Ti60钛合金超塑变形行为及本构模型  

Superplastic deformation behavior and constitutive model on Ti60 titanium alloy

作　　者：廖子颖 李保永[1] 刘伟 秦中环 吴迪鹏 武永 Liao Ziying;Li Baoyong;Liu Wei;Qin Zhonghuan;Wu Dipeng;Wu Yong(Beijing Hangxing Machine Manufacturing Co.,Ltd.,Beijing 100013,China;College of Mechanical and Electrical Engineering,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,China)

机构地区：[1]北京航星机器制造有限公司,北京100013 [2]南京航空航天大学机电学院,江苏南京210016

出　　处：《锻压技术》2024年第8期249-254,共6页Forging & Stamping Technology

基　　金：国家重点研发计划资助项目(2023YFB3407000);国防基础科研计划(JCKY2021204A004)。

摘　　要：为确定Ti60钛合金的超塑变形行为,促进Ti60钛合金工程化应用,进行了Ti60钛合金在变形温度为880~960℃和应变速率为0.0001~0.01 s^(-1)条件下的超塑拉伸试验。结果表明:Ti60钛合金在960℃、0.001 s^(-1)条件下的伸长率达到最大值,为365%;在较低应变速率(0.001和0.0001 s^(-1))条件下,材料呈现明显的应变硬化,在较低变形温度(880℃)、较高应变速率(0.01 s^(-1))条件下,材料出现应力软化;当变形温度一定时,随着应变速率的降低,峰值应力降低。基于Arrhenius方程构建了本构模型,并提出不区分流动应力水平直接求解Arrhenius方程的方法,引入应变变化修正Arrhenius方程。修正Arrhenius方程的理论计算值与试验值的相关系数R为0.9914,平均相对误差为6.62%,计算结果与试验结果误差在可接受范围内,为采用Ti60钛合金进行复杂构件超塑成形提供数据支撑。To determine the superplastic deformation behavior of Ti60 titanium alloy and promote its engineering application,superplastic tensile tests were conducted on Ti60 titanium alloy at the deformation temperatures of 880-960℃and the strain rates of 0.0001-0.01 s^(-1).The results show that the elongation of Ti60 titanium alloy reaches its maximum value in the condition of 960℃and 0.001 s^(-1),which is 365%.At lower strain rates(0.001 and 0.0001 s^(-1)),the material exhibits significant strain hardening,while at lower deformation temperature(880℃)and higher strain rate(0.01 s^(-1)),the material exhibits stress softening.When the deformation temperature is constant,the peak stress decreases with the decreasing of strain rate.Based on the Arrhenius equation,a constitutive model is constructed,and a method for directly solving the Arrhenius equation without distinguishing the flow stress level is proposed.The strain change is introduced to modify the Arrhenius equation.The correlation coefficient R between the theoretical calculation value of the modified Arrhenius equation and the test value is 0.9914,with an average relative error of 6.62%.The error between the calculated and test results is within an acceptable range,which provides the data support for the use of Ti60 titanium alloy in complex component superplastic forming.

关 键 词：Ti60钛合金 高温钛合金 超塑性 本构模型 Arrenhius方程 

分 类 号：TG131[一般工业技术—材料科学与工程]