Stress Induced Martensitic Transformation of As-cast TB6 Titanium Alloy During Hot Process [铸态TB6钛合金热变形过程中应力诱发马氏体相变]

作者：Ouyang D.; Cui X.^*; Lu S.; Du H.

来源：Rare Metal Materials and Engineering, 2020, 49(11): 3776-3781.

• As-cast TB6 titanium alloy
• Hot process
• Martensite

Hot compression tests of as-cast TB6 titanium alloy were performed at the temperature of 800~1150℃ and the strain rate of 0.001~10 s-1 to examine microstructure evolution associated with stress induced martensite (SIM). The results reveal the occurrence of the SIM with the dendritic morphology in the present alloy during hot compression process. The orthorhombic structure of SIM was confirmed for the alloy. It is found that the SIM nucleates both in the β grain interior and at grain boundary. The alloy composition uniformity and internal stress are strongly dominated by strain rate and deformation temperature, which are responsible for the amounts of SIM. The content of SIM at different strain rates is related to the temperature ranges. More SIM appear at the strain rate of 0.1 s-1 for the temperature of 800~900℃, at 0.01 and 1 s-1 for the temperature of 900~1000℃, at the strain rate of 1 s-1 for the temperature of above 1000℃. 50% martensite can be obtained at an optimal combination of the temperature of 925℃ and the strain rate of 1 s-1.