Microstructural changes during the martensitic transformation from face centred cubic (FCC) to body centred cubic (BCC) in an Fe-31Ni alloy were observed by scanning electron microscopy (SEM) with a newly developed Peltier stage available at temperatures to -75 °C. Electron channelling contrast imaging (ECCI) was utilized for the in situ observation during cooling. Electron backscatter diffraction (EBSD) analysis at ambient temperature (20 °C) after the transformation was performed for the crystallographic characterization. A uniform dislocation slip in the FCC matrix associated with the transformation was detected at -57 °C. Gradual growth of a BCC martensite was recognized upon cooling from -57 °C to -63 °C.

中文翻译：

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新型 -75 °C SEM 冷却台：用于钢中的马氏体转变

通过扫描电子显微镜 (SEM) 观察了 Fe-31Ni 合金中从面心立方 (FCC) 到体心立方 (BCC) 的马氏体转变过程中的微观结构变化，使用新开发的珀尔帖阶段可在 -75 °C 的温度下使用。电子通道对比成像 (ECCI) 用于冷却过程中的原位观察。转化后在环境温度 (20 °C) 下进行电子背散射衍射 (EBSD) 分析以进行晶体学表征。在 -57 °C 下检测到与转变相关的 FCC 基质中的均匀位错滑移。BCC 马氏体在从 -57 °C 冷却到 -63 °C 时逐渐生长。