%0 Journal Article %A Zhang, Zhaohui %A Zhuang, Zhuo %A You, X. C. %A Liu, Z. L. %A Nie, J. F. %A Gao, Yuan %D 2013 %I Begell House %K thin film, multiscale micromorphic, size effect, Bauschinger effect, grain boundary densitya %N 1 %P 45-57 %R 10.1615/IntJMultCompEng.2012003172 %T MULTISCALE MICROMORPHIC MODEL FOR THE PLASTIC RESPONSE OF CU THIN FILM %U https://www.dl.begellhouse.com/journals/61fd1b191cf7e96f,4e088eb4220ee69a,27be1c0c31e9184e.html %V 11 %X In this article, the multiscale micromorphic plasticity model is employed to quantitatively investigate the size and Bauschinger effects of freestanding Cu thin films in a continuum sense. The simulations, including the single-layer and multi-layer models, are carried out within a two-dimensional plane strain framework with the passivation layer modeled as the higher-order boundary condition. The computational results are compared with the experimental data of two sets of films consisting of the electroplated and sputtered films. It is found that for the electroplated films, the effects of film thickness are in quite good consistent with the experimental data. The strengthening factor charactering the passivation effect agrees well with the experiments for both the electroplated and sputtered films. The boundary layers near the internal interfaces (grain boundaries or film-passivation layers) are captured. The accumulation of the backstress scales almost linearly with the pre-strain. In the multi-layer polycrystal model, the yield strength of electroplated films obeys a nonlinear dependence on grain boundary density. %8 2013-02-08