Microstructural evolution of Mg-7Al-2Sn Mg alloy during multi-directional impact forging  

作　　者：M.G.Jiang H.Yan L.Gao R.S.Chen 

机构地区：[1]The Group of Magnesium Alloys and Their Applications,Institute of Metal Research,Chinese Academy of Sciences,62 Wencui Road,Shenyang 110016,China [2]University of Chinese Academy of Sciences,19 Yuquan Road,Beijing 100049,China [3]General Motors China Science Lab,56 Jinwan Road,Pudong,Shanghai 201206,China

出　　处：《Journal of Magnesium and Alloys》2015年第3期180-187,共8页镁合金学报（英文）

基　　金：The authors gratefully acknowledge the financial support from General Motors Corporation,the National Basic Research Program of China(973 Program,No.2013CB632202);National Natural Science Foundation of China(NSFC,No.51301173).

摘　　要：Multi-directional impact forging(MDIF)was applied to a Mg-7Al-2Sn(wt.%)Mg alloy to investigate its effect on the microstructural evolution.MDIF process exhibited high grain refinement efficiency.After MDIF 200 passes,the grain size drastically decreased to 20µm from the initial coarse grains of~500µm due to dynamic recrystallization(DRX).Meanwhile,original grain boundaries remained during MDIF and large numbers of fine sphericalβ-Mg_(17)Al_(12) particles dynamically precipitated along the original grain boundaries with high Al concentration,acting as effective pinning obstacles for the suppression of DRXed grain growth.Besides,micro-cracks nucleated during MDIF and propagated along the interface between the remained globular or cubic Al-Mn particles and Mg matrix.

关 键 词：Magnesium alloy FORGING Grain refinement Dynamic precipitation 

分 类 号：TG1[金属学及工艺—金属学]