Download or read book Surface Segregation in Multicomponent Systems written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-11 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of surface segregation, although of great technological importance, has been largely restricted to experimental work due to limitations associated with theoretical methods. However, recent improvements in both first-particle and semi-empirical methods are opening, the doors to an array of new possibilities for surface scientists. We apply one of these techniques, the Bozzolo, Ferrante and Smith (BFS) method for alloys, which is particularly suitable for complex systems, to several aspects of the computational modeling of surfaces and segregation, including alloy surface segregation, structure and composition of alloy surfaces, and the formation of surface alloys. We conclude with the study of complex NiAl-based binary, ternary and quaternary thin films (with Ti, Cr and Cu additions to NiAl). Differences and similarities between bulk and surface compositions are discussed, illustrated by the results of Monte Carlo simulations. For some binary and ternary cases, the theoretical predictions are compared to experimental results, highlighting the accuracy and value of this developing theoretical tool.Bozzolo, Guillermo and Ferrante, John and Noebe, Ronald D. and Good, Brian and Honecy, Frank S. and Abel, PhillipGlenn Research CenterMETAL SURFACES; THIN FILMS; SURFACE STABILITY; ALLOYS; SEPARATION; MONTE CARLO METHOD; NICKEL ALUMINIDES