Mg-Gd-Y-Zn合金中长周期堆垛结构形成的原位准动态背散射电子显微研究  

Formation of long period stacking structures in Mg-Gd-Y-Zn alloy studied by in-situ quasi-dynamic back-scattering electron microscopy

作　　者：刘林林[1] 孙威[1] 王飞[1] 张泽[1] 

机构地区：[1]北京工业大学固体微结构与性能研究所,北京100124

出　　处：《电子显微学报》2008年第4期266-270,共5页Journal of Chinese Electron Microscopy Society

基　　金：国家自然科学基金资助项目(No.50571002)~~

摘　　要：本文利用原位准动态背散射电子显微像(BSE)并结合透射电镜观察研究了MgGd1.8Y0.8Znx(at.%)(x=0.12,0.8,1.3)合金中长周期堆垛结构(LPS)的形成及生长形态。结果表明,当Zn含量较少时(x=0.12),铸态和各种热处理状态的合金中都未形成LPS。而在Zn含量相对较多的铸态合金(x=0.8,1.3)中,发现6层周期LPS的形成,而且Zn含量越多,LPS的体积分数越大。在300℃进行热处理时,LPS可以沿Mg基体{0001}面生长,原位准动态BSE观察可以直接揭示与LPS的生长相关的形貌变化。The formation and growth morphology of long period stacking （LPS） structures in MgGd1.8 Y0.8 Znx （at. % ） （x = 0.12, 0. 8, 1.3） alloys have been investigated by combination of in-situ quasi-dynamic back-scattering electron microscopy （BSE） and transmission electron microscopy. The results show that no LPS can be formed in as-cast and heat treated MgGd1.8 Y0.8 Znx alloys when Zn-content is low （ x = 0. 12）. In contrast, a kind of 6-layered LPS has been found to form in as-cast MgGd1.8 Y0.8 Znx alloys with high Zn-content （x = 0.8, 1.3）. The fraction of volume for the LPS formed is in proportion to Zn-content. When heat treated at 300℃, the LPS in as-cast state can grow along （0001） Mg planes, whose morphology variations can be revealed directly by in-situ quasi-dynamic BSE observations.

关 键 词：准动态观察 Mg-Gd-Y-Zn合金 长周期堆垛结构 背散射电子像 

分 类 号：TG146.22[一般工业技术—材料科学与工程]