Disclosed herein is a magnetic powder which can provide magnets having
excellent magnetic properties and having excellent reliability especially excellent
heat stability. The magnetic powder is composed of an alloy composition represented
by Rx(Fe1-aCoa)100-x-y-zByMz
(where R is at least one kind of rare-earth element excepting Dy, M is at least
one kind of element selected from Ti, Cr, Nb, V, Mo, Hf, W, Mn, Zr and Dy, x is
7.1-9.9 at %, y is 4.6-8.0 at %, z is 0.1-3.0 at %, and a is 0-0.30), and the magnetic
powder being constituted from a composite structure having a soft magnetic phase
and a hard magnetic phase, wherein when the magnetic powder is mixed with a binding
resin and then the mixture is subjected to injection molding or extrusion molding
to form a bonded magnet having a density [Mg/m3], the maximum
magnetic energy product (BH)max[kJ/m3] of the bonded magnet
at a room temperature satisfies the relationship represented by the formula (BH)max/2[10-9Jm3/g2]2.10,
and the intrinsic coercive force HCJ of the bonded magnet at a room
temperature is in the range of 400-760 kA/m.
