This investigation highlights the influence of plasma nitriding on titanium surface in order to improve its interfacial adhesion strength with epoxy and epoxy nanocomposites adhesive. Surface energy of titanium increases considerably due to plasma nitriding implantation. X-ray photoelectron spectroscopy studies indicate the formation of various titanium nitrides, which are responsible for the increase in surface polarity. A reduction in equilibrium contact angle improve wetting on the surface and proper intimacy of the adhesive layer with two joining titanium surfaces. The atomic force microscopic study indicates smoothening of treated titanium surface. Thus, a greater surface area of contact with the adhesive layer helps uniform splitting of adhesive over the two titanium surfaces. A further improvement in bond strength is achieved on incorporation of 5% nanosilicate as reinforcement within the adhesive.
S. Ahmed, Chakrabarty, D., Shantanu Bhowmik, Mukherjee, S., and Rane, R., “Plasma nitriding on titanium surface for adhesion promotion”, Surface Engineering, vol. 31, pp. 616–622, 2015.