摘要
在Gleeble-3800型热加工模拟实验机上,对BTi-62421S合金在变形程度70%、变形温度850～1050℃、应变速率0.01～30 s^(-1)范围内进行高温压缩实验。通过真应力—真应变曲线,分析流动应力随变形热力参数的变化规律。结果表明:BTi-62421S合金高温变形的流变应力随温度的升高和应变速率的降低而减小;随着应变的增大,合金的真应力—真应变曲线在经历了明显的加工硬化阶段后达到最大值,然后出现流变"软化"现象。以经典的双曲正弦形式模型为基础建立了BTi-62421S合金高温变形的本构方程,同时通过对数据回归处理计算了合金高温变形的应力指数n、应变激活能Q。
The high temperature compression tests of BTi-62421S titanium alloy were carried out in the temperature range of 850-1 050 ℃ and strain rate range of 0.01-30 s^-1 using the Glceble3800 thermal-mechanical simulator. The change of flow stress with deformation thermal parameters was revealed from true stress---true strain curves. The results show that the true stress of high temperature deformation of BTi-62421S alloy increases with the decrease of deformation temperature and the increase of strain rate. With the increase of true strain, due to the work hardening of the alloy, the true stress attains the peak, and then flow softening occurs. The constitutive equation for high temperature deformation of BTi-62421S alloy is obtained on the basis of hyperbolic sine form model, and the material constants, including activation energy Q and stress exponent n are also obtained.
出处
《中国有色金属学报》
EI
CAS
CSCD
北大核心
2010年第B10期514-517,共4页
The Chinese Journal of Nonferrous Metals
基金
国家自然科学基金资助项目(50735005)
关键词
BTi-62421S
高温变形
流动应力
本构模型
BTi-62421S Ti alloy
high temperature deformation
flow stress
constitutive equation
