Effect of annealing temperature on the microstructure and magnetic properties of heat-resistant oriented silicon steel

Effect of annealing temperature on the microstructure and magnetic properties of heat-resistant oriented silicon steel

Silicon steel can be divided into non-heat-resistant oriented silicon steel and heat-resistant oriented silicon steel according to heat resistance. Non-heat-resistant type
Directional silicon steel is mainly used to prepare traditional laminated core transformers, and the core does not require high-temperature annealing treatment, while heat-resistant oriented silicon steel is mainly used to prepare three-dimensional wound core transformers.

The researchers once selected heat-resistant oriented silicon steel strips from two different process technologies, the toothed roller groove method and the laser irradiation method, for annealing heat treatment, carried out a comparative study of heat resistance experiments, and analyzed the performance of the two strips under different annealing temperatures,changes in material microstructure and magnetic properties.
The technical principles of the two types of heat-resistant oriented silicon steel are obviously different. The toothed roller groove method forms small grain structures and "gaps" on the surface of the strip, while the laser irradiation method forms grooves on the surface of the strip. The influence of the toothed roller groove method on the structure of the strip in the thickness direction is the formation of score affected areas and twin structures, while the laser irradiation method has no obvious effect on the structure of the strip in the thickness direction.

The heat resistance temperature of silicon steel oriented by laser irradiation method is about 850 ℃, and the heat resistance temperature of silicon steel oriented by toothed roller groove method is about 800 ℃. The former has better heat resistance. As the annealing temperature increases, the losses of the two strips gradually increase, and the loss of the former The increase in loss may be related to the change in Goss grain orientation near the trench, and the latter It is mainly caused by the reduction in the Goss grain orientation difference between the scored area and both sides.