24 July 2021 Structural Steel Bar
SCR440 Structural Steel Bar
SCR440 is an alloy structural steel, is the most commonly used alloy structural steel, tensile strength, yield strength and hardenability are higher than the 40 steel. 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.
For more important quenched parts, such as parts under alternating load, medium-speed and medium-load parts. After surface hardening can be made for high load and wear resistance, without great impact on the parts, such as gears, sleeves, shafts, crankshafts, pins.
Chemical Composition:
| C(％) | Si(％) | Mn(％) | P(％) | S(％) | Cr(％) | Ni(％) | Cu(％) |
|---|---|---|---|---|---|---|---|
| 0.38～0.43 | 0.15 ~ 0.35 | 0.60 ~ 0.90 | ≤0.030 | ≤0.030 | 0.90～1.20 | ≤0.25 | ≤0.030 |
Mechanical Propoerties:
| Yield Strength Rp0.2(MPa) | Tensile Strength Rm(MPa) | Elongation δ5 (%): | Reduction of area ψ (%): | Impact energy Akv (J): | Impact toughness value αkv (J/cm2) | Hardness |
|---|---|---|---|---|---|---|
| ≥ 785(80) | ≥ 985(100) | ≥ 9 | ≥ 45 | ≥ 47 | ≥ 59(6) | ≥ 207 HB |
Heat treatment specifications:
- quenching 850 ℃, oil cooling;
- tempering 520 ℃, water-cooled, oil-cooled.
Delivery status:
Heat treatment (normalizing, annealing or tempering) or non-heat treatment delivery, delivery status should be specified in the contract.