The temperature distribution and material flow around the tool is studied for different position of materials, process parameters, and tool profiles. It is seen that the peak temperature is generated on harder material side with change in position of materials. This is mainly because on harder material side more heat is generated due to viscous dissipation. The trivex pin profile is found to be better than circular pin profile by reducing welding traverse force and an efficient symmetric mixing of materials. © 2015, Springer-Verlag London.

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2015

Dr. Padmanaban R., .Balusamy, V., and .N.Nouranga, K., “Effect of Process Parameters on the Tensile Strength of Friction Stir Welded Dissimilar Aluminum Joints”, Journal of Engineering Science and Technology, vol. 10, no. 6, pp. 790-801, 2015.

2014

A. M. Xavior, Yarlagadda, P. K. D. V., Dr. Padmanaban R., Balusamy, V., Saikrishna, V., and K. Niranthar, G., “Simulated Annealing Based Parameter Optimization for Friction Stir Welding of Dissimilar Aluminum Alloys”, Procedia Engineering, vol. 97, pp. 864 - 870, 2014.[Abstract]


Friction Stir Welding (FSW) is one of the latest solid state joining techniques being extensively used for joining many similar and dissimilar material combinations for structurally demanding applications and the results are promising. The weld qualities of the FSW joints depend on the process parameters used. Aluminum alloys AA2024 and AA7075 find applications in aircraft industries and pose challenges when joined using conventional fusion welding techniques. In this study, friction stir welding of dissimilar aluminum alloys AA2024-AA7075 is performed at different tool rotation speeds (TRS) and welding speeds (WS) as per central composite design with three factors and three-levels for each factor (face centred). Response surface methodology is used a mathematical model for predicting the tensile strength of the resulting joints was developed. The model is used to study the effect of the TRS and WS on the strength of the joints. The tensile strength of the joints is found to be affected by both the TRS and WS. Simulated Annealing is used to optimize the TRS and WS for maximizing the tensile strength of the joints. Optimum values of the TRS and WS are found to be 1087.6rpm and 14.12mm/min respectively. The maximum tensile strength of the joints is predicted to be 271.084MPa when these parameters are used.

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2013

Dr. Gokulachandran J., K. Mohandas, and Dr. Padmanaban R., “Comparative study of two soft computing techniques for the prediction of remaining useful life of cutting tools”, Journal of Intelligent Manufacturing, vol. 26, pp. 255-268, 2013.[Abstract]


Reuse of partially worn-out materials and parts is a philosophy now being applied in all manufacturing industries to achieve the goal of green manufacturing. High productivity cutting tools used in manufacturing industry are generally expensive. As such, the accurate assessment of remaining useful life (for reuse) of any given tool is of great significance in any manufacturing industry. This exercise will in turn reduce the overall cost and help achieve enhanced productivity. This paper reports the use of two soft computing techniques, namely, neuro fuzzy logic technique and support vector regression technique for the assessment of remaining useful life (RUL) of cutting tools. In this work, experiments are conducted based on Taguchi approach and tool life values are obtained. Tool life values are predicted using the aforesaid two soft computing techniques and RUL obtained from these values are compared. © 2013 Springer Science+Business Media New York.

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2012

Dr. Padmanaban R., Balusamy, Vb, and Dr. Ratna Kishore V., “Effect of axial pressure and tool rotation speed on temperature distribution during dissimilar friction stir welding”, Advanced Materials Research, vol. 418-420, pp. 1934-1938, 2012.[Abstract]


A computational fluid dynamics(CFD) based numerical model is developed to predict the temperature distribution during Friction Stir Welding(FSW) of dissimilar aluminum alloys. The effect of tool rotation speed and axial pressure on heat transfer during FSW has been studied. Numerical results indicate that the maximum temperature in FSW process can be increased with the increase of the axial pressure and tool rotation speed. The influence region of the tool shoulder in the direction of thickness can be increased with the increase in the axial pressure on the shoulder. © (2012) Trans Tech Publications, Switzerland

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Publication Type: Book Chapter

Year of Publication Title

2021

A. Naidu, Dr. Padmanaban R., and Vaira Vignesh R., “Optimizing the Conveyor Belt Speed of a Bright Annealing Furnace”, in Advances in Electromechanical Technologies, Lecture Notes in Mechanical Engineering, Springer, 2021, pp. 13-20.[Abstract]


A company’s growth is determined by an increase in its sales numbers and by a decrease in its expenditures. By doing this, the company attains a more significant profit (bottom line). In almost all manufacturing industries, annealing furnaces play a significant role. In this paper, an improvement in the operation of an annealing furnace used in a press shop is attempted. The press shop performs forging of watch cases, and annealing is performed in between every forging stage. This project focuses on increasing the productivity of the furnace by optimizing its conveyor belt speed. Experiments are conducted, and several annealed samples were collected for analysis. Furthermore, hardness and metallographic properties were also studied. With the help of regression plots of hardness and belt speed, and with the help of microstructures, an optimized belt speed was selected. The optimized belt speed is almost 42% more than the original speed used for production, hence increasing productivity.

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2021

Vaira Vignesh R., Dr. Padmanaban R., Dr. Govindaraj M., and G. Priyadharshini, S., “Corrosion protection of Magnesium Alloys in Simulated Body Fluids using Nanophase Al2O3”, in Corrosion Protection at the Nanoscale, (Accepted), Micro and Nano Technologies, Elsevier, 2021.[Abstract]


Friction stir processing is applied to fabricate magnesium alloy AZ91D surface composite reinforced with nanophase Al2O3 particles. The refined microstructure in the developed surface composite is induced by nanophase Al2O3 particles and recovery–recrystallization phenomenon by friction stir processing. The results of electrochemical corrosion test and immersion corrosion test reveal that the corrosion rate of the developed surface composite decreased in simulated body fluids. The study originally reports that the homogeneous dispersion of nanophase Al2O3 particles and formation of an adherent layer of corrosion products (calcium hydroxyapatite and calcium-magnesium phosphate) in the developed surface composite decrease the corrosion rate. Besides, the formation of these corrosion products that mimic the bone matrix would support bone growth and promote integration of implant bone.

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2020

A. M. Siddharth, Dr. Padmanaban R., and Vaira Vignesh R., “Simulation of Friction Stir Welding of Aluminium Alloy AA5052 – Tailor Welded Blanks”, in Intelligent Systems Design and Applications, Advances in Intelligent Systems and Computing, vol. 940, A. Abraham, Cherukuri, A. Kumar, Melin, P., and Gandhi, N., Eds. Cham: Springer International Publishing, 2020, pp. 1-10.[Abstract]


Tailor welded blanks (TWBs) have been utilized by automotive industries to meet the light-weighting demands. Achieving defect free joints in the TWBs of aluminum alloys is a major challenge. Friction stir welding (FSW) has been successful in producing metallurgically sound joints in identical and diverse aluminum alloys. The present work aims at developing a Finite element method, which was used to explore the maximum temperature (Tp), contact status, plastic strain (PS) and energy input (EI) varied upon tool rotation speed (TRS), shoulder diameter (SD), tool traverse speed (TTS) and thickness ratio (TR). The study explored the influence of the FSW process parameters on the responses using a hybrid model integrating the linear function and radial basis function.

