热处理工艺对TC4钛合金组织和力学性能的影响  

Effect of heat treatment process on microstructure and mechanical properties of TC4 titanium alloy

作　　者：鲍学淳 程礼[1,2] 陈煊 鲁凯举[1] Bao Xuechun;Cheng Li;Chen Xuan;Lu Kaiju(Aeronautics Engineering College,Air Force Engineering University,Xi'an Shaanxi 710038 ,China;Co-Innovation Center for Advanced Aero-Engine,Beijing 100191)

机构地区：[1]空军工程大学航空工程学院,陕西西安710038 [2]先进航空发动机协同创新中心,北京100191

出　　处：《金属热处理》2019年第6期137-140,共4页Heat Treatment of Metals

基　　金：国家重点基础研究发展计划(973计划)(2015CB057400)

摘　　要：通过光学显微镜、扫描电镜、维氏硬度计和拉伸试验机等手段研究了不同热处理工艺对TC4钛合金组织和性能的影响。结果表明:热处理工艺对TC4钛合金的晶粒形态、尺寸和各相占比产生很大影响。经920℃固溶1 h后空冷加530℃时效4 h后空冷获得的双态组织和700℃退火2 h后空冷获得的等轴组织的抗拉强度分别高达986 MPa和987 MPa,且两种组织均具有良好的塑性,经1030℃固溶1 h后空冷加530℃时效4 h后空冷获得的魏氏体组织的抗拉强度低(949 MPa)、塑性差;魏氏体组织的断口SEM照片表现为脆性穿晶断裂为主导,双态组织和等轴组织表现为韧性断裂。魏氏体组织的硬度值最高,等轴组织的硬度值最低,两者的维氏硬度值分别为358 HV0.1和331 HV0.1。The effect of different heat treatments on the microstructure and properties of TC4 titanium alloy were studied by means of optical microscopy,scanning electron microscopy,Vickers hardness tester and tensile testing machine.The results show that the grain morphology,grain size and proportion of each phase of TC4 titanium alloy are greatly affected by heat treatment process.The tensile strength of the duplex microstructure solution treated at 920℃for 1 h and air cooled,and then aged at 530℃for 4 h and air cooled,andequiaxed microstructure solution treated at 700℃for 2 h and then air cooling reach 986 MPa and 987 MPa,respectively,and the plasticity of both microstructures are good,while the tensile strength of the widmanstatten microstructure solution treated at 1030℃for 1 h and air cooled,and then aged at 530℃for 4 h and air cooled are low(949 MPa)and plasticity is poor.It is showed that the fracture SEM micrographs for widmanstatten microstructure give priority to the brittle transgranular fracture,and the duplex and equiaxed microstructure are ductile fracture.The hardness of the widmanstatten microstructure is the highest,but he hardness of equiaxed microstructure is the lowest.The Vickers hardness values of both microstructure are 358 HV0.1 and 331 HV0.1,respectively.

关 键 词：TC4钛合金 热处理 显微组织 拉伸性能 SEM分析 硬度 

分 类 号：TG156[金属学及工艺—热处理]