固溶时效对Ti-6Cr-5V-5Mo-4Al-1Nb合金组织和力学性能的影响

Effect of Solution and Aging Heat Treatment on Microstructure and Mechanical Properties of Ti-6Cr-5V-5Mo-4Al-1Nb Alloy

摘要:

研究了固溶温度、时效温度、时效时间对Ti-6Cr-5V-5Mo-4Al-1Nb(Ti-65541)合金显微组织与力学性能的影响。结果表明,在β相变点以上固溶并时效后,合金中析出细小的次生α相,初生α相完全消失;在较低温度固溶并时效后,次生α相和初生α相同时存在。时效温度对合金强度和塑性的影响最为显著,固溶温度次之,时效时间的影响最弱。随着时效温度的升高,合金的抗拉强度和屈服强度降低,塑性提高。随着固溶温度的提高,合金的强度提高,塑性降低。随着时效时间的延长,合金强度和塑性总体呈降低趋势。在740～760℃范围内固溶处理,在540～580℃范围内时效且时效时间在4～6 h内,可获得综合性能优异的Ti-65541合金。

Abstract:

The effects of heat treatment parameters on the microstructure and mechanical properties of Ti-6 Cr-5 V-5 Mo-4 Al-1 Nb( Ti-65541) alloy were investigated,such as solution temperature,aging temperature and time. The results indicate that the fine secondary α phase precipitates in the matrix,while the primary α phase disappears completely after solution above the β phase transition temperature and aging. However,the secondary α phase and primary α phase exist simultaneously after solid solution at lower temperature and aging. Besides,the aging temperature has the most significant influence on its strength and plasticity,followed by solution temperature,and the aging time has the weakest effect. With the increase of aging temperature,the tensile strength and yield strength of Ti-65541 alloy decrease,and the plasticity increases. As the solution temperature increases,the strength increases and plasticity decreases. While with the extension of aging time,the strength and plasticity of Ti-65541 alloy generally decrease. The perfect comprehensive performance can be obtained after solution in the temperature range of 740 ～ 760 ℃ and aging treatment in the temperature range of 540 ～ 580 ℃ with 4 ～ 6 h.