The surface diffusion of tungsten at very high temperatures
نویسندگان
چکیده
2014 The surface self-diffusion coefficient of tungsten in the region of extreme high temperatures (3 000-3 600 K) is determined from van der Mast experimental data on laser heated tips using our theory on tip evolution by capillarity forces and evaporation. In contrast to previous results at less high temperatures, the new results show a slope change in the Log Ds versus 1/T curve indicating a change of the diffusion mechanism with increasing temperature. LE JOURNAL DE PHYSIQUE LETTRES TOME 39, ler NOVEMBRE 1978, Classification Physics Abstracts 68.40
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