Bulk rapidly solifidied magnetic materials

Claim 1

A method for producing a bulk permanent magnet having a thickness of at least 250 microns and a density of at least about 90%, which comprises the steps of: (i) melting in a container an alloy capable of exhibiting magnetic properties of the formula: (Fe.sub.1-x T.sub.x).sub.a (Nd.sub.1-y R.sub.y).sub.b (B.sub.1-z M.sub.z).sub.c wherein T is selected from Co, Ni, Cu, Mn, Cr, V, Ti, and any combination thereof; wherein R is selected from Pr, Pm, Sm, Tb, Dy, Ho, Er, Tm, and any combination thereof; wherein M is selected from Si, C, P, and any combination thereof; wherein x is from 0 to 1; y is from 0 to 1; and z is from 0 to 1; and wherein a+b+c=100 atom % and "a" is from about 60 to about 95 atom %; "b" is from about 0 to about 30 atom %; and "c" is from 0 to about 25 atom %; (ii) atomizing the molten alloy to form droplets by directing pressurized jets of an inert gas onto the molten alloy after it passes through a delivery means exiting the container; (iii) depositing the alloy droplets onto a metallic substrate positioned at a distance away from the container opening wherein (a) a majority of the alloy droplets are in a liquid or semi-liquid state when they are deposited onto the substrate, (b) the droplets are rapidly quenched upon contact with the substrate or prior rapidly quenched droplets thereon and (c) the deposition continues until the deposit is at least about 250 microns thick; and (iv) removing the deposit from the substrate and, without forming a powder of the deposit, annealing the deposit at a sufficiently elevated temperature and for a sufficient period of time to produce a bulk permanent magnet.

Claim 2

A method for producing a bulk permanent magnet having a thickness of at least 250 microns and a density of at least about 90%, which comprises the steps of: (i) melting in a container an alloy capable of exhibiting magnetic properties of the formula: (Fe.sub.1-x T.sub.x).sub.a (Nd.sub.1-y R.sub.y).sub.b (B.sub.1-z M.sub.z).sub.c wherein T is selected from Co, Ni, Cu, Mn, Cr, V, Ti, and any combination thereof; wherein R is selected from Pr, Pm, Sm, Tb, Dy, Ho, Er, Tm, and any combination thereof; wherein M is selected from Si, C, P, and any combination thereof; wherein x is from 0 to 1; y is from 0 to 1; and z is from 0 to 1; and wherein a+b+c=100 atom % and "a" is from about 60 to about 95 atom %; "b" is from about 0 to about 30 atom %; and "c" is from 0 to about 25 atom %; (ii) atomizing the molten alloy to form droplets by directing pressurized jets of an inert gas onto the molten alloy after it passes through a delivery means exiting the container; (iii) depositing the alloy droplets onto a metallic substrate positioned at a distance away from the container opening wherein (a) a majority of the alloy droplets are in a liquid or semi-liquid state when they are deposited onto the substrate, (b) the droplets are rapidly quenched upon contact with the substrate or prior rapidly quenched droplets thereon and (c) the deposition continues until the deposit is at least about 250 microns thick; and (iv) removing the deposit from the substrate and, without forming a powder of the deposit, annealing the deposit at a sufficiently elevated temperature and for a sufficient period of time to produce a bulk permanent magnet.