Thermal Shape Control of Active and Sensory Piezoelectric Composite Plates

Previously developed mechanics for piezoelectric composite materials are extended to account for thermal effects. The updated mechanics accounts for thermal effects which arise due to: (1) coefficient of thermal expansion mismatch between the various composite and piezoelectric layers, (2) pyroelectric effects on the piezoelectric plies, and (3) the temperature dependence of the composite and piezoelectric properties. The coupled mechanical, electrical, and thermal response of piezoelectric composite materials is captured at the material level. A layerwise laminate theory is formulated with the inherent capability to model both the active and sensory response of piezoelectric composite materials. Finite element equations are developed and implemented for a bilinear plate element. Numerical studies are conducted on a simply supported graphite/epoxy plate with attached piezoceramic patches to investigate thermal shape control applications and to study the resultant stress state.