Ti6321钛合金再加载力学行为研究

Research on Reloading Mechanical Behavior of Ti6321 Titanium Alloy

摘要:

对经轻气炮预冲击的Ti6321双态组织样品进行准静态压缩和动态压缩再加载试验,探究冲击后其力学性能的变化。利用光学显微镜(OM)和透射电子显微镜(TEM)对其微观组织演化进行观察并分析。结果表明,经预冲击后的Ti6321合金的静动态屈服强度、平均流变应力较原始样品有所升高,但断裂应变、冲击吸收功明显下降,且经过预冲击的样品经动态再加载后更易出现绝热剪切破坏。TEM结果表明,经轻气炮预冲击过后的样品内部有孪晶生成,从而导致了Ti6321钛合金表现出冲击波强化效应。

Abstract:

The quasi-static and dynamic reload compression tests were conducted to explore the changes in mechanical properties of Ti6321 alloy bimodal structure after preshock. The optical microscopy (OM) and transmission electron microscopy (TEM) were used to observe and analyze the microstructures. The results show that the static and dynamic yield strength and average flow stress of Ti6321 alloy after pre-shock are higher than those of the original sample, but the fracture strain and impact absorption energy are significantly reduced, and the preshock sample is more likely to appear an adiabatic shear failure after SHPB loading. TEM results showed that twins were formed inside the sample after the preshock of the light gas gun, which caused the Ti6321 titanium alloy to exhibit a shock wave strengthening effect.