Hydrogen Decrepitation Press-Less Process recycling of NdFeB sintered magnets

Authors :: Allan I. Søegaard
Asger Bech Abrahamsen
Badrinath Veluri
Manlong Xia
Christian R.H. Bahl
Poul Bøjsøe
Source :: Xia, M, Abrahamsen, A B, Bahl, C, Veluri, B, Søegaard, A I & Bøjsøe, P 2017, ' Hydrogen Decrepitation Press-Less Process Recycling of NdFeB sintered magnets ', Journal of Magnetism and Magnetic Materials, vol. 441, pp. 55-61 . https://doi.org/10.1016/j.jmmm.2017.01.049
Publication Year :: 2017
Publisher :: Elsevier BV, 2017.
Abstract: A Hydrogen Decrepitation Press-Less Process (HD-PLP) recycling method for recycling of anisotropic NdFeB magnets is demonstrated. The method combines hydrogen decrepitation (HD) disintegration of the initial magnet, powder sieving and the Press-Less Process (PLP), where hydride powder is sintered in a graphite mold. Coercivities up to 534 kA/m were obtained in porous samples based on powder size d < 100 μm. Adding a ball milling step resulted in full density isotropic magnets for d > 100 μm. The coercivity reached Hci = 957 kA/m being 86 % of the original N48M material without addition of rare earth elements.