Establishing the recycling process of NdFeB magnets has become more important in recent years as the need for those magnets is increasing, but supplies of the ore containing rare earth elements (REE) are decreasing. Moreover, production of REE from ore is very harmful to the environment. The biggest interest lies in the ‘’magnet to magnet’’ recycling process where waste magnets are directly transformed by hydrogenation and jet milling into recycled powder for further production of new magnets, which is the economically and ecologically the best solution out of the current processing methods of magnets. Most studies on magnets recycling are still carried out on the laboratory scale, so the recycling process under industrial conditions is only partially successful in achieving similar magnetic measurement results. Due to poor research of recycling NdFeB waste magnets on the industry scale, this work will focus on improving the remanence of recycled magnets by adding additives to modify the composition and on the production of magnets containing at least 30% of recycled powder. In the first part of the experimental work, we turned waste magnets into fine powder with hydrogen decrepitation process and jet milling. In the second part, experiments were carried out with mixtures with different proportions of additives (NdHx and fresh material) and their effect on the density and magnetic properties of the samples was studied. Based on the analysis of the experiments carried out in the second part, we made final products with the highest possible remanence in the third part of the experimental work. Microstructure and magnetic properties of the finished products were compared with properties of the waste magnets. By comparing them, we could see changes in the microstructure and magnetic properties of recycled magnets, which are mainly dependent on the recyclable content.
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