TC2钛合金的高温热变形行为  

Hot Deformation Behavior of TC2 Titanium Alloy

作　　者：李沐泽 柏春光[1,2] 张志强 赵建[1] 徐东生 王岩峰[3] LI Muze;BAI Chunguang;ZHANG Zhiqiang;ZHAO Jian;XU Dongsheng;WANG Yanfeng(Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,China;School of Materials Science and Engineering,University of Science and Technology of China,Shenyang110016,China;Chaoyang Jinda Titanium Co.,Ltd.,Chaoyang 122000,China)

机构地区：[1]中国科学院金属研究所,沈阳110016 [2]中国科学技术大学材料科学与工程学院,沈阳1100163 [3]朝阳金达钛业股份有限公司,朝阳122000

出　　处：《材料研究学报》2020年第12期892-904,共13页Chinese Journal of Materials Research

基　　金：国家重点研发计划(2017YFB0306201,2016YFB0701303)。

摘　　要：对TC2钛合金的高温变形行为进行了有限元模拟和热压缩实验研究,使用有限元自洽模型模拟提高流动应力曲线修正精度,分析材料的应力应变曲线特征,得到其高温流动本构方程和激活能,并进行了光学显微镜观察研究其微观组织演变规律,发现在高温低应变速率下α相的球化程度较高。绘制出TC2钛合金的功率耗散图和热加工图,结合应变速率敏感系数m研究了受m值控制的不同变形机制,最终确定了TC2钛合金的最佳加工窗口:(I)760~825℃、0.007~0.024 s^-1;(II)850~900℃、0.018~0.37 s^-1;(III)900~950℃、1~10 s^-1,在此区间功率耗散因子较大,在材料变形过程中发生充分动态再结晶,试样的微观组织呈细小等轴状。The high temperature deformation behavior of TC2 Ti-alloy was investigated by means of finite element simulations and isothermal hot compression tests parallelly.Firstly,the characteristic stressstrain curves of TC2 were analyzed,and the high temperature constitutive equation and activation energy were acquired.Secondly,the microstructure evolution was observed with optical microscope.It was found that the globularization ofα-phase is obvious at high temperature and low strain rate.Thirdly,the power dissipation and thermal processing map of TC2 Ti-alloy were drawn.And the deformation mechanism was characterized by strain rate sensitivity exponent m.Lastly,and the optimized processing window of TC2 Ti-alloy was determined as:(I)760~825℃,0.007~0.024 s-1;(II)850~900℃,0.018~0.37 s^-1;and(III)900~950℃,1~10 s^-1.Within these ranges the power dissipation rate of TC2 Ti-alloy is significant and sufficient dynamic recrystallization occurs in the process of deformation.

关 键 词：金属材料 TC2钛合金 热变形行为 热加工图 组织演变 

分 类 号：TG146[一般工业技术—材料科学与工程]