核用传热管表面划伤致应力腐蚀失效问题及研究进展

An Overview on the Stress Corrosion Cracking Caused by Scratches on Steam Generator Tubes

综述了金属表面划伤的理论模型、划伤区的变形特点、影响因素及其对应力腐蚀影响的研究进展,介绍了压水堆核电站传热管的服役环境和表面划伤案例、来源及工程对策,讨论了表面划伤对蒸汽发生器传热管应力腐蚀失效的影响及研究进展。总结现有研究中亟待解决的问题,提出对进一步完善表面划伤理论模型、深入认识划伤影响区损伤特点和应力腐蚀机制、传热管表面划伤安全阈值评估、表面修复工艺等研究方向的展望。

This paper summarizes the theoretical model of scratches on the metal surface,the characteristics of the deformation zone caused by scratch and its impacts on stress corrosion cracking.The failure cases caused by scratches on steam generator tubes in pressurized water reactor nuclear power plants are introduced,and so are the sources of surface scratches and the corresponding repair methods or strategies.The effects of surface scratches on the stress corrosion failure of steam generator tubes and the research progress are discussed.The potential research topics and directions in the future are also proposed,such as further improving the theoretical model of surface scratches,deepening the understanding of the damage characteristics and stress corrosion mechanism in the affected area by scratches,the safety scratch threshold evaluation and surface repair methods.