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2018

Vaira Vignesh R. and Dr. Padmanaban R., “Modelling Corrosion Phenomenon of Magnesium Alloy AZ91 in Simulated Body Fluids”, in Advances in Mathematical Methods and High Performance Computing, vol. 41, V. K. Singh, Gao, D., and Fischer, A., Eds. Cham: Springer International Publishing, 2018, pp. 471–486.[Abstract]


Magnesium alloy AZ91 is one of the best suited biodegradable biomaterials for bioimplants. Magnesium is a highly active metal with accelerated corrosion in physiological environments. AZ91 alloy has two distinct phases in the matrix, which form galvanic couple inducing micro galvanic corrosion (primary phase anodic with respect to the secondary phase) in the alloy. However, the corrosion rate could be controlled by tailoring the microstructure of the alloy. The distribution and dispersion of secondary phase particles greatly influence the corrosion rate of the material. A numerical model was developed using Comsol Multiphysics® to study the effect of distribution of secondary phase on the corrosion rate of the alloy. The average anodic current density was found to be higher for AZ91 with continuous network secondary phase microstructural configuration. The average anodic corrosion current and the corrosion rate were found to be lower for AZ91 with dispersed secondary phase microstructural configuration. The numerical modelling results were found to be consistent with the experimental results available in the literature.

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2018

Dr. Ilangovan S., Vaira Vignesh R., Dr. Padmanaban R., and Dr. Gokulachandran J., “Comparison of statistical and soft computing models for predicting hardness and wear rate of Cu-Ni-Sn alloy”, in Progress in Computing, Analytics and Networking, Advances in Intelligent Systems and Computing, vol. 710, , Ed. Springer Verlag, 2018, pp. 559-571.[Abstract]


Castings of Copper–Nickel–Tin alloy were produced by varying the composition of Ni and Sn. The cast specimens were subjected to homogenization and solution treatment. The specimens were characterized for microstructure, hardness and subjected to adhesive wear test. Statistical regression model, artificial neural network model and Sugeno fuzzy model were developed to predict the hardness and wear rate of the alloy based on %Ni, %Sn and ageing time of the specimens. As Sugeno Fuzzy logic model uses adaptive neuro-fuzzy inference system, an integration of neural networks and fuzzy logic principles, the prediction efficiency was higher than statistical regression and artificial neural network model. The interaction effect of %Ni, %Sn and ageing time on the hardness and wear rate of the specimens were analysed using the Sugeno Fuzzy model. © Springer Nature Singapore Pte Ltd. 2018.

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Publication Type: Conference Proceedings

Year of Publication Title

2020

A. Joe Alex, Vaira Vignesh R., Dr. Padmanaban R., and Govindaraju, M., “Effect of heat treatment on the mechanical and wear behavior of friction stir processed AA5052 alloy”, Materials Today: Proceedings (2nd International Conference on Materials Manufacturing and Modelling, ICMMM – 2019), vol. 22. Elsevier, pp. 3340-3346, 2020.[Abstract]


Aluminium alloy AA5052 has excellent strength to weight ratio, which makes it best suited for marine applications. The study explores the effect of heat treatment on the mechanical, corrosion and tribological properties of friction stir processed aluminium alloy AA5052. The micro hardness, tensile strength and wear rate of the base material, friction stir processed and the annealed specimens were analyzed. The results indicate that the FSP followed by annealing increases hardness, tensile strength and resistance to wear of AA5052 alloy

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2019

P. Kesava Sai Srujan, Kaka, H. Krishna, Vaira Vignesh R., Kalyan, K. Pavan, Dr. Padmanaban R., and Dr. Govindaraj M., “Cost-effective manufacturing of piping components with consistent quality through continuous furnace brazing”, AIP Conference Proceedings, vol. 2128. AIP Publishing, p. 030006, 2019.[Abstract]


India is witnessing an incessant expansion in the establishment of manufacturing plants for the production of engineering components by local and foreign players. Adoption of innovative and advanced manufacturing methods improve components’ quality, meet international standards, increase export potential, and achieve “Make in India”. In the pressure vessel and compressor domain, development of suitable brazing technologies for joining piping components will result in properties (joint strength, fatigue strength, wear resistance, corrosion resistance) superior to conventionally welded piping components. For high-volume production, the most common equipment used for brazing is a continuous-type atmosphere-controlled furnace. The cost reduction realized is significant, as this technology is based on the continuous production line. Other advantages include consistency in quality and possibility of automation. This will secure a position for Indian Engineering Component Manufacturers at par with North American, European and Japanese counterparts. In this work, pipe components that are conventionally joined by welding process and amenable for brazing, are identified in terms of design and material (mainly steel based). Steel pipe components are joined by furnace brazing (continuous type) using copper alloy based filler material. The optimum brazing process parameters are established based on the obtained joint strength, corrosion resistance, and leak tightness.

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2019

A. Ashwin, Lakshman, R. B. Hari, Swaroop, C. B. Chand, Vignesh, M., Vaira Vignesh R., and Dr. Padmanaban R., “Predicting the Wear Rate of Aluminum Alloy AA2024-T351 using Hybrid Linear function and Radial Basis Function”, IOP Conference Series: Materials Science and Engineering, vol. 561. IOP Publishing, p. 012046, 2019.[Abstract]


AA2024 is one of the heat treatable Al-Cu alloys with good strength to weight ratio and fracture resistance. It finds application mainly in aircraft and structural applications. In T351 tempered condition, AA2024 has improved hardness and strength. However, the softness of the matrix leads to high wear rate. In this study, tribological characteristics of AA2024-T351 is determined using a pin-on-disc tribometer by varying the sliding velocity, sliding distance and axial load as per face centered central composite design. A hybrid linear – radial basis function model is developed to explore the effect of normal load, sliding distance and sliding velocity on the wear rate of AA2024-T351 alloy. The predominant wear regimes in AA2024-T351 alloy is understood from the characterization study on the surface morphology of the worn specimens.

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2019

R. K Kannan, Vaira Vignesh R., Kalyan, K. Pavan, Murugesan, J., Megalingam, A., Dr. Padmanaban R., and Dr. Govindaraj M., “Tribological performance of heavy-duty functionally gradient friction material (Cu-Sn-Fe-Cg-SiC-Al2O3) synthesized by PM route”, AIP Conference Proceedings, vol. 2128. AIP Publishing, p. 020004, 2019.[Abstract]


Copper-based sintered materials with ceramic reinforcements and solid lubricants are identified as potential brake pad materials for heavy-duty applications (wind turbine), because of their prime thermal and tribological properties. However, the presence of ceramic reinforcement reduces the joint strength between the brake pad and the substrate material. The reduction in joint strength may lead to catastrophic failure of the braking system in the wind turbines when brakes are applied suddenly. This study attempts to synthesize functionally gradient material (FGM), which has a gradient composition of the ceramic particles along the traverse section. FGM was synthesized layer by layer deposition of Cu, Fe, Sn, Cg, SiC, Al2O3 powders with gradient composition. Microstructure, phases, and microhardness of the specimen were analyzed. Tribological studies were performed to assess the wear rate and friction coefficient of the FGM at various loads. The surface morphology of the worn surface was characterized using field emission scanning electron microscope. The study investigated the wear mechanism of the FGM at various loads.

