挤压镁合金AZ31的压缩过程中的组织及织构演化  

Microstructure and texture evolution during compression of magnesium alloy AZ31

作　　者：尹树明[1] 赵述哲[1] 成泰民[1] 

机构地区：[1]沈阳化工大学,辽宁沈阳110142

出　　处：《轻金属》2012年第6期54-57,共4页Light Metals

基　　金：国家自然科学基金(批准号:10647138);辽宁省教育厅科学研究项目(批准号:20060667)资助课题

摘　　要：对常规挤压态镁合金AZ31压缩过程的组织及织构演化进行了扫描电镜-电子背散射衍射(SEM-EBSD)原位观察。结果表明材料的初始组织为等轴晶,晶粒的平均尺寸为76微米,晶粒内部未发现形变孪晶。材料的初始织构类型为典型的{11-20}丝织构,即大多数晶粒的<11-20>晶向平行于棒材的挤压方向(ED)。在压缩过程中,多数晶粒内部开始出现拉伸孪晶,随着压缩应变的增加,孪晶片层不断增厚,导致晶内的孪晶合并成大的孪晶并占据晶粒内部的大部分区域进而使孪晶的体积分数不断增加。随着压缩压缩应变的增加初始丝织构不断减弱并有新的基面织构形成。实验表明压缩过程中的{10-12}<10-11>孪生而非滑移是引起压缩过程中织构演化的主要原因。The microstructure and texture evolution of conventional extruded AZ31 magnesium alloy during compression were in situ observed by means of electron backscatter diffraction（EBSD） technique. The results showed that the grains of as- extruded specimen were cquiaxed with an average size of 76 μm, and no twins could be found in the grains. The initial texture was typical 〈 11 - 20 〉 fiber texture,in which most of grains with theirs 〈 11 - 20 〉 paralleled to the extruded direction （ED）. During compression, tension twinning occured in most grains. The volume fraction of the twins increaseed as com- pressive strain increased due to the twins grewed fater and fater then merged into large ones which result in the grain almost occupied by the twins. It also noted that the initial texture weekeued gradully and new basal texture gradully formed with compressive strain increasing. The present results indicated that tenssion twinning rather than slip is the main cause of texture change during compression.

关 键 词：织构 电子被反射衍射(EBSD) 孪生 

分 类 号：TG146.22[一般工业技术—材料科学与工程]