Yielding and strain hardening in metallic thin films on substrates are studied using a simple edge dislocation climb model, modified to mimic dislocation processes in passivated, single crystal FCC metal films with a (111) texture. The aim of the modeling is to produce closed-form solutions for the yield strength and rate of strain hardening that can be compared with experiment. The models give a good account of the dependence of the yield strength of passivated gold films on silicon substrates on the film thickness and they are in broad agreement with the experimental observation that plastic flow in passivated metal films is characterized by very high rates of strain hardening. However, these simple models fail to predict the observed decrease in the rate of strain hardening with increasing film thickness, a result that requires more computationally intensive discrete dislocation modeling.
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