Abstract CRUCIBLE 321 is a non-hardenable austenitic chromium-nickel steel which is particularly adaptable for parts fabricated by welding without postweld annealing for use at temperatures between 800 and 1500 F. This grade is non-magnetic in the annealed condition but is slightly magnetic when cold worked. Among its many applications are aircraft-engine exhaust manifolds, furnace parts and expansion joints. This datasheet provides information on composition, physical properties, hardness, elasticity, 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-426. Producer or source: Crucible Specialty Metals Division, Colt Industries.