24 July 2021 Structural Steel Bar
CF53 Structural Steel Bar
CF53 structural steel is an imitation steel for surface hardening imported from Germany DIN Standard. Due to its low hardenability, it has good mechanical properties, especially multi-impact properties and contact fatigue properties. The hardenability curve of CF53 steel was measured by the end quenching method, and according to the hardenability curve, the hardness distribution curve on the bar section, the ideal critical hardenable diameter and the actual critical hardenable diameter, and the cross-sectional hardness distribution curve were obtained. Then, samples of different diameters were used to determine the critical hardenability diameter, and the structure changes were observed by metallographic method to analyze the reasons for the low hardenability.
Chemical Composition:
| C(％) | Si(％) | Mn(％) | P(％) | S(％) | Cr(％) | Ni(％) | Cu(％) |
|---|---|---|---|---|---|---|---|
| 0.50～0.70 | 0.15 ~ 0.35 | 0.50 ~ 0.80 | ≤0.025 | ≤0.035 | - | - | - |
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 |
|---|---|---|---|---|---|---|
| ≥ 352 | ≥ 374 | ≥ 12 | ≥ 33 | ≥ 14 | ≥ 21 | ≥ 201 HB |
Applications:
Steels for superficial hardening: Piston bolts, chain bolts, gear shafts, gear wheels, worms and camshafts.
Physical properties:
(avarage values) at ambient temperature
Modulus of elasticity [103 x N/mm2]: 210
Density [g/cm3]: 7.84
Soft Annealing：
Heat to 650-700oC, cool slowly. This will produce a maximum Brinell hardness of 223.
Normalizing:
830-860oC.
Stress Relieving:
Stress relieving to remove machining stresses should be carried out by heating to 120-200oC, holding for one hour at heat, followed by air cooling. This operation is performed to reduce distortion during heat treatment.
Hardening:
Harden from a temperature of 810-845oC followed by oil or water quenching. Hardness after quenching is 57-62 HRC.
Tempering:
Tempering temperature: 550-660oC.
Equivalent Grade:
China GB standard steel 50#;
Japan's JIS standard steel S50C / S53C;
German DIN standard material steel number 1.1213;
German DIN standard steel CF53;
British BS standard steel No. 060A52;
French AFNOR standard steel XC48TS;
French NF standard steel C50;
Italy UNI standard steel C53;
Belgium NBN standard steel C53;
Swedish SS standard steel No. 1674;
Spanish standard steel F.112;
US AISI / SAE standard steel 1050;
International Organization for Standardization ISO standard steel C50E4 above can be replaced with each other