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The contemporary demands in different branches of engineering (aerospace, automotive, etc.) require application of new multi-component materials and structural systems. Ceramic Matrix Composite (CMC) materials play important role, particularly, when high mechanical loading and temperature are operating conditions of the structural elements, e.g. thermal barrier coating. In general, due to: different phases co-existence in CMC, a certain amount of an initial porosity, as well as development of local plasticity and internal microdefects during loading, the CMC behaviour becomes highly non-linear and complex. The initial microdefects grow into mesocracks and finally macrocracks, mainly inter-granularly, inducing anisotropic CMC response under loading process. The present paper proposes a unified multiscale approach to modelling of the CMC behaviour at different scales: micro-, meso- and macro-. A capability of the method was presented by numerical examples for two-phase composite made of alumina and zirconia (with different volume contents) and porous alumina subjected to a simple tension process. The multiscale approach is a convenient tool for description of the CMC behaviour comprising gradual degradation, i.e. gradual decreasing of elastic material properties due to microdefects grow. Crown Copyright (C) 2010 Published by Elsevier B.V. All rights reserved.
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