Improvements in or relating to magnetically soft ferrites having rectangular hysteresis loops

摘要

834,230. Magnetic compositions. STEATIT MAGNESIA A.G. March 12, 1956 [March 11, 1955], No. 7726/56. Drawings to Specification. Class 38 (2). A manganese magnesium lead ferrite suitable for magnetic storage cores, having a rectangular hysteresis loop and low coercivity is made by grinding with water 35 mol. per cent Fe 2 O 3 , 35 mol. per cent MnO and 30 mol. per cent MgO, presintering at 850-1200‹ C., adding up to 10% by weight of PbFe 2 O 4 and sintering at 1350‹ C. at 2 hours. In alternative methods of manufacture a compound of lead, such as lead oxide, is added to the starting mixture of oxides.