Abstract P92 steel is used as a piping material in ultra super critical power plants that can be operated at steam temperatures up to 650°C. The changes in the martensitic microstructure of P92 steel must be evaluated thoroughly before it is put into actual service. In this study, indigenously developed P92 steel was used. The steel was subjected to normalizing and tempering heat treatments in the range of 1,040–1,060°C and 740–780°C. The changes in the microstructure were evaluated and creep-rupture properties were studied at test temperatures of 600 and 650°C. Although normalizing temperatures influenced the microstructure and creep strength marginally, the change in tempering temperatures led to significant changes. The creep rupture strength at 600°C was influenced largely by the changes in the dislocation substructure, while the precipitation of Laves phases was a significant observation made for 650°C test temperature. Proposed mechanisms for the microstructural evolution and its consequences on the rupture life are discussed in this study.

中文翻译：

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正火和回火温度对P92钢蠕变性能的影响

摘要 P92 钢用作超超临界电厂的管道材料，可在高达 650°C 的蒸汽温度下运行。P92钢在投入实际使用前，必须对其马氏体组织的变化进行彻底的评估。在这项研究中，使用了本土开发的 P92 钢。钢在 1,040-1,060°C 和 740-780°C 范围内进行正火和回火热处理。在 600 和 650°C 的测试温度下评估了微观结构的变化并研究了蠕变断裂性能。尽管正火温度对微观结构和蠕变强度影响很小，但回火温度的变化会导致显着变化。600℃蠕变断裂强度主要受位错亚结构变化的影响，而 Laves 相的沉淀是 650°C 测试温度下的一个重要观察结果。本研究讨论了微观结构演化的拟议机制及其对破裂寿命的影响。