Executive Standard: JIS G4053-2003
● Features and application:
Is the most common alloy structural steel, tensile strength, yield strength and hardenability of steel is higher than 40, but welding is limited, there is a tendency to form cracks. Quenching for the more important parts, such as alternating the parts work load, medium speed and medium load of parts. After surface hardening and wear resistance can be used for high load and without a great impact on the parts such as gears, sleeves, shafts, crankshafts, pins.
● Chemical Composition:
Carbon C: 0.38 ~ 0.43
Si Si: 0.15 ~ 0.35
Manganese Mn: 0.60 ~ 0.90
Sulfur S: to allow the residual content ≤ 0.030
Phosphorus P: to allow the residual content ≤ 0.030
Chromium Cr: 0.90 ~ 1.20
Ni: to allow the residual content of ≤ 0.25
Copper Cu: to allow the residual content ≤ 0.030
● Mechanical Properties:
Tensile strength σb (MPa): ≥ 980 (100)
Yield strength σs (MPa): ≥ 785 (80)
Elongation δ5 (%): ≥ 9
Reduction of area ψ (%): ≥ 45
Impact energy Akv (J): ≥ 47
Impact toughness αkv (J/cm2): ≥ 59 (6)
Hardness: ≤ 207HB
Sample size: Sample size is 25mm rough
● Heat treatment and microstructure specifications:
Standard heat treatment: quenching 850 ℃, oil cooling; tempering 520 ℃, water-cooled, oil-cooling.
● Delivery status: to heat treatment (normalizing, annealing, or tempering) or heat treatment delivery, delivery status should be indicated in the contract.
