24 July 2021 Structural Steel Bar
42CrMo4 Structural Steel Bar
42CrMo4 steel is an improved variety of American AISI standard 4140 steel. The steel has good machinability, easy polishing, biting and electroplating. It is suitable for manufacturing mechanical parts with high strength, high hardenability, good toughness, small deformation during quenching and high creep strength and endurance strength at high temperature. It can be used to manufacture forgings with higher strength and larger quenching and tempering section than 35CrMo steel, such as large gears for locomotive traction, supercharger transmission gears, rear axles, connecting rods and spring clamps with great load, and 42CrMo4 can also be used for drill pipe joints and fishing tools in deep oil wells below 2000m.
Chemical Composition of 42CrMo4:
- Carbon C: 0.38-0.45
- Silicon Si: 0.17-0.37
- Manganese Mn: 0.50-0.80
- Sulfur S: <0.035
- Phosphorus P: < 0.035
- Chromium Cr: 0.90-1.20
- Nickel Ni: Allowable Residual Content < 0.030
- Copper Co: Allowable Residual Content < 0.030
- Molybdenum Mo: 0.15-0.25
42CrMo4 Equivalent World Steel Grade:
- China GB 42CrMo,
- Russia OCT 38XM,
- USA AISI 4140/4142,
- UK BS 708M40/708A42/709M40,
- France NF 40CD4/42CD4,
- Germany DIN 41CrMo4/42CrMo4,
- Japan JIS SCM4
Mechanical properties of 42CrMo4:
- Density: 7.85x103kg/m3
- Tensile strength_b (MPa): > 1080 (110)
- Yield strength_s (MPa): > 930 (95)
- Section shrinkage(%): > 45
- Impact energy Akv (J): > 63
- Impact toughness value alpha kV (J/cm²): > 78 (8)
- Sample size: Sample blank size 25 mm
Heat treatment specification and metallographic structure:
Heat treatment specifications: quenching 850 C, oil-cooled; tempering 560 C, water-cooled, oil-cooled.
Metallographic structure: tempered sorbite.
Delivery status of 42CrMo4:
Delivery under heat treatment (normalizing, annealing or high temperature tempering) or non-heat treatment. Delivery status shall be specified in the contract.
Specification for softening annealing of 42CrMo4
- The annealing temperature is 680 ~700 C, the furnace is slowly cooled, and the hardness is less than 217HBW.
- Specification for Quenching and Tempering of 42CrMo4
- Quenching temperature 830 ~860 C, oil-cooled or 180 220 C salt bath cooling, hardness 52HRC, strength 1780 MPa.
- Tempering temperature 100 C/200 C/300 C/400 C/500 C/600 C, hardness 50HRC/49HRC/46HRC/42HRC/36HRC/28HRC
5. MTC of 42CrMo4:
6. Our 42CrMo4 in stock photos:
42CrMo4 alloy steel process now is very mature and China factory could produce it in competitive price, in good quality, we store thousands tons of 42CrMo4 material both in hot-rolled, cold-rolled status, in shape of square bar, round bar and plate. You can check our in stock photos.
Do you wish to know the difference 42CrMo4 vs 42CrMo ?
Based on our history order and experience, we summarize the difference between 42CrMo4 and 42CrMo from chemical composition, mechanical performance, application, if you wish to know the detailed difference please click the URL above.