42CrMo4 Alloy Steel | DIN 1.7225

42CrMo4 is alloyed heat treatable steel which is used in quenched and tempered condition with a typical tensile strength of 900 -1200 N/mm².It has high strength,good wear-resistance,high fatigue strength and good low-temperature impact toughness.Similar to AISI 4140,SCM440,only a little different in Mn,Cr,this material also has good machinability,but poor in weldability.

1.7225 forged flat bar

1.42CrMo4 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

42CrMo4/1.72250.38-0.45≤ 0.40.6-0.90.9-1.20.15-0.3≤ 0.025≤ 0.035

4.Mechanical Property

Diameter d mm≤ 1616-4040-100100-160160-250
Thickness t mm< 88-2020-6060-100 100-160
Yield Strength Mpa≥900≥750≥650≥550≥500
Tensile Strength Mpa1100-13001000-1200900-1100800-950750-900
Elongation, %≥10≥11≥12≥13≥14
Reduction of area ,%≥40≥45≥50≥50≥55


1.Preheat 42CrMo4 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 850°C;

5.Cooling as slowly as possible in still air or in sand after forged.

6.Heat Treatment

Normalizing:850℃-880℃,cool in air

Annealing:800℃-850℃,Cool in furnace,241HB Max.

Hardening:820℃-860℃,oil quench

Tempering:550°C – 650°C, cool in still air


42CrMo4 has high strength and wear-resistance,widely used in the automotive and aircraft industry, such as axle legs, axles, drive rods, crankshafts,pinions, gearwheels, linings, link plates,belt buckles, springs, saw blades, knifes and scissors.