50CrV chemical composition and mechanical properties
Chemical composition:
Carbon C: 0.46 to 0.54 Hong Kong Chang steel 50CRV spring steel bars
Silicon Si: 0.17 ~ 0.37
Manganese Mn: 0.50 ~ 0.80
Sulfur S: ≤ 0.030
Phosphorus P: ≤ 0.030
Chromium Cr: 0.80 ~ 1.10
Nickel Ni: ≤ 0.35
Copper Cu: ≤ 0.25
Vanadium V: 0.10 ~ 0.20

Mechanical properties:
(Note: the material cross-sectional area in different circumstances different mechanical properties)
Tensile strength σb (MPa): ≥ 1274 (130)
Yield strength σs (MPa): ≥ 1127 (115)
Elongation δ5 (%): ≥ 10
Reduction of area ψ (%): ≥ 40
Hardness: hot, ≤ 321HB; Cold Drawn + heat treatment, ≤ 321HB heat treatment and microstructure specifications: Heat treatment specifications: quenching 850 ° C ± 20 ° C, oil cooling; tempering 500 ° C ± 50 ° C (special needs, ± 30 ℃ ).