从C70敞车腐蚀状况与钢材化学成分谈耐大气腐蚀钢技术标准

Discussion on Technical Standard of Atmospheric Corrosion Resistant Steel From Corrosion Status of C70 Gondola Car and Chemical Composition of Steel

在简述C70敞车用钢材及相关标准的基础上,针对C70敞车第1次厂修时耐大气腐蚀钢截换量较大的问题,开展了调研工作,统计出厂修时耐大气腐蚀钢的截换量,计算出耐大气腐蚀钢的腐蚀速率。为研究合金元素对耐大气腐蚀钢腐蚀速率的影响,从2018年新造C70敞车钢材取样,采用周期浸润加速腐蚀试验方法对样品进行化验。结果表明,新造C70敞车用耐大气腐蚀钢铜含量普遍接近标准下限要求,这应该是C70敞车钢材腐蚀速率较快的主要因素。建议提高铁路货车用耐大气腐蚀钢标准中铜含量下限,以降低钢材腐蚀速率,进而减少厂修钢材截换量,降低厂修费用。

Based on brief introduction of C70 gondola steel and related standards,the research work is carried out to solve the problem of large cutting offs of atmospheric corrosion resistant steel in the first factory repair of C70 gondola car.The cutting off amount of atmospheric corrosion resistant steel in the factory repair was counted and the corrosion rate of atmospheric corrosion resistant steel was calculated.In order to study the effect of alloying elements on corro sion rate of atmospheric corrosion resistant steel,samples of new C70 gondola steel in 2018 were tested by periodic soaking accelerated corrosion test method.The results show that the copper content of the steel for newly built C70 gondola car is generally close to the lower limit of the standard,which should be the main factor for the fast corrosion rate of C70 gondola car steel.It is suggested that the lower limit of copper content in the standard of atmospheric cor rosion resistant steel for railway freight cars should be raised so as to reduce the corrosion rate of steel,thereby reduc ing the interception amount of steel for factory repair and reducing the cost of factory repair.