Maraging steels
MARVAL18
Spécifications
Common name
Maraging 250
EU
X2NiCoMo18-8-5
USA
UNS: K92890
AMS
6512
AIR
E-Z2NKD18
WL
1.6359
BS
S162
ASTM grade
72
ASTM std
A579
Composition
C
0.03
Ni
18
Mo
5
Ti
0.5
Co
8
Applications
• Aerospace industry:
High strength parts:
– Structural components
– Welded assemblies
– Deck landing hooks
– Rocket motor bodies
– Defence components
– Fasteners.
Characteristics
• Precipitation hardened, maraging type steel, vacuum melted and consumable electrode remelted.
• High yield strength and good impact strength.
• Good weldability.
• Surface hardening by nitriding is possible.
Mechanical properties
| Heat treatment |
UTS (N/mm²) |
0,2% YS (N/mm²) |
A (%) |
|---|---|---|---|
| H | 1070 | 870 | 14 |
| H + V 480°C | 1850 | 1780 | 9 |
Key to heat treatment symbols
| Solution treated | H | Annealed | R |
|---|---|---|---|
| Thermo-mechanical treatment | TM | Quenched and tempered | T+RV |
| Sub-zero treatment | F | Solution treated and aged | H+V |