32CrMo12 steel is a nitriding steel which has at least 2.8Cr%,0.3%Mo as strengthening elements as per EN10250 standard.Similar with 30CrMo12,31CrMo12, it has a high tensile strength 880 – 1230 MPa after QT.32CrMo12 has high surface hardness and wear resistance after nitrided,but this material is difficult to weld and should therefore not be used in welded constructions.

32CrMo12 forged round bar

1.Supply Form & Size & Tolerance

Hot rolled round bar:Φ20-Φ120mm,Length:3000-9000mm

Hot Forged round bar:Φ130-Φ1000mm,Length:3000-10000mm

Flat bar/Blcoks:Thickness :120-800mm xWidth:120-1500mm,Length:2000-6000mm

Surface FinishBlack-Forged Black-Rolled Turned   GrindingPolishedPeeledCold Drawn
Tolerance(0,+5mm)(0,+1mm)(0,+3mm)Best h9Best h11Best H11Best H11

2.Chemical Composition

GradeCSiMnPSCrNiMo
32CrMo12/1.73610.28-0.35≤ 0.40.40-0.70≤ 0.035≤ 0.0352.8-3.3≤ 0.60.3-0.5

3.Relevant Standards

EuropeFranceUKSweden
31CrMo12/1.851530CD12722M242240

4. Mechanical Property

Thickness of ruling section T,mm≤160160-330≥330
Yield Strength Mpa≥680≥630≥490
Tensile Strength Mpa≥900≥850≥700

Elongation, %
longitudinal≥12≥13≥15
transverse≥8≥9≥11

Impact,J
longitudinal≥35≥35≥35
transverse≥20≥20≥20

5.Physical Property

  • Density: 7.8 g/cm3
  • Mean coefficient of expansion in m/m.°C:
    – between 20 °C and 100 °C:11.3 x 10-6
    – between 20 °C and 500 °C:13.6 x 10-6
  •  Critical points:
    – Ac 1: 780 °C
    – Ac 3: 835 °C
  • Modulus of elasticity :210GMpa

6.Forging

32CrMo12 steel forging temperature:900 – 1100°C ,cooling as slowly as possible in sand after forged.

7.Heat Treatment

  • Normalizing:  880 – 920°C,Cooling in air
  • Soft Annealing:650 – 700°C,Cooling in furnace,Hardness:max 248 HB
  • Hardening:890 – 940°C,water or oil quench
  • Tempering:550 – 740°C,Cooling in air
  • Nitriding: 480-570°C. Hardness after nitridng is 480-570 HV1.

8.Application

32CrMo12 is used in automotive and general mechanical engineering components which requires high hardness and wear resistance,also suitable for gear wheels, cylinders, drills, connecting rods, shafts, extruders, quides, thread gauges with relatively large-cross section.