Electrically Based Non-Destructive Microstructural Characterization of All Classes of Materials

Abstract

ABSTRACTThis paper gives a short summary of the background, theory and methodology needed to utilize electrical measurements as a non-destructive method for microstructural characterization. Examples are given for all classes of materials. Details are given for how to detect: (1) pore volume in thermal barrier coatings, (2) formation of surface layers due to moisture adsorption in a wide variety of materials, (3) orientation of fibers and whiskers in ceramic matrix and polymer matrix composites, (4) crack detection in metals and (5 ) stacking faults in semiconductors. Many other examples are mentioned. It needs to be emphasized that electrical measurements alone are not sufficient to identify the microstructural features of interest but must always be accompanied by complementary techniques. Proper data collection and data interpretation of properties of a specific set of materials can lead to in-line process monitoring, quality control monitoring, mechanical damage monitoring and environmental degradation monitoring of those materials.