TC4钛合金连续热变形过程中的组织及取向演变

Microstructure and texture evolution of TC4 titanium alloy during continuous hot deformation process

利用扫描电镜和背散射电子衍射技术等分析方法,研究了TC4钛合金在连续热变形过程中的组织和取向演化。结果表明:随着应变量的增加,初生α相所占比例明显降低;长条状初生α片层发生球化,尺寸也有一定程度的下降,片层β相厚度减小;Burgers取向关系偏差角度变大。进一步的半定量分析表明,在真应变ε为0.5~0.6时界面能达到最大值,共格界面消失。与此同时,Burgers取向关系的角度偏差也在相同的应变量范围下达到15°,界面完成由半共格界面向非共格界面过渡。

Microstructure and texture evolution of TC4 Titanium alloy during continuous hot deformation were investigated by electron back scattering diffraetometry（EBSD） technique and scanning electron microscopy（SEM）. The results indicate that the fraction of the primary α phase decreases significantly with the increasing of the strain, and the lamella of elongated primary α gets spheroidized with the size reduce for a certain degree, while the thickness of famelia β phase decreases and Burgers orientation deviation angle increases. Further analysis also shows that interface energy of α/β reaches the maximum and coherent interface disappears when true strain is loaded to 0.5- 0.6. Simultaneously, Burgers orientation deviation angle becomes as high as 15°, transforming the semi-coherent interfaces into incoherent ones.