L'influence de la taille des grains sur la fracture par écaillage du cuivre soumis à une charge explosive est étudiée. On trouve que la contrainte d'écaillage dépend de la taille des grains. La transition fracture intergranulaire-fracture transgranulaire est étudiée en détail. La simulation numérique des expériences est réalisée. The influence of grain size on the spall fracture of copper under explosive loading was studied. It was found that samples with different grain sizes exhibited different spall strength. The fracture mode transition from intergranular to transgranular fracture was studied in details. The numerical simulation of explosive experiments were performed.

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The lifetime of three types of AMTEC electrodes is predicted from the rate of grain growth in the electrode. Grain size is related to electrode performance, allowing performance to be correlated with grain growth rate. The rate of growth depends on physical characteristics of each material, including the rates of surface self-difhsion and molecule mobility along grain boundaries. Grain growth rates for molybdenum, rhodium-tungsten and titanium nitride electrodes have been determined experimentally and fit to models in order to predict operating lifetimes of AMTEC electrodes. For lifetimes of 10 years or more, Rh,W electrodes may be used at any operating temperature supportable by the electrolyte. TiN electrodes may be used in AMTEC cells only at operating temperatures under 1150 K. and Mo may be used only below 1100 K.

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