Steels for carburizing
FDG
FDGW
Spécifications
EU
20NiCrMo13-4
USA
UNS: K41910
AMS
6492
6493
6493
ISO Symbol
20NiCrMo13-4
ISO Num
1.6660
Composition
C
0.2
Ni
3.2
Cr
1
Mo
0.5
Applications
• Gears subjected to high stresses, diverse parts subject to wear and fatigue in service.
• In the quenched and tempered condition: safety-critical parts.
Characteristics
• High mechanical properties.
• Good fatigue strength.
• After carburizing, quenching and tempering, the surface hardness is around 700 HV.
• For some carburizing applications, oil quenching can be replaced with gas pressure quenching in order to minimise distortion due to the heat treatment.
The mechanical properties thus obtained are equivalent to those of the FADH grade.
Mechanical properties
| Heat treatment |
UTS (N/mm²) |
0,2% YS (N/mm²) |
A (%) |
KV (J) |
|---|---|---|---|---|
| T + Rv 150°C | 1450 | 1100 | 13 | 130 |
| 1300 | 1000 | 13 | 110 |
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 |