LESCALLOY 300M VAC ARC is a low-alloy steel with an excellent combination of high hardenability and high strength coupled with good ductility and good toughness. Its tensile strength ranges from 280,000 to 300,000 psi. It is produced by the vacuum consumable electrode melting process to provide optimum cleanliness and preferred ingot structure. Its applications include aircraft components, pressure vessels and fasteners. This datasheet provides information on composition, physical properties, elasticity, and tensile properties as well as fracture toughness. It also includes information on forming, heat treating, machining, joining, and surface treatment. Filing Code: SA-321. Producer or source: Latrobe Steel Company. Originally published March 1976, revised February 1993.