초록 ▼

A magnet comprising grains of a ferromagnetic material whose main component is iron and a fluorine compound layer or an oxy-fluorine compound layer of fluoride compound particles of alkali metals, alkaline earth metals and rare earth elements, present on the surface of the ferromagnetic material gra

A magnet comprising grains of a ferromagnetic material whose main component is iron and a fluorine compound layer or an oxy-fluorine compound layer of fluoride compound particles of alkali metals, alkaline earth metals and rare earth elements, present on the surface of the ferromagnetic material grains, wherein an amount of iron atoms in the fluorine compound particles is 1 to 50 atomic %.

대표청구항 ▼

What is claimed is: 1. A magnet comprising ferromagnetic material grains, wherein a main component of the ferromagnetic material grains is iron and wherein the ferromagnetic material grains have a particle size of 1 to 300 μm, and a fluorine compound layer or an oxy-fluorine compound layer,

What is claimed is: 1. A magnet comprising ferromagnetic material grains, wherein a main component of the ferromagnetic material grains is iron and wherein the ferromagnetic material grains have a particle size of 1 to 300 μm, and a fluorine compound layer or an oxy-fluorine compound layer, the fluorine compound layer or oxy-fluorine compound layer comprising fluoride or oxy-fluoride compound particles of at least one selected from the group consisting of alkali metals, alkaline earth metals and rare earth elements, and comprising iron atoms, present on and in contact with surfaces of the ferromagnetic material grains, wherein an amount of iron atoms in the fluoride or oxy-fluoride compound particles is 1 to 50 atomic %. 2. The magnet according to claim 1, wherein the fluorine compound layer or an oxy-fluorine compound layer has a crystal structure of the fluoride or oxy-fluoride compound particles, and the iron diffused into the crystal structure of the fluoride or oxy fluoride compound particles. 3. The magnet according to claim 1, wherein the ferromagnetic material grains comprise ferromagnetic powder whose composition is represented by R—Fe—B wherein R is a rare earth element, Fe is iron and B is boron. 4. The magnet according to claim 1, wherein the fluoride compound particles comprises magnetic powder whose main component is at least one of NdF3, LiF, MgF2, CaF2, ScF2, VF2, VF3, CrF2, CrF3, MnF2, MnF3, CoF2, CoF3, NiF2, ZnF2, AlF3, GaF3, SrF2, YF3, ZrF3, NbF5, AgF, InF3, SnF2, SnF4, BaF2, LaF2, LaF2, CeF3, PrF2, PrF3, NdF2, SmF2, SmF3, EuF2, EuF3, GdF3, TbF3, TbF4, DyF2, DyF3, HoF2, HoF3, ErF2, ErF3, TmF2, TmF3, YbF2, YbF3, LuF2, LuF3, PbF2, and BiF3. 5. The magnet according to claim 1, wherein an average particle size of the fluoride or oxy-fluoride compound particles is 1 to 500 nm, and the fluoride or oxy-fluoride compound particles have a higher electric resistance than an electric resistance of the ferromagnetic material grains. 6. The magnet according to claim 1, wherein the magnet has a recoil magnetic permeability of larger than 1.04, but smaller than 1.30, and a specific resistance is 0.2 mΩcm or more. 7. The magnet according to claim 1, wherein the fluorine compound layer or oxy-fluorine compound layer covers the surface of the ferromagnetic material grains in a coverage of 50 to 100%. 8. The magnet according to claim 1, wherein grains of the fluoride or oxy-fluoride compound particles grow when subjected to molding under heating. 9. The magnet according to claim 1, wherein the grains of the fluoride or oxy-fluoride compound particles have an average crystal grain size of 1 to 500 nm. 10. A magnet comprising ferromagnetic material grains, wherein a main component of the ferromagnetic material grains is iron and wherein the ferromagnetic material grains have a particle size of 1 to 300 μm, and an oxy-fluorine compound, the oxy-fluorine compound comprising oxy-fluoride particles of at least one selected from the group consisting of alkali metals, alkaline earth metals and rare earth elements, and comprising iron atoms covering and in contact with surfaces of the ferromagnetic material grains, wherein the oxy-fluoride compound particles contain 1 to 50 atomic % of iron. 11. The magnet according to claim 10, wherein the oxy-fluorine compound has a crystal structure of the oxy-fluoride particles, and the iron is diffused into the crystal structure of the fluoride compound particles. 12. The magnet according to claim 10, wherein the ferromagnetic material grains comprise ferromagnetic powder whose composition is represented by R—Fe—B wherein R is a rare earth element, Fe is iron and B is boron. 13. The magnet according to claim 10, wherein the is oxy-fluoride particles comprise magnetic powder whose main component is represented by Rw(OxFy)z wherein w,x,y are integers and R is at least one of Li, Mg, Ca, Sc, Mn, Co, Ni, Zn, Al, Ga, Sr, Y, Zr, Nb, Ag, In, Sn, Ba, La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Pb and Bi. 14. The magnet according to claim 10, wherein an average particle size of the oxy-fluoride compound particles is 1 to 500 nm, and the oxy-fluoride compound particles have a higher electric resistance than an electric resistance of the ferromagnetic material grains. 15. The magnet according to claim 10, wherein the magnet has a recoil magnetic permeability of larger than 1.04, but smaller than 1.30, and a specific resistance is 0.2 mΩcm or more. 16. The magnet according to claim 10, wherein the oxy-fluoride compound covers the surface of the ferromagnetic material grains in a coverage of 50 to 100%. 17. The magnet according to claim 10, wherein grains of the oxy-fluoride compound particles grow when subjected to molding under heating. 18. The magnet according to claim 10, wherein the grains of the oxy-fluoride compound particles have an average crystal grain size of 1 to 500 nm. 19. The magnet according to claim 10, wherein the oxy-fluorine compound is coated along grain boundaries of the ferromagnetic material grains. 20. The magnet according to claim 19, wherein the oxy-fluorine compound covers the surface of the ferromagnetic material grains in a coverage of 50 to 100%. 21. The magnet according to claim 1, wherein the fluorine compound layer or oxy-fluorine compound layer is coated along grain boundaries of the ferromagnetic material grains. 22. The magnet according to claim 21, wherein the fluorine compound layer or oxy-fluorine compound layer covers the surface of the ferromagnetic material grains in a coverage of 50 to 100%.