Course

Unit 1

Properties of X-rays and Description of Crystals
Learning Objectives
Introduction to X-rays and microstructures of common solids

Production and detection of X-rays, Directions and intensities of diffracted beams, Detectors and measuring intensities of X-rays, Methods of X-ray diffraction, Penetration of X-rays, Grain size, Particle size and Crystal perfection and Orientation.

Unit 2

X-ray Analysis
Learning Objectives
Understand the methods of using X-rays to construct phase diagrams distinguish reactions and measure compositions of alloys

Determination of phase diagrams, Order-disorder phase transitions, Chemical analysis by diffraction: Hanawalt method, Direct comparison and Internal standard methods, Chemical analysis by Fluorescence and Absorption.

Unit 3

Precise Lattice Parameter Measurements
Learning Objectives
Learn to use curve fitting methods to measure lattice parameters precisely; Introduction to full pattern refinement methods

Rietveld refinement method, General methods of precise lattice parameter measurement: Least Squares method, Cohen’s method, Calibration method, Hugo Rietveld’s method of full pattern refinement, Introduction and practice of refinement using the Full Proof software (open source).

Unit 4

Transmission Electron Microscopy
Learning Objectives
Introduction to scattering by electrons; instrumentation and imaging modes in the TEM including CBED technique

Comparison of scattering by electrons and X-rays, Elastic and inelastic electron scattering, Basic instrumentation and imaging modes in TEM, Obtaining and indexing parallel beam electron diffraction patterns, Kikuchi lines and use of Convergent Beam Electron Diffraction (CBED) techniques.

Unit 5

Phase Contrast Imaging and HR-TEM
Learning Objectives
Learn to use the TEM to image defects (line defects and planar defects); Image formation in the HRTEM

Different contrast mechanisms in the TEM: Amplitude, Mass-thickness, Z-contrast, STEM diffraction contrast, Analysing defects: Two beam condition, Weak beam dark field imaging, Thickness and bending effects, Planar defects, Strain field imaging, High resolution TEM.

Prerequisites: The student is expected to have covered topics in basic solid-state physics and geometric ray-optics.

Course Objectives:
1. Introduce the concept of diffraction with X-rays and electrons to the students.
2. Briefly describe the use of X-rays to determine crystal structures, construct phase diagrams and analyse phase transitions and particle agglomeration in materials; a topic on refinement methods is also introduced.
3. Introduce the student to conventional transmission electron microscopy (TEM) and its utility to analyse crystal structures, analyse line and planar defects and grain boundaries in materials.
4. Qualitative treatment of phase contrast (High Resolution) TEM will be introduced to students.

Course Outcomes:
CO1: Understand fundamental concepts of X-ray diffraction
CO2: Apply diffraction techniques to study materials
CO3: Understand electron diffraction and the instrumentation of the TEM
CO4: Understand how to index 2D electron diffraction patterns.

Skills: Problem solving skills and analytical thinking skills will be enhanced. Software tools will be introduced to the student.

CO-PO Mapping

1. B. D. Cullity and S. R. Stock, “Elements of X-ray Diffraction”, Third Edition, Pearson Education India, 2014.
2. Vitalij K. Pecharsky, Peter Y. Zavalij, “Fundamentals of Powder Diffraction and Structural Characterization of Materials”, Second Edition, Springer, Boston, MA, 2005.
3. David B. Williams and C. Barry Carter, Transmission Electron Microscopy – A Textbook for Materials Science, Second Edition, Springer, 2011.

Justification for CO-PO Mapping