Controlled catalyst for manufacturing magnetic alloy particles having

Abstract

This invention provides techniques for producing unique cobalt-phosphorus (Co-P) particles. The Co-P particles produced by this technique are novel as to both size and morphology. Their size is uniformly less than about 300 A, with average sizes being about 150 A. This is substantially smaller than Co-P particles previously known or reported in the literature. Their morphology is unique, as shown by x-ray and electron diffraction, in that they are amorphous. All known prior art Co-P particles have been crystalline. In addition, these Co-P particles have the capability of being manufactured with selectively controlled magnetic coercivity. The new reaction system utilized to produce these unique materials provides a substantial departure from art known systems. The reaction system is notable for changes in materials and procedures previously considered important or indispensable to the production of magnetic Co-P and for its ability to control the coercivity of the particles produced over a broad range as an inverse function of the concentration of the palladium cation (Pd.sup.+.sup.+) catalyst used. More specifically, the reaction system is extremely novel in terms of the fact that: (1) it is initiated at ambient rather than elevated temperatures; (2) excludes all complexing agents, both strong and weak, from the reaction system; (3) excludes magnetic fields of every form and magnitude during the reaction; and (4) can be utilized to provide Co-P particles of selected coercivity in the range of about 500 to 1500 oersteds as an inverse function of the Pd cation catalyst concentration utilized.