Abstract
We study thermal-physical characteristics of nano-sized amorphous tungsten and of its oxide. It is shown that a nano-size amorphous metal gets into a nano-size crystalline state after heating up to temperatures much lower than the half-temperature of melting, which is typical for all nano-size amorphous materials. Phase transition of amorphous nano-size WO2 into crystalline state occurs in the temperature range 350–520°C, while the same transition in case of W takes place in the range 1000–1370°C. The energy released at crystallization of nano-size amorphous metal amounts to 170±25 J/g coinciding practically with the value of specific melting heat of usual tungsten. Such a high additional energy of nano-size amorphous metals above the energy of nano-size crystalline metals is their main peculiarity which widens essentially the range of their practical applications.
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Original Russian Text © R.T. Malkhasyan, R.V. Arutyunyan, L.V. Kamaeva, E.I. Salamatov, 2014, published in Izvestiya NAN Armenii, Fizika, 2014, Vol. 49, No. 1, pp. 54–61.
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Malkhasyan, R.T., Arutyunyan, R.V., Kamaeva, L.V. et al. Phase transition of nano-sized amorphous tungsten to a crystalline state. J. Contemp. Phys. 49, 34–38 (2014). https://doi.org/10.3103/S106833721401006X
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DOI: https://doi.org/10.3103/S106833721401006X