摘要
在DIL805A/T热模拟机上对TC4进行了等温压缩试验,研究了该合金在变形量为55%温度为870、920、970、1020℃、应变速率为0.001~1 s^(-1)的条件下的高温变形行为。使用双曲正弦形式修正的Arrhenius关系来描述TC4钛合金高温压缩变形时最大变形抗力的本构方程。绘制出TC4钛合金的加工图,通过使用金相显微镜观察微观组织验证加工图的有效性。结果表明,应力-应变图可以很好地反映TC4钛合金在不同变形条件下的应力状态,且应力值和试验值有较好相关性(R^2=0.9006),通过观察微观组织得出在920℃、0.01 s^(-1)的应变条件下试样组织为典型的(α+β)组织,组织稳定,韧性好,高温强度高,材料加工综合性能最好。结合热加工与组织分析,TC4钛合金的最佳工艺参数是在900~950℃,0.01~0.1 s^(-1)的应变条件下。
High temperature isothermal compression experiment of TC4 titanium alloy at temperature ranging from 870 to 1020℃ and stain rates from 0.001 s -1 to 1 s -1 was investigated by high temperature deformation behavior tests on DIL805A/T thermo-mechanical simulator. The modified Arrhenius model was used to describe the TC4 high temperature compression deformation. Based on dynamic material model map the TC4 titanium alloy processing figure uas obtained, whose efectiveness uas verified by using metallographic microscope observation of microstructure demonstrated the effectiveness of processing figure. The results show that stress-strain diagrams can well reflect the stress of TC4 titanium alloy under different deformation conditions and the stress value and experimental value have a good correlation ( R2 = O. 9006). Microstructure of the specimen under the deformation condition of 920℃ with 0.01 s-1 strainrate typically (α+β)phase, which is stable and has, good toughness, high temperature strength and the best comprehensive processing performance. It is concluded that the TC4 titanium alloy has the best processing performance under the deformation condition of 900-950℃ with 0.01-0.1 s-1 strain rate.
出处
《金属热处理》
CAS
CSCD
北大核心
2017年第5期121-126,共6页
Heat Treatment of Metals
基金
贵州省科技厅重大专项子课题(黔科合重大专项字[2014]6013号)
关键词
TCA钛合金
高温压缩
本构方程
加工图
TC4 titanium alloy
high temperature compression
constitutive equations
processing figure
作者简介
白娇娇(1991-),女,硕士研究生,研究方向:钛合金的高温压缩变形行为,E-mail:m18798011462@163.com。
通讯作者:李伟,博士,副教授,E-mail:liweiem@163.com