AMS 5645 is a Specification for 321 Stainless Steel, Corrosion and Heat Resistant, Bars, Forgings, and Rings Solution Heat Treated
Type 321 is a titanium stabilized chromium nickel austenitic stainless steel with corrosion resistance similar to 304/304L. This grade is typically used in the 800-1500˚F temperature range where it is stabilized against chromium carbide precipitation by the addition of titanium, which results in the precipitation of titanium carbides. 321 has excellent intergranular corrosion resistance after exposure to this temperature range, and this grade resists oxidation up to 1500˚F and has higher creep and stress rupture properties than 304 SS. It also possesses good low temperature toughness and is non-magnetic in the annealed condition.