50CrMo4 Alloy Steel | DIN 1.7228 | AISI 4150

50CrMo4 is a higher carbon variation of the chromium, manganese, molybdenum 4100 series of low alloy steels.It has high strength,toughness,and high hardenability,and also has good machinability in annealed or normalized conditions.50CrMo4 can be welded using all conventional techniques. The mechanical properties of this steel can be affected if it is welded in the hardened condition. Post-weld heat treatment should be performed followed by an approved welding procedure.

Typical Application:

  •  For automotive and aircraft components with high toughness as tyres, rings, axles, bushes, shafts, steering components.
  • Statically and dynamically stressed components for vehicles, engines and machines
  • For parts of larger cross-sections. Components for driving gears, axles, rolls, rings.

50CRMO4 Forged shaft

1.50CrMo4 steel Supply Form & Size

Form of SupplySize(mm)Length(mm)
Round barΦ6-Φ1,0003,000-10,000
Square bar100x100-600x6003,000-6,000
Plate/SheetThickness :20-400
Flat bar/BlcoksThickness :120-800

2.Surface Finish&Tolerance

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

3.Chemical Composition&Related Specifications

50CrMo4/1.72280.46-0.54≤ 0.40.5-0.80.9-1.20.15-0.3≤ 0.025≤ 0.035

4.50CrMo4 Mechanical Property

Diameter d mm≤ 1616-4040-100100-160160-250
Thickness t mm< 88-2020-6060-100 100-160
Yield Strength Mpa≥900≥780≥700≥650≥550
Tensile Strength Mpa1100-13001000-1200900-1100850-1000800-950
Elongation, %≥9≥10≥12≥13≥13
Reduction of area ,%≥40≥45≥50≥50≥50

5. Forging for 50CrMo4

  1. Preheat 50CrMo4 engineering steel uniformly and slowly;
  2. Increase the forging temperature up to 1150-1200°C;
  3. hold suitable time for the steel to be thoroughly heated before forge;
  4. Reheat steel  when temperature  below 950°C;
  5. Cooling as slowly as possible in sand after forged.

6.Heat Treatment

Soft Annealing

  • Heat the steel  to 680-720°C uniformly and slowly
  • hold suitable time for the steel to be thoroughly heated
  • cool slowly in furnace
  • maximum Brinell hardness of 248.

Normalizing: 840-860°C,cool in air

Hardening:820 – 860°C,oil quench

Tempering:540-680°C,cool in air

7.Hardness after heat treatment

  • Annealed at 815°C: 197 HB
  • Normalized at 870°C: 321 HB
  • Oil quenched, fine grained, tempered at 205°C: 530 HB
  • Oil quenched, fine grained, tempered at 315°C: 495 HB
  • Oil quenched, fine grained, tempered at 425°C: 440 HB
  • Oil quenched, fine grained, tempered at 540°C: 370 HB
  • Oil quenched, fine grained, tempered at 650°C: 290 HB