Magnets obtained from rare earth elements are becoming increasingly important in sustaining today's lifestyle, as they are used in devices that require electric motors to operate. Especially in those that require maximum power and energy efficiency. Among other things, they are also an indispensable component of devices for data storage and power generation, such as hard drives and wind turbines. Optimising their production is therefore of great importance, because the magnetic properties depend on the manufacturing conditions. As China restricts the export of raw materials essential for the production of rare earth permanent magnets, the European Union has started to focus on building its own magnet production system from raw materials to final products. One of the projects supported by the European Union is the RECO2MAG project. The project links several research and educational institutions and companies from countries of the European Union, Montenegro and Serbia. The aim is to develop technologies for the production of high-quality Nd-Fe-B magnets. As a part of this project, we optimised the parameters for traditional vacuum sintering and heat treatment of R33 powder provided by Magneti Ljubljana d.d. The results obtained were used to compare the traditional approach with spark plasma sintering. The first step in preparing the magnets is to make an elastic mould into which we pour the powder, magnetically align it and isostatically compact it. This was followed by optimizing vacuum sintering and finally the heat treatment process. Through the latter, we obtain the final magnetic properties of the magnets. To determine the appropriate conditions, we measured the density and magnetic properties after sintering. After optimising the parameters for vacuum sintering, we also determined the optimal conditions for heat treatment. The results are analysed and the microstructures of selected sintered and heat-treated samples are compared.
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