Тип публикации: статья из журнала
Год издания: 2010
Идентификатор DOI: 10.1016/j.matlet.2010.04.017
Ключевые слова: order-disorder transition, point defects, Ti3Al thin-films
Аннотация: A statistical-thermodynamic modeling based on Ising approach and Bethe-Bragg-Williams approximations is proposed for description of ordering phenomena and thermodynamic behavior in nano-crystalline thin-film materials with D019-structure. New modeling approach takes into account presence of all possible defects in the structure, boПоказать полностьюth vacancies and anti-structure atoms and includes a description of long-range and short-range ordering in the crystal lattice. The derived equations define the fluctuations of internal variables, such as pair interaction energies between atoms and defects and their contributions to macroscopic properties. The variation of defect concentrations, ordering tendency, and thermodynamic activities as a function of number of monoatomic layers, temperature and composition are derived. The obtained theoretical results are tested using experimental data on thermodynamic activity for bulk intermetallic phase such a Ti3Al. It was shown that the bulk behavior in nano-Ti3Al is approached with a thickness of about 100 layers. © 2010 Elsevier B.V. All rights reserved.
Журнал: Materials Letters
Выпуск журнала: Т. 64, № 14
Номера страниц: 1641-1643
ISSN журнала: 0167577X
Издатель: Elsevier Science Publishing Company, Inc.