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Information × Registration Number 0213U000360, 0112U002794 , R & D reports Title Development of hydrogen technologies of microstructure refining of R2Fe14B-based alloys for improvement of permanent magnets properties popup.stage_title Head Bulyk Ihor, Доктор технічних наук Registration Date 01-02-2013 Organization Karpenko Physico-Mechanical Institute of the National Academy of Science of Ukraine popup.description2 The object of research is peculiarities of initiated by low hydrogen pressure phase transformations in the Nd2Fe13.8Zr0.2B and Nd16Fe73.9Zr2.1B8 alloys. Aim of study is examination of the morphology and crystallite size dependence of ferromagnetic phase doped by zirconium Nd2Fe14B compound from hydrogen treatment conditions by means of hydrogenation, disproportionation, desorption, recombination (HDDR). The following methods were used: differential thermal analysis (DTA), X-ray phase analysis (XRD), electron microscopy and elemental analysis. Nd2Fe13,8Zr0,2B and Nd16Fe73,9Zr2,1B8 alloys were investigated after milling in hydrogen with subsequent hydrogenation, disproportionation (HD) under hydrogen pressure of 0.1 MPa and temperatures up to 760°C, and also after desorption, recombination (DR) at temperatures up to 950 °C. The influences of milling on the alloys microstructure were investigated. It was found that NdH2, Fe, Fe2B is formed after HD process. Traces of initial ferromagnetic phase at low hydrogen pressures was identified. Alloys recombination occur in forevacuum at temperatures 840-950°C with the Nd2Fe13,8Zr0,2B grain size equal to 100-220 nm, and 70-140 nm for Nd16Fe73,9Zr2,1B8 after HDDR. The substitution of iron by zirconium leads to increased dispersion of materials after HDDR. Powders are anisotropic. Product Description popup.authors Борух Ігор Володимирович Бурховецький Валерій Вікторович Тростянчин Андрій Миколайович popup.nrat_date 2020-04-02 Close