TB9钛合金棒材组织遗传效应与性能

Effect of Texture Inheritance on Microstructure of Beta C Titanium Alloy

摘要:

以TB9钛合金为研究对象，对比分析了TB9铸锭不同部位在热加工过程中的组织差异，揭示了TB9钛合金棒材的组织遗传效应及其对性能的影响。结果表明，TB9钛合金铸锭可以分为底部沿轴向的柱状晶区，芯部的等轴晶区，边部与轴向呈45°的柱状晶区。其中铸锭底部的柱状晶具有较强的<100>织构，在随后的锻造和热轧过程中，<100>织构的柱状晶难以破碎，具有很强的遗传性，致使最终棒材尾部残留粗大的柱状晶结构，时效后抗拉强度仅为987 MPa。铸锭芯部等轴晶区没有明显的择优取向，最终制备的棒材晶粒细小，组织均匀，棒材的性能优良，抗拉强度可达1290 MPa。

Abstract:

The microstructure difference between different parts of the TB9 ingot during hot-working was analyzed, and the microstructure inheritance effect on microstructure evolution and properties of TB9 bar was revealed. The results show that the TB9 ingot can be divided into axial columnar crystal zone at the bottom, equiaxed crystal zone in the core, and columnar crystal zone inclined 45° to the axial direction at the edge. The columnar crystal at the bottom of the ingot with a strong <100> texture is difficult to break and has a strong heredity, resulting in the residual coarse columnar crystal in corresponding bar after hot rolling, and the tensile strength of the bar after aging is only 987 MPa. The equiaxed crystal zone in the core of the ingot has no obvious preferred orientation, and the corresponding bar after hot rolling has fine equiaxed grains with a tensile strength of 1290 MPa.