20.500.12556/RUL-94351 Izdelava NdFeB magnetov z izboljšanimi magnetnimi lastnostmi iz recikliranega materiala Production of NdFeB magnets with improved magnetic properties using recycled material Reciklaža NdFeB-magnetov postaja vse pomembnejša, saj je potreba po teh magnetih vse večja, zaloge redkih zemelj za izdelavo magnetov je vse manj, njihovo pridobivanje iz rud pa je okolju zelo škodljivo. Največ zanimanja je za proces reciklaže, pri katerem se odpadne magnete s hidrogeniranjem in mletjem s plinskim curkom neposredno predela v recikliran prah za izdelavo novih magnetov, kar je trenutno ekonomsko in ekološko najboljša rešitev za predelava magnetov. Večina raziskav reciklaže trenutno še vedno poteka na laboratorijskem nivoju, zato je postopek reciklaže v industrijskih pogojih le delno uspešen pri doseganju podobnih rezultatov magnetnih meritev. Zaradi slabe raziskanosti reciklaže odpadnih NdFeB-magnetov na nivoju industrijske predelave se to diplomsko delo osredotoča na izboljšavo remanence recikliranih magnetov z dodajanjem dodatkov za modifikacijo sestave in izdelavo končnega izdelka, ki vsebuje vsaj 30 % reciklata. V prvem delu praktičnega dela smo pripravili prah s pomočjo postopka hidrogeniranja in mletja. V drugem delu smo izvedli poizkuse z mešanicami z različnimi deleži dodatkov (NdHx in svež material) in preučili njihov vpliv na gostoto in magnetne lastnosti vzorcev. Na podlagi analiz poizkusov, izvedenih v drugem delu, smo v tretjem delu izdelali končne izdelke s čim višjo remanenco. Mikrostrukturo in magnetne lastnosti končnih izdelkov smo primerjali z odpadnimi magneti. S primerjavo smo lahko videli spremembe v mikrostrukturi in magnetnih lastnostih recikliranih magnetov, ki so odvisne predvsem od deleža reciklata. 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. reciklaža NdFeB odpadnih magnetov tehnologija izdelave trajnih magnetov metalurgija prahov hidrogeniranje izboljšava magnetnih lastnosti mikrostruktura recycling waste NdFeB magnets permanent magnet production technology powder metallurgy hydrogen decrepitation magnetic properties improvement microstructure true false false Slovenski jezik Angleški jezik Diplomsko delo/naloga 2017-08-01 07:15:21 2017-08-01 07:15:30 2022-08-10 01:36:35 0000-00-00 00:00:00 2017 0 0 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 55380 1690719 172.pdf 172.pdf 1 2DDC1B2CF5641E4529D8603BC95DB8DC e9ca23a9ede9c362f2a0ffbb7825c9291b5ecbb0ab2b621d3988d74d9b0f03b8 81e291f7-a1b3-11eb-a523-00155dcfd717 20.500.12556/rul/45978841-74d8-4bf3-bf1e-abe77663137d https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=102557 Naravoslovnotehniška fakulteta 0 0 0