Metallography and Microscopy

This chapter includes metallographic techniques, followed by microscopy such as traditional optical microscope (OM) or light microscope (LM), scanning electron microscope (SEM), transmission electron microscope (TEM), and the like. Metallography is essentially a metallurgical technique used to mechanically prepare a specimen with a flat and mirrorlike surface, which in turn is etched or chemically oxidized to reveal the surface microstructure. Hence, metallographic analysis and microscopy are used as tools to examine single and multiple phases within metallurgical specimens. For comparison, metallography is used to reveal microstructural features and fractography for assessing fractured surfaces. In particular, black-and-white (B&W) or color metallography involves simple and sophisticated equipment for obtaining high-quality microstructures through the lens of science. The main goal in the microscopy field is to reveal microstructural features, such as grain shape, inclusions, small secondary particles, and linear defects called dislocations. Regarding microscopic size particles, stereology provides means to perform quantitative metallography, and the American Society for Testing Materials (ASTM) recommends a comparative method for the grain size number.