Determination of out-of-plane electrical resistivity for nonoxide ceramic matrix composites

The understanding of the directional dependence of electrical properties in composite materials is essential to develop an accurate electromechanical model for these materials. However, determining the out-of-plane electrical resistivity in composite materials is a challenging task due to the architectural complexity of these materials and the different electrical conductivity of the composite constituents. Moreover, the small thickness of most CMC panels imposes physical difficulties on measuring the out-of-plane electrical resistivity directly. This work provides an indirect method for determining the out-of-plane electrical resistivity for composite materials while introducing the concept of length constant. This method was utilized and successfully verified for three ceramic matrix composite systems with significantly different electrical properties. The proposed method can potentially be employed for other composite systems with conductive phases.