摘要
采用宏观微观相结合的方法对护套管及熔覆金属进行了化学成分分析、显微组织分析、裂纹断口金相和扫描电镜分析,通过分析的结果观察到护套管及熔覆金属存在显微组织和硬度分布不均匀的特点,结合理论分析得出护套管断裂性质为疲劳断裂,断裂原因为焊接残余应力在流体的冲刷振动下导致裂纹萌生。并提出护套管在制造上应避免采用焊接。
In this paper, the analysis on the casing and cladding metal were carried out by macro and micro methods, including the chemical composition analysis, microstructure analysis, fracture metallography and scanning electron microscopy(SEM). The results showed that the microstructure and hardness of the casing and cladding metal were not uniform. Combined with theoretical analysis, it was concluded that the fracture property of retaining tube was fatigue fracture.The cause for fracture was welding residual stress, which results in the crack initiation under the vibration of fluid. It was suggested that the welding of the retaining sleeve should be avoided.
出处
《核动力工程》
EI
CAS
CSCD
北大核心
2017年第S2期167-171,共5页
Nuclear Power Engineering
关键词
核电厂
护套管
断裂
显微组织
Nuclear Power Plant
Casing
Fracture
Microstructure
