热处理对WSTi3515S合金组织和性能的影响

Effect of Heat Treatment on Microstructure and Mechanical Properties of WSTi3515S Alloy

摘要:

对WSTi3515S合金不同热处理和热暴露条件下的组织和力学性能进行了研究，结果表明，850 ℃以下热处理工艺对合金的组织和室温力学性能几乎没有影响，950 ℃热处理后虽然合金组织形态发生明显变化，但室温力学性能没有明显变化，表明WSTi3515S合金具有良好的组织和性能稳定性。不同热处理试样经过570 ℃热暴露后，合金强度升高，延伸率显著下降，热暴露过程中，析出的第二相很少，并且大都产生在晶界，这些晶界析出物是合金热暴露塑性显著降低的主要原因

Abstract:

The microstructure and mechanical properties of WSTi3515S alloy after various heat treatments and thermal exposure treatments were researched. The results indicate that different heat treatments below 850 oC have little effect on microstructure and mechanical properties of the alloy. When the heat treatment temperature is 950 oC, the microstructure of the alloy obviously changes; however, the room-temperature mechanical properties have no change, which indicates that WSTi3515S alloy holds better microstructure and performance stability. After the heat treated samples are thermal exposed at 570 oC for 100 h, the strength of the alloy increases and the elongation sharply decreases. During the thermal exposure process, there is a small quality of precipitations in the alloy and they mainly distribute at grain boundaries. The precipitation at the grain boundaries is the main reason for the decreased elongation of the alloy after thermal exposure