Carbon and Low-alloy High-strength Steel provide greater environmental corrosion resistance and are stronger than convention carbon steel,also very ductile, highly formable and easy to weld.Carbon and Low-alloy High-strength Steel steels are not typically made to meet a certain chemical composition, instead they are known to meet specific mechanical properties. Carbon and Low-alloy High-strength Steelspecification is intended primarily for use in structural members, where savings in weight and added durability are critical.BBN steel Carbon and Low-alloy High-strength Steel main steel grade:S355JR,A572Gr.50,St52-3,SM570.