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.

SCr440 steel

1.Chemical Composition

SCr4400.38-0.430.6-0.850.15-0.350.9-1.2≤ 0.03≤ 0.03
51400.38-0.430.7-0.90.15-0.350.7-0.9≤ 0.035≤ 0.04

2.Related Specifications


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 Annealing Diagram

SCr440 Steel Annealing Details
1.Annealing temperature:825-845℃
2.Cooling in the furnace.
3.Max hardness:201HB

SCR440-Normalizing diagram

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 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 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 StrengthElongationReduction of AreaImpact Charpy-VHardness