Maraging 300

Principal Design Features

Maraging 300 alloy is a very high strength iron base, nickel , molybdenum, cobalt alloy. It may be age hardened to a strength level of 300 ksi ultimate with a hardness on the order of Rockwell C 53.


Used for very high strength structural applications such as aircraft land gear components.


Machinability is good, similar to that for 304 stainless steel.


Maraging 300 steel has good ductility and is readily formed by conventional methods.


The alloy is weldable by conventional methods, much the same as for 304 stainless steel.

Heat Treatment

Maraging steel is not heat treatable for hardening except by aging. See “Aging”.


The alloy may be forged as for stainless 304 alloy.

Hot Working

Hot working of maraging steel may be done at temperatures in the 500 to 200 F range. Prolonged exposure at these temperatures may result in some age hardening. However a full aging treatment should be given.

Cold Working

The alloy is readily cold worked by conventional methods.


Annealing, if required after cold working, can be done at 1900 F followed by rapid air cooling.


The high strength and hardness properties are a result of an aging heat treatment at 900 F


Not applicable to this alloy.


Maraging 300 hardens by cold working and by aging – see “Aging”.

Density: 0.289

Specific Gravity: 8

Specific Heat: 0.108

Melting Point: 2575

Thermal Conductivity: 136

MCTE: 5.6

MoETensile: 27.5


To Send a Request for Quote, please Click Here, call 973.276.5000, or fax (973) 276 – 5050