Patent attributes
Disclosed herein is a magnetic powder which can provide a magnet having a high magnetic flux density and excellent magnetizability and reliability especially excellent heat resisting property (heat stability). The magnetic powder is composed of an alloy composition represented by Rx(Fe1-yCoy)100-x-z-wBzAlw (where R is at least one kind of rare-earth element, x is 8.1–9.4 at %, y is 0–0.30, z is 4.6–6.8 at %, and w is 0.02–1.5 at %), the magnetic powder being constituted from a composite structure having a soft magnetic phase and a hard magnetic phase, wherein the magnetic powder has characteristics in which, when the magnetic powder is formed into an isotropic bonded magnet by mixing with a binding resin and then molding it, the irreversible susceptibility (χirr) which is measured by using an intersectioning point of a demagnetization curve in the J-H diagram representing the magnetic characteristics at the room temperature and a straight line which passes the origin in the J-H diagram and has a gradient (J/H) of −3.8×10−6 H/m as a starting point is less than 5.0×10−7 H/m, and the intrinsic coercive force (HCJ) of the magnet at the room temperature is in the range of 406–717 kA/m.
