UDIMAR B-300 is an 18% nickel maraging steel having excellent toughness and ductility at high strength levels. It is a fabricable and weldable ultra-high strength alloy steel combining the mechanical properties derived from precipitation hardening and martensitic transformation. It has increased cobalt content compared with UDIMAR B-250 (Alloy Digest SA-206, February 1967). This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties, and compressive and shear strength as well as fracture toughness, creep, and fatigue. It also includes information on high temperature performance and corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: SA-244. Producer or source: Special Metals.