Werner Steck has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
Abstract: Magnetic materials which essentially consist of a phase A with a ferromagnetic spin system and a phase B with an anti-ferromagnetic spin system, phases A and B interacting by exchange coupling, and the manufacture of such materials. The materials consist essentially of two-phase magnetic single-domain particles, with the alloy [Co.sub.x Ni.sub.1.sub.-x ] as the ferromagnetic phase A and its oxidized form [(CoO).sub.x (NiO).sub.1.sub.-x ] as the anti-ferromagnetic phase B, with values of x of 0.04 to 0.96. They are manufactured by surface oxidation of a pigment layer, which at least covers the surface but may extend deeper, having the composition of phase A, to form an oxide layer, at least 40 A thick, of the phase B, followed by heating in an inert gas atmosphere, or by reduction of a corresponding layer of phase B to a layer of phase A. Magnetic single-domain particles of this composition have a Neel temperature which varies with X.
December 23, 1974
Date of Patent:
May 25, 1976
Eberhard Koester, Gerd Wunsch, Paul Deigner, Dieter Graw, Karl Uhl, Werner Steck