Ti-6Al-4V合金绝热剪切敏感性与临界破碎速度关系研究

Study on the Relationship between Adiabatic Shear Susceptivity and Critical Fracture Velocity for Ti-6Al-4V Alloy

利用应力塌陷发生的临界应变作为参量对比了Ti-6Al-4V合金的4种典型组织的绝热剪切敏感性,同时利用Taylor杆实验技术测定了其临界破碎速度,分析了钛合金绝热剪切敏感性与临界破碎速度关系。结果表明:不同组织的Ti-6Al-4V合金绝热剪切敏感性存在差异,实验涉及到的4种组织中双态组织最难于发生绝热剪切破坏;在Taylor杆高速冲击条件下,4种不同组织的Ti-6Al-4V合金均由于发生绝热剪切变形而导致破坏,并且临界破碎速度与应力塌陷临界应变成正比。

Adiabatic shear susceptivity of four typical structure for Ti-6Al-4V alloy was evaluated by critical strain which stress collapse takes place, and the critical fracture velocity was tested by Taylor bar technology. Also the relationship between adiabatic shear susceptivity and critical fracture velocity was explored. The results show that there are an adiabatic shear susceptivity differences among four kinds of microstructure in Ti-6Al-4V, in which the bimodal microstructure is of lowest adiabatic shear susceptivity; under the condition of Taylor bar impact at top speed, the adiabatic shear deformation will result in the rupture of four kinds of structure in Ti-6Al-4V, and the critical fracture velocity is in proportion to critical strain.