固溶-时效对TC4钛合金显微组织和力学性能的影响

Effect of Solution-aging on Microstructure and Mechanical Properties of TC4 Titanium Alloy

采用不同制度固溶-时效的热处理方式对TC4钛合金棒材进行热处理,并通过金相观察､力学性能检测研究了固溶-时效对钛合金棒材的微观组织和力学性能的影响。金相观察发现,固溶后大部分α相转变为亚稳相β相､α′相和α″相,时效处理后将亚稳相转变为细小稳定等轴组织与片层组织。力学性能检测结果表明:固溶水淬延迟时间在10 s,时效温度和时间在550℃/300 min(空冷),强度达到了最大值,因此954℃/60 min(水淬,10 s)+550℃/300 min(空冷)为最佳固溶-时效热处理制度。

The TC4 titanium alloy bars were heat treated with different solid solution and aging heat treatment methods,and the effect of solid solution and aging on the microstructure and mechanical properties of titanium alloy bars was studied by metallographic observation and mechanical property test.It is known from the metallographic examination that after solid solution,most of theαphase transformed into metastableβphase,α′phase andα″phase,and then aging treatment transformed the metastable phase into fine stable equiaxed structure and lamellar structure.The results show that:the solution water quenching delay time was 10 s,the aging temperature and time were 550℃/300 min(AC),the strength reaches the maximum,so 954℃/60 min(WQ,10 s)+550℃/300 min(AC)that was the best solid solution and aging heat treatment methods.