Published online by Cambridge University Press: 31 January 2011
The effects of internal electrodes on the fracture properties of relaxor ferroelectric 0.9Pb(Mg1/3Nb2/3)O3–0.1PbTiO3 multilayer structures were studied. It was observed that the position of the first electrode layer from the surface is critical to the strength and toughness of the multilayer structure. Positioning the electrode close to the surface was found to enhance interaction with cracks which initiate on the multilayer surface. This interaction limits the effective crack length and therefore increases the fracture strength and effective toughness of the composite. Samples indented parallel to the electrodes exhibited higher fracture strengths and toughness than those indented perpendicular to the conducting layers. Both parallel and perpendicular orientations gave higher strength and toughness than the control specimens (without electrodes).