چکیده
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The aim of the present study was to investigate the phases formed during ball milling of Al–TiO2–NiO. For this purpose, a mixture of Al–TiO2–NiO with a molar ratio of 6:1:1 was used. Characterization of the milled powders by X-ray diffraction, differential thermal analysis, field-emission scanning electron microscopy, and transmission electron microscopy showed the formation of nanocrystalline NiTi2 along with AlNi. A thermodynamical investigation confirmed that NiO was reduced by Al during ball milling, which consequently promoted TiO2 reduction and the formation of NiTi2. Al is capable of reducing NiO either during ball milling or at temperatures above the melting point of Al; by contrast, TiO2 can be reduced by Al only by milling.
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