PRODUCTION OF SINTERED PARTS OF SILICON IRON

摘要

PURPOSE:To obtain parts having a uniform surface film and high reliability in a process for production in which compaction-molded parts of silicon iron powder are annealed after sintering by providing a stage for removing the silicon dioxide on the surface of said parts after the annealing stage. CONSTITUTION:The silicon iron powder 1 is pressed by molds and molded to desired parts in a compaction molding stage 2 and the molded parts are sintered under heating in a sintering stage 3. The sintered parts are subjected to hole machining and precision machining not possible in the stage 2 in a forming stage 4 and is then subjected to annealing in an annealing stage 5 by which the prescribed magnetic characteristic is obtd. The SiO2 generated on the surfaces of the sintered parts in the sintering stage and annealing stage is removed by using a blasting method in which emery 10 is blasted at a high speed from a high pressure nozzle 11 or by using a soft cloth in an SiO2 removing stage 7. The SiO2 is thus removed without exerting working strain to the sintered parts and the uniform surface film is formed on the sintered parts in a surface finish treating stage 6 without the deterioration of the magnetic characteristics.