在长期服务后,P92主蒸汽管道的微观结构和机械性能的演变
Haitao Dong1,2, Xianxi Xia1,2, Qinzheng Ma1,2
1Suzhou Nuclear Power Research Institute, Suzhou Xihuan Road 1688, Suzhou 215004, China.
Materials (Basel, Switzerland)
|October 16, 2025
概括
在发电厂中长期使用P92马氏体钢会降低其微观结构和机械性能. 这项研究表明,随着时间的推移,由于微观结构的变化,性和强度显著下降.
科学领域:
- 材料科学 材料科学 材料科学
- 金工业是金工业的一个方面.
- 机械工程 机械工程
背景情况:
- 对于超超临界 (USC) 热电机组来说,P92 马氏体钢非常重要,它提供高温强度和抗爬能力.
- 操作过程中温度升高会导致微观结构的降解,影响钢材的性能和安全性.
- 了解长期服务效应对于保持运营完整性至关重要.
研究的目的:
- 在USC热电机组中长期服务后,研究P92钢的微结构演变和机械性能变化.
- 量化冲击性,抗拉强度和爬行强度随着时间的推移的退化.
- 为了将观察到的微观结构变化与机械性能下降相关联.
主要方法:
- 从主要蒸汽管道中分析P92钢样本,使用时间从30,000小时到93,000小时.
- 对冲击性,抗拉强度 (室内和高温) 和爬行强度进行比较测试.
- 使用扫描电子显微镜 (SEM) 和传输电子显微镜 (TEM) 进行先进的微观结构特征.
主要成果:
- 观察到随着服务时间的增加,机械性能逐渐下降.
- 冲击性下降了大约66.8%,室温抗拉强度下降了9.62%,高温抗拉强度在610°C下降了31.6%.
- 与收到的材料相比,105小时的爬行破裂强度下降了10.4%.
结论:
- 在高温下长时间使用会显著降低P92钢的微观结构和机械性能.
- 微观结构的变化,包括沉积物粗化,马氏石边界降解和谷物粗化,是观察到的恶化原因.
- 这些发现凸显了监测和潜在缓解策略的必要性,以确保USC发电厂中P92钢件的安全性和寿命.
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