“Phase-field crystal study of compositional domain formation on surfaces”

BROWN UNIVERSITY
Joint Materials/Solid Mechanics Seminar Series

“Phase-field crystal study of compositional domain formation on surfaces”

Prof. Mikko P. Haataja
Department of Mechanical and Aerospace Engineering
Princeton University

Abstract:

When deposited on a surface, bulk-immiscible binary alloys often display interesting compositional domain formation phenomena at the atomic scale, driven by the lattice mismatch between the substrate atoms and the alloy constituents. Control of such nanoscale features may offer a means to engineer surfaces with tunable chemical and mechanical properties. In this work, we study the structure and dynamics of such domains using the so-called phase-field crystal (PFC) method. In the limit of purely elastic deformations of the adlayer, the model predicts the formation of compositional nanoscale domains for a 1:1 mixture, in agreement with experiments and previous simulations. We further examine the interplay between misfit dislocation formation and compositional patterning for a wide range of alloy compositions.

Monday, April 12, 2010 4:00-5:00 pm B&H Room 190