核电厂高强度螺栓的氢脆和应力腐蚀问题  

Problems of Hydrogen Embrittlement and Stress Corrosion of High Strength Bolts Used in Nuclear Power Plants

作　　者：张忠伟[1] 赵彦芬[1] 赖云亭[1] 左敦桂 陈志林[1] 刘忠[1] ZHANG Zhongwei;ZHAO Yanfen;LAI Yunting;ZHUO Dungui;CHEN Zhilin;LIU Zhong(Suzhou Nuclear Power Research Institute Co.,Ltd.,Suzhou 215004,Jiangsu Province,China)

机构地区：[1]苏州热工研究院有限公司,江苏省苏州市215004

出　　处：《中国电机工程学报》2021年第9期3259-3272,共14页Proceedings of the CSEE

摘　　要：高强度螺栓发生氢脆(hydrogen embrittlement,HE)和应力腐蚀(stress corrosion,SCC)事件直接威胁核电厂安全运行。该文介绍国内核电厂高强度螺栓HE和SCC问题现状,分析了失效机理、规律和控制难点,给出对策建议。在2015—2019这5年时间里,国内核电厂共发生了 22起高强度螺栓HE和SCC事件,其中,内氢脆(internal hydrogenembrittlement,IHE)、阳极溶解型应力腐蚀(anode dissolution type of stress corrosion cracking,AD-SCC)和氢脆型应力腐蚀(hydrogen embrittlement type of stress corrosion cracking,HE-SCC)事件分别占比18%、27%和55%,与强度过高有关的事件占比55%。HE和SCC问题与时间高度关联,具有明显的慢性、偶发和随机性特征,已经成为国内核电厂高强度螺栓安全服役的主要威胁,应引起监管部门关注。长远看,建立针对高强度螺栓HE和SCC问题的行业标准、研究和使用可以有效阻断腐蚀介质到达螺栓表面的新方法、开发新型抗HE和SCC的高强度螺栓,是治理该问题的长久之策。Hydrogen embrittlement(HE) and stress corrosion(SCC) of high strength bolts directly threaten the safe operation of nuclear power plants. This paper introduced the status quo of the HE and SCC of high strength bolts in domestic nuclear power plants, and analyzed the failure mechanics, regularity and controlling difficulties. In the five years from 2015 to 2019, there were a total of 22 high strength bolts HE and SCC incidents in domestic nuclear power plants. The proportions of internal hydrogen embrittlement(IHE), anode dissolution type of stress corrosion cracking(AD-SCC) and hydrogen embrittlement type of stress corrosion cracking(HE-SCC) incidents were 18%, 27% and 55% respectively, and 55% of incidents related to excessive high tensile strength. HE and SCC are highly related to time, with obvious chronic, sporadic and random characteristics, which have become the biggest threat to the safe service of high strength bolts in domestic nuclear power plants, and should be concerned by regulatory authorities. The standards for special bolts for nuclear power plants, general bolts standards, conventional material standards, and national regulatory documents have not specifically focused on HE and SCC issues. In the long run, establishing special standards for HE and SCC of high strength bolts, studying and using new methods that can effectively block the corrosive medium from reaching the bolts surface, and researching new anti-HE and SCC high strength bolts are long-term ways to manage HE and SCC problems.

关 键 词：氢脆 应力腐蚀 主要威胁 强度 慢性病 

分 类 号：TG178[金属学及工艺—金属表面处理]