Under normal circumstances, stainless steel won’t rust. However, if the use or maintenance is improper or if stainless steel is under a harsh environment, it will cause stainless steel rust. When you see yellow or orange rust spots on the surface of the steel, that can quickly confirm it is a sign of rust. The stainless steel color plate is very durable under normal conditions and isn’t easy to rust.

Stainless steel has the ability to resist atmospheric and also has the ability to resist corrosion in containing acid, alkali, and salt. However, the size of its resistance to corrosion will change with the chemical constitution of the steel itself, working conditions, and surrounding medium type. 304 stainless steel has absolutely good resistance to corrosion under the atmosphere of dry and cleansing; But if moved to the seaside,304 stainless steel will get rust soon under the sea fog with a large amount of salt. Under the same circumstances, 316 stainless steel performed better. Therefore, not all stainless steel can resist corrosion and rust in any environment.

Stainless steel is formed on a layer of extremely thin, firm, dense, and stable chromium-rich oxide film(protection film) by its surface which obtains the ability to prevent the continuous infiltration and oxidation of oxygen atoms and resist rust. If this film is continuously damaged, oxygen atoms in the air or liquid will continuously infiltrate. And iron atoms in the metal also will continuously separate out. These will form loose iron oxide, and the metal surface will be continuously corroded.