Abstract: Based on research of 0.27 mm gauge high magnetic induction grain oriented silicon steel, the influence of the laser scribing power, scribing frequency, scribing speed and scribing spacing on the core loss reduction and magnetic domain structure of grain oriented silicon steel were studied in this paper. It was showed that there were differences in the morphology and domain structure of the scribing lines in different processes. The scribing lines showed light morphology and the magnetic domains were inhomogeneous and scattered at low power, high frequency and high speed.The results showed that the maximum iron loss reducing rate reached 9.47 % under the parameters of 30 % scribing power, 50 kHz scribing frequency, 500 mm/s scribing speed and 5 mm scribing space. Besides that, under the interaction of laser scribing parameters, the iron loss reducing rate increased significantly with the increase of laser energy density, and the damage to the stress coating of grain oriented silicon steel aggravated with the increasing of energy density, which was not conducive to the magnetic domain refinement and the increase of iron loss reduction.

Key words: grain oriented silicon steel, laser scribing, domain refinement, core loss reducing rate