Permanent magnet and method for producing same

Abstract

In the rare earth-iron-boron permanent magnet, Ce and La decrease the magnetic properties when used alone but synergistically enhance iHc when used in combination. The composition provided by the present invention is generally expressed by [(Ce x La 1-x ) y R 1-y ] 2 [(Fe 1-u-w Co w M u ) 1-v B v ] 1-z with a proviso of 0.4≦x≦0.9, 0.2<y≦1.0, 0.05≦z≦0.3, 0.01≦v≦0.3, 0≦u≦0.2, 0≦w≦0.5, and M is at least one element selected from the group consisting of Al, Ti, V, Cr, Mn, Zr, Hf, Nb, Ta, Mo, Ge, Sb, Sn, Bi, Ni, W, Cu, and Ag.

We claim: 
     
       1. A permanent .[.magnet.]. .Iadd.magnetic powder or ribbon obtained by the rapid cooling method and .Iaddend.having a composition expressed by (Ce x  La 1-x ) z  (Fe 1-v  B v ) 1-z , with a proviso of 0.4≦x≦0.9, 0.05≦z≦0.3, and 0.01≦v≦0.3 and having a coercive force (iHc) of at least 4 kOe. .[.2. A permanent magnet according to claim 1, wherein said permanent magnet is a sintered magnet..]. .[.3. A permanent magnet according to 
     
     
        claim 1, wherein said permanent magnet is a bonded magnet..]. 4. A permanent .[.magnet.]. .Iadd.magnetic powder or ribbon .Iaddend.according to claim 1, wherein x is from 0.6 to 0.8, v is from 0.02 to 0.15, and z is 
     
     
        from 0.1 to 0.2.  5. A permanent .[.magnet.]. .Iadd.magnetic powder or ribbon .Iaddend.according to claim .[.2.]. .Iadd.1.Iaddend., wherein v is 
     
     
        from 0.03 to 0.12.  6. A permanent .[.magnet.]. .Iadd.magnetic powder or ribbon .Iaddend.according to claim .[.2.]. .Iadd.1.Iaddend., wherein x is 
     
     
        approximately 0.65.  7. A permanent magnet .[.according to claim 1, 2, 3, 4, 5, or 6, wherein.]. .Iadd.formed from a rapidly cooled magnetic material having a composition expressed by (Ce x  La 1-x ) z  (Fe 1-v  B v ) 1-z , with a proviso of 0.4≦x≦0.9, 0.05≦z≦0.3, and 0.01≦v≦0.3 and containing .Iaddend.at least one element selected from the group consisting of Al, Ti, V, Cr, Mn, Zr, Hf, Nb, Ta, Mo, Ge, Sb, Sn, Bi, Ni, W, Cu, and Ag .[.is contained.]. at an atomic ratio .Iadd.u .Iaddend.of .Iadd.0<u≦.Iaddend.0.2 .[.or less.]. based on the sum of said at least one element and Fe .Iadd.and having a coercive force (iHC) of at 
     
     
        least 4 KOe.Iaddend.. 8. A permanent magnet according to claim .[.1, 2, 3, 4, 5, or 6.]. .Iadd.7 or 9.Iaddend., wherein B is partly replaced with at least one element selected from the group consisting of Si, C, P, N, Ge, and S in an atomic ratio of 0.5 or less based on a sum of B and said at 
     
     
        least one element. 9. A permanent magnet according to claim .[.1.]. .Iadd.7.Iaddend., wherein Co is contained at an atomic ratio (w) and at least one element selected from the group consisting of Al, Ti, V, Cr, Mn, Zr, Hf, Nb, Ta, Mo, Ge, Sb, Sn, Bi, Ni, W, Cu and Ag is contained at an atomic ratio (u), wherein said (w) is from more than 0 to 0.5 and said (u) is from .[.0.]. .Iadd.0.001 .Iaddend.to 0.2, with the proviso that sum of 
     
     
        (u), (w) and atomic ratio of Fe is 1.0. 10. A permanent magnet according to claim .Iadd.7 or .Iaddend.9, wherein said permanent magnet is a 
     
     
        sintered magnet. 11. A permanent magnet according to claim .Iadd.7 or 
     
     
        .Iaddend.9, wherein said permanent magnet is a bonded magnet. 12. A permanent magnet according to claim .Iadd.7 or .Iaddend.9, wherein x is 
     
     
        from 0.6 to 0.8, v is from 0.02 to 0.15, and z is from 0.1 to 0.2. 13. A permanent magnet according to claim .[.10.]. .Iadd.7 or 9.Iaddend., 
     
     
        wherein v is from 0.03 to 0.12. 14. A permanent magnet according to claim .[.10.]. .Iadd.7 or 9.Iaddend., wherein x is approximately 0.65. .[.15. A permanent magnet having a composition of [(Ce x  La 1-x ) y  R 1-y  ] z  (Fe 1-v  B v ) 1-z , wherein R is at least one rare earth element except for Ce and La, but including Y with a proviso of 0.4≦x≦0.9, 0.2<y<1.0, 0.05≦z≦0.3, 0.001≦v≦0.3, and having a coercive force (iHc) of at least 4 kOe..]. .[.16. A permanent magnet according to claim 15, wherein said permanent magnet is a sintered magnet..]. .[.17. A permanent magnet according to claim 15, wherein said permanent magnet is a bonded 
     
     
        magnet..]. 18. A permanent .[.magnet.]. .Iadd.magnetic powder or ribbon .Iaddend.according to claim .[.15.]. .Iadd.34.Iaddend., wherein x is from 
     
