ABSTRACT The determination of creep properties of the components operating at high temperatures in thermal power plants is an enormous concern for safe life assessment. In this study, a series of miniature creep and tension tests were carried out with service-exposed (54,750 h and 68,550 h at 650 °C) and virgin Super304H steel materials. The power law creep behaviour, creep rupture life, and tensile properties were compared among the virgin and service-exposed materials. The creep strength of the 54,750-h-serviced material was comparable to that of the virgin material, while it decreased significantly for the 68,550-h-serviced material. The degradation of the properties of the service-exposed material was discussed based on metallurgical analyses and precipitation mechanisms.

中文翻译：

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服役中的 Super304H 钢锅炉管的蠕变变形和破裂行为

摘要 热电厂高温下运行部件的蠕变特性的确定是安全寿命评估的一个重大问题。在这项研究中，对暴露在役（650 °C 下 54,750 小时和 68,550 小时）和全新 Super304H 钢材料进行了一系列微型蠕变和拉伸试验。比较了原始材料和服务暴露材料的幂律蠕变行为、蠕变断裂寿命和拉伸性能。使用时间为 54,750 小时的材料的蠕变强度与原始材料相当，而使用时间为 68,550 小时的材料的蠕变强度显着降低。基于冶金分析和沉淀机制讨论了服务暴露材料的性能退化。