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The processes of magnetization reversal in isotropic and anisotropic commercial permanent magnets Sm(Co, Fe, Cu, Zr)7.5 were investigated. Features of magnetization reversal process in both textured and isotropic magnets were analyzed with δM(H) plots, magnetic susceptibility and initial magnetization curves. The magnetization reversal of Sm(Co, Fe, Cu, Zr)7.5 magnets is more complicated than that described in the coercivity model based on the domain walls pinning. © Published under licence by IOP Publishing Ltd. ; The work was supported by Act 211 Government of the Russian Federation, contract № 02.A03.21.0006.

The magnetocaloric properties of Gd ribbons processed by different kinds of mechanical treatments such as plastic deformation and ball milling were comparatively analyzed and discussed. The maximum of the temperature dependence of the magnetic entropy change for the ribbon in the initial state was as high as 11.8 J/kg•K in magnetic fields up to 7 T, i.e. it was very close to the corresponding value for the bulk gadolinium. The maximum values of the magnetic entropy change for the powder sample and the deformed sample in the same fields were as high as 3.2 and 1.9 J/kg•K respectively. © 2020 American Institute of Physics Inc. All rights reserved. ; This study was supported by the Ministry of Science and Higher Education of the Russian Federation (project No. FEUZ-2020-0051) and Proyecto Grupos, Educación Gobierno Vasco: Basque government. Project IT1245-19.

Laser based powder bed fusion is a promising manufacturing method that can be used for the fabrication of hard magnets such as NdFeB with nearly any given geometrical shape. However, the weak performance, e.g., low coercivity, of the 3D-printed magnets currently hinder their application. In this work, we demonstrated a proof-of-concept of powder bed additive manufacturing of heavy rare earth free NdFeB magnets with technologically attractive coercivity values. The 3D-printed NdFeB magnets exhibit the highest (up-to-date for the additively manufactured magnets without heavy rare earth metals) coercivity values reaching μ0Hc = 1.6 T. The magnets were synthesized using a mixture of the NdFeB-based and the low-melting eutectic alloy powders. The essential function of the eutectic alloy, along with binding of the NdFeB-based magnetic particles, is the significant improvement of their coercivity by the in-situ grain boundary (GB) infiltration. The fundamental understanding of the magnetization reversal processes in these 3D-printed magnets leads to the conclusion that the excellent performance of the additively manufactured hard magnets can be achieved through the delicate control of the intergrain exchange interaction between the grains of the Nd2Fe14B phase. © 2020 Acta Materialia Inc. ; Government Council on Grants, Russian Federation ; Ministry of Science and Higher Education of the Russian Federation: FEUZ-2020-0051 ; MA 3333/13-1 ; The financial support was provided by the German Science Foundation under the Leibniz Program (Grant MA 3333/13-1), by Act 211 Government of the Russian Federation (contract № 02.A03.21.0006), and Ministry of Science and Higher Education of the Russian Federation, Grant Number FEUZ-2020-0051.