(19)
(11) EP 0 453 270 A3

(12) EUROPEAN PATENT APPLICATION

(88) Date of publication A3:
27.11.1991 Bulletin 1991/48

(43) Date of publication A2:
23.10.1991 Bulletin 1991/43

(21) Application number: 91303442.7

(22) Date of filing: 17.04.1991
(51) International Patent Classification (IPC)5: H01F 1/053
(84) Designated Contracting States:
AT BE CH DE DK ES FR GB GR IT LI LU NL SE

(30) Priority: 18.04.1990 IE 135990
04.09.1990 IE 320190
28.02.1991 IE 67191

(71) Applicant: THE PROVOST, FELLOWS AND SCHOLARS OF THE COLLEGE OF THE HOLY AND UNDIVIDED TRINITY OF QUEEN ELIZABETH NEAR DUBLIN
Dublin 2 (IE)

(72) Inventors:
  • Coey, John Michael David
    Castleknock, County Dublin (IE)
  • Sun, Hong
    Dublin 9 (IE)

(74) Representative: Baldock, Sharon Claire et al
Boult, Wade & Tennant 27 Furnival Street
London EC4A 1PQ
London EC4A 1PQ (GB)


(56) References cited: : 
   
       


    (54) Rare-earth based magnetic materials, production process and use


    (57) A new magnetic material of the general formula:

            RxFeyX′aZb

    is derived from an intermetallic compound of rhomohedral or hexagonal crystal structure wherein R is one or more rare earth elements, X′ is an element of groups IIIA, IIIB, IVA or IVB of the periodic table, Z is one or more elements of group VA of the periodic table, x is a value from 1 to 2, y is a value from 11 to 19, a is a value from 0 to 3, b is a value from 0.5 to 3 and Fe is unsubstituted or partly, substitued with the proviso that if the component Z is antimony or bismuth the element X′ is not boron.
    These new materials exhibit increased Curie temperatures, magnetic strength and easy uniaxial anisotropy and are therefore suitable for fabricating into permanent magnets. Processes for preparing materials RxFeyX′aZb are also described.





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