Crack propagation analysis in multilayer piezoelectric energy harvester

Abstract In this work, a special multilayer piezoelectric cantilever energy harvester with active piezo-electric and protective ceramic layers was suggested and studied. Fracture mechanics behavior of such a layered structure was analyzed by means of the analytical model. Namely, the resistance of the structure to propagation of surface cracks upon harmonic vibrations was studied. The apparent fracture toughness of the laminate (taking into account also thermal residual stresses induced from processing) was calculated using the weight function method. The maximal allowable acceleration of the beam´s clamped end applied upon the given forcing frequency and warranting that the potential surface cracks will not propagate through the multilayer structure was determined for a suggested configuration of the energy harvester.