微观组织对TC29钛合金强度及塑韧性的影响  

Influence of Microstructure on Strength and Ductility of TC29 Titanium Alloy

作　　者：李思兰[1] 李倩[1] 张思远[1] 毛成亮 张冰洁 贾蔚菊[1] Li Silan;Li Qian;Zhang Siyuan;Mao Chengliang;Zhang Bingjie;Jia Weiju(Northwest Institute for Nonferrous Metal Research,Xi’an 710016,China)

机构地区：[1]西北有色金属研究院,陕西西安710016

出　　处：《钛工业进展》2024年第6期7-14,共8页Titanium Industry Progress

基　　金：陕西省重点研发计划项目(2022GY-387);陕西省重点研发计划项目(2023-YBGY-443)。

摘　　要：在两相区及单相区分别对TC29钛合金进行变形处理,再通过退火和固溶时效2种不同制度进行热处理,研究不同工艺及微观组织对TC29钛合金强度及塑韧性的影响。结果表明:合金经两相区变形,再经退火或固溶时效处理后,呈现典型的双态组织形貌。两相区变形再经850℃固溶及时效处理后,基体中微米尺度的次生α相消失,同时析出大量纳米尺度的次生α相。单相区变形再经固溶时效处理后主要为片层组织,基体中析出大量纳米尺度的次生α相。固溶时效处理的两相区变形试样,随固溶温度的升高,室温抗拉强度增大,最高可达1471MPa。退火处理的两相区变形试样的冲击韧度最大,可达58.8 J/cm^(2)。固溶时效处理的单相区变形试样的断裂韧度最高,达到73 MPa·m^(1/2)。两相区变形后的断裂韧度试样呈现出准解理状断口,断裂方式主要以脆性穿晶断裂为主,可见少量孔洞。单相区变形后的断裂韧度试样呈现解理及韧窝混合状断口,存在大量撕裂棱、孔洞及二次裂纹。The TC29 titanium alloy was subjected to deformation treatment in the two-phase and single-phase regions respectively,followed by two kinds of heat treatments of annealing and solid solution aging.The effects of different processes and microstructures on the strength and ductility of TC29 titanium alloy were studied.The results show that the alloy undergoes deformation in the two-phase zone,and after annealing or solid solution aging treatment,the microstructure presents a typical duplex microstructure.After deformation in the two-phase zone and solid solution at 850℃and aging treatment,the micrometer level secondaryαphase in the matrix disappears,and a large amount of nanometer level secondaryαphase precipitates.After single-phase deformation and solid solution aging treatment,the microstructure mainly consists of layeredαphase,and a large amount of nanoscale secondaryαphase precipitates in the matrix.The deformation specimen of the two-phase zone treated by solid solution aging has a higher tensile strength at room temperature with the increases of solid solution temperature,reaching a maximum of 1471 MPa.The impact toughness of the deformed sample in the two-phase zone after annealing can reach up to 58.8 J/cm^(2).The fracture toughness of the single-phase deformation specimen treated with solid solution aging is the highest,reaching 73 MPa·m~(1/2).The sample after deformation in the two-phase zone presents cleavage fracture,with brittle transgranular fracture as the main mode of fracture and a small number of pores visble.After deformation in the single-phase zone,the sample presents a mixture of cleavage and ductile dimples,with a large number of tearing edges,pores,and secondary cracks.

关 键 词：TC29钛合金 微观组织 强度 冲击韧 断裂韧性 

分 类 号：TG146.23[一般工业技术—材料科学与工程]