Through hardening steels
NC40SW
Spécifications
Common name
300M
EU
40NiSiCrMo7
USA
UNS: K44220
AISI: 300M
AISI: 300M
AMS
6417
6419
6419
BS
S155
ASTM grade
32
ASTM std
A579
Composition
C
0.4
Ni
1.8
Cr
0.85
Mo
0.4
Si
1.6
Applications
• Shafts.
• Gears.
• Various mechanical parts.
• Heavily stressed aerospace parts.
Characteristics
• Melting: consumable electrode remelted steel.
• High mechanical properties.
• Good resistance to impact and fatigue.
• Maintains good properties at high temperatures.
Mechanical properties
| Heat treatment |
UTS (N/mm²) |
0,2% YS (N/mm²) |
A (%) |
KCU (J/cm²) |
|---|---|---|---|---|
| T + Rv 600°C | 1450 | 1300 | 14 | 60 |
| T + 2xRv 300°C | 2050 | 1700 | 12 | 50 |
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 |