The effect of temper rolling and final annealing on microstructure, texture and magnetic properties of non-oriented electrical steels

Abstract

In this paper, the effect of temper rolling and final annealing on microstructure, texture and magnetic properties of a 0.6 wt% Si non-oriented electrical steel, with 5.7% temper rolling reduction, were investigated via EBSD and XRD three-dimensional orientation distribution function (ODF) analysis. The results indicate that final annealing plays an essential role in improving the magnetic properties of non-oriented electrical steels. The core loss decreases with the increasing annealing time, reaches the lowest value at 10 min, and then tends to be stable. The magnetic induction quickly increased with prolonged annealing time, reached the highest value, then decreased slightly to a lower value after 15 min. The peak permeability increased rapidly with the increasing annealing time, reached the highest value after 3 min, and became stable after 10 min. The grains abnormally develop from the sample surface to the inner layer derived from gradient strain. Before and after temper rolling, the texture of the material is mainly dominated by {111}<112>. As annealing time increases, the intensity of {111}<112> decreases, emerging the weak Goss ({110}<001>) and other orientations. Finally, there are without preferred orientations when time exceeds 10 min.