40CrNiMoA steel
40CrNiMoA steel is a Chinese alloy steel, it has high strength, toughness and good hardenability, and has anti-overheat stability, but it has high white point sensitivity, brittleness in quenching and poor weldability. Preheating is necessary before welding, and stress relief treatment is necessary after welding.
Properties and applications of 40CrNiMoA alloy steel
40CrNiMoA steel is used after quenching and tempering and is used to manufacture important parts that require good plasticity, high strength and large size. For example, heavy shafts in heavy machinery, steam turbine shafts with diameters greater than 250 mm, blades, transmissions, fasteners, crankshafts, gears, etc., can also be used for rotor shafts and blades operating in temperatures exceeding 400 °C.
Chemical Composition of Steel 40CrNiMo, 40CrNiMoA
| Chemical composition (%) | |||||||||
| Steel Grade | W | Yes | Mn | P | s | Cr | No | Mo | Ass |
| 40CrNiMo 40CrNiMoA |
0.37 to 0.44 | 0.17 to 0.37 | 0.50 to 0.80 | ≤ 0.020 to ≤ 0.030 | ≤ 0.010 to ≤ 0.030 | 0.60 to 0.90 | 1.25 to 1.65 | 0.15 to 0.25 | ≤ 0.25 to ≤ 0.30 |
Mechanical Properties of 40CrNiMoA Alloy Steel
- Yield strength: ≥ 835 MPa
- Tensile strength: ≥ 980 MPa
- Elongation: ≥12%
- Area reduction rate: ≥55%
- Impact absorption energy: ≥ 78 J
- Brinell hardness of material: ≤ 269 (steel rod annealed or quenched at high temperature)
- Sample size: 25mm
Heat Treatment Specification
- First quenching heating temperature: 850 °C (Quenchant – oil)
- Quenching heating temperature: 600 °C (Quenchant – water, oil)
40CrNiMoA steel equivalent to European Germany DIN EN, UK BS EN, France NF EN 10083-3, grade 39NiCrMo3
