Micromechanicalfiniteelementmethodsaredevelopedbasedonanonlinearconstitutivemodelofferroelectricpolycrystals.Electromechanicalbehaviorsaheadofaninternalelectrodetiparenumericallysimulatedinmultilayerferroelectricactuators.Aroundtheelectrodeedge,thenonuniformelectricfieldgeneratesaconcentrationofstressduetotheincompatiblestrainaswellasspontaneousstrain.Thepreferreddomainswitchingenhancestheconcentrationofresidualstressandmaycausetheactuatorstocrack.Anelectricallypermeablecrackemanatingfromaninternalelectrodeisanalyzed.Alargescaledomainswitchingzoneisfoundinthevicinityofcracktips.Thelargertheactuatingstrainandelectricfieldare,thelargertheswitchingzonewillbe.Thesizeofswitchingzoneevenreachesthescaleofcracklengthwithincreasingelectromechanicalloading.
