The significant impact of the crystallization of cementite in high carbon steel wire on its torsional performance

This article investigates the mechanism behind the significant differences in torsional properties of high carbon steel wire rods under two different drawing conditions when subjected to the same hot-dip galvanizing treatment. In our experiment, two types of drawn wires were annealed at 200–500 °C. X-ray diffraction, transmission electron microscopy, and high-resolution transmission electron microscopy were used to comprehensively analyze the changes in ferrite lattice parameters, the dissolution of cementite, and the crystallization process under the two drawing conditions. The finite element method is used to simulate the strain in different drawing processes. The experimental results indicate that the wire subjected to less equivalent plastic strain shows good torsion ability during wire drawing, which is due to the slow crystallization process of cementite dissolved in ferrite during hot dip galvanization.