摘要
在 Gleeble2 0 0 0热模拟机上对一种 2 0 19Al- L i合金进行高温扭转试验 ,研究了合金扭转时的等效应力 -应变关系和扭转变形组织特征。研究结果表明 :合金表现出与压缩变形类似的稳态流变特征 ,扭转等效应力随变形温度的升高和应变速率的降低而减小 ;其变形过程属于受位错速率机制控制的热激活过程 ,等效应力、等效应变速率和温度之间基本上满足双曲正弦函数关系 ;扭转时的高温变形组织随初始 ln Z值的变化而发生变化 ,当温度达到一定值和 ln Z低于一定值时 ,合金变形时可发生动态再结晶 ,再结晶程度随ln
High temperature torsional testing of the alloy 2091 Al Li was carried out on Gleeble 2000 machine to study equivalent stress strain relationship and microstructural characterazation The results show that the alloy exhibits a steady state deformation similar to compression. The equivalent stress decreases with the increase of deformation temperature and the decrease of strain rate. The deformation of the alloy is confirmed to be a thermal activated porcess which is governed by rate controlling process of dislocation, and the correlations of equivalent stress to the strain rate and temperature are obeyed by a hypobolic sine rule. The as deformed microstructure of the alloy varies with initial lnZ value. Dynamic recrystallization can be activated when temperature exceeds a critical temperature and lnZ value is lower than a critical value, and the extent of dynamic recrystallization increases with the decrease of lnZ.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2000年第2期114-117,共4页
Rare Metal Materials and Engineering
