Microstructure evolution, mechanical response and strengthening models for TA15 titanium alloy during thermal processes: A brief review

TA15 titanium alloy is widely used in aerospace industry in terms of its high specific strength, good thermal stability, and excellent corrosion resistance. To further improve its mechanical properties, thermal deformation combined with heat treatment is always used, during which the microstructure evolution and mechanical response are absolutely complex leading to the difficulty in control of final mechanical properties. Therefore, in-depth research on the relationship between microstructure and mechanical response of TA15 titanium alloy during these processes is of great significance. At present, less relevant review has been reported. In this article, the effects of process parameters such as heating temperature, strain rate, deformation amount, deformation mode, deformation path, cooling method and soaking time on the microstructure and mechanical properties of TA15 alloy, namely tensile performance and damage tolerance properties have been discussed. In addition, some strengthening models suitable for TA15 titanium alloy have been analyzed. In conclusion, different microstructure morphologies formed in various processing processes will display diverse mechanical performances in which the direct relationship between the yield strength and microstructure morphology can be established through distinct calculation models but with some limitations. So, in future works, microstructure and mechanical properties should be optimized further through adjusting processing parameters. Moreover, strengthening models remains to be modified by adopting more accurate statistical methods and considering more factors. Finally, establishing the relationship between damage tolerance properties such as fracture toughness, creep performance and LCF property and microstructure features should be considered more for TA15 alloy.