20Cr2Ni4

Product Information

Product Code: 20Cr2Ni4 is an alloy steel with high strength, good toughness, and good hardenability. After carburization, it cannot be quenched directly to reduce the residual austenite on the surface.

Standard of Execution:

Chemical Composition:

Carbon (C): 0.17～0.23

Silicon (Si): 0.17~0.37

Manganese (Mn): 0.30～0.60

Sulfur (S): Allowable residual content ≤ 0.035

Phosphorus (P): Allowable residual content ≤ 0.035

Chromium (Cr): 1.25～1.65

Nickel (Ni): 3.25～3.65

Copper (Cu): Allowable residual content ≤ 0.030

Product Application:

Used for carbonitriding and hardening structural components with high strength requirements. Commonly used in manufacturing gears for the engines and transmission systems of medium and small-sized automobiles and tractors. Also, it can replace 12CrNi3 steel to produce carbonitriding and cyaniding parts with higher core performance, such as the clamping jaws and gear hubs used in oil drilling and open-pit metallurgical mines.

Processing Technology: Hot Rolling, Cold Drawing

Features:

Heat Treatment Specifications: Quenching: first at 880°C, second at 780°C, oil cooled; tempering at 200°C, water cooled or air cooled.

Delivery Condition: Shipped in a heat treated (normalizing, annealing, or high-temperature tempering) or non-heat treated state, as specified in the contract.

The role of alloying elements in 20Cr2Ni steel:

⑴ The addition of Cr and Ni elements in 20Cr2Ni steel primarily enhances the steel's hardenability, while the Ni element aids in improving the steel's toughness.

The Si and Mn elements in the 20Cr2Ni steel primarily enhance the steel's hardenability, also contributing to the solid solution strengthening of the matrix structure and improving the tempering stability of the matrix structure.

Enhancing the corrosion resistance of the 20Cr2Ni steel by adding Cr and Ni elements.

Section 4: The 20Cr2Ni4 steel has moderate cold deformation plasticity due to its high content of C, Cr, and Ni elements, average machinability, poor weldability, strong tendency towards white spots, and significant temper brittleness.

20Cr2Ni steel, although a carburizing steel, can be heat treated and used in the quenched and tempered condition.

20Cr2Ni steel is commonly manufactured into plastic molds using cold extrusion forming methods. After carburization or carbonitriding plus quenching and low-temperature tempering treatment, the steel surface exhibits high fatigue strength, hardness, and wear resistance, while the core maintains high strength and toughness, meeting the requirements for mold use.

Mechanical properties:

Tensile Strength σb (MPa): ≥1175 (120)

Yield Strength σs (MPa): ≥1080 (110)

δ5 elongation (%): ≥10

Section Reduction Ratio ψ (%): ≥45

Impact Energy Akv (J): ≥63

Impact toughness value αkv (J/cm²): ≥78(8)

Hardness: ≤269HB

Sample Size: Raw Sample Dimensions of 15mm