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2019

P. Kumar Chellu, Dr. Padmanaban R., Vaira Vignesh R., Menon, A. S., Shariff, S. M., and Padmanabham, G., “Experimental Study on Laser Welding of AISI 304 Steel with Design of Experiments Approach”, IOP Conference Series: Materials Science and Engineering, vol. 577. IOP Publishing, p. 012117, 2019.[Abstract]


Austenitic stainless steels find extensive applications in engineering and structural parts requiring inherent corrosion resistance. The main objective of this study is to achieve good quality butt joint in 2.5-mm thick 304 grade Stainless Steel. The joint quality is quantified in terms of weld-bead dimensions. The main issue that manufacturers face is controlling the input process parameters, to get a good quality joint, with required weld bead geometry under controlled thermal distortion. The objective of this work is to select proper input process parameters that would result in desirable weld-bead profiles with minimal heat input. The critical process parameters influencing laser-welding were found using response surface methodology technique. The results proved that the developed model could efficiently predict the responses. The criteria demonstrated a possible reduction in top width of weld bead with enhanced depth of penetration, which automatically envisaged an increase in aspect ratio. A two-factor five-level criteria design was used for predicting the optimized parameters by performing multi-response optimization. Among them, the third criterion has shown a significant decrease in heat input and it was chosen as the best-optimized parameter.

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2019

K. B. Arjun, Harikeshava, R., Sreenath, C. R., Srihari, G., Vaira Vignesh R., Vaira Vignesh R., and Dr. Padmanaban R., “Effect of load, sliding distance and sliding velocity on the wear properties of aluminum alloy AA5052”, IOP Conference Series: Materials Science and Engineering, vol. 577. IOP Publishing, p. 012016, 2019.[Abstract]


Aluminum alloys are widely used in engineering applications. In motion established contact applications, wear is an inevitable phenomenon. In this study, the wear mechanism of AA5052was explored using pin-on-disc tribometer. The wear test parameters namely load (kg), sliding distance (m), and velocity (m/s) were varied according to central composite design. The wear tracks of the worn specimens were observed using high-resolution scanning electron microscope and the elemental composition was analysed using energy dispersive X-ray spectroscopy. A hybrid model integrating the linear function and radial basis function was developed to explore the effect of load, sliding distance, and sliding velocity on the wear rate of the AA5052 alloy. The results indicate that increase in axial load and sliding distance decreases the wear rate of the AA5052 alloy.

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2018

Vaira Vignesh R. and Dr. Padmanaban R., “Influence of friction stir processing parameters on the wear resistance of aluminium alloy AA5083”, Materials Today: Proceedings, vol. 5. Elsevier Ltd, pp. 7437-7446, 2018.[Abstract]


In this study, friction stir processing was applied on AA5083, with an objective to improve its wear resistance. FSP was conducted by varying tool rotation speed, tool traverse speed and tool shoulder diameter as per face centered central composite design. Adhesive wear test was performed using a pin-on-disc tribometer. The test results indicate that the wear resistance of most of the friction stir processed specimens was higher than the base material. A mathematical model was generated for predicting the wear resistance using linear-radial basis function and it was used to explore the influence of process parameters on the wear resistance. © 2017 Elsevier Ltd.

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2018

Dr. Padmanaban R., Vaira Vignesh R., Povendhan, A. P., and Balakumharen, A. P., “Optimizing the tensile strength of friction stir welded dissimilar aluminium alloy joints using particle swarm optimization”, Materials Today: Proceedings, vol. 5. Elsevier Ltd, pp. 24820-24826, 2018.[Abstract]


Aluminium alloys AA2024 and AA7075 plates were friction stir welded by varying the tool rotation speed and welding speed and corresponding tensile strength of the joints were measured. A mathematical model was developed using response surface methodology to predict the tensile strength of the joints. The FSW process parameters were optimized for maximizing the tensile strength using particle swarm optimization algorithm. The optimum FSW process parameters for dissimilar welding of AA2024 and AA7075 plates were deduced as welding speed of 15 mm/min and tool rotation speed of 1087 rpm. © 2018 Elsevier Ltd.

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2018

Vaira Vignesh R. and Dr. Padmanaban R., “Intergranular corrosion susceptibility of friction stir processed aluminium alloy 5083”, Materials Today: Proceedings, vol. 5. Elsevier Ltd, pp. 16443-16452, 2018.[Abstract]


The amalgamation of high strength and low density of aluminium alloys makes it suitable for light weight structural applications. Aluminium alloy AA5083 is prone to intergranular corrosion, when exposed to aggressive chloride containing marine environments. When aluminium alloy 5083 is exposed to marine environments, the continuous network of secondary phase particles present in the matrix reacts with the chloride ions and dissolves into the solution, creating new cites for corrosion. In addition to this phenomenon, secondary phase particles form galvanic couple with primary phase of the matrix, accelerating the corrosion. With an objective to improve the intergranular corrosion resistance, AA5083 was subjected to friction stir processing (FSP). FSP trials were conducted by varying the tool rotation speed, tool traverse speed and tool shoulder diameter, as per face centered central composite design. The intergranular corrosion susceptibility of friction stir processed AA5083 was studied by nitric acid mass loss test according to the ASTM G67-04 standard. Mathematical model was generated using linear - radial basis function and the model was used to study the effect of process parameters on the intergranular corrosion susceptibility of friction stir processed AA5083. The results indicate that FSP results in refinement of grain structure, dispersion and partial dissolution of secondary phase particles in the matrix, thereby reducing the intergranular corrosion susceptibility of AA5083. © 2017 Elsevier Ltd.

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2018

Vaira Vignesh R. and Dr. Padmanaban R., “Artificial neural network model for predicting the tensile strength of friction stir welded aluminium alloy AA1100”, Materials Today: Proceedings, vol. 5. Elsevier Ltd, pp. 16716-16723, 2018.[Abstract]


Friction stir welding (FSW) is a solid state welding technique, in which high strength weldswith minimal defects, can be obtained even with materialsthat are hardly weldable by conventional techniques. FSW is influenced by a number of process parameters. Some of the highly influential process parameters that determine the quality of the welds in FSW are tool rotation speed, welding speed, shoulder diameter and pin diameter of tool. In this study, FSW trials were conducted on AA1100 as per central composite design, with four parameters varied at five levels. The tensile strength of the joints were measured using a computerized tensile testing machine and these results were used to develop an artificial neural network model. The input parameters to the model were tool rotation speed, welding speed, shoulder diameter and pin diameter and the output was tensile strength of the joints. Levenberg Marquardt algorithm was used to establish the relationship between the process parameters and the output. The feed forward model was trained using 80% of the experimental data and the remaining 20% of the data was used for validation and testing of the model. The R2 valuesfor validation data and testing datawere found to be 0.80and0.99respectively, displaying the closeness between the experimental and predicted data. The results indicate that the generated model has high efficacy in predicting the tensile strength of friction stir welded aluminium alloy AA1100 joints. © 2017 Elsevier Ltd.

