
AWS A5.9 – An article to help you understand martensitic stainless steel
Martensitic stainless steels are a type of stainless steel whose mechanical properties (such as hardness and strength) can be significantly modified through heat treatment (such as quenching and tempering). They are members of the stainless steel family known for their strength and hardness. Key Characteristics: 1. Microstructure: Their name derives from their primary microstructure—martensite. This structure, formed by rapidly cooling (quenching) austenite at high temperatures, is a supersaturated solid solution with a body-centered cubic structure, which is the fundamental reason for their high strength and hardness. 2. Chemical Composition: ● Chromium Content: Typically between 11.5% and 18%. Chromium is a key element in providing “stainless” properties, forming a passive film on the surface that resists corrosion. ● Carbon Content: Relatively high, typically between 0.1% and