Measurement of the fracture energy at the interface between porous cathode layer and electrolyte in planar solid oxide fuel cells

The fracture energy at the interface between the porous cathode and the electrolyte of a planar solid oxide fuel cell is determined by a four-point bending test. During the preparation of specimens the resin used to bond the stiffeners completely impregnates the porous cathode. The adhesion of the resin to the electrolyte is measured separately in order to extract a reliable value of the interface fracture energy (20.2 ± 6.7 J m−2). The mode-mixity is found to be equal to 31°.