| Equivalent grades |
GB |
DIN |
AISI |
JIS |
|
| 40CrNiMoA |
1.6582 |
4340 |
SNCM8 |
|
| Chemical Composition |
C |
Si |
Mn |
Cr |
Mo |
Ni |
P |
S |
|
| 0.38-0.43 |
0.15-0.35 |
0.60-0.80 |
0.70-0.9 |
0.20-0.30 |
1.65-2.00 |
0.03max |
0.03max |
|
| Available size |
Round Bar |
Diameter |
Length |
| 70-600mm |
2000-6000mm |
| Flat Bar |
Thickness |
Width |
Length |
| 25-400mm |
200-800mm |
2000-6000mm |
| Surface condition |
Black surface/ Grinded/ Machined |
| Annealed hardness |
HBS≤248 |
| Characteristics |
special alloy steel, supplied in quenched and tempered conditions. High strength and tenacity, good hardenability. |
| Applications |
heavily loaded parts for mechanical engineering and motor construction. |
| Heat Treatment |
Forging |
Heat to 1150℃ Hold till uniform.Minimum forging temperature 850℃。Cool slowly in ashes or sand etc. |
| Annealing |
Heat to 830℃-850℃。Cool infurnace. |
| Stress Relieving |
Annealed: Heat to 600℃-650℃。Hardened: Heat to 500℃-550℃。Cool in still air. |
| Hardening |
Heat to 830℃-880℃。Quench in oil or polymer. |
| Tempering |
Heat to 450℃-660℃ cool in still air NB. Tempering within the range 250℃-450℃ will result in temper brittleness and should be avoided. |
