Stainless steel types

Stainless steel type for every application

Stainless steels have traditionally been divided into categories since the microstructure has a decisive effect on the properties. The categories are made depending on the chemical composition and secondly the manufacturing steps and parameters that determine the microstructure at room temperature.

Our stainless steel microstructure categories

Outokumpu’s stainless steels can be divided into different categories – the best steel for you depends on the application.

Stay up to date on microstructure group


FERRITIC: The standard ferritic grades are alloyed with chromium (11.2–19%), but with no, or a very small, addition of nickel.

MARTENSITIC AND PH GRADES: For improved strength and hardenability they have a higher carbon content compared to other grades, and nitrogen is sometimes added to further improve strength.

DUPLEX: The duplex grades contribute to high strength and high resistance to stress corrosion cracking. These grades also have a ferritic-austenitic microstructure, with a phase balance of approximately 50/50.

AUSTENITIC: The austenitic grades have good to excellent corrosion resistance, as well as good formability and weldability. This is also the largest group and it is further divided into five sub-groups. These sub-groups are Cr-Mn grades, Cr-Ni grades, Cr-Ni-Mo grades, high performance austenitic grades and high temperature austenitic grades.