Enhanced corrosion resistance of hard steel wires produced by electrochemical cold drawing

The corrosion resistance of AISI 1070 and FeSi6.5 steel wires produced by conventional cold drawing (CD) and electrochemical cold drawing (ECD) technologies were compared. The corrosion rate of steel wire FeSi6.5, obtained by the method of ECD, was lower than that of the wire obtained by the method of CD, while this difference for steel AISI 1070 was not pronounced. The main reason can be explained by the fact that the ECD technology has significantly reduced surface defects and residual stress in steel wires FeSi6.5, and, thus, increased the corrosion resistance. However, for steel wire 1070, the initial smooth surface and the microstructure of severe deformation were the dominant factors affecting the corrosion rate, and since the proportion of the positive effect that improves the corrosion resistance was reduced, there was therefore no obvious difference between the two technologies. Surface condition and internal stress were the main factors affecting the corrosion rate. ECD demonstrated an important effect on the promotion of plastic deformation and improvement of surface quality, and, therefore, was a promising technology for improving the formability of hard steels.