TA5钛合金热变形行为及本构模型  

Hot deformation behavior and constitutive model of TA5 titanium alloy

作　　者：王俊[1] 王克鲁[1] 鲁世强[1] 李鑫[1] 欧阳德来[2] 邱仟 郭伟 WANG Jun;WANG Ke-lu;LU Shi-qiang;LI Xin;OUYANG De-lai;QIU Qian;GUO Wei(School of Aerospace Manufacturing Engineering,Nanchang Hangkong University,Nanchang 330063,China;School of Materials Science and Engineering,Nanchang Hangkong University,Nanchang 330063,China)

机构地区：[1]南昌航空大学航空制造工程学院,江西南昌330063 [2]南昌航空大学材料科学与工程学院,江西南昌330063

出　　处：《塑性工程学报》2022年第5期153-160,共8页Journal of Plasticity Engineering

基　　金：国家自然科学基金资助项目(51761029);南昌航空大学研究生创新专项基金资助项目(YC2020026)。

摘　　要：使用Gleeble-3800热模拟试验机对TA5钛合金进行等温恒应变速率压缩实验,研究其在实验条件为850~1050℃/0.001~10 s^(-1)和最大高度压下率为60%下的热变形行为。结果表明:当变形温度为850~950℃时,流变应力曲线呈动态软化特征;当变形温度为1000~1050℃时,流变应力曲线呈稳态特征。当变形条件为850℃/0.001 s^(-1)时,组织中出现部分动态再结晶,组织均匀性较差;在变形温度为900℃时,组织相对均匀,动态再结晶程度较高,并随着变形温度的升高,晶粒尺寸增大;当变形温度达1000℃以上时,组织中有针状α相析出,并随着变形温度的升高,针状α相长大。当变形温度为900℃时,应变速率的增加导致晶粒不断被拉长,应变速率为0.01~1 s^(-1)时,晶界呈不规则锯齿状。最后建立基于应变耦合的Z参数修正的Arrhenius本构模型,预测了TA5钛合金的流变行为,得到其相关系数R 2值为0.993,平均相对误差AARE为4.43%,说明所建立的本构模型具有较高的精确度。The hot deformation behavior of TA5 titanium alloy under the experimental conditions of 850-1050℃/0.001-10 s^(-1) and the maximum height reduction rate of 60%was studied using Gleeble-3800 thermal simulation test machine.The results show that the flow stress curves show dynamic softening characteristics at the deformation temperature of 850-950℃.At the deformation temperature of 1000-1050℃,the flow stress curves show steady characteristics.When the deformation condition is 850℃/0.001 s^(-1),partial dynamic recrystallization occurs in the microstructure and the uniformity of microstructure is poor.When the deformation temperature is 900℃,the microstructure is relatively uniform and the degree of dynamic recrystallization is high,and the grain size increases with the increase of deformation temperature.When the deformation temperature is above 1000℃,the needle-likeαphase is precipitated in the microstructure,and grow up with the increase of deformation temperature.When the deformation temperature is 900℃,the grain is elongated with the increase of strain rate.When the strain rate is 0.01-1 s^(-1),the grain boundary shows irregular zigzag shape.Finally,an Arrhenius constitutive model based on Z-parameter modification of strain coupling was established,and the rheological behavior of TA5 titanium alloy was predicted.The value of correlation coefficient R 2 is 0.993,and the average relative error AARE is 4.43%,which indicats that the established constitutive model has high accuracy.

关 键 词：TA5钛合金 热变形行为 动态再结晶 本构模型 

分 类 号：TG146.2[一般工业技术—材料科学与工程]