MEJORAS EN LA FABRICACIÓN DE POLVO MAGNÉTICO

摘要

587,138. Granulating metals ; alloys. STANDARD TELEPHONES & CABLES, Ltd., WESTON, W. K., BUCKLEY, S. E., and JOHNSTON, T. Oct. 3, 1944, No. 18896. [Classes 82 (i) and 82 (ii)] [Also in Groups XXII and XXXV] A core having low hysteresis and eddy current losses is made from a magnetic material reduced to a finely divided form by being melted and poured from a ladle 1 into water in a tank 2, the stream of molten liquid being scattered by a water jet from a nozzle 5 to solidify it into comparatively large fragments which collect in a tray 4. The fragments are dried, crushed in a hammer mill and rolled in a ball mill to a fine dust. Alloys used may be as follows, nickel 81 per cent., iron 17 per cent., molybdenum 2 per cent., and nickel 80 per cent, molybdenum 12.5 per cent., iron 7.5 per cent., but the use of silicon alloys is disclaimed. An embrittling agent such as a small quantity of iron sulphide may be added. Before mechanical pulverization, reheating and cooling may be carried out as described in Specification 564,651 and the dust may be formed into a core with insulating and bonding material as described in Specification 578,250.