Fe-Mn-Si-Cr-Ni合金焊接接头组织和形状记忆效应研究  

Study on microstructure and shape memory effect in weld joints of an Fe-Mn-Si-Cr-Ni alloy

作　　者：乔志霞[1] 李宗民 刘永长[3] 王东爱[1] 欧凤萍[1] 

机构地区：[1]天津商业大学机械工程学院,天津300134 [2]河北省青龙县交通局,河北青龙066500 [3]天津大学材料学院,天津300072

出　　处：《功能材料》2007年第10期1645-1647,共3页Journal of Functional Materials

基　　金：国家自然科学基金资助项目(50401003);天津商学院青年科研培育基金资助项目(040111)

摘　　要：利用扫描电镜、X射线衍射仪对Fe-Mn-Si-Cr-Ni形状记忆合金钨极氩弧焊(TIG焊)接头组织进行分析,并利于弯曲变形法考察了焊接接头的形状记忆效应。结果表明,焊缝区由于重熔形成了树枝晶组织,该树枝晶组织又具有胞状亚结构。焊缝区相组成与母材一样仍然是单相奥氏体(γ),变形后能发生应力诱发γ→ε马氏体相变,该相变加热后完全可逆。热影响区组织除晶粒长大外无其它改变。Fe-Mn-Si-Cr-Ni合金经焊接后仍然保持良好的形状记忆效应。Microstructure of the weld joints in a tungsten-insert gas （TIG） welded Fe-Mn-Si-Cr-Ni shape memory alloy was investigated by using scanning electron microscope and X-ray diffraction, and shape memory effect of the weld joints was examined by bending tests. The results show that the weld zone consists of dendrite struc- tures with cellular sub-grains due to re-solidification after welding, but it is still composed of single phase of anstenite（7）, the same as base materials. Thus stress induced γ→ε martensite transformation occurred in the weld after deformation,which was completely able to reverse on heating. Microstructure in the heat-affected zone changed little after welding, except for the grown larger grain size. The Fe-Mn-Si-Cr-Ni shape memory alloy still exhibits excellent shape memory effect after TIG welding.

关 键 词：FE-MN-SI-CR-NI形状记忆合金 焊接接头 应力诱发γ→ε马氏体相变 形状记忆效应 

分 类 号：TG139.6[一般工业技术—材料科学与工程]