Role of Nb-bearing inhibitors in grain-oriented silicon steel manufactured by low-temperature slab reheating process

ABSTRACT

A comparative study of precipitates, microstructure, texture and magnetic properties between conventional and Nb-bearing grain oriented silicon steel was carried out. The results show that fine and dispersed Nb-bearing particles are formed in Nb-bearing steel and show stronger pinning force during the whole heat treatment process, which makes a significant effect on the microstructure and texture evolution during the preparation process. Compared to conventional grain oriented silicon steel, Nb-bearing steel exhibits finer microstructure and possesses more Goss grains in hot-rolled band and normalized band. In primary recrystallized band, fine and uniform microstructure is presented in Nb-bearing steel, meanwhile, it is also characterized by strong γ-fiber and {114}<481> texture. After final annealing, Nb-bearing steel shows better magnetic properties, B₈₀₀=1.87 T and P_1.7/50=1.25 W kg^-1. In summary, niobium can be used as an effective inhibitor formation element to produce high quality Nb-bearing grain oriented silicon steel manufactured by low-temperature slab reheating process.

KEYWORDS:

• Nb-bearing
• grain oriented silicon steel
• heat treatment
• low-temperature slab reheating process
• precipitates
• microstructure
• texture
• magnetic properties

Acknowledgements

The authors of this paper thank the National Natural Science Foundation of China. We would like to thank Dr. Zhen Wang at the Analytical & Testing Center of Wuhan University of Science and Technology for the help on EBSD analysis.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the National Natural Science Foundation of China [Grant Number 51674180].