摘要
利用双辊轧机对具有不同初始组织的TiZr基合金Ti-20Zr-6.5Al-4V(T20Z)进行多道次轧制变形,轧制温度为800~950℃,总变形量为62.5%,之后进行退火处理,采用光学显微镜、X射线衍射仪及万能力学性能试验机等研究了初始组织、轧制温度和退火温度对Ti-20Zr-6.5Al-4V合金等轴组织形成及力学性能的影响。结果表明:马氏体组织有利于均匀、细小等轴组织的形成,而高温退火后由于片层组织粗大,仅有部分组织发生等轴化。当轧制温度超过900℃时,不论是马氏体组织还是片层组织均发生β转变,均不能得到等轴组织。退火温度应控制在830℃左右,超过850℃后最终的退火组织为片层组织。经过淬火并轧制退火获得的细小等轴组织的屈服强度为1150 MPa,抗拉强度为1203 MPa,伸长率为13.16%,与原始粗大片层组织相比,抗拉强度和伸长率分别提高了30.5%和48.7%。
Multi-pass rolling deformation of TiZr based alloy Ti-20Zr-6.5Al-4V(T20Z)with different primary microstructure was carried out by double rolling mill,the rolling temperature was 800-950℃and the total deformation was 62.5%,and then it was annealed.Effects of primary microstructure,rolling temperature and annealing temperature on equiaxed microstructure formation and mechanical properties of the Ti-20Zr-6.5Al-4V alloy were studied by means of optical microscope,X-ray diffractometer and universal mechanical testing machine.The results show that the martensite structure is conducive to the formation of uniform and fine equiaxed microstructure,and only part of the microstructure is equiaxed due to the coarse lamellar microstructure after high temperature annealing.When the rolling temperature exceeds 900℃,both martensite and lamellar microstructure occurβtransformation,and no equiaxed microstructure can be obtained.The annealing temperature should be controlled at about 830℃,and the final annealing microstructure is lamellar microstructure after exceeding 850℃.The yield strength,tensile strength and elongation of the fine equiaxed structure obtained by quenching and rolling plus annealing are 1150 MPa,1203 MPa and 13.16%,respectively.Compared with the original coarse lamellar microstructure,the tensile strength and elongation are increased by 30.5%and 48.7%,respectively.
作者
岳赟
杜志浩
杜三明
熊毅
马明臻
YUE Yun;DU Zhi-hao;DU San-ming;XIONG Yi;MA Ming-zhen(National United Engineering Laboratory for Advanced Bearing Tribology,Henan University of Science and Technology,Luoyang 471023,China;State Key Laboratory of Metastable Materials Science and Technology,Yanshan University,Qinhuangdao 066004,China)
出处
《材料热处理学报》
CAS
CSCD
北大核心
2022年第2期58-65,共8页
Transactions of Materials and Heat Treatment
基金
国家自然科学基金(51801054)。
关键词
钛锆基合金
轧制
微观组织
力学性能
TiZr-based alloy
rolling
microstructure
mechanical property
