40CrNi2Si2MoVA

18Cr2Ni4WA is a high-strength, medium-alloy carburizing steel. To prevent excessive carbide and austenite content, carburize at high temperatures of 900-920°C, temper at 600-650°C, undergo cryogenic treatment, and oil quenching, which yields a hardness of around 48. To achieve HRC58-63, surface carburization is necessary.

18Cr2Ni4WA steel is a commonly used alloy carburizing steel with high strength and toughness, good hardenability, and can also be used for quenching and tempering without carburization. It is generally used for critical components with large cross-sections, high loads, good toughness, and low notch sensitivity.

For critical components operating under heavy load conditions, such as gears and crankshafts in high-speed diesel engines, heavy-duty trucks, and aircraft engines, the 18Cr2Ni4WA alloy, which contains a higher percentage of alloying elements, is often used.

Material Name: Alloy Structural Steel

Grade: 18Cr2Ni4WA

Standard: GB/T 3077-1988

18Cr2Ni4WA is a high-strength medium alloy carburizing steel. To prevent excessive carbonitride and austenite content, carburize at 900-920°C after carburizing, temper at 600-650°C, undergo cryogenic treatment, and oil quench, resulting in a hardness of around 48. To achieve HRC 58-63, surface carburizing is necessary.

18Cr2Ni4WA steel is a commonly used alloy carburizing steel with high strength and toughness, good hardenability, and can also be used for tempering without carburization. It is generally used for important components with large cross-sections, high loads, good toughness, and low notch sensitivity.

Chemical Composition

Carbon (C): 0.13～0.19

Silicon (Si): 0.17～0.37

Manganese (Mn): 0.30～0.60

Sulfur (S): Allowable residual content ≤ 0.025

Phosphorus (P): Allowable residual content ≤ 0.025

Chrome (Cr): 1.35～1.65

Nickel (Ni): 4.00～4.50

Copper (Cu): Allowable residual content ≤ 0.025

Tungsten (W): 0.80～1.20

Mechanical Properties

Tensile Strength σb (MPa): ≥1180

18Cr2Ni4WA Round Steel

Yield Strength σs (MPa): ≥835

Tensile elongation δ5 (%): ≥10

Section reduction rate ψ (%): ≥45

Impact Energy Akv (J): ≥78

Impact toughness value αkv (J/cm²): ≥98(10)

Hardness: ≤269HB

Sample Size: Sample blank size is 15mm

Heat Treatment Specifications and Microstructure

Heat Treatment Specifications: Quenching: first at 950°C, second at 850°C, air cooled; tempering at 200°C, water or air cooled.

Shipment Status

Delivered in heat-treated (normalizing, annealing, or high-temperature tempering) or non-heat treated condition, as specified in the contract.