Steel, a generic term for iron-carbon alloys containing between 0.02% and 2.11% carbon. More than 2.11% is iron.
Stainless steels are steels that are characterized by corrosion resistance and have a chromium content of at least 10.5% and a maximum carbon content of 1.2%.
Reason:
Stainless steel is relying on its surface to form a layer of extremely thin and strong and dense stable chromium-rich oxide film (protective film), to prevent oxygen atoms continue to penetrate, continue to oxidize, and obtain the ability to resist corrosion. But for some reason, this film is constantly destroyed, air or liquid and oxygen atoms will continue to penetrate or metal iron atoms continue to separate out, the formation of loose iron oxide, the metal surface is subjected to constant corrosion.
Air humidity, continuous rainy weather, or air containing acidity and alkalinity of the environment is easy to rust. 304 material stainless steel, if the surrounding environment is too poor is also rust.
Solution:
1. With pickling paste or spray to assist its rusted parts to repassivate the formation of chromium oxide film to restore its corrosion resistance, after pickling, in order to remove all the pollutants and acid residues, it is very important to carry out a proper rinse with water. After everything is processed and re-polished with polishing equipment, it can be closed with polishing wax.
2. For localized slight rust spots can also be used 1:1 mixture of gasoline and motor oil with a clean rag to wipe off the rust spots.
3. Sandblasting, cleaning by blasting with glass or ceramic particles, obliteration, brushing and polishing. The use of mechanical methods only cleans its surface and does not change the corrosion resistance of the material itself. It is therefore recommended that mechanical cleaning be followed by re-polishing with polishing equipment and sealing with polishing wax.
