GIS用不锈钢板簧在进行200次操作试验时发生断裂，通过宏观分析、化学成分分析、断口分析、金相分析、力学性能试验等方法对板簧断裂原因进行了分析。结果表明：板簧表面存在的微小缺陷、显微组织中的沟状组织及夹杂物、含有氯离子的腐蚀环境以及应力共同作用，导致板簧发生了应力腐蚀开裂。最后针对板簧断裂原因提出了预防措施。

The stainless steel plate spring in GIS fractured during 200 cycles' operation test. The fracture causes of the plate spring were analyzed by macroscopic analysis, chemical composition analysis, fracture analysis, metallographic analysis and mechanical property test. The results show that the micro-defects on the surface of the plate spring, the grooves and inclusions in the microstructure, the corrosive environment containing chloride ions and the stress acted together and resulted in the stress corrosion cracking of the plate spring. Finally, preventive measures were put forward for the fracture causes of the plate spring.