Designation by Standards
| Steel No. | DIN | EN | AISI | JIS | ГОСТ |
| 1.2311 | 40CrMnMo7 | - | Approx. P20 | / | / |
Chemical Composition (in weight %)
| C | Si | Mn | Cr | Mo | Ni | V | W | Others |
| 0.40 | 0.30 | 1.50 | 1.90 | 0.20 | - | - | - | - |
Description
Prehardened plastic mould steel with good machinability, better than steel grade Mat. No. 1.2312, suitable for texturing.
Applications
Plastic moulds, mould frames for plastic moulds, large injection moulds, pressure casting dies,recipient sleeves.
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]: 34.0 (100oC), 34.0 (150oC), 33.6 (200oC), 32.9 (250oC), 31.9 (300oC), in quenched and tempered condition.
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 air 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
Machinability is relatively good at about 80% that of the W group water hardening steels
Corrosion Resistance
This is a steel alloy and it will corrode or rust unless protected.
Welding
This alloy is weldable by conventional methods. Contact the alloy supplier for details and weld procedures.
Cold working
This steel may be readily cold worked by conventional tooling with the alloy in the annealed condition.
Remark
All technical information is for reference only.