Stainless steel is an iron alloy to which at least 10.5% chromium has been added to prevent rust. According to its chemical composition and use, stainless steel can be divided into the following categories:
- Chromium-based stainless steel: The main components are chromium and nickel, which have good corrosion resistance and are suitable for manufacturing chemical equipment and marine environment equipment.
- Nickel-cobalt stainless steel: The main components are chromium, nickel and cobalt. It has heat resistance and corrosion resistance, and is suitable for manufacturing under high temperature and high pressure environments.
- Ferritic stainless steel: The main component is chromium, and it does not contain nickel. It has good strength and wear resistance and is suitable for making knives and bearings.
- Austenitic stainless steel: The main components are chromium and nickel, which has good corrosion resistance and is suitable for the manufacture of chemical equipment, medical equipment, etc.
- Duplex stainless steel: Composed of ferrite and austenite phases, it has good strength and corrosion resistance, and is suitable for manufacturing heavy machinery, marine equipment, etc.
In addition, there are martensitic stainless steel, fine stainless steel and other types.