接触网部件材料在模拟典型大气环境介质中的腐蚀——热浸镀锌材料的腐蚀(I)

采用腐蚀失重法与显微镜技术,研究了电气化铁路接触网热浸镀锌部件材料在模拟典型大气环境(海洋环境、工业环境、城市环境)介质中的腐蚀及其形貌。结果表明,热浸镀锌材料在模拟城市大气环境介质中的腐蚀最为严重,工业环境次之,海洋环境腐蚀最轻。二次加工与成型会引起镀锌层局部破损致使基材局部暴露与镀锌层形成电偶对,会加重热浸镀锌部件的腐蚀,且破损面积越大腐蚀越严重。同样,热浸镀锌部件与不锈钢紧固件耦接会形成电偶腐蚀,也会加重热浸镀锌部件的腐蚀。建议针对电气化铁路各段不同的大气环境,选择不同的接触网零部件材料、或者采用相应的防腐措施。在接触网构件加工和装配过程中,建议改进加工工艺程序,避免热浸镀锌部件的二次加工或者成型;建议采用绝缘措施,以达到热浸镀锌部件与不锈钢紧固件之间的绝缘耦接,避免电偶腐蚀发生。

Corrosion of the Fitting Material of Overhead Contact System in Media simulating Typical Atmospheric Environments--the Corrosion of Hot Dip Galvanized Material (1)

In this work, the corrosion and morphology of galvanized carbon steel parts, which is used as the fitting material of overhead contact system in the media simulating atmospheric environments （marine environment, industry environment, urban environment） have been studied by weight-loss method in conjunction with Microscopy technique. The results show that the corrosion rate of galvanized carbon steel in the medium simulating urban atmospheric environment is highest, higher in the medium simulating industry atmospheric environment and lower in the medium simulating marine atmospheric environment. Secondary processing and formation caused local damages of galvanized layer, resulting in serious corrosion of galvanized carbon steel parts. The larger the damage area is, the more serious the corrosion is. Similarly, galvanized carbon steel parts fixed with threaded bolt made of stainless steel would form a galvanic corrosion, which also can aggravate the corrosion of galvanized carbon steel parts. It was suggested different materials or corrosion protection measures should be used for the fitting of overhead contact system in different atmospheric environment. Meanwhile, the secondary processing of galvanized carbon steel parts should be avoided. Insulation measures should be taken to avoid galvanized carbon steel parts to be directly fixed with threaded bolt made of stainless steel.