Deformation behavior and microstructural evolution of Al-Zn-Cu-Mg-Sc-Zr alloy during high temperature compression  

作　　者：李文斌 潘清林 刘俊生 梁文杰 何运斌 刘晓艳 

机构地区：[1]School of Materials Science and Engineering, Central South University [2]Department of Civil Engineering, Hunan City University

出　　处：《Journal of Central South University》2009年第4期530-534,共5页中南大学学报（英文版）

基　　金：Project(2006AA03Z523) supported by the National High-Tech Research and Development Program of China

摘　　要：The deformation behavior of a new Al-Zn-Cu-Mg-Sc-Zr alloy was investigated with compression tests in temperature range of 380?470 ℃ and strain rate range of 0.001-10 s-1 using Gleeble 1500 system, and the associated microstructural evolutions were studied by metallographic microscopy and transmission electron microscopy. The results show that true stress—strain curves exhibit a peak stress, followed by a dynamic flow softening at low strains (ε<0.05). The stress decreases with increasing deformation temperature and decreasing strain rate, which can be represented by a Zener-Hollomon exponential equation with the activation energy for deformation of 157.9 kJ/mol. The substructure in the deformed specimens consists of few fine precipitates with equaixed polygonized subgrains in the elongated grains and developed serrations at the grain boundaries. The dynamic flow softening is attributed mainly to dynamic recovery and dynamic recrystallization.The deformation behavior of a new Al-Zn-Cu-Mg-Sc-Zr alloy was investigated with compression tests in temperature range of 380-470 ℃ and strain rate range of 0.001-10 s^-1 using Gleeble 1500 system, and the associated microstructural evolutions were studied by metallographic microscopy and transmission electron microscopy. The results show that true stress-strain curves exhibit a peak stress, followed by a dynamic flow softening at low strains （ε〈0.05）. The stress decreases with increasing deformation temperature and decreasing strain rate, which can be represented by a Zener-Hollomon exponential equation with the activation energy for deformation of 157.9 kJ/mol. The substructure in the deformed specimens consists of few fine precipitates with equaixed polygonized subgrains in the elongated grains and developed serrations at the grain boundaries. The dynamic flow softening is attributed mainly to dynamic recovery and dynamic recrystallization.

关 键 词：Al-Zn-Cu-Mg-Sc-Zr alloy hot deformation flow softening microstructural evolution activation energy 

分 类 号：TG131[一般工业技术—材料科学与工程]