Decreasing the grain boundary diffusivity in binary alloys with increasing temperature.
نویسندگان
چکیده
An interfacial thermodynamic model predicts that the interplay of grain boundary (GB) premelting, prewetting, and retrograde solubility in a binary alloy can lead to a decrease in the GB diffusivity with increasing temperature. This counterintuitive prediction is experimentally confirmed for a single-phase, Mo +0.5 at. % Ni alloy. This study calls for a reappraisal of the classical GB adsorption (segregation) theories to consider the coupling with structural disordering, and it critically supports GB premelting and prewetting theories with broad applications.
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ورودعنوان ژورنال:
- Physical review letters
دوره 105 23 شماره
صفحات -
تاریخ انتشار 2010