Austenitic Stainless Steel
Stainless steels may be classified by their crystalline structure into three main types: Austenitic, Ferritic and Martensitic. Austenitic steels have austenite as their primary phase (face centered cubic crystal). These are Alloys containing chromium and Nickel (sometimes manganese and nitrogen), structured around the Type 302 composition of iron, 18% chromium, and 8% Nickel. Austenitic steels are not hardenable by heat treatment. The most familiar Stainless Steel is probably Type 304, sometimes called T304 or simply 304. Type 304 surgical Stainless Steel is an austenitic steel containing 18-20% chromium and 8-10% Nickel.