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Artificially produced rare-earth free cosmic magnet

Chemically ordered hard magnetic L1(0)-FeNi phase of higher grade than cosmic meteorites is produced artificially. Present alloy design shortens the formation time from hundreds of millions of years for natural meteorites to less than 300 hours. Electron diffraction detects four-fold 110 superlattic...

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Detalles Bibliográficos
Autores principales: Makino, Akihiro, Sharma, Parmanand, Sato, Kazuhisa, Takeuchi, Akira, Zhang, Yan, Takenaka, Kana
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Nature Publishing Group 2015
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4644987/
https://www.ncbi.nlm.nih.gov/pubmed/26567704
http://dx.doi.org/10.1038/srep16627
Descripción
Sumario:Chemically ordered hard magnetic L1(0)-FeNi phase of higher grade than cosmic meteorites is produced artificially. Present alloy design shortens the formation time from hundreds of millions of years for natural meteorites to less than 300 hours. Electron diffraction detects four-fold 110 superlattice reflections and a high chemical order parameter (S [Image: see text] 0.8) for the developed L1(0)-FeNi phase. The magnetic field of more than 3.5 kOe is required for the switching of magnetization. Experimental results along with computer simulation suggest that the ordered phase is formed due to three factors related to the amorphous state: high diffusion rates of the constituent elements at lower temperatures when crystallizing, a large driving force for precipitation of the L1(0) phase, and the possible presence of L1(0) clusters. Present results can resolve mineral exhaustion issues in the development of next-generation hard magnetic materials because the alloys are free from rare-earth elements, and the technique is well suited for mass production.