热处理工艺对TC4钛合金组织和性能的影响

Effects of Heat Treatment Process on Microstructure and Mechanical Properties of TC4 Alloy

研究了不同热处理条件下TC4合金的微观组织和力学性能。结果表明,退火处理后,组织由α相与α相晶粒间弥散的细小等轴状β所组成,强度、硬度降低,韧性提高;在TC4两相区进行固溶处理,初生α相含量减少,形成了针状的马氏体α''组织,β相则由细小的等轴状逐渐转变为层片状,使得合金强度、硬度提高,伸长率呈下降趋势;时效处理后,针状的马氏体α''和亚稳态的β相将发生分解,转变成稳定的弥散的α相和β相,使合金综合性能得到改善。

The microstructure and mechanical properties of TC4 alloy under different heat treatment conditions were studied.The results show that the microstructure of TC4 alloy consists of α and fine equiaxial β after annealing.The strength and hardness decreases,while the ductility increases.After solution hardening,the primary phase α reduces and needle-like martensites α＇＇ formes.The fine equiaxial β changes into laminas gradually.Then the strength and hardness increases,the ductility decreases.The needle-like martensites α＇＇ and metastable β will break down into disperse α and β after solution hardening and aging.The combination properties of the alloy were improved.