The effective magnetoelectroelastic moduli of matrix-based multiferroic composites

In this paper, we develop a mean field Mori-Tanaka model [T. Mori and K. Tanaka, Acta. Metall. 21, 571 (1973)] to calculate the effective magnetoelectroelastic moduli of matrix-based multiferroic composites, emphasizing the effects of shape and orientation distribution of second phase particles that have not been investigated before. Through a systematic study, it is observed that laminated composites are optimal for magnetoelectric coefficient a11, while fibrous composites are optimal for a33. In addition, these coupling coefficients are maximum when the second phase particles are aligned. It is also postulated that the large discrepancy between theoretical predictions and experimental measurements for magnetoelectric coefficients of multiferroic composites previously reported is partly due to the orientation distribution of second phase particles, which has not been considered before in theoretical modeling. When our calculations take the orientation distribution of second phase particles into account with appropriate texture coefficient, good agreement with experimental data is observed.