The effects of dry grinding processing parameters on the electromagnetic and geometrical properties of Nd2Fe14B permanent magnets

The effects of dry grinding processing parameters on the electromagnetic and geometrical properties of Nd2Fe14B permanent magnets

Lorenzo Cestone, Erica Liverani, Alessandro Ascari, Alessandro Fortunato

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Abstract. The automotive industry has grown increasingly interested in electric propulsion over the past few years, which has led to an increase in engine and battery efficiency improvements. The study of rare earth permanent magnets has recently become essential for the development and improvement of electric engines because rotors are constructed of permanent magnets that interact with the stator windings. Due to its strong remanence and coercive field, neodymium magnet is the most frequent rare earth employed in electric motors. Nd2Fe14B magnets are made by sintering in the simple geometries of prismatic, cubic, and cylindrical, and they typically require machining to achieve the final shape necessary for the construction and assembly of the rotor. However, prismatic Nd2Fe14B row materials that have just been sintered are extremely brittle and challenging to produce; as a result, they are typically finished through grinding with a CBN grinding wheel. This study’s objective is to evaluate the effects of a dry grinding process with a wet traditional one through an experimental campaign. Process parameters such as cutting speed and feed rate were varied and surface roughness and morphology were compared, together with the magnetic field loss due to the increment of the temperature occurring during the processes. Due to the large number of electric motors that are anticipated to be manufactured in the upcoming years, dry grinding could represent the turning point in terms of eco-sustainability of the process.

Grinding, Cubic Boron Nitride (CBN)

Published online 9/5/2023, 8 pages
Copyright © 2023 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: Lorenzo Cestone, Erica Liverani, Alessandro Ascari, Alessandro Fortunato, The effects of dry grinding processing parameters on the electromagnetic and geometrical properties of Nd2Fe14B permanent magnets, Materials Research Proceedings, Vol. 35, pp 444-451, 2023


The article was published as article 53 of the book Italian Manufacturing Association Conference

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