Al-Mn-Mg-Cu-Ni合金热压缩变形的流变行为和组织

Flow behavior and microstructure of Al-Mn-Mg-Cu-Ni alloy during hot compression deformation

在Gleeble-1500热模拟机上对Al-Mn-Mg-Cu-Ni合金进行热压缩试验,分析合金的流变应力与应变速率和变形温度之间的关系,计算高温变形时的变形激活能,并研究合金在变形过程中的显微组织。结果表明:Al-Mn-Mg-Cu-Ni合金在本实验条件下具有正的应变速率敏感性;流变应力随应变速率的增大而增大,随变形温度的升高而减小。该合金热压缩变形的流变应力行为可用双曲正弦形式的本构方程来描述,也可用Zener-Hollomon参数来描述,其变形激活能为209.84kJ/mol。随着热变形温度的升高和应变速率的减小,合金中的主要软化机制逐步由动态回复转变为动态再结晶。

The hot compression deformation test of Al-Mn-Mg-Cu-Ni alloy was performed on Gleeble-1500 system.The relationships between flow stress and deformation temperature as well as strain rate were analyzed,and the deformation activation energy was calculated.The microstructures during the hot deformation process were observed.The results show that the flow stress is sensitive to the strain rate and the deforming temperature.The flow stress increases with increasing the strain rate,and decreases with increasing the deforming temperature,which can be described by a constitutive equation in hyperbolic sine function with the hot deformation activation energy of 209.84 kJ/mol,and can also be described by a Zener-Hollomon parameter.The main soften mechanism of the alloy transforms from dynamic recovery to dynamic recrystallization with increasing the temperature and decreasing the strain rate.