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2018

C. B. Kiruthi Murugan, Balusamy, V., Dr. Padmanaban R., and Vaira Vignesh R., “Friction surfacing mild-steel with Monel and predicting the coating parameters using fuzzy logic”, Materials Today: Proceedings, vol. 5. Elsevier Ltd, pp. 16402-16410, 2018.[Abstract]


Engineering components made of AISI 1012 are susceptible to stress corrosion cracking in marine environments, where more free chloride ions are present. The cladding of Monel over the surface of the AISI 1012 components improves the corrosion resistance. Friction surfacing is an emerging solid-state technique for coating consumables (mostly metallic materials) in the form of the rod over the solid substrate. In this study, FS trials were conducted as per central composite design with five levels of variation for each FS process parameters. Width and thickness of the coating were measured for all the friction surfaced specimens. Soft computing model relating the FS process parameters to the coating thickness and width was generated using the fuzzy logic technique. It is observed that the spindle speed and surfacing speed have an inverse relationship with coating parameters. Increasing the axial load increased the coating thickness and width. © 2017 Elsevier Ltd.

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2018

B. K. Murugan, Balusamy, V., Dr. Padmanaban R., and Vaira Vignesh R., “Study of the effect of parameters in friction surfacing of Monel over Mild Steel using linear - Radial basis function model”, Materials Today: Proceedings, vol. 5. Elsevier Ltd, pp. 8604-8611, 2018.[Abstract]


This paper investigates suitability of friction surfacing (FS) for cladding AISI 1012 with Monel K500. FS trials were conducted by varying the spindle speed, axial pressure and the horizontal feed rate. The thickness and width of the coating were measured and the data were used to develop radial basis function network model relating the FS process parameters with the coating thickness and width. The model was used to analyze the variation of coating thickness and width. The coating thickness and width decreased with increase in spindle speed and horizontal feed rate, while they increased with increase in axial load. © 2017 Elsevier Ltd.

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2018

C. Jayakarthick, Povendhan, A. P., Vaira Vignesh R., and Dr. Padmanaban R., “Analysing the influence of FSP process parameters on IGC susceptibility of AA5083 using Sugeno - Fuzzy model”, IOP Conference Series: Materials Science and Engineering, vol. 310. Institute of Physics Publishing, p. 012043, 2018.[Abstract]


Aluminium alloy AA5083 was friction stir processed to improve the intergranular corrosion (IGC) resistance. FSP trials were performed by varying the process parameters as per Taguchi's L18 orthogonal array. IGC resistance of the friction stir processed specimens were found by immersing them in concentrated nitric acid and measuring the mass loss per unit area. Results indicate that dispersion and partial dissolution of secondary phase increased IGC resistance of the friction stir processed specimens. A Sugeno fuzzy model was developed to study the effect of FSP process parameters on the IGC susceptibility of friction stir processed specimens. Tool Rotation Speed, Tool Traverse Speed and Shoulder Diameter have a significant effect on the IGC susceptibility of the friction stir processed specimens. © Published under licence by IOP Publishing Ltd.

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2018

Vaira Vignesh R. and Dr. Padmanaban R., “Modelling of peak temperature during friction stir processing of magnesium alloy AZ91”, IOP Conference Series: Materials Science and Engineering , vol. 310. Institute of Physics Publishing, p. 012019, 2018.[Abstract]


Friction stir processing (FSP) is a solid state processing technique with potential to modify the properties of the material through microstructural modification. The study of heat transfer in FSP aids in the identification of defects like flash, inadequate heat input, poor material flow and mixing etc. In this paper, transient temperature distribution during FSP of magnesium alloy AZ91 was simulated using finite element modelling. The numerical model results were validated using the experimental results from the published literature. The model was used to predict the peak temperature obtained during FSP for various process parameter combinations. The simulated peak temperature results were used to develop a statistical model. The effect of process parameters namely tool rotation speed, tool traverse speed and shoulder diameter of the tool on the peak temperature was investigated using the developed statistical model. It was found that peak temperature was directly proportional to tool rotation speed and shoulder diameter and inversely proportional to tool traverse speed. © Published under licence by IOP Publishing Ltd.

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2018

V. R. Barath, Vaira Vignesh R., and Dr. Padmanaban R., “Analysing the strength of friction stir welded dissimilar aluminium alloys using Sugeno Fuzzy model”, IOP Conference Series: Materials Science and Engineering, vol. 310. Institute of Physics Publishing, p. 012043, 2018.[Abstract]


Friction stir welding (FSW) is a promising solid state joining technique for aluminium alloys. In this study, FSW trials were conducted on two dissimilar plates of aluminium alloy AA2024 and AA7075 by varying the tool rotation speed (TRS) and welding speed (WS). Tensile strength (TS) of the joints were measured and a Sugeno - Fuzzy model was developed to interconnect the FSW process parameters with the tensile strength. From the developed model, it was observed that the optimum heat generation at WS of 15 mm.min-1 and TRS of 1050 rpm resulted in dynamic recovery and dynamic recrystallization of the material. This refined the grains in the FSW zone and resulted in peak tensile strength among the tested specimens. Crest parabolic trend was observed in tensile strength with variation of TRS from 900 rpm to 1200 rpm and TTS from 10 mm.min-1 to 20 mm.min-1. © Published under licence by IOP Publishing Ltd.

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2016

Vaira Vignesh R., Dr. Padmanaban R., Arivarasu, M., Karthick, K. P., Sundar, A. A., and Dr. Gokulachandran J., “Analysing the strength of friction stir spot welded joints of aluminium alloy by fuzzy logic”, IOP Conference Series: Materials Science and Engineering (International conference on advances in Materials and Manufacturing Applications(ICONAMMA 2016)), vol. 149. Institute of Physics Publishing, p. 012136, 2016.[Abstract]


Friction stir spot welding (FSSW) is a recent joining technique developed for spot welding of thin metal sheets. This process currently finds application in automotive, aerospace, marine and sheet metal industry. In this work, the effect of FSSW process parameters namely tool rotation speed, shoulder diameter and dwell time on Tensile shear failure load (TSFL) is investigated. Box-Behnken design is selected for conducting experiments. Fuzzy based soft computing is used to develop a model for TSFL of AA6061 joints fabricated by FSSW. The interaction of the process parameters on TSFL is also presented. © Published under licence by IOP Publishing Ltd.

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2016

Vaira Vignesh R., Dr. Padmanaban R., Arivarasu, M., Dr. Thirumalini S., Dr. Gokulachandran J., and Ram, M. Sesha Saty, “Numerical modelling of thermal phenomenon in friction stir welding of aluminum plates”, IOP Conference Series: Materials Science and Engineering, vol. 149. p. 012208, 2016.[Abstract]


Friction stir welding (FSW) is a solid state welding process with potential to join materials that are non weldable by conventional fusion welding techniques. The study of heat transfer in FSW aids in the identification of defects like flash, inadequate heat input, poor material flow and mixing etc. In this paper, transient temperature distribution during FSW of aluminum alloy AA6061-T6 was simulated using finite element modelling. The model was used to predict the peak temperature and analyse the thermal history during FSW. The effect of process parameters namely tool rotation speed, tool traverse speed (welding speed), shoulder diameter and pin diameter of tool on the temperature distribution was investigated using two level factorial design. The model results were validated using the experimental results from the published literature. It was found that peak temperature was directly proportional to tool rotation speed and shoulder diameter and inversely proportional to tool traverse speed. The effect of pin diameter on peak temperature was found to be trivial.

