Abstract The microstructure evolution of a FeNiCr alloy oxidized at 600 °C by simultaneously applying stress via high temperature nanoindentation is reported. Analysis using transmission electron microscopy shows that a sharp crack was induced beneath the indentation area under the stress-oxidation coupling condition. Nanotwins beneath the indentation area were also observed, which acted as a barrier that ceased the crack propagation beneath the indenter by altering the path of the crack. Results reveal a transformation from inter-granular crack propagation along the oxide grain boundaries to intra-granular crack propagation through the nanotwin structure with a zig-zag pattern.

中文翻译：

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高温纳米压痕应力-氧化耦合诱导FeNiCr合金显微组织演变

摘要 报道了通过高温纳米压痕同时施加应力在 600 °C 下氧化的 FeNiCr 合金的微观结构演变。使用透射电子显微镜分析表明，在应力-氧化耦合条件下，压痕区域下方产生了尖锐的裂纹。还观察到压痕区域下方的纳米孪晶，它作为屏障，通过改变裂纹路径来阻止压头下方的裂纹扩展。结果揭示了从沿氧化物晶界的晶间裂纹扩展到通过具有锯齿形图案的纳米孪晶结构的晶内裂纹扩展的转变。