Fatigue Characterization of Piezo-Active Beams in Bending

This paper presents the fatigue characterization of piezo-active beams in bending with surface bonded Macro-Fiber Composite actuators. Three substrate materials are considered: stainless steel, aluminum, and brass. First, the bending response is quantified theoretically using the classical laminate plate theory. The theoretical bending results indicate that the beam with the steel substrate had the largest curvature, and the specimen with the aluminum had the least. Next, midpoint deflection in a simply supported configuration in response to harmonic quasi-static actuation is experimentally measured. The results from the experiments showed no evidence of degradation of actuation for up to four million cycles at the harmonic excitation amplitude of 500 V; however, the results appeared highly sensitive to temperature.