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2015

Vaira Vignesh R. and Dr. Padmanaban R., “Corrosion of Aluminium and Magnesium Alloys: A Review”, International Conference on Modelling, Simulation and Control, vol. 1. pp. 377-383, 2015.[Abstract]


The materials that has been proven as a light weight, durable and affordable is Aluminium and Magnesium. The amalgamation of high strength and low density property suits the wide range of engineering applications such as naval ships to go faster speeds and cargo ships carrying bigger payloads. Emerging technologies and advancements make Aluminium alloys as the best choice for military ships and automotives and Magnesium alloys as the best choice for automotive applications. These applications subject to an array of different types of varying loads in the marine and / or corrosive environment. Their environmental exposure and loading creates corrosion features such as pitting that produces crack initiation morphologies. Nucleation of these cracks followed by their growth under the influence of mechanical stress and corrosion leads to structural failure. This review paper deals with the corrosion and corrosion mechanisms of Aluminium and Magnesium alloys exposed to marine and corrosive environment, corrosion of welded structures and measures for enhancing the corrosion resistance. The development of new cast or wrought alloys, metal matrix composites and chemical agents (corrosion inhibitors) for enhancing the corrosion resistance are also discussed.

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2015

Vaira Vignesh R., Dr. Padmanaban R., and Thirumalini, S., “Reducing the environmental hazards by devising reduce recycle reuse system with hybrid black toner”, International Conference on Advances in Chemical Engineering, vol. 1. p. 4, 2015.[Abstract]


Photocopiers make use of Toner (powder) to form the latent electrical image on the electrostatically charged drum. The paper has to slide over the drum during Xerography process and hence it picks up the toner. Vague issues cause the non-picking of toner particles (approximately 10%) and they are left over the drum. This non-picked toner is termed as Waste Toner (WT). As it adversely affects the quality of proceeding copies, this has to be removed from the drum. A cleaning blade made of synthetic material removes WT formed over the surface of the drum and it gets deposited in the cleaner sump. This WT cannot be further reused as the quality of the copier and copy will also be reduced. Non biodegradable metal-plastic materials are used in the synthesis of toner. So dumping WT in open or in landfills leads to environmental hazards. The WT is mixed in proportion with Nano phase Carbon and original toner to get Hybrid Black Toner which can be used in photo copiers as an alternative toner. This research work deals with characterising the WT with respect to Original toner and Carbon Black Nano Powder to get an optimised copier quality with the usage of WT. This practice reduces the risk of environmental hazards of the WT if it is dumped in the landfills.

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2015

Dr. Padmanaban R., ,, V, M., and Basil, S., “A Study on Process Parameters and Tool Geometry Effect on Friction Stir Welding of AA1100 ”, International Conference on Emerging Trends in Engineering and Technology (ICET-2K15), vol. 10. K.N.S.K.College of Engineering, Kanyakumari Dt, Tamilnadu, INDIA, pp. 1266-1270, 2015.

2015

Dr. Padmanaban R., Cheeran, J. James, ,, and Bhaskar, V., “Design and Optimization of a Diesel Engine Connecting Rod”, International conference on Adaptive Technologies for Sustainable growth (ICATS- 2015) , vol. 10. pp. 23932-23935, 2015.

2014

Dr. Padmanaban R. and Selvaraj, J., “Exploring Quarry Dust as a Green Alternative to Silica sand for Casting in foundries”, IEEE Sponsored International Conference on Emerging Trends in Science, Engineering, Business and Disaster Management (ICBDM 2014). Noorul Islam University, Kumaracoil, Thuckalay, Tamilnadu, 2014.

2014

Dr. Padmanaban R., ,, ,, and K, G., “Simulated Annealing Based Parameter Optimization for Friction Stir Welding of Dissimilar Aluminum Alloys”, 12th Global Congress on Manufacturing and Management. VIT, Vellore, Tamilnadu, 2014.

2014

Dr. Ilangovan S. and Dr. Padmanaban R., “Effects of Ageing on Hardness and Wear Properties of Cu-9Ni-6Sn Cast Alloy”, International conference on advanced in design and manufacturing. 2014.

2014

Dr. Padmanaban R., V. Kishore, R., and Balusamy, V., “Numerical Simulation of Temperature Distribution and Material Flow During Friction Stir Welding of Dissimilar Aluminum Alloys”, 12th Global Congress on Manufacturing and Management , vol. 97. VIT, Vellore, Tamilnadu, 2014.

2010

Dr. Padmanaban R., ,, and Arun, J., “Finite Element Simulation of Thermal History during Friction Stir Welding of Dissimilar Aluminum Alloys AA 6061 and AA7075”, INCRAME 2010 . MGR University, Chennai., 2010.

2004

Dr. Padmanaban R. and .Sundar, M., “Recent Trends in Surface Engineering”, Emerging trends in surface engineering. VLB Janakiammal college of Engineering and Technology, 2004.

Publication Type: Conference Paper

Year of Publication Title

2017

R. Harikeshava, Srinivasan, M. S., Vaira Vignesh R., and Dr. Padmanaban R., “ANN model for predicting the intergranular corrosion susceptibility of friction stir processed aluminium alloy AA5083”, in Proceedings of the 2nd International Conference on Communication and Electronics Systems, ICCES 2017, 2017, vol. 2018-January, pp. 716-720.[Abstract]


Aluminium alloy AA5083 was subjected to friction stir processing with an objective to increase the intergranular corrosion resistance of the alloy. Experimental trials were performed by varying the friction stir process parameters namely Tool Rotation Speed, Tool Traverse Speed and Shoulder Diameters as per Taguchi's L18 orthogonal array. The base specimen and friction stir processed specimens were subjected to intergranular corrosion susceptibility test according to the standard ASTM G67-04. Artificial Neural Network model was developed with cascade forward propagation network architecture to predict the intergranular corrosion susceptibility of the friction stir processed specimens. The network was trained with 80% experimental data using Levenberg Marquardt algorithm and the remaining data was used for testing and validation. Least root mean squared error value and prediction error indicated high accuracy of the developed model. © 2017 IEEE.

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2017

A. R. Nair, Niranjhan, P., Abijith, M. N., Arivarasu, M., Manikandan, M., Dr. Padmanaban R., and Arivazhagan, N., “Potentiodynamic corrosion studies on laser beam welded austenitic stainless steel AISI 321”, in IOP Conference Series: Materials Science and Engineering, 2017, vol. 263.[Abstract]


In this study, the microstructure and corrosion characteristics of laser beam welded austenitic stainless plates has been studied. CO2 Laser beam produced defect free weldments in AISI 321 with no trace of heat affected zone. The microstructural studies revealed distributed ferrites in the weld zone. Potentio-dynamic polarization studies were carried out on the weldments in 5% NaCl environment in order to understand corrosion current, potential and rate. © 2017 Published under licence by IOP Publishing Ltd.

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2017

K. Chinnaraj and Dr. Padmanaban R., “Analytical Prediction of Residual Stresses in Cold Formed Steel Sections with Elastic - Perfectly Plastic Material Model”, in SAE Technical Paper, 2017.[Abstract]


The objective of this paper is to provide a reliable and robust mechanics based analytical approach for the accurate prediction of residual stresses in cold formed steel members. The forming residual stresses and associated equivalent plastic strains in cold formed corner sections are predicted with the assumption of elastic-perfectly plastic material model. The predicted analytical solution results are then compared with the existing analytical solution results. This work demonstrates that the exact estimation of forming residual stresses and equivalent plastic strains are possible with the inclusion of shift in neutral axis resulting from unequal thresholds of plasticity levels at the top and bottom surfaces of small radius corner sections. The predicted forming residual stresses and the associated equivalent plastic strains together define the initial conditions of corner sections for further non-linear structural behavior analysis of cold formed structures.

