The metallographic specimen preparation process for microstructural investigations of cast iron specimens usually consists of five stages: sampling, cold or hot mounting, grinding, polishing, and etching with a suitable etchant to reveal the microstructure. This article describes the general preparation of metallographic specimens and the methods of macroscopic and microscopic examination. Usually, gray-scale (black-and-white) metallography is sufficient for microstructural analysis of cast irons. The article discusses the use of color metallography of gray irons and ductile irons. It also presents application examples of color metallography.

This article begins with a description of indirect and direct semisolid metalworking processes. It then provides information on alloy compositions of common aluminum semisolid metalworking alloys and primary die-cast magnesium alloys in a tabular form. The article describes the macroscopic examination of defects, which occur in semisolid metalworking with illustrations. It discusses the macroscopic examination of gating systems and semisolid feedstocks. The article also provides information on feedstock microstructures, direct semisolid metalworking component microstructures, and indirect semisolid metalworking component microstructures of series 300 aluminum casting alloys and magnesium die-casting alloys.

This article describes the microstructure of copper alloys, including copper-zinc (brasses), bronzes, copper-nickel, and copper-nickel-zinc, and examines the effect of oxygen content on alloy phases observed in different product forms. The article also discusses inclusions, etchants, and the effect of composition and processing on grain structure and growth rates.

This article discusses the principles of physical metallurgy and metallography of depleted uranium. It describes the techniques involved in the preparation of thin foils for transmission electron microscopy and illustrates the resulting microstructure of uranium and uranium alloys, with the aid of black and white images. The article also provides information on the applications of etching and examination of uranium alloys, at both macro and micro scales, in characterizing the grain structures, segregation patterns, inclusions, and the metal flow geometries produced by solidification and mechanical working processes.

This article provides an overview of the origin of metallography. It presents information on how to select a section from a specimen and prepare it for macroscopic analysis. The article describes the macroscopic analysis of steel fracture surfaces with emphasis on ductile, brittle, and fatigue fracture with illustrations. It discusses microanalysis with a focus on the method of light microscopy and includes information of scanning electron microscope in fractography. The article also explains the characteristics of solidification, transformation, deformation structures, and discontinuities that are present in a microstructure. It concludes with information on image analysis.

Magnesium and its alloys are among the most difficult metals to prepare for metallographic examination. This article describes specimen preparation processes, including sectioning, mounting, grinding, and polishing. It discusses macro and microexamination techniques as well as related etching processes, including macroetching and color etching based on polarized light enhancement. The article concludes with an overview of the effects of alloying elements, including aluminum, beryllium, calcium, copper, iron, lithium, manganese, rare earth metals, silicon, silver, strontium, thorium, tin, zinc, and zirconium.

Tool steels are prepared for metallographic examination in the same way as carbon steels with a few variations owing to hardness and alloying differences. This article explains what makes tool steels different and how to compensate for it when sectioning, mounting, grinding, polishing, and etching. It provides information and data on composition, hot working, austenitizing, tempering, and powder metal manufacturing and explains how it affects tool steel microstructure, using more than 100 detailed images.

This article describes metallographic preparation and examination techniques for stainless steels and maraging steels. It presents a series of micrographs demonstrating microstructural features of these alloys. Procedures used to prepare stainless steels for macroscopic and microscopic examination are similar to those used for carbon, alloy, and tool steels. Cutting and grinding must be carefully executed to minimize deformation because the austenitic grades work harden readily. The high-hardness martensitic grades that contain substantial undissolved chromium carbide are difficult to polish while fully retaining the carbides. Unlike carbon, alloy, and tool steels, etching techniques are more difficult due to the high corrosion resistance of stainless steels and the various second phases that may be encountered. The microstructures of stainless steels can be quite complex. Matrix structures vary according to the type of steel, such as ferritic, austenitic, martensitic, precipitation hardenable, or duplex.

This article focuses on the specimen preparation procedures of austenitic manganese steels: sectioning, mounting, and grinding. It provides information on macroexamination and microexamination of a fracture surface, the microstructure and special features of austenitic manganese steels, and the alloying elements used.

This article describes the fundamentals of titanium metallographic sample preparation. Representative micrographs are presented for each class of titanium alloys, including unalloyed titanium, alpha alloys, alpha-beta alloys, and beta titanium alloys. The article provides information on the macroexamination and microexamination for these alloys. It concludes with a discussion on the several metallographic techniques developed for specific purposes, such as recrystallization studies and microstructure/fracture topography correlations.

