| 摘要 |
PURPOSE:To add micro-plastic strains to an magnetic steel sheet noncontactually without giving any shape change to the steel plate surface and improve iron loss value by linearly irradiating laser light along the rolling direction of the unidirectional magnetic steel sheet. CONSTITUTION:Laser light of 0.5-5J/cm<2> irradiation energy is linearly irradiated to a unidirectional magnetic steel sheet used for cores of transformers etc. in the rolling direction (L direction) or in the direction of an angle to the L direction within 45 deg.. The irradiation of the laser light is performed from the perpendicular direction of the steel plate surface to the L direction in such a manner that the irradiation width becomes 0.01-1mm.. In the irradiated steel plate parts, the new magnetic domains are produced in the form that they extend in the C direction without giving any deformation to the steel plate by impulse wave effect, thus the iron loss value in the C direction normal to the rolling direction is improved and this material has superior performance as a material for large-sized rotating machines or a material for the EI cores of transformers. |
