Structural alloy steel 30NiCrMo12, 30NCD12, 32NiCrMo12-5, 32NiCrMo10-4, 1.6655, 1.6743 for heat treatment for particularly stressed parts for aircraft industry according to UNI 6924.
| Standards | Steel Grades | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Chemical Composition % | |||||||||
| C: | Mn: | Si: | P: | S: | Cr: | Ni: | Mo: | V: | |
| UNI 6924 | 30NiCrMo12 - 30 NiCrMo 12 | ||||||||
| 0.28 - 0.34 | 0.5 - 0.8 | <0.4 | <0.025 | <0.020 | 0.6 - 0.9 | 2.7 - 3.2 | 0.40 - 0.60 | - | |
| AFNOR | 30NCD12 - 30 NCD 12 | ||||||||
| 0.25 - 0.35 | 0.15 - 0.55 | 0.1 - 0.4 | <0.030 | <0.025 | 0.7 - 1.1 | 2.8 - 3.2 | 0.25 - 0.45 | - | |
| DIN | 32NiCrMo12-5 - 32 NiCrMo 12-5 - 1.6655 | ||||||||
| 0.29 - 0.36 | 0.25 - 0.50 | 0.15 - 0.40 | <0.025 | <0.025 | 1.2 - 1.5 | 2.8 - 3.0 | 0.30 - 0.40 | - | |
| DIN | 32NiCrMo10-4 - 32 NiCrMo 10-4 - 1.6743 | ||||||||
| 0.28 - 0.36 | 0.30 - 0.60 | 0.15 - 0.35 | <0.035 | <0.035 | 0.9 - 1.2 | 2.4 - 2.7 | 0.35 - 0.55 | - | |
| BS | 826M31 - 826 M 31 | ||||||||
| 0.27 - 0.35 | 0.45 - 0.70 | 0.10 - 0.40 | <0.035 | <0.040 | 0.5 - 0.8 | 2.3 - 2.8 | 0.45 - 0.65 | - | |
| ASTM | A723 Grade 2 - UNS K34035 | ||||||||
| <0.40 | <0.90 | <0.35 | <0.015 | <0.015 | 0.8 - 2.0 | 2.3 - 3.3 | 0.30 - 0.50 | <0.2 | |
Steel 30NiCrMo12 - application
30NiCrMo12 steel is a typical alloy construction grade for heat treatment - hardening and tempering, which is characterized by very high mechanical properties, hardness, load resistance and variable pressure.
Steel is used i.e. in aviation as well as for components and particularly responsible components of machinery, equipment, vehicles such as axles, couplings, shafts, levers or connecting rods.
Mechanical properties of 30NiCrMo12 steel
- Tensile strength, Rm: 880 - 1180 MPa
- Yield point, Re: > 685 MPa
- Elongation, A: 14%
- Notch toughness, KCU: 35 - 40 J
- Hardness in softened state < 260 HB
Heat treatment - processes and temperatures
- Softening annealing with isothermal transformation at 800℃, with cooling at 620℃ for 24 hours
- Normalizing annealing at 840 - 870℃
- Relief annealing at 640 - 670℃
- Hardening with cooling in oil at the temperature of 830 - 850 ℃
- Tempering at 550 - 650℃
In the above mentioned grades the company provides:
- Hot-rolled, drawn, peeled bars 30NiCrMo12, 32NiCrMo12-5, 32NiCrMo10-4, 1.6655, 1.6743
- Forgings and flat bars 30NiCrMo12, 32NiCrMo12-5, 32NiCrMo10-4, 1.6655, 1.6743
Other signs and equivalents:
30NCD12, 30 NCD 12, TALABOT 30 NCD 12, 32NiCrMo12-5, 1.6743, 32 NiCrMo 12-5, 1.6655, A 723 Grade 2, ASTM A723, K34035, S-23093A, 30NCD11, 30 NCD 11, 30NCD15, 30 NCD 15, 826M31, 826 M 31, S.153, F-127, 32NiCrMo14-5, 32 NiCrMo 14-5, 1.6746, 30NiCrMo12, 30 NiCrMo 12