40Cr achieves its dominance through a precisely balanced combination of properties. After quenching and tempering, it delivers tensile strength of at least 980 MPa and yield strength of at least 785 MPa, while maintaining elongation of 9% or more. This strength-toughness combination enables it to withstand cyclic loads without brittle fracture, making it suitable for components such as machine tool gears, shafts, and crankshafts.
Its chromium content of 0.80–1.10% significantly improves hardenability compared to plain carbon steels like 45#. This allows uniform hardness distribution from surface to core in medium cross-sections, ensuring reliable performance where dimensional consistency matters. Additionally, 40Cr offers moderate cold forming plasticity and reasonable machinability, facilitating economical production of complex geometries. Weldability is poor, but shafts and gears rarely require welding. The steel is also adaptable to various heat treatments—annealing, normalizing, surface hardening, and nitriding—providing engineers flexibility to tailor hardness and wear resistance for specific applications.
Just like you, 70% customers choose long-term cooperation with BBN steel not only for our good product and service quality, good reputation in the international market, but also for our experienced one-stop raw material supply and further steel processing!
