核电厂失水事故下锆合金包壳脆化行为及机理研究进展  

Progress in Embrittlement Behavior and Mechanism Study for the Zirconium Alloy Cladding during Loss of Coolant Accident in Nuclear Power Plants

作　　者：卢俊强 陆辉 曾奇锋 LU Junqiang;LU Hui;ZENG Qifeng(Shanghai Nuclear Engineering Research&Design Institute Co.,Ltd.,Shanghai 200233,China)

机构地区：[1]上海核工程研究设计院有限公司,上海200233

出　　处：《核科学与工程》2021年第2期334-347,共14页Nuclear Science and Engineering

基　　金：大型先进压水堆核电站重大专项CAP1400先导组件用锆合金材料关键技术研究资助项目(2017ZX06002005)。

摘　　要：本文通过回顾现有国际上通用的核电厂失水事故(LOCA)安全准则的历史来源和基本原理,阐述了LOCA工况下堆芯可冷却性的内涵,介绍了早期发现的锆合金包壳氧化程度、峰值温度和鼓胀爆破区域的脆化行为及其机理,以及基于这些机理建立的确保LOCA下包壳完整性的基本思想和安全准则。通过归纳总结近些年来核工业界对高燃耗锆合金包壳LOCA工况下脆化行为的研究成果,概述了包括氢增氧致β相脆化、失稳氧化和包壳内表面吸氧等新发现的锆合金包壳脆化现象及其机理,分析了这些新的脆化机理对LOCA工况下堆芯可冷却性的影响,同时还介绍了基于新现象建立的LOCA安全准则的最新进展,这些认识可为我国自主化新锆合金包壳研发及性能试验、核电厂LOCA安全分析提供借鉴,对于抗事故燃料包壳材料在LOCA工况下的性能评价也有一定的参考价值。The history and basic principles of the current safety criteria generally used for the loss of coolant accident(LOCA)in nuclear power plants are reviewed in this paper.The meaning of core coolability during LOCA is explained.The zirconium alloy cladding embrittlemeng behavior and its mechanism for the degree of oxidation(equivalent cladding reacted,ECR),the peak cladding temperature(PCT)and the burst balloon region are introducted.The basic idea of ensuring the integrity of the cladding in LOCA based on these mechanisms found in the early stage is emphasized.Based on the study results of the embrittlement behavior for the high burnup zirconium alloy cladding during LOCA in recent years,the newly discovered embrittlement mechanisms including hydrogen-enhancedβphase embrittlement by oxygen,breakaway oxidation and oxygen pickup from cladding inner surface are summarized.The effects of these new embrittlement mechanisms on the core coolability during LOCA are discussed,and the latest progress of the safety criterion for LOCA is also introduced.These above summaries can be used for the study and performance tests of the zirconium alloy cladding and the LOCA safety analysis of nuclear power plants in China,and also can be used for the performance evaluation of cladding materials for the accident tolerance fuel(ATF)during LOCA.

关 键 词：失水事故 锆合金包壳 脆化 安全准则 

分 类 号：TL341[核科学技术—核技术及应用]