AZ31镁合金挤压棒材变路径压缩的微观机理  

Micro-mechanism of Various Paths Compression of the Extruded AZ31 Mg Alloy Rod

作　　者：宋广胜 张健强 牛嘉维 张士宏[3] Song Guangsheng;Zhang Jianqiang;Niu Jiawei;Zhang Shihong(Shenyang Aerospace University,Shenyang 110036,China;Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,China)

机构地区：[1]沈阳航空航天大学材料科学与工程学院,辽宁沈阳110036 [2]沈阳航空航天大学,辽宁沈阳110036 [3]中国科学院金属研究所,辽宁沈阳110016

出　　处：《稀有金属材料与工程》2019年第11期3563-3570,共8页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(51174189)

摘　　要：室温下,对AZ31镁合金挤压棒材分别进行2种变路径压缩变形,第1种为压缩方向为正交径向的两道次压缩,称为RD1-RD2压缩变形;第2种为压缩方向依次为挤压方向和径向的两道次压缩变形,称为ED-RD1压缩变形,并对上述压缩过程中晶粒取向和力学性能的变化特征进行了分析。结果表明,压缩变形过程中大量{1012}拉伸孪晶和{1012}-{1012}二次孪晶启动,不同的孪晶变体启动使晶粒中存在较多的交叉孪晶界,孪晶启动总体上遵循施密特定律。对于RD1-RD2压缩变形,两道应力应变曲线几乎相同,而对于ED-RD1压缩变形,第2道次压缩的应力应变曲线对应的应力值明显高于第1道次。An experimental investigation was carried out to measure two types of various compression paths on the extruded AZ31 Mg alloy rod at room temperature.The first type is a two-stepped compression with vertical radial directions,which was named as RD1-RD2 compression.The second type is that the compression direction is extruding direction and subsequent radial direction,which was named as ED-RD1 compression.The variation on grains orientation and mechanical properties during above compressions were analyzed.The results reveal that large amounts of{1012}extension twins and{1012}-{1012}secondary twins activate during deformation.Besides,many crossed twin boundaries form within grains caused by different twin variants activations.On the whole,twin activation obeys the Schmid law.On the one hand,for the RD1-RD2 compression,the stress-strain curves of the first and second compressions are almost identical.On the other hand,for the ED-RD1 compression,the stress values of the stress-strain curve of the second compression are significantly higher than that of the first compression.

关 键 词：AZ31镁合金 变路径压缩 孪晶 Schmid因子 

分 类 号：TG146.22[一般工业技术—材料科学与工程]