FINITE-ELEMENT MODELING OF LEAD MAGNESIUM NIOBATE ELECTROSTRICTIVE MATERIALS - STATIC ANALYSIS

New lead magnesium niobate (PMN) ceramics, which can generate large st rains at moderate electric fields, are good candidates for future actu ators or sonar projectors. In this paper, two finite element models ar e proposed to describe static analysis of electrostrictive materials. Both models include quadratic dependence of strain with electrical dis placement, assume constant temperature, and exclude hysteresis. One of the models includes the saturation of the polarization. The theoretic al formulation is justified by the method of the weighted residuals. T he numerical implementation is presented. The validation is performed by comparing numerical results with measurements for a PMN bar subject ed to mechanical prestress and de electric field. (C) 1998 Acoustical Society of America.