Method of manufacture of a magnetic core used as an element of mémoireet core manufactured by this process

摘要

875,600. Magnetic compositions. PHILIPS ELECTRICAL INDUSTRIES Ltd. May 29, 1959 [June 3, 1958], No. 18379/59. Drawings to Specification. Class 38 (2). A ferromagnetic core suitable for a memory device and having a square hysteresis loop has a composition 30-55 mol. per cent Fe 2 O 3 , 30- 65 mol. per cent MnO, 0-15 mol. per cent CuO and 0-15 mol. per cent ZnO and is made by a method including the steps of presintering a mixture of the oxides or oxide yielding compounds between 500‹ C. and 1000‹ C., regrinding the product and moulding into a ring, sintering in an oxygen-containing atmosphere between 1150‹ C. and 1350‹ C. and cooling so that the temperature range 700 ‹ C. to room temperature is traversed as rapidly as possible. Specification 820,959 is referred to.