Causes of Hose Corrosion

The metal reacts with oxygen in the atmosphere to form an oxide film on the surface. The iron oxide formed on ordinary carbon steel continues to oxidize, causing the rust to expand and eventually form holes. Carbon steel surfaces can be protected by electroplating with paint or oxidation-resistant metals such as zinc, nickel, and chromium, but, as is known, this protection is only a thin film. If the protective layer is damaged, the steel underneath begins to rust.
The corrosion resistance of stainless steel hoses depends on the chromium content. When the chromium is added to 10.5%, the atmospheric corrosion resistance of the steel increases significantly. However, when the chromium content is higher, although the corrosion resistance can still be improved, it is not obvious. The reason is that alloying steel with chromium changes the type of surface oxide to one similar to that formed on pure chromium metal. This tightly adherent chromium-rich oxide protects the surface from further oxidation. This kind of extremely thin oxide layer, and the natural luster of the stainless steel surface can be seen through it, giving the stainless steel a unique surface. Moreover, if the surface layer is damaged, the exposed steel surface will repair itself by reacting with the atmosphere and re-form the "passivation film" to continue to protect.