Stainless steel material. SS304 is a kind of stainless steel, also known as 304 stainless steel. Its chemical composition mainly includes carbon (C), silicon (Si), manganese (Mn), phosphorus (P), sulfur (S), nickel (Ni), chromium (Cr) and other elements. SS304 stainless steel has good corrosion resistance, heat resistance, low temperature strength and mechanical properties, and is widely used in manufacturing chemical equipment, medical instruments, food processing equipment, tableware, architectural decoration and other fields. Its corrosion resistance is mainly due to its high chromium content, which can form a dense chromium oxide passivation film on the surface to prevent further corrosion. At the same time, the addition of nickel also improves the corrosion resistance and toughness of stainless steel.