50CrVA has good mechanical and technological properties, high hardenability, the addition of vanadium makes the steel grain refinement, reduce superheat sensitivity, improve the strength and toughness, has a high fatigue strength, yield ratio is also higher.
However, poor weldability and low plasticity due to cold deformation. Is a more advanced spring, used as a large cross-section of high load important springs and working temperature < 300 ℃ valve springs, piston springs, safety valve springs. In general, the plate supply specifications between 1.5 ~ 10.0MM, more annealed state, more than 10 ~ 30 mm is not annealed state, the market is less spot, so often need to order futures. Steel coil for the hot-rolled state, the use of spheroidal annealing to reduce the hardness in order to create conditions for further processing. Chongqing special steel factory 50CrVA is generally annealed plate, eliminating the need for re-annealing treatment.
Medium carbon alloy spring steel, steel final heat treatment for quenching and tempering, the steel has good toughness after heat treatment, high ratio limit and strength limit, with high fatigue strength, similar to the hardenability of 65Si2MnWA, with high hardenability, low superheat sensitivity; parts use temperature at 300 ℃, its elasticity can still be maintained. The cutting performance of the steel is still good, but the plasticity is low during cold deformation and the weldability is poor.