Method of making anisotropic permanent magnets of Mn-Al-C alloys
AssigneeMatsushita Electric Industrial Co., Ltd.
InventorsYoichi Sakamoto, Nobuyuki Kato, Tadao Ohtani
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Abstract
Anisotropic permanent magnets of Mn-Al-C polycrystalline alloy are produced by warm extrusion at a temperature of 530.degree. to 830.degree. C utilizing converging or tapered dies with lubricant interposed between the polycrystalline body and the converging die. With dies of rather small semiangles, alloys with improved magnetic properties with regard to (BH)max, and especially Br are obtained.
Claims6
A method of making anisotropic permanent magnet which comprises the steps of (1) preparing a polycrystalline body of an alloy comprises of the Mn-Al-C system by melting and casting (2) subjecting said alloy to heat treatment, and (3) warm extruding at a temperature of 530.degree. to 830.degree. C in order to make said alloy anisotropic, said warm extruding step being performed by pushing said polycrystalline body through a converging die with lubricant interposed between said polycrystalline body and said converging die.
Dependencies are inferred from the claim text.