Effect of Vanadium on the Microstructure and Mechanical Properties of 2100 MPa Ultra-High Strength High Plasticity Spring Steel Processed by a Novel Online Rapid-Induction Heat Treatment

Abstract Advanced automotive industries generate large demand for the next generation of high strength and toughness spring steels. Vanadium-containing 55SiCrV steels subjected to rapid-induction heating treatment can fulfil such requirements. However, effect vanadium microalloying under online heat treatments is rarely reported. A comparative study microstructure tensile properties 55SiCr steel wires a novel rapid induction has been demonstrated herein. It found that wire decreases with decrease in speed heating, plasticity increases. Whereas, increases retained plasticity, which attributed strengthening dislocations. Through optimized heating/cooling thermal cycles intermediate-temperature tempering treatment, approaches 2106 MPa total elongation 9.7%. Compared steel, addition V changes toughening mechanisms via grain refinement enhancement hardenability resistance. The finely dispersed V-containing secondary phases are matrix, indicates precipitation stemming from not dominant factor process. proposed provides promising pathway mechanical property improvement steel. Graphical