一例放电事故造成硬氧膜脱落的原因分析

Reason analysis of hard anodic oxide film falling off caused by a discharge accident

针对一起特高压开关放电事故中电连接硬质阳极氧化膜焚化、脱落的问题,采用现场环境分析、工艺加工模拟以及对于脱落前后的硬质阳极氧化膜的成分进行宏观和微观分析的方法进行研究。结果表明,此次硬质阳极氧化膜脱落及焚化的主要原因为:放电产生的电弧将气室内六氟化硫气体分解成强腐蚀性有毒气体,并释放出大量的热量,导致氧化膜出现裂纹。产生的气体通过裂纹渗入氧化膜底部,与氧化膜发生物理、化学反应,从而造成氧化膜的脱落与焚化,研究结果为今后分析此类问题提供了依据。

Aiming at the problem of incineration and falling off of hard anodic oxide film of electrical connection in an ultra-high voltage switch discharge accident,the methods of on-site environmental analysis,process simulation and macro and micro analysis of the composition of hard anodic oxide film before and after falling off are used to study. The results show that the main reason for the falling off and incineration of the hard anodic oxide film is that the arc generated by the discharge decomposes the sulfur hexafluoride gas in the gas chamber into highly corrosive toxic gas and releases a large amount of heat,resulting in cracks in the oxide film. The generated gas penetrates into the bottom of the oxide film through the crack and reacts physically and chemically with the oxide film,resulting in the falling off and incineration of the oxide film. The research results provide a basis for the analysis of such problems in the future.