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2017

B. K. Murugan, Balusamy, V., and Dr. Padmanaban R., “Process parameter effects in the friction surfacing of MONEL over mild steel”, in Proceedings of 2017 11th International Conference on Intelligent Systems and Control, ISCO 2017, 2017, pp. 203-207.[Abstract]


MONEL has very good corrosion resistance and is used for cladding marine components. However, to avoid hot cracking, nickel is first overlayed on the substrate before MONEL is overlayed. Friction surfacing (FS) is a new solid state technique that could be used to do the same cladding process without any nickel overlay. In this study, MONEL K500 was deposited on AISI 1012 substrate using FS. Three parameters namely the spindle speed, axial load and the horizontal feed rate were varied at five levels and FS trials were conducted. Thickness of the coatings was measured for all the surfacing trials. Response surface methodology is utilized to develop a mathematical model for the thickness of the surfaced layer in terms of the three chosen parameters. The significance of the spindle speed, axial load and the horizontal feed rate in producing coatings with good bond integrity is investigated. © 2017 IEEE.

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2017

Vaira Vignesh R. and Dr. Padmanaban R., “Modelling tensile strength of friction stir welded aluminium alloy 1100 using fuzzy logic”, in Proceedings of 2017 11th International Conference on Intelligent Systems and Control, ISCO 2017, 2017, pp. 449-456.[Abstract]


Friction stir welding (FSW) is a promising technique in which joints with high strength and minimal defects can be realized by adopting optimum process parameters. The prominent parameters are tool rotation speed, welding speed, shoulder diameter and pin diameter of the tool. In this study Mamdani fuzzy system was used to generate the model for predicting and exploring the influence of FSW process parameters on tensile strength of AA1100 joints. The FSW trials are conducted at various levels of process parameters according to central composite design. The study proved that the process parameters had significant effect on the tensile strength of friction stir welded joints. Crest parabolic variation trend was observed in tensile strength of the joints, with respect to the interaction effects of TRS, WS and SD. Increase in pin diameter had positive effect in increasing the tensile strength of the joints, for any change in TRS, WS and SD. Maximum tensile strength of 72.4 MPa was obtained at tool rotation speed of 1050 rpm, welding speed of 60 mm/min, shoulder diameter of 18 mm and pin diameter of 6 mm. The methodology given in this paper delivers a useful tool to assess the tensile strength of friction stir welded AA1100. © 2017 IEEE.

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2016

Vaira Vignesh R. and Dr. Padmanaban R., “Investigations on the mechanical properties of MWCNT reinforced ASTM A48 by testing & mathematical modelling”, in Proceedings of the 10th International Conference on Intelligent Systems and Control, ISCO 2016, 2016.[Abstract]


Nano Technology, being the most hopeful technology of this century, plays a dynamic role in the development of Metal Matrix Nano Composites (MMNC). The high reactivity of Nano Phase Materials (NPH) can be outlined to their surface prominent characteristics. Enhancement mechanical or corrosion properties would be imperative for engineered materials to bear the forces from machines and environment. The scope of this research work is to increase the tensile strength of Grey Cast Iron ASTM A48 by reinforcing Multi Walled Carbon Nano Tube (MWCNT) in the matrix. © 2016 IEEE.

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2015

Dr. Padmanaban R., Muthukumaran, V., and Vighnesh, A., “Parameter Optimization for Friction Stir Welding AA1100”, in Advances in Mechanical Engineering, 2015.[Abstract]


Friction stir welding (FSW) has become a potential solid state joining technique with considerable advantages over conventional joining process. Defect-free friction stir welded joints with high joint strength are obtained when optimum process parameters are used. Although a large number of parameters govern the FSW process, the tool rotation speed, Welding speed and tool geometry are key parameters that influence the joint strength. In this work, a statistical model relating process parameters and the tensile strength (TS) of friction stir welded AA1100 joints is build using response surface methodology. The four independent variables are tool rotational speed (TRS), welding speed (WS), shoulder diameter (SD) and pin diameter (PD). Central Composite design is used and Analysis of Variance at 95% confidence level was applied to assess the adequacy of the developed model. Genetic algorithm is used for optimizing the parameters. The optimum process parameter values predicted using the genetic algorithm are as follows. Tool rotation speed: 1001.9 rpm; welding speed: 62 mm/min; shoulder diameter: 17.8 mm and pin diameter: 6.5 mm. The corresponding tensile strength of the joints is 73.1556 MPa

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Invited Talks

  • R. Padmanaban, Invited Speaker, "Thermomechanical analysis" in one week FDP on Finite element method and its applications, PSG College of Technology, Coimbatore, Tamilnadu, INDIA, June 16, 2016.
  • R. Padmanaban, Invited Speaker, "Application of FEM in Friction Stir Welding" ANNA University, Coimbatore, Tamilnadu, India, March 13,2015.
  • R. Padmanaban, Invited Speaker, "Introduction to FEM ", Karpagam Univeristy, Coimbatore, Tamilnadu, INDIA, September-29, 2014.
  • R. Padmanaban, Invited Speaker, "Friction Stir Welding – Process Modeling", Recent Trends in Manufacturing, Amrita Vishwa Vidyapeetham, Coimbatore, Tamilnadu, INDIA, March-28, 2014.
  • R. Padmanaban, Invited Speaker, "Introduction to Solid state Welding Process ", PSG College of Technology, Coimbatore, Tamilnadu, India, January-25, 2014.
  • R. Padmanaban, Invited Speaker, "Introduction to Gas Welding and Resistance Welding ", Dr. MCET, Pollachi, Coimbatore, Tamilnadu, India, March-23, 2013.
  • R. Padmanaban, Invited Speaker, Introduction to FEM , One day Workshop, PPG Institute of Technology Saravanampatty, Coimbatore, Tamilnadu, India, February-15, 2012.

Conferences/Workshops/Short-term courses (Organized)

  • Coordinated a Two-day workshop on Advanced Materials and Joining Processes, February 26 - 27, 2016 at Amrita Vishwa Vidyapeetham, Coimbatore. (84 Attendees)
  • Coordinated a Two-day workshop on Welding and NDT, March 31, and April 1, 2012. The workshop was organized in collaboration with IWS, Coimbatore Chapter.
  • Coordinated a Two-day workshop on Advanced Materials and Their Applications, March 20 – 21, 2014 at Amrita Vishwa Vidyapeetham, Coimbatore.
  • Conducted a certificate course during January- April 2015 on Introduction to ANSYS APDL for BTech Students of Amrita Vishwa Vidyapeetham, Ettimadai Campus.
  • Coordinated 3 days workshop on Engineering Critical Thinking with Practical Applications in association with Innovent Engg Services Pt. Ltd for students and scholars of Amrita Vishwa Vidyapeetham, Ettimadai Campus.
  • Coordinated 4 days Training on ANSYS & Workbench in association with Innovent Engg Services Pt. Ltd for students and scholars of Amrita Vishwa Vidyapeetham, Ettimadai Campus on Sept. 24, 2015 and October 2 - 4, 2015 at CAD Lab.

