Common Classification of Stainless Steel
Date:2023-02-10View:427Tags:
01. Austenitic stainless steel
The matrix is mainly composed of austenite structure (CY phase) with face-centered cubic crystal structure, non-magnetic, and it is mainly strengthened by cold working (and may lead to certain magnetic properties) stainless steel. The American Iron and Steel Institute is marked with numbers in the 200 and 300 series, such as 304.
02. Ferritic stainless steel
The matrix is mainly ferrite (a phase) with a body-centered cubic crystal structure. It is magnetic and generally cannot be hardened by heat treatment, but cold working can make it slightly strengthened. The American Iron and Steel Institute is marked with 430 and 446.
03. Martensitic stainless steel
The matrix is martensitic (body-centered cubic or cubic), magnetic, and its mechanical properties can be adjusted by heat treatment. The American Iron and Steel Institute is marked with 410, 420 and 440 numbers. Martensite has an austenite structure at high temperature, and when cooled to room temperature at an appropriate rate, the austenite structure can transform into martensite (that is, harden).
04. Austenitic-ferritic (duplex) stainless steel
The matrix has both austenite and ferrite two-phase structure, and the content of less phase matrix is generally greater than 15%. It is magnetic and can be strengthened by cold working. 329 is a typical duplex stainless steel. Compared with austenitic stainless steel, duplex steel has high strength, intergranular corrosion resistance, chloride stress corrosion resistance and pitting corrosion resistance are significantly improved.
05. Precipitation hardening stainless steel
The matrix is austenite or martensite, and can be hardened by precipitation hardening stainless steel. The American Iron and Steel Institute is marked with 600 series numbers, such as 630, which is 17-4PH.
