(IMS) Characterization of Materials and Microstructure through Metallography, Image Analysis, and Mechanical Testing - Fundamental and Applied Studies

Dislocations were extensively studied in metals as transmission electron microscopy (TEM) became established as a critical experimental technique for studying the structure and defects in metals, and this was later extended to ceramics and semiconductors (many of which are themselves ceramics). What TEM could not do so well until much later was the combine chemical information with the structural studies, which is not unconnected with the fact that ‘defects’ automatically referred to ‘larger than atoms’. Now the TEM can address the full spectrum of ‘defects’ and even investigate defects on these defects, like jogs on dislocations, disconnections on grain boundaries, and triple junctions on any interface structure. Perhaps these features (dislocations), which relate primarily to mechanical properties, but generally to any situation where defects impact the properties of the material, are not studied extensively because the ‘relevance’ is not clear or the teaching is not so exciting. Of course, dislocations are critical to understanding the properties of materials but the study and teaching may be less attractive to students. This talk will discuss the challenges faced by teachers and researchers, and the role of TEM. The title is a reference to a chapter in the textbook Ceramic Materials.