There are many types of stainless steel with different properties. Common classification methods are:
Classification according to the structure of steel, such as martensitic stainless steel, ferritic stainless steel, austenitic stainless steel and duplex stainless steel.
It is classified according to the main chemical composition in steel or some characteristic elements in steel, such as chromium stainless steel, chromium nickel stainless steel, chromium nickel molybdenum stainless steel, ultra-low carbon stainless steel, high molybdenum stainless steel, high purity stainless steel, etc.
It is classified according to the performance characteristics and uses of steel, such as nitric acid (nitric acid grade) stainless steel, sulfuric acid resistant stainless steel, pitting corrosion resistant stainless steel, stress corrosion resistant stainless steel, high-strength stainless steel, etc.
According to the functional characteristics of steel, such as low-temperature stainless steel, non-magnetic stainless steel, free-cutting stainless steel, superplastic stainless steel, etc.
At present, the most commonly used classification method is to classify according to the structural characteristics of steel and the characteristics of chemical composition of steel and the combination of the two. For example, the current stainless steel is divided into: martensitic steel (including martensitic Cr stainless steel and martensitic Cr-Ni stainless steel), ferritic steel, austenitic steel (including Cr-Ni and Cr-Mn-Ni stainless steel) (-N) austenitic stainless steel), dual-phase steel (α+γ dual-phase) and precipitation hardening steel, or divided into two categories: chromium stainless steel and chromium-nickel stainless steel.
