Permanent magnetic material and permanent magnet
AssigneeAkihisa Inoue
InventorsAkihisa Inoue, Akira Takeuchi
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Abstract
With the object of improving magnetic properties by remaining amorphous phase of a quenched R—Fe—B permanent magnet, in a quenched permanent magnetic material comprising Fe as a major component, at least one lanthanoid element, R, and boron, the permanent magnetic material comprises 10 percent by area or less of a soft magnetic remaining amorphous phase, and the balance being a crystalline phase substantially formed by heat treatment and containing R—Fe—B hard magnetic compound. A bulk magnet is made of the permanent magnetic material by plastic forming.
Claims6
A permanent magnet obtained by binding with a resin a powder of quenched permanent magnetic material comprising Fe, at least one lanthanoid element R, and boron, the permanent magnetic material comprising about 2-10 percent of a soft magnetic amorphous phase and a balance being a crystalline phase containing an R—Fe—B hard magnetic compound;
- wherein boron and a lanthanoid element exist in said amorphous phase at a concentration which is higher than a concentration in said crystalline phase;
- wherein the composition of the permanent magnetic material expressed by atomic percent is FeaRbBc, 40≦a<91, 4.5≦b≦35, 0.5≦c≦30, 9.5≦b+c;
- and
- wherein said quenched permanent magnetic material has a residual magnetic flux density Br of at least 0.96 T.
A quenched permanent magnetic material comprising Fe, at least one lanthanoid element R, boron and an element X, X being at least one element selected from the group of Cd, Au, In, Mg, Pd, Pt, Ru, Sn and Zn, wherein the permanent magnetic material comprises about 2-10 percent of a soft magnetic amorphous phase and a balance is a crystalline phase containing an R—Fe—B hard magnetic compound;
- wherein said crystalline phase further includes a soft magnetic material phase smaller than the width of a domain wall of the permanent magnetic material;
- and
- wherein said boron and said lanthanoid element exist in said amorphous phase at a concentration which is higher than a concentration in said crystalline phase;
- wherein the composition of the permanent magnetic material expressed by atomic percent is FeaRbBcXd, 40≦a<91, 4.5≦b≦35, 0.5≦c≦30, 0≦d≦5, 9.5≦b+c;
- and
- wherein said quenched permanent magnetic material has a residual magnetic flux density Br of at least 0.96 T.
Dependencies are inferred from the claim text.