Global Patent Index - EP 1381578 A1

EP 1381578 A1 20040121 - METHOD FOR THE PRODUCTION OF FERRITE MAGNETS

Title (en)

METHOD FOR THE PRODUCTION OF FERRITE MAGNETS

Title (de)

VERFAHREN ZUR HERSTELLUNG EINES FERRITHALTIGEN MAGNETEN

Title (fr)

PROCEDE DE FABRICATION D'AIMANTS DU TYPE FERRITE

Publication

EP 1381578 A1 20040121 (FR)

Application

EP 02735479 A 20020423

Priority

  • FR 0201378 W 20020423
  • FR 0105569 A 20010425

Abstract (en)

[origin: WO02085810A1] The invention relates to a method for the production of ferrite permanent magnets of formula M1-X RX Fe12-yTy O19 wherein a) an MP mixture is formed from raw materials PMM, PMF, PMR et MPT respectively referring to the elements M, R, Fe and T, the raw material MPF referring to the element Fe, typically ferric oxide Fe2O3, and the raw material MPM are the main raw materials; the raw materials PMR et MPT are raw materials which are substitution materials MPS; b) said mixture is calcined in order to form a clinker B B; c) said clinker is wet milled; d) said particles are concentrated and compressed in an orienting magnetic field in order to form a green compact D which is anistropic, can be handled and and which has a predetermined form; e) the green anistropic compact is sintered in order to obtain a sintered element E . The inventive method is characterized by the following: in the MP mixture at stage a) at least one of the raw substitution materials PMR or MPT has a particle size GR which is typically measured by the specific surface BET in m<2>/g and specifically rated GR or GT for respectively the substitution materials MPR or MPT, selected according to the particle size GF of the main raw material MPF and according to the mass per cent value %S of said raw substitution material PMS with respect to said main raw material MPF, thereby resulting in square magnets having a generally high performance index.

IPC 1-7

C04B 35/32; C04B 35/40; H01F 1/10; C01G 49/00

IPC 8 full level

C01G 49/00 (2006.01); C01G 51/00 (2006.01); C04B 35/26 (2006.01); C04B 35/622 (2006.01); H01F 1/10 (2006.01); H01F 1/11 (2006.01); H01F 7/02 (2006.01); H01F 41/02 (2006.01)

CPC (source: EP KR US)

C01G 49/0018 (2013.01 - EP US); C01G 49/0036 (2013.01 - EP US); C01G 49/0063 (2013.01 - EP US); C01G 49/0072 (2013.01 - EP US); C01G 49/009 (2013.01 - EP US); C01G 51/006 (2013.01 - EP US); C04B 35/26 (2013.01 - KR); C04B 35/2608 (2013.01 - EP US); C04B 35/2633 (2013.01 - EP US); C04B 35/2641 (2013.01 - EP US); C04B 35/2683 (2013.01 - EP US); H01F 1/10 (2013.01 - EP KR US); C01P 2002/52 (2013.01 - EP US); C01P 2004/62 (2013.01 - EP US); C01P 2006/12 (2013.01 - EP US); C01P 2006/42 (2013.01 - EP US)

Citation (search report)

See references of WO 02085810A1

Designated contracting state (EPC)

AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR

DOCDB simple family (publication)

WO 02085810 A1 20021031; BR 0209180 A 20040803; CN 1330605 C 20070808; CN 1561316 A 20050105; EP 1381578 A1 20040121; FR 2824178 A1 20021031; FR 2824178 B1 20030530; JP 2004532524 A 20041021; JP 3990291 B2 20071010; KR 100870690 B1 20081127; KR 20040023795 A 20040319; MX PA03009726 A 20040129; US 2003052300 A1 20030320; US 6811718 B2 20041102

DOCDB simple family (application)

FR 0201378 W 20020423; BR 0209180 A 20020423; CN 02808826 A 20020423; EP 02735479 A 20020423; FR 0105569 A 20010425; JP 2002583347 A 20020423; KR 20037013966 A 20031024; MX PA03009726 A 20020423; US 11845102 A 20020409