Maraging Steels

Maraging steels are carbon free iron-nickel alloys with the addition of cobalt strengthen steel (C-type), molybdenum, titanium, and aluminum. Maraging steels belong to the category of ultra-high-strength materials which are combined with excellent toughness properties.

Technical Specification Maraging C300 Maraging C350
Nominal Composition  

Ni:18.0 - 19.0
Co: 8.5 - 9.5

Mo: 4.6 - 5.20

Fe: Balance

Ni:18.0 - 19.0
Co: 11.5 - 12.5

Mo: 4.6 - 5.20

Density

0.289 lb./in3, (8.0 g/cm3)

0.292 lb./in3, (8.1 g/cm3)

Modulus of Elasticity (E)

27.5 x 106 psi

29 x 106 psi

Modulus of Rigidity (G)

10.6 x106 psi

11.2 x 106 psi

Coefficient of Expansion

5.6 µin/in.-°F (70°F to 900°F)

6.3 µin/in.-°F (70°F to 900°F)

Electrical Resistivity

68.5 µΩ.in, (174 µΩ.cm)

68.5 µΩ.in, (174 µΩ.cm)

Thermal Conductivity

176Btu-in/ft2hr-°F, (25.3 W/m-K)

176Btu-in/ft2hr-°F, (25.3 W/m-K)

Min Size

0

0

Max Temp

482oC (900oF)

482oC (900oF)

Uses

It is resistant to crack propagation and used in aircraft or high performance racing springs

C350 alloy is heavier and harder than C300 due to higher amounts of Cobalt. Used in high end military applications, such as, recoil springs for heavy guns.