15Ni-9Co-3.0Mo-0.8Ti Maraging Steel

15Ni-9Co-3.0Mo-0.8Ti is a high-strength maraging steel—an iron-nickel age-hardenable alloy designed for applications demanding exceptional strength-to-weight ratios and fracture toughness without brittleness. This specific composition (18% grade class) is hardened through precipitation of intermetallic phases during aging rather than carbon content, making it machinable in the annealed state yet capable of achieving very high strength levels. Industries rely on maraging steels where weight savings and damage tolerance are critical, particularly in aerospace structures, tooling, and high-performance applications where conventional high-carbon steels would be too brittle or difficult to machine.