Abstract Influence of tungsten (W) on the evolution of substructure during creep-fatigue interaction (CFI) and effect of loading mode in terms of continuous cycling (CC) and CFI at 823 K of reduced activation ferritic/martensitic (RAFM) steels has been investigated. Increase in W from 1.4 to 2 wt% resulted in an improvement of 1.6 times of CFI life. Electron back scatter diffraction (EBSD) analysis of CFI deformed specimens demonstrated that the subgrain size was 1.8 times smaller and boundary dislocation density was 3 times higher in case of 2 wt% W steel compared to 1.4 wt% W. It can be deduced that W addition resulted in decrease in the recovery rate and enhancing the CFI life. In context to loading mode, the subgrain size was 1.5 times higher and dislocation density was 2 times lower in case of CC tested specimen with respect to CFI tested. Under CFI, the number of cycles to failure were drastically reduced due to the synergistic damage of cyclic loading and creep deformation.

中文翻译：

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W 的影响和加载模式对还原活化铁素体/马氏体 (RAFM) 钢的亚结构演变的影响

摘要 钨 (W) 在蠕变疲劳相互作用 (CFI) 期间对亚结构演变的影响以及在 823 K 还原活化铁素体/马氏体 (RAFM) 钢的连续循环 (CC) 和 CFI 方面加载模式的影响已得到证实。调查。W 从 1.4% 增加到 2% 重量导致 CFI 寿命提高 1.6 倍。CFI 变形试样的电子背散射衍射 (EBSD) 分析表明，与 1.4 wt% W 钢相比，2 wt% W 钢的亚晶粒尺寸小 1.8 倍，边界位错密度高 3 倍。添加导致回收率降低并提高CFI寿命。在加载模式的背景下，CC 测试样品的亚晶粒尺寸高 1.5 倍，位错密度低 2 倍，相对于 CFI 测试。