Patent ID: 6695929
Filing Date: 2004-02-24
Classification: B22D,B82Y,C22C,H01F

Abstract:
A method of making a material alloy for an iron-based rare earth magnet, the method comprising the steps of:preparing a melt of an iron-based rare earth material alloy, the material alloy having a composition represented by the general formula: (Fe1-mTm)100-x-y-zQxRyMz, where T is at least one element selected from the group consisting of Co and Ni; Q is at least one element selected from the group consisting of B and C; R is at least one element selected from the group consisting of Y (yttrium) and the rare earth elements; and M is at least one element selected from the group consisting of Al, Si, Ti, V, Cr, Mn, Cu, Zn, Ga, Zr, Nb, Mo, Ag, Hf, Ta, W, Pt, Au and Pb, the mole fractions x, y, z and m satisfying the inequalities of: 10 at %&lE;x&lE;30 at %; 2 at %&lE;y<10 at %; 0 at %&lE;z&lE;10 at %; and 0&lE;m&lE;0.5, respectively; feeding the melt of the material alloy onto a guide and forming a flow of the melt on the guide for transfer to a chill roller so as to move the melt onto a region where the melt comes into contact with the chill roller; rapidly cooling the melt using the chill roller to make a rapidly solidified alloy; and controlling an oxygen concentration of the melt yet to be fed onto the guide such that the oxygen concentration is about 3,000 ppm or less in mass percentage.