MARAGING (C) 350 | UNS K93120 | Mil-S-46850D | AMS 6515 | Vascomax C350 | DIN 1.6356
Maraging is a 18% nickel, cobalt strengthened steel (C-type), with excellent mechanical properties, workability and heat treatment characteristics.
Alloy steels are designated by AISI four-digit numbers. They comprise different kinds of steels having composition exceeding the limitations of B, C, Mn, Mo, Ni, Si, Cr, and Va set for carbon steels. They quickly respond to mechanical and heat treatments than the carbon steels.
Typical applications for maraging include missile and rocket motor cases, landing and takeoff gear, munitions, aerospace, extrusion tooling, die casting, high performance shafting, gears and fasteners.
- C : 0.03 max
- Mn : 0.10 max
- Si : 0.10 max
- P : 0.10 max
- S : 0.10 max
- NI : 18.00-19.00
- Co : 11.50-12.50
- Mo : 4.60-5.20
- Ti : 1.30 -1.60
- Al : 0.05-0.15
- Cr : 0.50 max
- Cu : 0.50 max
Material Melt Method Maraging melt method is a VIM (Vacuum Induction Melt) + VAR (Vacuum Arc Remelt)
The physical properties of maraging 350 alloy steel are listed in the following table.
|Density||8.08 g/cc||0.292 lb/in³|
As Shipped Condition: Maraging is supplied in the annealed and descaled condition. The alloy is very tough, relatively soft ((36 Rc Max.), therefore, readily machined and formed.
Minimum Properties after Aging:
- Hardness ……………… 56 Rc
- Charpy V-notch ……… 6 ft/lbs. min
- Reduction of Area ……. 25%
- Elongation ……………. 2.8%
- Yield Strength …………. 330 ksi
- Fracture Toughness ….. 25
The mechanical properties of annealed maraging 350 alloy steel are outlined in the following table.
|Tensile strength||1140 MPa||165000 psi|
|Yield strength (@ strain 0.200%)||827 MPa||120000 psi|
|Bulk modulus (typical for steel)||140 GPa||20300 ksi|
|Shear modulus (estimated from elastic modulus)||77 GPa||11200 ksi|
|Elastic modulus||200 GPa||29000 ksi|
|Elongation at break (in gage length 4.5 times the square root of the area)||18%||18%|
|Reduction of area||70%||70%|
Heat Treatment Aging Process (Non Die Casting Applications) Material is to be heat treated to 900 F +/- 10 holding at temperature for 6 hours then cooling at room air temperature. During the aging treatment maraging shrinks uniformly and predictably on all dimensions .001 in/in
Heat Treatment Aging Process (Die Casting Applications) Following the rough machining of the die, anneal at 1500-1525 F for 1 hour per inch of thickness is recommended. After finish machining , an aging heat treatment of 980-1000 F for 6 hours is recommended.
Maraging steel in the annealed condition is comparable to 4340. However, when maraging is aged, the type of cutting tool and speeds change. Rigid equipment, firm tool supports, sharp tools and abundant coolant are essential.
Maraging is weld able without preheat, in both the annealed and aged condition. Only an aging heat treatment is needed to restore in the weld.
- UNS K93120
- AMS 6515
- Vascomax C350
- DIN 1.6356
FountainHead Alloys is ISO 9001:2015 approved. © FountainHead Alloys 1996