Seminars/Workshops Attended

  • 10 days GIAN Course on FEM Theory and Programming: With Applications to Solid Mechanics, Heat Transfer and Fluid Mechanics, 14-24 July 2016, IIT Hyderabad, Resource Person: Dr. J N Reddy, UTAM. (Grade: A)
  • TA101 Course & Written Exam, July 9-10, 2015 at Amrita Vishwa Vidyapeetham, Coimbatore.
  • Science Academies' Lecture Workshop on "Frontiers in Corrosion Engineering and Technology" February 12-13, 2016, Bannari Amman Institute of Technology, Sathyamangalam, Erode, Tamil Nadu. 
  • Short Term Training Programme on "Advanced Welding Technology" is conducted at Coimbatore Institute of Technology between, December 01 – 05, 2014.
  • International Conference on "Application of Lasers in Manufacturing" CALM 2015, September 09-10, 015, Pragati Maidan, New Delhi.
  • Faculty enablement program from Product Lifecycle and Engineering Solutions, June 21-29, 2010, Infosys Technologies Limited, Mysore DC.
  • AICTE STTP on "Engineering Design Principles and New Product development", Organised by Department of Engineering Design, IITM, June 30 to July 5, 2008.
  • Two Day Course on " Failure Analysis of Industrial Components", February 6-7, 2006, organised by Department of Metallurgical and Materials Engineering, IITM.
  • QIP STTP on "Semiconductor Manufacturing Processes" Conducted by Department of Chemical Engineering, IITM, May 23-27, 2005.
  • Short term course on "Gas Dynamics and Space Propulsion" at Sri Krishna College of Engineering and Technology, Coimbatore, May 2 – 7, 2005.
  • AICTE-ISTE Sponsored STTP on " Cleaner Technologies for Sustainable development", Department of Mechanical Engineering, Amrita Vishwa Vidyapeetham, Coimbatore.
  • BARC Sponsored Workshop on "High Performance Computing", December 22-27, 2004, organised by Amrita Vishwa Vidyapeetham, Coimbatore.
  • Training program on "MATLAB" organised by Department of Mechanical Engineering and Center for Excellence in Computational Engineering and Networking, Amrita Vishwa Vidyapeetham, Coimbatore, November 17 to December 9, 2004.
  • Two Weeks (May 16-29, 2004) AICTE Sponsored staff development program on "Performance Excellence for Engineering Teachers", conducted by PSG College of Technology, Coimbatore.
  • Short term course on "Hydraulics and Pneumatics Controls" at Sri Krishna College of Engineering and Technology, Coimbatore, November 24– 29, 2003.

Courses Handled

Undergraduates

  • Engineering Mechanics.
  • Material Science and Metallurgy.
  • Theory of Machines. ( Kinematics & Dynamics of Machines)
  • Introduction to Finite Element Method.
  • Machine Design.

Postgraduates

  • Mechanical Behavior of Engineering Materials
  • Fatigue, Fracture and Failure Analysis
  • Finite Element Analysis
  • Engineering Fracture Mechanics
  • Random processes and partial differential equations

Research Projects

  • Development of Braze Joint between Carbon-Carbon (C-C) Composites and Titanium Alloy Ti6Al4V. June 2017, submitted to ISRO RESPOND (Co PI). Sanctioned - Ongoing.

Research Supervision

List of Ph. D. Students

Current

  • Dhanesh S. (CB.EN.D*MEE16003), "Studies on Formability of Friction Stir Welded Tailor Welded Blanks", Department of Mechanical Engineering, Amrita Vishwa Vidyapeetham, Coimbatore. ( In Progress)
  • Ms. B. Subi (EN.D*MEE20007) "Studies on dissimilar materials joining", Department of Mechanical Engineering, Amrita Vishwa Vidyapeetham, Coimbatore. (Pursuing Course Work)

Completed

  • R. Vaira Vignesh (CB.EN.D*MEE15002), "Friction Stir Processing of Magnesium alloys and Synthesis of Surface Composites" Department of Mechanical Engineering, Amrita Vishwa Vidyapeetham, Coimbatore

Master’s Students

  1. Vikram, CB.EN.P2EDN18005 “Experimental and Numerical analysis of Crimping”, Thesis in fulfilment of Master of Technology degree from the School of Engineering, Amrita Vishwa Vidyapeetham University, Coimbatore, June 2020
  2. Sivachintharlu, CB.EN.P2EDN18016 “Experimental and numerical simulation of dissimilar FSW”, Thesis in fulfilment of Master of Technology degree from the School of Engineering, Amrita Vishwa Vidyapeetham University, Coimbatore, June 2020
  3. Mohan Bharathi, CB.EN.P2MFG17021  " Performance Evaluation of Thermally Sprayed Cr3C2-NiCr Coating under High Temperature Erosion" Thesis in fulfilment of Master of Technology degree from the School of Engineering, Amrita Vishwa Vidyapeetham University, Coimbatore, June 2019
  4. Mirza Abdul Hadi Baig CB.EN.P2MFG17020, " Finite Element Simulation of Laser Cladding and Corresponding Residual Stresses” " Thesis in fulfilment of Master of Technology degree from the School of Engineering, Amrita Vishwa Vidyapeetham University, Coimbatore, June 2019
  5. Abin Joe Alex, CB.EN.P2MFG17001 " Development of dissimilar joints between Aluminium and Copper by Friction Welding"Thesis in fulfilment of Master of Technology degree from the School of Engineering, Amrita Vishwa Vidyapeetham University, Coimbatore, June 2019
  6. Murali Manohar, CB.EN.P2EDN17022  " Characterization Of Az31-Nbc Surface Composite Fabricated By Friction Stir Processing" Thesis in fulfilment of Master of Technology degree from the School of Engineering, Amrita Vishwa Vidyapeetham University, Coimbatore, June 2019
  7. S Bhuvaneshwaran, CB.EN.P2EDN17036  "Finite Element Modelling for Predicting Spot Weld Fatigue Life" Thesis in fulfilment of Master of Technology degree from the School of Engineering, Amrita Vishwa Vidyapeetham University, Coimbatore, June 2019
  8. V Shrinaath, CB.EN.P2EDN17027  " Parametric Study of Spring-Back Effect in Three-Point Roll Bending Process" Thesis in fulfilment of Master of Technology degree from the School of Engineering, Amrita Vishwa Vidyapeetham University, Coimbatore, June 2019
  9. ArunSiddharth, CB.EN.P2EDN16001  " Experimental and Numerical studies on friction stir welded tailor welded blanks" Thesis in fulfilment of Master of Technology degree from the School of Engineering, Amrita Vishwa Vidyapeetham University, Coimbatore, July 2018
  10. Bharath V R, CB.EN.P2EDN15004, "Effect of Laser beam profile on Laser cladding process", Thesis in fulfilment of Master of Technology degree from the School of Engineering, Amrita Vishwa Vidyapeetham University, Coimbatore, July 2017
  11. Mobin M Mathew, CB.EN.P2MFG14011, " A Study on  the Micromachining of Molybdenum using Nanosecond and Femtosecond Lasers ", Thesis in fulfilment of Master of Technology degree from the School of Engineering, Amrita Vishwa Vidyapeetham University, Coimbatore, July 2016
  12. Pawan Kumar, CB.EN.P2EDN14009,  " Numerical and experimental investigation of butt joint using laser welding "", Thesis in fulfilment of Master of Technology degree from the School of Engineering, Amrita Vishwa Vidyapeetham University, Coimbatore, July 2016
  13. Priyanka, CB.EN.P2ATE14019, " Design and structural analysis of a test rig for a two stroke single cylinder diesel engine ", Thesis in fulfilment of Master of Technology degree from the School of Engineering, Amrita Vishwa Vidyapeetham University, Coimbatore, July 2016
  14. Karthick.K.P, CB.EN.P2EDN14004, "Design and development of High pressure Auto Drain for Filter Regulator unit", Thesis in fulfilment of Master of Technology degree from the School of Engineering, Amrita Vishwa Vidyapeetham University, Coimbatore, July 2016
  15. A. AbiramaSundar, CB.EN.P2EDN14001, " Design of 3/2 way solenoid valve with NACE compliance", Thesis in fulfilment of Master of Technology degree from the School of Engineering, Amrita Vishwa Vidyapeetham University, Coimbatore, July 2016
  16. "Effect of Process parameters on thermal history during Friction Stir Welding of AA1100 Aluminium alloy to AZ91D Magnesium alloy" Vighnesh Kumar, Thesis in fulfilment of Master of Technology degree from the School of Engineering, Amrita Vishwa Vidyapeetham University, Coimbatore, July 2015
  17. "Effect of Process parameters on friction stir spot welded joints of AHSS" A. MuthuKumaran, Thesis in fulfilment of Master of Technology degree from the School of Engineering, Amrita Vishwa Vidyapeetham University, Coimbatore, July 2015
  18. "Design and Analysis of Diesel Engine Connecting Rod and Crank " Jenson James, Thesis in fulfilment of Master of Technology degree from the School of Engineering, Amrita Vishwa Vidyapeetham University, Coimbatore, July 2015
  19. "Friction Stir Welding of Magnesium Alloy: Parametric Study and Optimization",  Krishna Prasad , Thesis in fulfilment of Master of Technology degree from the School of Engineering, Amrita Vishwa Vidyapeetham University, Coimbatore,  July 2014
  20. "Numerical Modeling of Friction stir welding of dissimilar materials " Nouranga K N, Thesis in fulfilment of Master of Technology degree from the School of Engineering, Amrita Vishwa Vidyapeetham University, Coimbatore, July 2013
  21. "CFD modelling of material flow during FSW " Arun, Thesis in fulfilment of Master of Technology degree from the School of Engineering, Amrita Vishwa Vidyapeetham University, Coimbatore, July 2011
  22. "Effect of process parameters on temp distribution and residual stress during dissimilar FSW AL alloys" vignesh, Thesis in fulfilment of Master of Technology degree from the School of Engineering, Amrita Vishwa Vidyapeetham University, Coimbatore, July 2011
  23. "Synthesis of copper Nano powders by vapour levitation Technique" Anusha Nalluri, Thesis in fulfillment of Master of Technology degree from the School of Engineering, Amrita Vishwa Vidyapeetham University, Coimbatore, July 2011

