"All stainless steels contain chromium, 10% or more. Ferritic stainless steels may contain small amounts of other elements such as titanium or molybdenum, but austenitic stainless steels also contain significant amounts of nickel. As a result, the crystal structure of austenitic stainless steels is face-centered cubic, while the structure of ferritic stainless steels is body-centered cubic, as in mild steels. While both are more corrosion resistant than typical mild steels, they are quite different in other ways. Ferritic stainless steels are magnetic, austenitics are not. Austenitic stainless steels are more corrosion resistant than ferritic. They are also tougher and more ductile. However, they are a lot more expensive."
