High-performance reality of 55SiCrV spring steel processed by the rapid-induction heat treatment

Abstract

Heat treatment methodology is vital to achieve high performance of advanced spring steel. The present study has investigated the microstructure and mechanical properties of the 55SiCrV spring steel processed by a novel online rapid-induction heat treatment. The results showed that rapid heating refines the prior austenite grain size of the 55SiCrV spring steel, and the vanadium mainly exists as the solid solution in the matrix instead of the dispersive precipitation of the V-containing secondary phase under the rapid induction heat treatment condition. An optimal combination of mechanical properties simultaneously with ultrahigh strength and high plasticity was obtained and the properties of the steel are mainly enhanced by the hardenability and tempering resistance of solute V in the material.

Heat Treatment Process, Microstructure, and Mechanical Properties of Spring Steel with Ultra-High Strength and Toughness

“…In Equation (2), αγ is the average lattice parameter of retained austenite. Using Equation (6), αγ is calculated through the diffraction angle and the corresponding [hkl] diffraction [30]. Λ is the diffraction wavelength.…”

“…It is well known that the main methods for developing spring steel with high strength and toughness include adjusting its alloy composition [2], microalloying [3][4][5], and optimizing heat treatment processes [6]. Over the years, the heat treatment process has evolved from traditional quenching and tempering (Q−T) to quenching and partitioning (Q−P); on this basis, various heat treatment methods based on Q−P technology have been developed to achieve better mechanical properties for spring steel [7].…”