METHOD FOR ANNEALING IRON CORE MATERIAL FOR ELECTRIC APPARATUS

摘要

PURPOSE:To manufacture an iron core material having superior magnetic characteristics by annealing a blanked iron core material for an electric apparatus by induction heating while controlling electric power supplied per unit weight of the material to a specified value to carry out strain relieving annealing with high thermal efficiency in a short time. CONSTITUTION:A blanked iron core material for a motor, a transformer or the like is annealed to relieve strain produced during blanking, thereby reducing the iron loss and improving the magnetic characteristics. At this time, heating is carried out by induction heating, and electric power is supplied by 0.5-3kW per 1kg material. The iron core material is annealed by holding at 750 deg.C for >=2hr under heating to reduce the iron loss due to strain produced during blanking, and an iron core material having superior magnetic characteristics is obtd. by the annealing with high power efficiency.