中文摘要：

采用电孤熔炼-真空甩带-长时间高温退火工艺制备了Ni50 Mn37 Sn13、Ni50 Mn37 Sn13 Co9和Ni50 Mn37 Sn13-Fe9三种不同状态下的Heusler合金.利用光学显微镜、X射线衍射仪、差示扫描量热仪及电子探针对所得铸锭、薄带及高温退火薄带试样进行显微组织结构分析.结果表明3种合金的铸锭试样均为枝晶结构,由马氏体、奥氏体及杂质相组成;薄带试样仅为单一奥氏体相;退火后的薄带试样又恢复到类似于铸锭试样的组织结构.另外,Co/Fe元素的加入增加了合金凝固时的成分过冷度,且没有改变合金的组织结构,只是分别占据了合金中的Mn/Ni原子位点.

英文摘要：

Ni50 Mn37 Sn13,Ni50 Mn37 Sn13 Co9 and Ni50 Mn37 Sn13 Fe9 Heusler alloys were prepared by arc meltingmelt spun-annealing with high temperature.The microstructure of ingots,ribbons and annealed ribbons were tested by optical microscope （OM）,X-ray diffractometer （XRD）,differential scanning calorimeter （DSC） and electron probe microanalyzer （EPMA）.The results show that the microstructure of the three ingots is dendritic crystal composited by martensite,austenite and some impurity phase; the ribbons consist of single austenite phase; the annealed ribbons have the similar structure with ingots.Besides,the composition super-cooling increases by addition of Co/Fe,and the structure of these three alloys has no change which suggests that Co/Fe just occupy the Mn/Ni sites respectively.