Effects of retrogression heating rate on microstructures and mechanical properties of aluminum alloy 7050  

作　　者：李国锋 张新明 李鹏辉 游江海 

机构地区：[1]School of Materials Science and Engineering, Key Laboratory of Nonferrous Metal Material Science and Engineering of Ministry of Education, Central South University

出　　处：《Transactions of Nonferrous Metals Society of China》2010年第6期935-941,共7页中国有色金属学报（英文版）

基　　金：Project(2005CB623700) supported by the National Basic Research Program of China

摘　　要：The effects of the retrogression heating rate(340℃/min,57℃/min,4.3℃/min)on the microstructures and mechanical properties of aluminum alloy 7050 were investigated by means of hardness measurement,tensile properties testing,differential scanning calorimetry(DSC)and transmission electron microscopy(TEM).The results show that the retrogression heating rate significantly affects the microstructures and mechanical properties of the alloys treated by retrogression and re-aging(RRA)process, and it is found that the medium rate(57℃/min)leads to the highest mechanical properties.The strengthening phases in the matrix are mainly the fine dispersed η′precipitates and GP zones,and the grain boundary precipitates are coarse and discontinuous η phases.The effects of the retrogression heating rate（340℃/min,57℃/min,4.3℃/min）on the microstructures and mechanical properties of aluminum alloy 7050 were investigated by means of hardness measurement,tensile properties testing,differential scanning calorimetry（DSC）and transmission electron microscopy（TEM）.The results show that the retrogression heating rate significantly affects the microstructures and mechanical properties of the alloys treated by retrogression and re-aging（RRA）process, and it is found that the medium rate（57℃/min）leads to the highest mechanical properties.The strengthening phases in the matrix are mainly the fine dispersed η′precipitates and GP zones,and the grain boundary precipitates are coarse and discontinuous η phases.

关 键 词：aluminum alloy 7050 retrogression and re-aging treatment MICROSTRUCTURE mechanical properties 

分 类 号：TG146.21[一般工业技术—材料科学与工程] TQ530.2[金属学及工艺—金属材料]