MOTOR CORE WITH SMALL IRON LOSS DETERIORATION UNDER COMPRESSION STRESS

摘要

PROBLEM TO BE SOLVED: To provide a motor core that is small in deterioration of a high frequency iron loss characteristic even in the presence of compression stress.SOLUTION: In a motor core, electromagnetic steel plates having a component composition preferably containing 4 mass% or less of Si, 3 mass% or less of Al, 0.05-3 mass% of Mn, 0.005 mass% or less of S, 0.005 mass% or less of N, and 0.010 mass% or less of O, and on which a glassy insulation coat is applied, are laminated, and compression stress of 10 MPa or more is applied in a circumferential direction. Laser irradiation is performed onto a back yoke part of the electromagnetic steel plate constituting the motor core at an interval of 0.3-5 mm.