Magnetic materials and their methods of manufacture

Claim 1

A METHOD OF MANUFACTURING MAGNETIC CORES OF A FERRITE MATERIAL HAVING A HIGH PERMEABILITY AND LOW LOSSES AT HIGH FREQUENCY WHICH COMPRISES FORMING AN INITIAL HOMOGENOUS MIXTURE OF FINE POWDERS OF PURE IRON SESQUIOXIDE, MANGENESE OXIDE, AND ZINC OXIDE, THE RESPECTIVE MOLECULAR PERCENTAGES IN THIS MIXTURE RANGING RESPECTIVELY FROM 50 TO 55.6% FOR THE IRON SESQUIXIDE, AND FROM 24 TO 39% FOR THE MANGENESE OXIDE, THE LATTER VALUE BEING DEFINED WITH RESPECT TO THE NUMBER OF ATOMS OF MANGENESE, THE REMAINDER CONSISTING OF ZINC OXIDE, SAID MIXTURE OF OXIDES CONTAINING AT MOST 0.5% BY WEIGHT OF EACH OF THE TWO METALS CONSTITUTED BY BARIUM AND STRONIUM COMPRESSING SAID MASS UNDER A PRESSURE RANGING FROM, 3 TO 10 TONS PER SQ. CM. TO GIVE IT THE DESIRED CORE FORM, SUBJECTING THE COMPRESSED MASS TO A THERMAL TREATMENT WHICH COMPRISES HEATING IT FROM 2 TO 4 HOURS AT A TEMPERATURE RANGING FROM 1170* TO 1280*C. IN AN ATMOSPHERE ESSENTIALLY CONSTITUTED BY A CHEMICALLY INERT GAS, BUT CONTAINING A SMALL AMOUNT OF OXYGEN, ADJUSTING THE PERCENTAGE OF OXYGEN IN SAID ATMOSPHERE AT LEAST DURING THE LAST FIFTEEN MINUTES OF THE THERMAL TREATMENT AND DURING COOLING FROM 0.01 TO 1.2 IN VOLUME, THIS ATMOSPHERE BEING CHOSEN IN SUCH MANNER AND THE HEATING AND COOLING OPERATIONS BEING SO CONDUCTED AS TO OBTAIN A FINAL PRODUCT IN WHICH A PORTION OF THE IRON SESQUIOXIDE INITIALLY PRESENT IN THE MIXTURE HAS BEEN CHANGED INTO FEO, THIS PORTION RANGING FROM 0.2 TO 4.7 PERCENT BY WEIGHT.

Claim 2

A METHOD OF MANUFACTURING MAGNETIC CORES OF A FERRITE MATERIAL HAVING A HIGH PERMEABILITY AND LOW LOSSES AT HIGH FREQUENCY WHICH COMPRISES FORMING AN INITIAL HOMOGENOUS MIXTURE OF FINE POWDERS OF PURE IRON SESQUIOXIDE, MANGENESE OXIDE, AND ZINC OXIDE, THE RESPECTIVE MOLECULAR PERCENTAGES IN THIS MIXTURE RANGING RESPECTIVELY FROM 50 TO 55.6% FOR THE IRON SESQUIXIDE, AND FROM 24 TO 39% FOR THE MANGENESE OXIDE, THE LATTER VALUE BEING DEFINED WITH RESPECT TO THE NUMBER OF ATOMS OF MANGENESE, THE REMAINDER CONSISTING OF ZINC OXIDE, SAID MIXTURE OF OXIDES CONTAINING AT MOST 0.5% BY WEIGHT OF EACH OF THE TWO METALS CONSTITUTED BY BARIUM AND STRONIUM COMPRESSING SAID MASS UNDER A PRESSURE RANGING FROM, 3 TO 10 TONS PER SQ. CM. TO GIVE IT THE DESIRED CORE FORM, SUBJECTING THE COMPRESSED MASS TO A THERMAL TREATMENT WHICH COMPRISES HEATING IT FROM 2 TO 4 HOURS AT A TEMPERATURE RANGING FROM 1170* TO 1280*C. IN AN ATMOSPHERE ESSENTIALLY CONSTITUTED BY A CHEMICALLY INERT GAS, BUT CONTAINING A SMALL AMOUNT OF OXYGEN, ADJUSTING THE PERCENTAGE OF OXYGEN IN SAID ATMOSPHERE AT LEAST DURING THE LAST FIFTEEN MINUTES OF THE THERMAL TREATMENT AND DURING COOLING FROM 0.01 TO 1.2 IN VOLUME, THIS ATMOSPHERE BEING CHOSEN IN SUCH MANNER AND THE HEATING AND COOLING OPERATIONS BEING SO CONDUCTED AS TO OBTAIN A FINAL PRODUCT IN WHICH A PORTION OF THE IRON SESQUIOXIDE INITIALLY PRESENT IN THE MIXTURE HAS BEEN CHANGED INTO FEO, THIS PORTION RANGING FROM 0.2 TO 4.7 PERCENT BY WEIGHT.