乏燃料运输罐体旋转凹槽开裂原因分析

某乏燃料运输容器壳体的旋转凹槽在制造过程中发生开裂,为了确定失效原因,防止此类失效事件再次发生,实验对该旋转凹槽的化学成分、力学性能、金相组织和断口形貌进行了分析,确定了断裂原因。结果表明,旋转凹槽的失效模式为氢致延迟开裂,材料中H含量偏高和材料脆化是导致旋转凹槽发生氢致开裂的主要原因。

Fracture cause analysis of rotating groove in the spent fuel tank

The rotating groove in shell of one spent fuel transfer tank was cracked in the manufacture process. To determine the failure cause and prevent the similar failure event happening again, the chemical composition, mechanical properties, metallographic structure, and fracture morphology were analyzed to find out the fracture causes. The results showed that the failure model of the rotating groove was hydrogen-induced delayed cracking. The high content of hydrogen and aging embrittlement were the main reasons to cause hydrogen induced cracking of rotating groove.