Bachelor’s Students

  1. Akshay Naidu (CB.EN.U4MEE15207 )“Optimizing the belt conveyer speed of bright annealing furnace” Project report in fulfilment of Bachelor of Technology degree from the School of Engineering, Amrita Vishwa Vidyapeetham University, Coimbatore, May 2019.
  2. Ashwin A (CB.EN.U4MEE15211), Chand Swaroop (CB.EN.U4MEE15214), Hari Lakshman R B (CB.EN.U4MEE15223), and Vignesh M (CB.EN.U4MEE15261) “ Corrosion and Tribological Behaviour of AA2024 Surface Composites Synthesised by Friction stir processing” Project report in fulfilment of Bachelor of Technology degree from the School of Engineering, Amrita Vishwa Vidyapeetham University, Coimbatore, May 2019.
  3. Harikeshava, Srihari, arjun and sreenath "FSP Effect of Friction Stir Processing on Corrosion and Tribological Properties of Aluminium Alloy AA5052" Project report in fulfilment of Bachelor of Technology degree from the School of Engineering, Amrita Vishwa Vidyapeetham University, Coimbatore, May 2018.
  4. Aadharsh M (CB.EN.U4MEE13104),Abijith m n (CB.EN.U4MEE13202) and Adithya Rajeev Nair (CB.EN.U4MEE13128),  "Comparison of Microstructure and mechanical properties of AA2219 welded using CMT,TIG and FSW" Project report in fulfilment of Bachelor of Technology degree from the School of Engineering, Amrita Vishwa Vidyapeetham University, Coimbatore, May 2017.
  5. "Microstructure, Properties and corrosion of  FSP  AA 5083 " M S SSairam (CB.EN.U4MEE12232), S Himavarsh (CB.EN.U4MEE12147), Akhilesh Kumar (CB.EN.U4MEE12207) and B Prasanth (CB.EN.U4MEE12216), Project report in fulfillment of Bachelor of Technology degree from the School of Engineering, Amrita Vishwa Vidyapeetham University, Coimbatore, May 2016.
  6. "Defect Detection during Friction Stir Welding using vibration signals " K. Sowmith et al. Project report in fulfillment of Bachelor of Technology degree from the School of Engineering, Amrita Vishwa Vidyapeetham University, Coimbatore, May 2015.
  7. "Friction Stir Processing of AZ91D Magnesium Alloy - Effect of Process  Parameters"  GopathNiranthar K (CB.EN.U4MEE11121), (CB.EN.U4MEE11148) SaikrishnaV,VigneshwaranK (CB.EN.U4MEE11162) and Sneha PriyaR (CB.EN.U4MEE11511), Project report in fulfillment of Bachelor of Technology degree from the School of Engineering, Amrita Vishwa Vidyapeetham University, Coimbatore, May 2015.
  8. "Friction Surfacing of Monel K500 over Carbon Steel "  KiruthiMurugan and Adithan, Project report in fulfilment of Bachelor of Technology degree from the School of Engineering, Amrita Vishwa Vidyapeetham University, Coimbatore, May 2014.
  9. "Optimization of Friction Stir Welding of Magnesium Alloy AZ91D " A. Govindreddy et al. Project report in fulfilment of Bachelor of Technology degree from the School of Engineering, Amrita Vishwa Vidyapeetham University, Coimbatore, May 2014.

Journal Review Activities

Reviewed technical manuscripts for the following International Journals

  • Journal of Alloys and Compounds- Elsevier
  • International Journal of Advanced Manufacturing Technology - Springer
  • Multidisciplinary Modelling in Materials and Structures – Emerald Insight
  • Engineering Review-University of Rejika
  • Journal of Intelligent Manufacturing – Springer
  • Silicon – Springer
  • Materials and Metallurgical Transactions A – Springer
  • Materials and Manufacturing Process – Taylor & Francis
  • Anti-corrosion methods and materials
  • Material Today Proceedings

Key Responsibilities at Amrita Vishwa Vidyapeetham

  • Batch Coordinator – 2018 Batch
  • CAD Lab In charge
  • TAG Lead – Lightweight materials processing and characterization group

Membership in Professional Bodies

  • Life Member- ISTE (LM 36915),
  • Life Member - IWS (L00 480)
  • Member – IACSIT (80342931)
  • Founder Life Member – SFA (FLM-SFA-0371)