State-of-the-art additive manufacturing of NdFeB permanent magnets: challenges and pathways toward high performance

This review critically evaluates additive manufacturing routes for neodymium–iron–boron (NdFeB) permanent magnets by benchmarking remanence and energy density to explain how processing variables and inherent manufacturing constraints limit magnetic performance relative to conventional sintered and bonded magnets. Reported remanence values for additively manufactured NdFeB magnets generally fall between 0.6 and 1.0 T. Among the available routes, material extrusion (MEX) currently represents the most competitive additive manufacturing pathway for bonded NdFeB magnets, although remanence remains below sintered anisotropic grades (1.4 to 1.5 T). By contrast, laser-based routes such as selective laser melting offer significant geometric flexibility but are effectively limited by the absence of demonstrated magnetic texture development, while selective laser sintering and binder jetting remain constrained by intrinsic porosity. For non-laser-based routes, magnetic performance is largely determined by feedstock design, including NdFeB filler fraction, alignment strategies, and post-processing treatments. Overall, additive manufacturing can reproduce the performance of commercial anisotropic bonded NdFeB magnets, with the highest remanence achieved through aligned MEX routes. These insights guide the development of advanced magnetic materials and functional devices enabled by additive manufacturing for high-performance traction motors, as well as sensors and actuators in wearable and biomedical devices.