固溶-时效对粉末成形TC4钛合金显微组织和力学性能的影响  

Effect of Solution and Aging Treatments on Microstructure and Mechanical Properties of Powder Forming TC4 Titanium Alloy

作　　者：刘莹莹 黄志涛 Liu Yingying;Huang Zhitao(AVIC Manufacturing Technology Institute,Beijing 100024,China)

机构地区：[1]中国航空制造技术研究院,北京100024

出　　处：《钛工业进展》2021年第6期24-30,共7页Titanium Industry Progress

摘　　要：研究了固溶温度、冷却方式以及时效温度对粉末成形TC4钛合金相组成、微观组织以及力学性能的影响,分析了固溶-时效热处理过程中微观组织变化及析出强化机制。结果表明,在两相区固溶处理,随固溶温度的升高,初生α相含量不断减少;单相区固溶处理后,初生α相全部溶解,析出相呈片层状;固溶时采用水冷可获得α+α′组织,时效过程中马氏体分解形成的次生弥散相实现合金强化。粉末成形TC4钛合金经950℃/1 h/WQ+500℃/4 h/AC热处理后,综合性能匹配良好,抗拉强度为1231 MPa,屈服强度为1126 MPa,延伸率为10.75%。Effects of solution temperature,cooling method and aging temperature on the phase composition,microstructure and mechanical properties of powder forming TC4 titanium alloy were studied.The change of microstructure and precipitation strengthening mechanism during the solution and aging heat treatment were analyzed.The results show that the content of primaryαphase decreases with the increase of solution temperature in two phase region,the primaryαphase is completely dissolved after solution inβphase region,and the precipitated phase is lamellar.Theα+α′phase can be obtained by water quenching and the secondary dispersion phase formed by martensite decomposition during aging process realizes alloy strengthening.After heat treated by 950℃/1 h/WQ+500℃/4 h/AC,the comprehensive properties of powder forming TC4 titanium alloy match well,with tensile strength of 1231 MPa,yield strength of 1126 MPa and elongation of 10.75%.

关 键 词：TC4钛合金 粉末成形 热处理 显微组织 力学性能 

分 类 号：TG166.5[金属学及工艺—热处理] TG146.23[金属学及工艺—金属学]