摘要
为了研究核电给水除氧器系统管线不锈钢焊口批量开裂机理,取样进行了理化分析、裂纹形貌观察。分析表明,断口扩展区发现了疲劳辉纹,焊缝、热影响区塑性、韧性显著低于母材,为裂纹扩展提供了有利路径,交变载荷或在应力集中交互作用下提供了裂纹萌生条件和扩展动力,导致焊口早期开裂。根据开裂分析过程中发现的问题,提出了改进措施,确保机组安全稳定运行。
in order to research the batch cracking mechanism of stainless steel welded joints in nuclear feed water deaerator system, physical and chemical analysis and crack morphology observation were carried out. The results show that the fatigue profile is found in the fi-acture zone, and the plasticity and toughness of the weld HAZ are significantly lower than those of the base metal, providing a favorable path for crack propagation. Alternating loads may provide crack initiation conditions and extended forces under stress concentration interaction, leading to early cracking of welds. According to the problems found in the cracking analysis process, the improvement measures are put forward to ensure the safe and stable operation of the unit.
出处
《中国特种设备安全》
2017年第5期72-75,共4页
China Special Equipment Safety
关键词
核电
疲劳裂纹
失效分析
不锈钢
Nuclear Fatigue crack Failure analysis Stainless steel
