Optimisation of wear behaviour of heat treated Ti-6Al-4V alloy by response surface methodology

Titanium alloys are extensively used in various fields of engineering, medicine, aerospace and marine due to their excellent mechanical properties. The response of the Ti alloys for its wear resistance is very poor. In this research the wear behaviour of the Ti alloys is improved by the heat treatment process. In this research, the implant material is subjected to heat treatment above its transformation temperature (950°C) followed by cooling in furnace. These specimens were further aged at 550°C for three hours and then water quenched. The property of poor wear resistance can be improved by changing the microstructure of the alloy where the formation martensitic structure (acicular α or retained β) is resulted. The wear test was conducted using the pin-on-disk, with varying parameters of the applied load (10-50 N), speed (100-500 rpm) and time (5-25 min). Scanning electron micrographs (SEM) exhibit the wear scars and worn surfaces of the tested specimens. The optimum parameters were optimised by the response surface methodology and some useful conclusions were made.