Lescalloy 6305 VAC-ARC steel is a modified AISI 4140 steel with higher molybdenum content and additional vanadium. The alloy is most frequently used in the quenched and tempered condition. Jet engine shafting is a typical application. This datasheet provides information on composition, physical properties, and tensile properties. It also includes information on forming, heat treating, machining, and joining. Filing Code: SA-498. Producer or source: Latrobe Steel Company.