Lifetime and Reliability in Pb(Mg,Nb)O3–Pb(Zr,Ti)O3 Multilayer Ceramic Actuators

Abstract

Lifetime and reliability of multiplayer ceramic actuators were estimated. 5×5×5 mm3 sized multilayer ceramic actuators with 50 ceramic sheet layers embedded internal electrodes were selected in these experiments. Specially selected rectified AC bias was applied to the multilayer ceramic actuators to remove heating from charging and discharging processes. 16 sets of multilayer ceramic actuators were tested for statistical analysis. Weibull function method was employed for statistical analysis. Arrhenius model and power law model were considered to simulate experimental data. From the SEM analysis in destroyed device, crack growth of multilayer ceramic actuator was clearly observed along to the boundary between electrode and inactive region. The main reason for destruction of multilayer ceramic actuators was mechanical tensile stress come from both actuation of d33 mode and motion of Poisson ratio.