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PROBLEM TO BE SOLVED : To provide a permanent magnet that allows high-temperature demagnetization to be suppressed while maintaining high coercive force and magnetic flux density of an Sm-Co system magnet.
SOLUTION : A permanent magnet 1 comprises : a magnet main body 2 having a composition represented by a composition formula 1 of R(Fep1Mq1Cur1Co1-p1-q1-r1)z1; and a surface portion 3 having a composition represented by a composition formula 2 of R(Fep2Mq2Cur2Co1-p2-q2-r2)z2. In the composition formula 1 and the composition formula 2, R is at least one kind of element selected from rare earth elements, and M is at least one kind of element selected from Ti, Zr and Hf. Atomic ratios of p1 and p2 range from 0.25 to 0.45, atomic ratios of q1 and q2 range from 0.01 to 0.05 and atomic ratios of r1 and r2 range from 0.01 to 0.1. An atomic ratio of z1 ranges from 6 to 9, and an atomic ratio of z2 satisfies an expression of 0.8≤z2/z1≤0.995.
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