Al-Cu-Mg-Mn-Sc-Zr铝合金的流变行为与热加工图

Hot deformation behavior and processing map of Al-Cu-Mg-Mn-Sc-Zr aluminium alloy

Al-Cu-Mg-Mn-Sc-Zr铝合金的热变形行为是制定变形加工工艺的基础。采用Gleeble-3500模拟试验机对经均匀化处理的Al-Cu-Mg-Mn-Sc-Zr铝合金进行等温压缩模拟试验,试验温度为633~753 K,应变速率0.01~10s^(-1),测定真应力-真应变曲线,计算变形激活能,并建立加工图。结果表明:随变形温度升高或应变速率降低,合金的流变应力降低,热变形软化机制由动态回复逐渐转变为动态再结晶,第二相对位错滑移及晶界迁移起钉扎作用,阻碍再结晶进程。合金变形激活能为153.5 kJ/mol。633~663 K、0.01~0.07 s^(-1)以及693~723 K、0.01~0.1 s^(-1)两个区域为最佳变形区域。

The hot deformation behavior of Al-Cu-Mg-Mn-Sc-Zr aluminium alloy is a basis for formulating deformation processing technology.The isothermal compression simulation experiment was carried out on the homogenized Al-Cu-Mg-Mn-Sc-Zr aluminium alloy by Gleeble-3500 system under temperature of 633-753 K and strain rate of 0.01-10 s^(-1),the true strain-true stress curves were obtained,and deformation activation energy was calculated,and processing map was built-up.The results show that flow stress decreases and the softening mechanism changes from dynamic recovery to dynamic recrystallization with the increase of deformation temperature or the decrease of strain rate.The precipitates in the deformed alloy pin dislocation slip and grain boundary migration,and hinder recrystallization.The activation energy is 153.5 kJ/mol.633-663 K,0.01-0.07 s^(-1) and 693-723 K,0.01-0.1 s^(-1) are the best deformation regions.