Global Patent Index - EP 4066963 A1

EP 4066963 A1 20221005 - METHOD OF FORMING A STARTING MATERIAL FOR PRODUCING RARE EARTH PERMANENT MAGNETS FROM RECYCLED MATERIALS AND CORRESPONDING STARTING MATERIAL

Title (en)

METHOD OF FORMING A STARTING MATERIAL FOR PRODUCING RARE EARTH PERMANENT MAGNETS FROM RECYCLED MATERIALS AND CORRESPONDING STARTING MATERIAL

Title (de)

VERFAHREN ZUR HERSTELLUNG EINES AUSGANGSMATERIALS ZUR HERSTELLUNG VON SELTENERD-DAUERMAGNETEN AUS RECYCELTEN MATERIALIEN UND ENTSPRECHENDES AUSGANGSMATERIAL

Title (fr)

PROCÉDÉ DE FORMATION D'UN MATÉRIAU DE DÉPART POUR PRODUIRE DES AIMANTS PERMANENTS AUX TERRES RARES À PARTIR DE MATÉRIAUX RECYCLÉS ET MATÉRIAU DE DÉPART CORRESPONDANT

Publication

EP 4066963 A1 20221005 (EN)

Application

EP 21165521 A 20210329

Priority

EP 21165521 A 20210329

Abstract (en)

The present invention relates to a method of forming a starting material for producing rare earth permanent magnets from recycled materials. The method comprises at least the steps of providing single Nd<sub>2</sub>Fe<sub>14</sub>B grains of end-of-life Nd<sub>2</sub>Fe<sub>14</sub>B magnets and/or magnet scraps and coating the grains with a single layer or with a layer sequence of one or several grain boundary materials such that said single layer or layer sequence is covering each individual grain. The grain boundary material of said single layer or of a lowermost layer of said layer sequence is selected from one or several metals or metal compounds or alloys. The coated grains are then condensed to bulk Nd-Fe-B permanent magnets, optionally via subsequent thermal treatments.

IPC 8 full level

B22F 1/00 (2022.01); B22F 8/00 (2006.01); B22F 9/02 (2006.01); C22B 7/00 (2006.01); C22B 59/00 (2006.01); C22C 38/00 (2006.01); C23C 16/00 (2006.01); C30B 29/52 (2006.01); H01F 1/057 (2006.01); H01F 41/02 (2006.01); B22F 9/00 (2006.01)

CPC (source: EP)

B22F 1/05 (2022.01); B22F 1/145 (2022.01); B22F 1/16 (2022.01); B22F 1/17 (2022.01); B22F 8/00 (2013.01); B22F 9/023 (2013.01); C23C 28/00 (2013.01); H01F 1/0572 (2013.01); H01F 1/0578 (2013.01); H01F 41/0253 (2013.01); B22F 2009/001 (2013.01); B22F 2998/10 (2013.01); B22F 2999/00 (2013.01); C22C 2200/00 (2013.01); C22C 2202/02 (2013.01); H01F 1/0573 (2013.01)

C-Set (source: EP)

  1. B22F 2999/00 + C22C 2202/02 + B22F 2009/001
  2. B22F 2999/00 + C22C 2202/02 + B22F 8/00
  3. B22F 2998/10 + B22F 1/145 + B22F 9/023 + B22F 8/00
  4. B22F 2999/00 + B22F 1/145 + C22C 2202/02 + C22C 2200/00 + B22F 1/05
  5. B22F 2999/00 + B22F 1/145 + B22F 1/17
  6. B22F 2999/00 + B22F 1/145 + B22F 1/17 + B22F 1/102 + B22F 1/16

Citation (applicant)

  • CN 104959618 A 20151007 - UNIV ZHEJIANG
  • CN 110853854 A 20200228 - UNIV BEIJING TECHNOLOGY
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  • SEPEHRI-AMIN, H. ET AL.: "Grain boundary and interface chemistry of an Nd-Fe-B-based sintered magnet", ACTA MATERIALIA, vol. 60, no. 3, 2012, pages 819 - 830, XP028445602, DOI: 10.1016/j.actamat.2011.10.043
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Citation (search report)

Designated contracting state (EPC)

AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

Designated extension state (EPC)

BA ME

DOCDB simple family (publication)

EP 4066963 A1 20221005

DOCDB simple family (application)

EP 21165521 A 20210329