新型TA32钛合金板的高温拉伸变形行为
2019年1月第43卷第1期 Vol.43No.1Jan.2019
DOI :10.11973/j x g ccl201901015
收稿日期:2017-11-07;修订日期:2018-12-11作者简介:龚宗辉(1993－)
,男,河南商丘人,硕士研究生通信作者(导师):谢兰生教授新型TA32钛合金板的高温拉伸变形行为
龚宗辉,谢兰生,陈明和,叶建华
(南京航空航天大学机电学院,南京210016)
摘 要:在变形温度650 850?二应变速率0.001 0.100s －1条件下对TA32钛合金板进行高温拉伸试验,研究了变形温度和应变速率对合金高温拉伸变形行为的影响;基于修正的Hooke 定律和Grosman 方程建立TA32钛合金的高温流变本构方程并进行试验验证三结果表明:TA32钛合金的流变应力受变形温度和应变速率的影响显著,变形温度的升高和应变速率的降低均会使流变应力减小;在变形温度650?二应变速率0.100s －1下,
合金的抗拉强度为680MPa ,约为常温抗拉强度的80％,合金仍具有较高的强度;当变形温度由750?升至850?时,合金伸长率的增长幅度和强度的下降幅度均较明显,合金塑性较好;采用建立的高温流变本构方程计算得到的真应力-
真应变曲线与试验结果基本吻合,其相关系数和平均相对误差分别为0.9794和11.1％,
该本构模型可较好地描述TA32钛合金的高温拉伸变形行为三
关键词:TA32钛合金;
高温拉伸;流变应力;本构方程中图分类号:TG146.2 文献标志码:A 文章编号:1000-3738(2019)01-0069-06Hi g h T em p erature T ensile Deformation Behavior of New Titanium Allo y Sheet T A32GONG Zon g hui ,XIE Lanshen g ,CHEN Min g he ,YE Jianhua (Colle g e of Mechanical and Electrical En g ineerin g ,Nan j in g Universit y of Aeronautics and Astronautics ,Nan j in g 210016,China )
Abstract :Hi g h tem p erature tensile tests at deformation tem p eratures of 650－850?and strain rates of 0.001－0.100s －1were conducted on TA32titanium allo y sheet.The influence of deformation tem p erature and strain rate on hi g h tem p erature tensile deformation behavior of the allo y was investi g ated.The hi g h tem p erature rheolo g ical constitutive model of TA32titanium allo y was established on the basis of modified Hooke law and Grosman e q uation ,and verified b y tests.The results show that the flow stress of TA32titanium allo y was si g nificantl y affected b y the deformation tem p erature and strain rate.The flow stress decreased with the increase of deformation tem p erature and the decrease of strain rate.The tensile stren g th of the allo y reached 680MPa at the deformation tem p erature of 650?and strain rates of 0.100s －1,which was about 80％of the tensile stren g th at room tem p erature ;the allo y still had the relativel y hi g h stren g th.When the deformation tem p erature increased from 750?to 850?,the elon g ation increased and the stren g th decreased obviousl y ,indicatin g the allo y had relativel y g ood p lasticit y .The true stress -true strain curves calculated b y the established hi g h tem p erature rheolo g ical constitutive e q uation were in a g reement with the tested results ,and the correlation coefficient and avera g e relative error were 0.9794and 11.1％,res p ectivel y ,indicatin g that the constitutive model could describe the hi g h tem p erature tensile deformation behavior of TA32titanium allo y .Ke y words :TA32titanium allo y ;hi g h tem p erature tension ;flow stress ;constitutive e q uation
0 引 言TA32钛合金是在TA12钛合金的基础上研制的一种新型近α型高温钛合金,其塑性和抗蠕变性
能优良,在航空发动机加力燃烧室筒体和巡航导弹
弹体中均有应用,是一种很有应用潜力的耐高温钛
合金[1-3]三TA32钛合金在常温下的塑性较差,一般
采用热成形工艺对其进行加工[4],因此开展TA32钛合金高温流变行为的研究对其成形工艺方案的制96万方数据