Study on primary recrystallization behavior of Fe-3%Si-Cu alloy with copper-rich precipitates as main inhibitor

In order to break through the bottleneck of high energy consumption in the production of traditional grain-oriented electrical steel, this paper creatively proposes a new composition system of grain-oriented electrical steel with Cu-rich precipitates as main inhibitor. In this research, the microstructure, texture, precipitates and decarburization effect of the pri-mary recrystallization samples are analyzed in the process of decarburization annealing treatment at 850-900 degrees C for different time. The results show that with Cu-rich precipitates as main inhibitor, the annealing temperature has a great influence on the decarburization effect. The decarburization effect at 850 degrees C is the best, followed by 875 and 900 degrees C. The residual carbon content decreases first and then tends to level off with the increasing decarburization time. The optimal process is decarburization annealing at 850 degrees C for 6 min, in which case the carbon content can be reduced to less than 40 ppm, and the average grain diameter is about 16.1 mm. The primary recrystallized textures mainly include {111}< 112 >, {111}< 110 >, {114}< 418 >, {112}< 110 > and a small number of Goss-oriented grains. In the decarburized annealed matrix, the Cu-rich precipitates are about 10-50 nm in size, with a distribution density of about 5.06 x 109/cm2, and thus can be used as an effective inhibitor for grain-oriented electrical steel. When the sample is annealed at a high temperature, above 1000 degrees C, the large-scale secondary recrystallized macrostructure of the steel is formed, more importantly, there is no need for a long purification heat treatment at 1200 degrees C. (c) 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

This paper proposes a new composition system of grain-oriented electrical steel with Cu-rich precipitates as the main inhibitor to overcome the bottleneck of high energy consumption in traditional grain-oriented electrical steel production. The research analyzes the microstructure, texture, precipitates, and decarburization effect of primary recrystallization samples during decarburization annealing treatment at different temperatures and times. The results show that annealing temperature significantly affects the decarburization effect, with the best effect at 850 degrees C. The optimal process is decarburization annealing at 850 degrees C for 6 minutes, reducing the carbon content to less than 40 ppm and achieving a good inhibiting effect with Cu-rich precipitates.