Effect of Triple Heat Treatment on Basket-Weave Structure and Tensile Properties of TC21 Titanium Alloy

作者：Zhou Jianwei; Sun Qianjiang^*; Peng Jiahao; Xu Hao

来源：RARE METAL MATERIALS AND ENGINEERING, 2022, 51(9): 3353-3359.

• TC21 titanium alloy
• triple heat treatment
• basket-weave structure
• tensile properties

The effect of heat treatment temperature and cooling rate on the basket-weave structure and tensile properties of TC21 titanium alloy was studied by triple heat treatment experiments. The results indicate that the microstructure of TC21 alloy presents a typical basket-weave structure, which is achieved by high temperature (990 degrees C) solid solution in the beta single-phase region, and then through high temperature (870 similar to 910 degrees C) aging in the (alpha+beta) phase region and low temperature (590 degrees C) aging. With the increase of the second heat treatment temperature, the content and length of the flake alpha phase decrease significantly, and the thickness of the flake a phase increases slightly, the strength of the alloy increases, the ductility decreases. After being treated with different cooling rates, the microstructure of TC21 titanium alloy consists of a phase, beta phase and alpha' martensite in both water cooling and air cooling samples, but only a phase and beta phase are identified in furnace cooled sample. Compared with the tensile properties of the three samples, the water cooling and air cooling samples show better strength and poorer ductility, While furnace cooling samples show good ductility and poor strength. The better triple heat treatment process for TC21 alloy is 990 degrees C/1 h, AC+870 degrees C/1 h, AC+590 degrees C/4 h, AC.

• 单位
  南昌航空大学