15Ni-9Co-3.0Mo Maraging Steel

15Ni-9Co-3.0Mo maraging steel is an iron-based superalloy strengthened through precipitation hardening of intermetallic phases (notably Ni₃Mo), rather than carbon content, enabling a combination of very high strength with good toughness and damage tolerance. It is widely used in aerospace and defense applications—particularly in rocket motor cases, landing gear, and fasteners—where the alloy's ability to maintain strength at elevated temperatures combined with excellent fracture toughness and low distortion during heat treatment outweighs the cost premium versus conventional steels. Engineers select this material when weight reduction and structural reliability are critical and fatigue or impact resistance cannot be compromised.