Property enhancement and microstructural evolution during thermo-mechanical processing of titanium alloys: A review

Thermo-mechanical processing (TMP) offers bi-fold advantages through development of new components as well as aids in improvement in mechanical properties via control of microstructure. The objective of present study is to review titanium alloys’ thermo-mechanical processing (TMP), high temperature deformation processes, and microstructure control during thermo-mechanical processing. It was observed that employing different heat treatment procedures on titanium alloys resulted in improved mechanical properties with variable microstructure evolution including lamellar, bimodal, equiaxed, acicular, basket-weave and widmanstätten. Different microstructure is dependant several parameters such as Homogenization temperature, Heating rate, Holding time, Cooling rate, Extent of pre-homogenization and post homogenization deformation, Recrystallization temperature etc. Different microstructure is also a result of cooling rate and cooling medium. It has been shown that titanium alloys chilled in water exhibit the highest levels of hardness because martensite forms quickly, followed by cooling in air and a furnace. The development of titanium alloy presents significant opportunities for space applications, healthcare and automobile industries, and surface engineering. Thermomechanical processing of titanium alloys considerably improves their microstructure and mechanical characteristics. This study examines the impact of thermomechanical processing on the microstructure and mechanical properties of titanium alloys.