JIS G4104 SCr440 | AISI 5140 Round bar
SCr440 | AISI 5140 Alloy steel manufacturers and suppliers, supplied in round rods,square/flat bars,rollers,shafts,blocks and forging pieces.
SCr440 alloy steel is a structural alloyed steel which contains 1.0% Cr as per JIS G4104 standard .Compared with S40C steel,it has better strength and hardenability,but may crack when welding. SCr440 is widely used in Low and moderately stressed parts for vehicles, engines and machines where hard, wear resisting surface is needed. The hardness as surface hardened can achieve to 54 HRC.
1.Chemical Composition
| Grade | C | Mn | Si | Cr | P | S |
| SCr440 | 0.38-0.43 | 0.6-0.85 | 0.15-0.35 | 0.9-1.2 | ≤ 0.03 | ≤ 0.03 |
| 5140 | 0.38-0.43 | 0.7-0.9 | 0.15-0.35 | 0.7-0.9 | ≤ 0.035 | ≤ 0.04 |
2.Related Specifications
| EN/DIN | AISI/ASTM | GB | UK |
| 41Cr4/1.7035 | 5140/2245 | 40Cr | 530M40 |
3.Supply Size
Shape:Round / Square / Flat Bars, Shafts, Rollers, Blocks.
Forged round bar
Diameter: 80-1,000mm
Length: 3,000-10,000mm
Rolled round bar
Diameter: 10-300mm
Length: 3,000-10,000mm(can be customized)
Forged square bar
Size: 150×150-600×600mm
Length: 3,000-8,000mm
Surface condition: Black/Peeled/Smooth Turned
4.Heat Treatment
SCr440 Annealing Diagram
SCr440 Steel Annealing Details
1.Annealing temperature:825-845℃
2.Cooling in the furnace.
3.Max hardness:201HB
SCr440 Normalizing Diagram
SCr440 Steel Normalizinging Details
1.Normalize temperature:850-880℃
2.Keep suitable time for the steel to be thoroughly heated.
3.Air cooling.
4.Max hardness:250HB
SCr440 Quenching Diagram
SCr440 Steel Quenching Details
1.Quench temperature:830-880℃
2.Keep suitable time for the steel to be thoroughly heated.
3.Oil Quench is recommended.
4.Tempering immediately after quenched.
SCr440 Tempering Diagram
SCr440 Steel Tempering Details
1.Temper temperature:520-620℃
2.Air cooling.
SCr440 Steel Mechanical Property With Quenching and Tempering
| Tensile Strength | Yield Strength | Elongation | Reduction of Area | Impact Charpy-V | Hardness |
| ≥932Mpa | ≥784Mpa | ≥13% | ≥45% | ≥59J | 269-331HB |