     
        0.6 to 0.8, v is from 0.02 to 0.15, and z is from 0.1 to 0.2. 19. A permanent .[.magnet.]. .Iadd.magnetic powder or ribbon .Iaddend.according 
     
     
        to claim .[.18.]. .Iadd.34.Iaddend., wherein v is from 0.03 to 0.12. 20. A permanent .[.magnet.]. .Iadd.magnetic powder or ribbon .Iaddend.according to claim .[.19.]. .Iadd.34.Iaddend., wherein x is approximately 0.65. .[.21. A permanent magnet according to claim 15, 16, 17, 18, 19, or 20, wherein at least one element selected from the group consisting of Al, Ti, V, Cr, Mn, Zr, Hf, Nb, Ta, Mo, Ge, Sb, Sn, Bi, Ni, W, Cu, and Ag is contained at an atomic ratio of 0.2 or less based on the sum of said at 
     
     
        least one element and Fe..]. 22. A permanent magnet according to claim .[.15, 16, 17, 18, 19 or 20.]. .Iadd.23 or 31.Iaddend., wherein B is partly replaced with at least one element selected from the group consisting of Si, C, P, N, Ge, and S in an atomic ratio of 0.5 or less 
     
     
        based on a sum of B and said at least one element. 23. A permanent magnet according to claim .[.15.]. .Iadd.31.Iaddend., wherein Co is contained at an atomic ratio (w) and at least one element selected from the group consisting Al, Ti, V, Cr, Mn, Zr, Hf, Nb, Ta, Mo, Ge, Sb, Sn, Bi, Ni, W, Cu, and Ag is contained at an atomic ratio (u), wherein said (w) is from more than 0 to 0.5 and said (u) is from .[.0.]. .Iadd.0.001 .Iaddend.to 0.2, with the proviso that sum of (u), (w) and atomic ratio of Fe is 1.0. 
     
     
         4. A permanent magnet according to claim 23 .Iadd.or 31.Iaddend., wherein 
     
     
        said permanent magnet is a sintered magnet. 25. A permanent magnet according to claim 23 .Iadd.or 31.Iaddend., wherein said permanent magnet 
     
     
        is a bonded magnet. 26. A permanent magnet according to claim 23 .Iadd.or 31.Iaddend., wherein x is from 0.6 to 0.8, v is from 0.02 to 0.15, and z 
     
     
        is from 0.1 to 0.2. 27. A permanent magnet according to claim .[.26.]. 
     
     
        .Iadd.23 or 31.Iaddend., wherein v is from 0.03 to 0.12. 28. A permanent magnet according to claim .[.26.]. .Iadd.23 or 31.Iaddend., wherein x is approximately 0.65. .[.29. A permanent magnet having a composition of [(Ce x  La 1-x ) y  R 1-y  ] z  [(Fe 1-u-w  Co w  M u ) 1-v  B v  ] 1-z  with a proviso of 0.4≦x≦0.9, 0.2<y≦1.0, 0.05≦z≦0.3, 0.01≦v≦0.3, 0≦u≦0.2, 0≦w≦0.5, and M is at least one element selected from the group consisting of Al, Ti, V, Cr, Mn, Zr, Hf, Nb, Ta, Mo, Ge, Sb, Sn, Bi, Ni, W, Cu, and Ag, having a coercive force (iHc) of at least 4 kOe, having been plastically 
     
     
        worked. 30. A permanent magnet according to claim .[.29.]. .Iadd.33.Iaddend., wherein the plastic working method is a method selected from the group consisting of hot-pressing, swaging, extruding, forging, and rolling. .Iadd.31. A permanent magnet formed from a rapidly cooled magnetic material having a composition of [((Ce x  La 1-x ) y  R 1-y ) z  ]((Ce x  La 1-x ) y  R 1-y ) z  (Fe 1-v  B v ) 1-z  wherein R is at least one rare earth element except for Ce and La, but including Y with a proviso of 0.4≦x≦0.9, 0.2<y<1.0, 0.05≦z≦0.3, 0.01≦v≦0.3 containing at least one element selected from the group consisting of Al, Ti, V, Cr, Mn, Zr, Hf, Nb, Ta, Mo, Ge, Sb, Sn, Bi, Ni, W, Cu, and Ag at an atomic ratio u of 0<u≦0.2 based on the sum of said at least one element and Fe, having a coercive force (iHc) of at least 4 KOe. .Iaddend. .Iadd.32. A permanent magnet formed of a magnetic powder of claims 1 or 34. .Iaddend. .Iadd.33. A permanent magnet having a composition of ((Ce x  La 1-x ) y  R 1-y ) z  (Fe 1-u-w  Co w  M u ) 1-y  B v  ] 1-z  with a proviso of 0.4≦x≦0.9, 0.2<y<1.0, 0.05≦z≦0.3, 0.01≦v≦0.3, 0≦u≦0.2, 0≦w≦0.5, and M is at least one element selected from the group consisting of Al, Ti, V, Cr, Mn, Zr, Hf, Nb, Ta, Mo, Ge, Sb, Sn, Bi, Ni, W, Cu, and Ag having a coercive force (IiHc) of at least 4 kOe, comprising a rapidly cooled magnetic material which has been plastically worked. .Iaddend. .Iadd.34. A permanent magnetic powder or ribbon obtained by a rapid cooling method having a composition of ((Ce x  La 1-x ) y  R 1-y ) z  (Fe 1-v  B v ) 1-z , wherein R is at least one rare earth element except for Ce and La but including Y with a proviso of 0.4≦x≦0.9, 0.2<y<1.0, 0.5≦z≦0.3, 0.01≦v≦0.3, and having a coercive force (iHc) of at least 4 KOe. .Iaddend.