2519A铝合金热压缩流变行为和显微组织分析

在Gleeble-1500D热模拟仪上进行热压缩实验，研究温度从300℃～450℃、应变速率为0．001～10s^-1时2519A铝合金热压塑行为，并用金相显微镜分析在不同热压缩条件下的组织形貌特征。结果表明，流变应力开始随着应变的增大而增大，出现峰值之后慢慢减小并慢慢趋于平稳。应力峰值随温度的增加而减小，随应变增大而增大，其热变形行为可用包含Zener-Hollomon参数的双弦本构关系来描述，得到平均激活能Q=223．11706kj／mol。合金在0．001s^-1～1s^-1。应变速率条件下软化机制主要为动态回复，而当应变速率上升到10s^-1后，合金微观组织出现局部动态再结晶。

Flow Behavior and Microstructure Analysis of 2519A Aluminnum Alloy During Hot Compression Deformation

The high temperature deformation behavior of 2519A Aluminnum alloy at 300℃ - 450℃ and strain rate of 0. 001 s-1- 10 s-1 was studied by Gleeble--1500 hot simulator. The microstructure of different deformation conditions was observed by optical microscopy. The results show that the flow stress exhibits a peak stress at critical strain, the flow stress decreases monotonically with the increase of strain, and then tends to be constant until high strain. The peak stress decreases with the increase of deformation temperature and the decrease of strain rate. which can be represented by a Zener--Hollomon parameter in the hyperbolic sine equation, it＇s hot deformation activation energy is 223. 11706 kJ/mol. The alloy shows dy- namic recovery during the strain rate of 0. 001s-1-1s-1 , and shows partial dynamic recrystallization as the strain rate increase to 10s-1.