%0 Journal Article %T High-coercivity copper-rich Nd-Fe-B magnets by powder bed fusion using laser beam method %+ Département des Technologies des NanoMatériaux (DTNM) %+ VTT Technical Research Centre of Finland (VTT) %+ Technische Universität Darmstadt - Technical University of Darmstadt (TU Darmstadt) %A Tosoni, Olivier %A Mendonça, Elisa Borges %A Reijonen, Joni %A Antikainen, Atte %A Schäfer, Lukas %A Riegg, Stefan %< sans comité de lecture %@ 2214-8604 %J Additive Manufacturing %I Elsevier %V 64 %P 103426 %8 2023 %D 2023 %R 10.1016/j.addma.2023.103426 %Z Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci]Journal articles %X Additive manufacturing (AM) is an attractive processing route to make efficient use of rare-earths in systems containing complex-shaped rare-earth based magnets. Powder bed fusion using laser beam (PBF-LB) is one of the most promising technologies to obtain fully dense printed parts and has seen significant recent research. However, most works use commercial NdFeB-type powders with a composition more suited for binder based AM methods, which reduces the printing parameter window and does not allow property enhancement by the application of annealing cycles. In this work, a close-to-industrial process route was developed in order to produce a narrow-distributed 40-µm Nd-Fe-B powder, derived from strip casting, hydrogen decrepitation and milling, with a composition close to the usual sintered magnet grades. The composition was adjusted by preliminary small-scale experiments focused on the reduction of cracking and the promotion of fine-grained equiaxed microstructures. This powder was then used to build magnets by the PBF-LB method. The best magnetic properties could be achieved with building conditions providing just enough energy to completely melt the material, yielding nano-grained microstructures almost deprived of α-Fe phase. After laser parameter optimization and post-process annealing, properties of B$_r$ = 0.62T, H$_{cj}$ = 1790 kA.m$^{-1}$ and BH$_{max}$ = 65 kJ.m$^{-3}$ were obtained. %G English %2 https://cea.hal.science/cea-04097536/document %2 https://cea.hal.science/cea-04097536/file/Article%20PBF-LB%20NdFeB%20after%20second%20review.pdf %L cea-04097536 %U https://cea.hal.science/cea-04097536 %~ CEA %~ UNIV-SAVOIE %~ CNRS %~ DRT %~ LITEN %~ CEA-GRE %~ INES %~ MAP-CEA