Lightning damage in polymer composites is manifested by damage at both the macroscopic or visual level and within the material microstructure. This article illustrates the effects of the laboratory-generated lightning strikes on polymeric composites.

This article describes the microstructure and metallographic practices used for medium- to high-carbon steels as well as for low-alloy steels. It explains the microstructural constituents of plain carbon and low-alloy steels, including ferrite, pearlite, and cementite. The article provides information on how to reveal the various constituents using proven metallographic procedures for both macrostructural and microstructural examination. Emphasis is placed on the specimen preparation procedures such as sectioning, mounting, grinding, and polishing. The article illustrates the use of proven etching techniques for plain carbon and low-alloy steels.

This article provides information on the microstructure of powder metal alloys and the special handling requirements of porous materials. It covers selection, sectioning, mounting, grinding, and polishing, and describes procedures, such as washing, liquid removal, and impregnation, meant to preserve pore structures and keep them open for analysis. The article compares and contrasts the microstructures of nearly 50 powder metal alloys, using them to illustrate the effect of consolidation and compaction methods as well as particle size, composition, and shape. It discusses imaging equipment and techniques and provides data on etchants and etching procedures.

This article focuses on the metallography and microstructures of wrought and cast aluminum and aluminum alloys. It describes the role of major alloying elements and their effect on phase formation and the morphologies of constituents formed by liquid-solid and/or solid-state transformations. The article also describes specimen preparation procedures and examines the microstructure of several alloy samples.

The two major types of beryllium-containing alloys are copper-berylliums and nickel-berylliums. The most widely used beryllium-containing alloys are wrought copper-berylliums, which provide good strength while retaining useful levels of electrical and thermal conductivity. This article provides information on the specimen preparation procedures, macroexamination, microexamination, and microstructures of beryllium, copper-beryllium alloys, as well as nickel-beryllium alloys. It also discusses health and safety measures associated with the specimen preparation of beryllium and beryllium-containing alloys.

This article focuses on the visual or macroscopic examination of damaged materials and interpretation of damage and fracture features. Analytical tools available for evaluations of corrosion and wear damage features include energy dispersive spectroscopy, electron probe microanalysis, Auger electron spectroscopy, secondary ion mass spectroscopy, and X-ray powder diffraction. The article discusses the analysis and interpretation of base material composition and microstructures. Preparation and examination of metallographic specimens in failure analysis are also discussed. The article concludes with a review of the evaluation of polymers and ceramic materials in failure analysis.

This article describes the preliminary stages and general procedures, techniques, and precautions employed in the investigation and analysis of metallurgical failures that occur in service. The most common causes of failure characteristics are described for fracture, corrosion, and wear failures. The article provides information on the synthesis and interpretation of results from the investigation. Finally, it presents key guidelines for conducting a failure analysis.

This article commences with a discussion on the characteristics of stress-corrosion cracking (SCC) and describes crack initiation and propagation during SCC. It reviews the various mechanisms of SCC and addresses electrochemical and stress-sorption theories. The article explains the SCC, which occurs due to welding, metalworking process, and stress concentration, including options for investigation and corrective measures. It describes the sources of stresses in service and the effect of composition and metal structure on the susceptibility of SCC. The article provides information on specific ions and substances, service environments, and preservice environments responsible for SCC. It details the analysis of SCC failures, which include on-site examination, sampling, observation of fracture surface characteristics, macroscopic examination, microscopic examination, chemical analysis, metallographic analysis, and simulated-service tests. It provides case studies for the analysis of SCC service failures and their occurrence in steels, stainless steels, and commercial alloys of aluminum, copper, magnesium, and titanium.

This article commences with a summary of fatigue processes and mechanisms. It focuses on fractography of fatigue. Characteristic fatigue fracture features that can be discerned visually or under low magnification are described. Typical microscopic features observed on structural metals are presented subsequently, followed by a brief discussion of fatigue in nonmetals. The article reviews the various macroscopic and microscopic features to characterize the history and growth rate of fatigue in metals. It concludes with a description of fatigue of polymers and composites.

This article describes various evaluation techniques of fractography such as visual inspection, macroscopic and microscopic examinations that are used to resolve different aspects of failure. It gives a brief description and pictorial representation of various defects leading to fracture of metals, including laps, seams, cold shuts, cracks, inclusions, porosity, fatigue, and stress corrosion cracking.