Patent ID: 6890392

Claim:
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: (Fe 1-m T m ) 100-x-y-z-n (B 1-p C p ) x R y Ti 2 M n , where T is at least one element selected from the group consisting of Co and Ni; 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, V, Cr, Mn, Cu, Zn, Ga, Zr, Nb, Mo, Ag, Hf, Ta, W, Pt, Au and Pb, the mole fractions x, y, z, m, n and p satisfying the inequalities of: 10 at %<x≦25 at %; 6 at %≦y<10 at %; 0.5 at %≦z≦12 at %; 0≦m≦0.5; 0 at %≦n≦10 at %; and 0≦p≦0.25, respectively; feeding the melt of the material alloy onto a guide having a guide surface that defines an angle of about 1 degree to about 80 degrees with respect to a horizontal plane so as to move the melt onto a region where the melt comes into contact with a chill roller; and rapidly cooling the melt using the chill roller to make a rapidly solidified alloy comprising an R 2 Fe 14 B phase at about 60 volume percent or more and an iron-based boride phase, said iron-based borlde phase having ferromagnetic properties and existing around a grain boundary or sub-boundary of the R 2 Fe 4 B phase.