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چکیده
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The formation mechanism of NiAl-TiC nanocomposite during mechanical alloying of Ni–Ti–Al-C powder mixture was evaluated. The sequence of reactions during milling was obtained by DTA. Also, x-ray analysis was used for phase development, and morphological and microstructural evaluations were carried out by SEM and TEM electron microscopes. The results showed that after 5 h milling, NiAl and TiCxwere formed, and no change in the phase composition was seen by prolongation of milling time to 40 h. The XRD results showed that no reaction took place until 3 h ball milling. DTA analysis of 3 h milled powder showed a broad exothermic peak at temperature range 850 °C–950 °C related to the simultaneous formation of NiAl and TiC. Morphological characterization by TEM confirmed that the final microstructure consisted of NiAl-TiC nanocomposite.
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