Metallography/Microstructure Evaluation

The properties of a material and its performance in a specific application depends on its microstructure.  Our metallographs (light microscopes) are capable of examinations at magnifications from 15X to 1,000X.  Analyses of microstructure and material defects in cross-sectioned samples determine material properties, flaw characteristics, and defect mechanisms. 

Metallurgical Technologies, Inc. (MTi) has full metallographic preparation capabilities from sectioning and mounting the specimen through the grinding and polishing stages to proper selection and etching techniques of the tested material. 

View of intergranular stress corrosion cracking (IGSCC) in an Inconel heat exchanger tube.  Note that the crack follows the grain boundaries. (Mag: 500X)

View of chloride stress corrosion cracking in a 316 stainless steel chemical processing piping system.  Chloride stress corrosion cracking in austenitic stainless steel is characterized by the multi-branched "lightning bolt" transgranular crack pattern. (Mag: 300X)

Microstructure evaluation of the heat-affected zone of a welded stainless steel piping flange etched to reveal the carbide distribution.  Fine carbide particles outline the grain boundaries, indicating a "sensitized" condition resulting in susceptibility to intergranular corrosion. (Mag:  600X)

	A cross-section through a seam weld in a 400 series ferritic stainless steel tube.  The seam exhibits a wide fusion zone and a large grain size contributing to brittleness of the weldment. (Mag: 25X)
Our metallurgical engineers also evaluate microstructure to determine root cause of failure. For more information, please visit our Failure Analysis page.