理化检验-物理分册2026，Vol.62Issue(8)：45-49,5.DOI:10.11973/lhjy-wl260183
核电厂低压氮气系统螺柱开裂原因
Causes of stud cracking in the low-pressure nitrogen system of a nuclear power plant
高腾飞 1陈文浩 2郭凯 1李心刚 1罗真 3翟新年 3侯桂林3
作者信息
- 1. 大亚湾核电运营管理有限责任公司,深圳 518000
- 2. 苏州热工研究院有限公司,苏州 215000
- 3. 中核凯利深圳核能服务股份有限公司,深圳 518000
- 折叠
摘要
Abstract
A brittle fracture occurred in the smooth rod section of the A2-70 steel stud bolts on the low-pressure nitrogen pipeline flange of a coastal nuclear power plant.The causes of the stud fracture were analyzed using methods such as macroscopic observation,metallographic examination,chemical composition analysis,hardness testing,scanning electron microscopy and energy spectrum analysis,chemical and intergranular corrosion tests.The results show that the stud underwent significant cold working deformation during production and was not subjected to solution heat treatment,which led to insufficient dissolution of internal carbides,which formed a continuous network-like distribution along the grain boundaries.The absence of solution treatment significantly reduced the stud's resistance to pitting corrosion and markedly increased its susceptibility to intergranular corrosion.The narrow and enclosed gap between the smooth rod section of the stud and the flange contact surface accumulated rainwater and remained exposed to high-humidity marine atmosphere,caused continuous corrosion in the gap area.Under the tensile stress experienced during service,the stud ultimately fractured through intergranular stress corrosion.关键词
螺柱/固溶热处理/碳化物/沿晶应力腐蚀开裂/电化学试验Key words
stud/solution heat treatment/carbide/intergranular stress corrosion cracking/electrochemical testing分类
通用工业技术引用本文复制引用
高腾飞,陈文浩,郭凯,李心刚,罗真,翟新年,侯桂林..核电厂低压氮气系统螺柱开裂原因[J].理化检验-物理分册,2026,62(8):45-49,5.
