The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 03, 1984
Filed:
Sep. 30, 1982
Eugene B Rigby, Tucson, AZ (US);
International Business Machines Corp., Armonk, NY (US);
Abstract
A manufacturing process for making a finer ferrite powder which can then be used to make a very dense block of the ferrite ceramic. The process for making the powder includes the steps of co-precipitation of an aqueous solution of metal ions and an ammonium oxalate solution. The co-precipitation particles are separated, washed and dried. The particles are low-temperature calcined and then vibro-energy or ball milled and dried. The particles are fluffed and broken up in a blender and pressed into a mold for sintering and pressing in a hot isostatic press procedure. The ferrite blocks are then post annealed in an oxygen atmosphere and cooled to form a dense magnetic ceramic particle. Preferably the process is for use in the production of nickel-zinc ferrite used for magnetic heads.