Abstract Crucible AFC-77 is a precipitation-hardenable martensitic stainless steel which retains good mechanical properties at operating temperatures up to 1200 F. The alloy can be heat treated to high strength levels while exhibiting good oxidation and corrosion resistance. It is recommended for high temperature structural applications as well as hot work applications such as extrusion tooling, die casting dies and glass molds. This datasheet provides information on composition, physical properties, hardness, and tensile properties as well as fracture toughness and creep. It also includes information on high temperature performance and corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: SS-209. Producer or source: Crucible Steel Company of America.