Investigations into the processing and texture of Pr-substituted NdFeB magnets produced by extrusion

Investigations into the processing and texture of Pr-substituted NdFeB magnets produced by extrusion

RÜDIGER Alexander, GALL Sven, MÜLLER Sören

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Abstract. Crystallographically and magnetically textured but dimensionally limited NdFeB permanent magnets produced by hot deforming processes such as die-upsetting and back-extrusion have been extensively researched in the past [1]. In order to investigate the possibility of producing longer magnets which can subsequently be cut to the required length, the extrusion of permanent magnets was investigated as a further hot deformation process. For this purpose, the process control with regard to the tools used as well as the process parameters were modified from the common forming processes for extrusion. Therefore, a praseodymium-substituted NdFeB powder was encapsulated in steel and extruded by varying the extrusion ratio (9.9:1 & 13.9), the billet insert temperature (800°C & 850°C) and the extrusion speed (0.6 – 10.5 mm/s). In addition, the glass lubrication system was changed during the experiments. Since the resulting magnetic properties for hot deformation depend on the produced anisotropy, texture analyses were also carried out in the first step by means of X-ray diffraction on the cross-sections of the produced strands. For the parameter variation, strands could be realized with the applied concept. However, cracks were found in the magnetic material for all tests. Based on the texture analyses, anisotropy could be generated in the magnet material for all strands.

Pr/NdFeB, Anisotropic Magnets, Extrusion, Hot Deformation

Published online 4/19/2023, 10 pages
Copyright © 2023 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: RÜDIGER Alexander, GALL Sven, MÜLLER Sören, Investigations into the processing and texture of Pr-substituted NdFeB magnets produced by extrusion, Materials Research Proceedings, Vol. 28, pp 505-514, 2023


The article was published as article 55 of the book Material Forming

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