Designation by Standards
| Steel No. | DIN | EN | AISI | JIS | ГОСТ |
| 1.2312 | 40CrMnMoS8-6 | - | P20+S | / | / |
Chemical Composition (in weight %)
| C | Si | Mn | Cr | Mo | Ni | V | W | Others |
| 0.40 | 0.30 | 1.50 | 1.90 | 0.20 | - | - | - | S; 0.005-0.10 |
Description
Cold working tool steel. It is generally supplied hardened and tempered to 880-1080 N/mm2. Higher sulphur content proviedes good machinability at relatively high hardness.Possibility of nitriding. Steel has good polishability.
Applications
Tools for plastics processing and moulds for pressure die casting.
Physical properties (avarage values) at ambient temperature
Modulus of elasticity [103 x N/mm2]: 210
Density [g/cm3]: 7.83
Thermal conductivity [W/m.K]: 33.3
Electric resistivity [Ohm mm2/m]: 0.19
Specific heat capacity[J/g.K]: 0.46
Coefficient of Linear Thermal Expansion 10-6 oC-1
| 20-100oC | 20-200oC | 20-300oC | 20-400oC | 20-500oC | 20-600oC | 20-700oC |
| 11.7 | 13.1 | 13.5 | 14.0 | 14.4 | 14.6 | 14.7 |
Soft Annealing
Heat to 710-740oC, cool slowly in furnace. This will produce a maximum Brinell hardness of 230.
Stress Relieving
Stress relieving to remove machining stresses should be carried out by heating to approx. 650oC, holding for 1-2 hours at heat, followed by air cooling. This operation is performed to reduce distortion during heat treatment.
Hardening
Harden from a temperature of 830-880oC followed by oil or quenching or warm bath quenching 180-220oC. Hardness after quenching is 51 HRC.
Tempering
Tempering temperature: See the data bellow.
Tempering Temperature (oC) vs. Hardness (HRC)
| 100oC | 200oC | 300oC | 400oC | 500oC | 600oC | 700oC |
| 51 | 50 | 48 | 46 | 42 | 36 | 28 |
Forging
Hot forming temperature: 1050-850oC.
Machinability
No data.
Remark
All technical information is for reference only.