Interlocking Performances on Non-Oriented Electrical Steels

Interlocking performance as fastened strength and magnetic deterioration by interlocking were investigated. The thickness of a surface insulation coating affected the interlocking fastened strength. Sheets with a thin coating resulted in a better interlocking performance than those with a thick coating due to the lubricating effect by resin as coating materials. Sheet gauge affected the interlocking fastened strength. The fastened strength of thin gauge sheet was less than that of a thick one, because of the reduction of the sticking area of interlocking protuberances. The protuberance shapes affected the fastening strength. The rectangular types are stronger than the circular ones, due to the ‘hooked by corners’ effect. Magnetic deteriorations by interlocking was caused by the core loss increased by the obstruction of magnetic flux flows and eddy current loss through the laminations. The core loss increased by the eddy current loss through the laminations was 78% of all deterioration by interlocking.