Authors: Y.C. Shu
Affilation: California Institute of Technology, United States
Pages: 102 - 105
Keywords: heterogeneous thin films, martensitic materials, multiscale modeling
We propose a multiscale modeling to study the effective behavior of a heterogeneous thin film accounting in detail for the underlying microstructure, grain sizes and the film thickness. Motivated by the recent study of shape-memory thin films, we develop our theory within the framework of 3D nonhomogeneous nonlinear elasticity enhanced with an interfacial energy. We do not require any priori selection of asymptotic expansion or ansatz in deriving our results. Under certain conditions, we show that the behavior of the films can not be predicted solely from that of identical bulk materials and can critically depend on the relative magnitudes of different material length scales. We apply our theory to martensitic materials and show that the shape-memory behavior can crucially depend on the ratios of these length scales. We comment on some novel and unusual properties that multilayer thin films made of shape-memory and elastic materials can display.