Secondary Recrystallization Behaviors of Grain-Oriented 6.5 wt% Silicon Steel Sheets Produced by Rolling and Nitriding Processes

Abstract

By rolling and nitriding processes, 0.23-to 0.3-mm-thick grain-oriented 6.5 wt% silicon steel sheets were produced. The core losses of grain-oriented 6.5 wt% silicon steel at frequencies ranging from 400 Hz to 20 kHz were lower than that of the grain-oriented 3 wt% silicon steel with the same thickness by 16.6-35.8%. The secondary recrystallization behavior was investigated by scanning electron microscopy, energy-dispersive spectroscopy, and electron backscattered diffraction. The results show that the secondary recrystallization in high-silicon steel sheets develops more completely as the nitrogen content increases after nitriding, secondary recrystallized grain sizes become larger, and the sharpness of Goss texture increases. Because more 110 f g 116 h i grains in the subsurface and the central layer of the sheets have a lot of 20°-45°high-energy boundaries in addition to Goss grains, 110 f g 116 h i can be the main component through selective growth during secondary recrystallization when the inhibitor quantity is not enough and inhibitor intensity is weaker. The increases in nitrogen content can increase the inhibitor intensity and hinder abnormal growth of a mount of 110 f g 116 h i grains and therefore enhance the sharpness of Goss texture.

Evolution of Microstructure and Texture in Grain-Oriented 6.5% Si Steel Processed by Rolling with Intrinsic Inhibitors and Additional Inhibitors

“…These reports have involved an analysis and comparison of the magnetic properties of this steel with non-oriented high-silicon steel, as well as non-oriented and grain-oriented silicon steel containing 3% Si with the same sheet thickness. Our laboratory study also successfully prepared grain-oriented high-silicon steel by adding inhibitors in the early stage [18]. Nonetheless, the process stability is insufficient, and there is still significant room for improvement in the magnetic properties.…”

Promoted diffusion mechanism of Fe2.7wt.%Si-Fe10wt.%Si couples under magnetic field by atomic-scale observations

“…Among the family of silicon steels, the 6.5 wt. % high silicon steel exhibits excellent comprehensive properties such as low magnetocrystalline anisotropy, near zero magnetostriction, low core lose and so on 2–4 . However, the 6.5 wt.% Si steels are difficult to fabricate through conventional rolling process due to the appearance of B 2 (FeSi) and D0 3 (Fe 3 Si) ordered phases which result in embrittlement 5 .…”