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Metallography is defined as the science of the constitution and structure (or microstructure) of a metal. During metallographic inspection, the failure analyst or technician, sections the area of interest usually through abrasive‐wheel cutting and mounts the specimen without deformation. The metallographic cross section is then polished to a mirror‐like finish. The sample is subsequently examined by the Metallurgist in a metallurgical microscope.

Many important macroscopic properties of metallic materials are highly sensitive to the microstructure. Critical mechanical properties, like tensile strength or elongation, as well as other thermal or electrical properties, are directly related to the microstructure.

Metallographic examination involves the use of high magnification microscopy. These examinations may include optical and scanning electron microscopy. Optical microscopic examination is used to determine grain size, microstructure, and inclusion type and content. On the other hand, scanning electron microscopy is used to determine abnormalities, such as inclusions, segregation, and surface layers, as well as fracture features.