摘要
对核岛主设备不锈钢带极埋弧堆焊层剥离机理进行研究,结果表明:低合金钢母材上的不锈钢带极埋弧堆焊层过渡区出现平均厚度为25μm的硬化层,硬化层为高硬度、低塑性的板条马氏体组织;过渡区存在Ⅱ型边界,硬化层上存在气孔,Ⅱ型边界和气孔是堆焊层发生剥离的内因;随着堆焊层数的增加,接头界面残余应力增大,堆焊层数达到6层时,残余应力为380 MPa,过渡区的Ⅱ型边界在较大的残余应力作用下作为裂纹源扩展导致不锈钢堆焊层剥离。堆焊层界面较大的残余应力是剥离发生的外因。
The disbonding mechanism of stainless steel cladding by submerged arc welding with band-electrode was studied.The results reveal that hardened layer was found in transition zone of the cladding,and the average thickness is 25μm.The hardened layer with higher hardness and lower toughness is lath martensite.Type-Ⅱgrain boundary and porosity appeared in the transition zone and martensite layer respectively is the internal cause for disbonding.Numerical simulation results indicate that the residual stress increases with the increase of number of the cladding layers,and the residual stress reaches 380 MPa when cladding layers reach 6.Type-Ⅱgrain boundary causes disbonding of the stainless steel cladding as the crack source expands under large residual stress.Greater residual stress is the external cause for disbanding.
作者
杨乘东
茹祥坤
唐伟宝
YANG Chengdong;RU Xiangkun;TANG Weibao(Shanghai Electric Nuclear Power Group Co.,Ltd.,Shanghai 201306,China;Shanghai Engineering Research Center of Nuclear Power Equipment Welding and Examination,Shanghai 201306,China)
出处
《压力容器》
北大核心
2023年第6期22-26,共5页
Pressure Vessel Technology
关键词
核岛主设备
不锈钢
带极埋弧堆焊
硬化层
Ⅱ型边界
剥离
nuclear island main equipment
stainless steel
cladding by submerged arc welding with band-electrode
hardened layer
type-Ⅱgrain boundary
disbonding
