摘要
在Thermecmastor-Z动态热模拟试验机上对Ti-43Al-4Nb-1.4W合金进行高温压缩变形实验,实验温度范围为1 050~1 150℃,应变速率范围为0.001~1 s 1。根据该合金的真应力-真应变曲线,建立合金高温变形的本构方程和热加工图,并对不同变形区域的组织进行分析。结果表明：Ti-43Al-4Nb-1.4W合金高温压缩变形峰值应力与变形条件的关系可用双曲正弦函数来表示,其变形激活能为567.05 kJ/mol,高温变形的本构方程为：ε=3.37×1018.[sinh（0.0043σ）]3.27exp[567.05/（RT）];加工图显示该合金最佳加工区域的应变速率为0.001~0.01 s 1（η范围在40%~55%）,在此加工区域内合金发生较明显的动态再结晶和β相的球化。
The hot compressive deformation behaviour of Ti-43Al-4Nb-1.4W alloy was investigated in the temperature range of 1 050～1 150 ℃ at the strain rate range of 0.001～1 s 1 on Thermecmastor-Z hot simulator.The high temperature deformation constitutive equation and processing map were established through the true stress — true strain curves.Furthermore,the microstructure characteristics were studied.The results show that,the hyperbolic sine-type function is suitable for describing the relationship between the flow stress and the deformation conditions for the Ti-43Al-4Nb-1.4W alloy.The activation energies for hot deformation of the alloy is 567.05 kJ/mol,and the high temperature deformation constitutive equation of Ti-43Al-4Nb-1.4W alloy is ε =3.37×1018[sinh（0.0043σ）]3.27exp[ 567.05/（RT）];the processing map shows that the feasible deformation field is at the strain rate of 0.001～0.01 s 1（η=40%～55%）.Dynamic recrystallization and globalization of β phase occur in this deformation field.
出处
《粉末冶金材料科学与工程》
EI
北大核心
2013年第3期357-362,共6页
Materials Science and Engineering of Powder Metallurgy
基金
国家重点基础研究发展计划("973"计划)(2011CB605505)
陕西省重点基金项目(2011JZ007)
关键词
TIAL基合金
热变形行为
本构方程
热加工图
TiAl alloy
hot deformation behavior
constitutive equation
processing map
