Aa. Bent et Nw. Hagood, PIEZOELECTRIC FIBER COMPOSITES WITH INTERDIGITATED ELECTRODES, Journal of intelligent material systems and structures, 8(11), 1997, pp. 903-919
Piezoelectric Fiber Composites were previously introduced as an altern
ative to monolithic piezoceramic wafers for structural actuation appli
cations. This manuscript. was an investigation into the improvement of
piezoelectric fiber composite performance through a nonconventional e
lectroding scheme. Two microelectromechanical models were developed th
at predict the composite properties. These models were used to examine
the trends of composite properties versus fiber volume fraction for v
arious constituent materials. Several etched electrode PZT fiber compo
sites, with fiber volume fractions ranging from 7% to 58%, were manufa
ctured and tested. Experimental measurements showed excellent agreemen
t with both the trends and magnitude of model predicted values. The ma
ximum fiber volume fraction composites demonstrated a capacitance (eps
ilon(33)(T)/epsilon(0)) Of 550, piezoelectric free strain constants (d
(33) and d(31)) Of 150 pm/V and -70 pm/V, and piezoelectric clamped st
ress (e(33)) of 5 C/m(2), showing a substantial improvement over previ
ous piezoelectric fiber composites with uniform electrodes. Maximum st
rain values of 1700 ppm were measured, indicating higher in-plane actu
ation than monolithic piezoceramics.