Different series of stainless steel

Stainless steel is usually divided into 201, 202, 301, 304, 309s, 310s, 410, 420, 431 and other models. Among them, 201, 202, 301, 304, 309s, 310s belong to austenitic stainless steel, does not contain magnetic, can resist a variety of media corrosion. 410, 420, 431 are martensitic stainless steels, which have magnetic properties and high strength, but poor plasticity and weldability.

1.What is stainless steel

Stainless steel is the abbreviation of stainless steel, resistant to air, steam, water and other weak corrosive media or stainless steel; The steel that is resistant to chemical corrosion media (acid, alkali, salt and other chemical etching) is called acid-resistant steel.

Stainless steel is often divided into martensitic steel, ferritic steel, austenitic steel, austenitic ferritic (duplex) stainless steel and precipitation hardening stainless steel, etc. In addition, according to the composition can be divided into: chromium stainless steel, chromium nickel stainless steel and chromium manganese nitrogen stainless steel.

2.The corrosion resistance of stainless steel decreases with the increase of carbon content, therefore, the carbon content of most stainless steel is low, the maximum is not more than 1.2%, and the ωc (carbon content) of some steel is even lower than 0.03% (such as 00Cr12). The main alloying element in stainless steel is Cr (chromium), and only when the Cr content reaches a certain value, the steel has corrosion resistance. Therefore, the general Cr (chromium) content of stainless steel is at least 10.5%. Stainless steel also contains Ni, Ti, Mn, N, Nb, Mo, Si, Cu and other elements.