由于不锈钢的自钝化特性,破坏部位可以再钝化,保护材料的擦伤部位不继续腐蚀,避免形成点蚀。但由格架方筒腐蚀部位的产物、表面污染物和贴膜检测结果可知,材料表面存在S、Cl等腐蚀性元素离子,钝化膜破坏部位难以形成再钝化,而产生优先溶解形成小孔,发生点蚀。 Due to the self-passivation properties of stainless steel, the destruction of the site can be passivated, scratching parts of protective materials do not continue to corrosion, to avoid the formation of pitting. However, the corrosion products of square square tube, surface contaminants and film test results show that there are S, Cl and other corrosive elemental ions on the surface of the material, the passivation film is difficult to form the damaged parts and then passivate, which will preferentially dissolve to form small holes , Pitting occurs.