50CrVA (GB/T 1222) is a chromium-vanadium alloy round steel engineered for high-stress springs, with properties that outperform standard spring steels:
Tensile strength: 1275–1470 MPa after quenching (850°C) and tempering (410°C), enabling it to handle heavy loads in valve springs and suspension coils.
Yield strength: ≥1128 MPa, ensuring minimal permanent deformation even after 10⁶ cycles of deflection.
Hardness: 40–45 HRC, balancing elasticity and resistance to set (permanent deformation under sustained load).
Fatigue limit: ≥550 MPa, critical for engine valve springs that operate at 10,000+ cycles per minute.
Its chemistry (0.46–0.54% C, 0.80–1.10% Cr, 0.10–0.20% V) promotes fine grain structure and carbide precipitation, enhancing fatigue resistance. 50CrVA is equivalent to ASTM 6150 (USA) and DIN 1.8159 (Germany), used in racing engines and industrial machinery requiring reliable spring performance.