烧结温度对Micro-FAST制备TiAl合金组织和性能的影响

为解决TiAl合金成形困难的问题,以Ti、Al元素粉末为原料,采用Micro-FAST制备Ti-47Al合金,研究不同温度(7001050℃)对TiAl合金组织和性能的影响,并且探究了烧结过程中颗粒的迁移机制。结果表明,700℃烧结时不能形成典型组织,主要相为TiAl3;800℃及以上烧结时为岛状组织,主要相为大量的TiAl和少量的Ti3Al;在1050℃烧结时具有最佳的综合力学性能。烧结过程由多种扩散机制共同控制,随着烧结的进行,依次为蒸发-凝聚、体积扩散、晶界扩散和表面扩散。

Effects of Sintering Temperatures on Microstructures and Properties of TiAl Alloy by Micro-FAST

In order to solve the problem of forming difficulty of TiAl alloy,Ti-47 Al alloy was sintered by Micro-FAST using Ti and Al element powders as raw materials.The effects of temperatures(700~1050°C)on the microstructures and properties of TiAl alloy were studied,and the migration mechanisms of particles during sintering were investigated.The results show that typical microstructures could not be formed during the sintering at 700°C,and the main phase was TiAl3.When sintering at 800°C and above,the island structure was formed,and the Ti-47 Al alloy was mainly composed of TiAl and a small amount of Ti3 Al.The alloy sintered at 1050°C has the best comprehensive mechanical properties.The sintering process was controlled by several diffusion mechanisms.As the sintering proceeds,evaporation condensation,volume diffusion,grain boundary diffusion and surface diffusion occurred in sequence.