A finite element-based numerical model is developed to characterize the effects of fiber distribution in 1-3 piezoelectric active fiber/active matrix composites under primarily static electric fields and elastic stress conditions. Upon identifying 14 characteristic periodic and randomized fiber configurations, the influence of fiber distribution on the coupled response of model ceramic-matrix and polymer-matrix fiber composites with widely different constituent material properties is examined. It is demonstrated that: (i) while certain fiber arrangements provide a higher packing density than others, the fundamental elastic, dielectric and piezoelectric material constants of the 1-3 piezoelectric composites remain largely insensitive to the nature of (periodic or randomized) fiber distributions in the matrix; (ii) the piezoelectric figures of merit of the composite are also invariant to differences in fiber distribution; and (iii) the distribution of internal stresses in the piezoelectric composites in response to mechanical loads tend to be modulated by the nature of the fiber configuration, with the square edge and randomized fiber distributions providing reduced levels of interfacial stresses. (c) 2006 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
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