AISI Standardization System
In addition to the European standardization system, there are numerous other systems for the standardization of steel products - depending on the country of manufacture and the market. Of particular importance is the system of the "American Iron and Steel Institute" (AISI for short), which is mainly used in North and South America.
In the AISI system, steels are classified with a 3-digit number, which generally distinguishes the 200, 300, 400, 500 and 600 series.
AISI 200 Series> Austenitic chromium-nickel-manganese alloys
AISI 300 Series> Austenitic Chrome-Nickel Alloy
AISI 400 Series> Ferritic and martensitic chromium alloys
AISI 500 series> Heat resistant chrome alloys
AISI 600 Series> Martensitic precipitation hardening alloys