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Scanning electron microscopy (SEM) has shown various significant improvements since it first became available in 1965. These improvements include enhanced resolution, dependability, ease of operation, and reduction in size and cost. This article provides a detailed account of the instrumentation and principles of SEM, broadly explaining its capabilities in resolution and depth of field imaging. It describes three additional functions of SEM, including the use of channeling patterns to evaluate the crystallographic orientation of micron-sized regions; use of backscattered detectors to reveal grain boundaries on unetched samples and domain boundaries in ferromagnetic alloys; and the use of voltage contrast, electron beam-induced currents, and cathodoluminescence for the characterization and failure analysis of semiconductor devices. The article compares the features of SEM with that of scanning Auger microscopes, and lists the applications and limitations of SEM.

This article presents a brief history of additive manufacturing (AM). It begins by describing additive manufacturing prehistory, dating back to 1860, which is characterized by additive part creation without the use of a computer. The article then discusses the development of additive manufacturing processes occurring in the period from 1968 to 1984 and is followed by a section on modern additive manufacturing (1981 to the late 2000s). The article concludes by providing information on the growth of additive manufacturing since 2010 and the development of standards.

This article describes manufacturing procedures that produce aluminum foams and have since become industrially important and successful. It discusses the foaming of melts by blowing agents and foaming of melts by gas injection. The article focuses on aluminum foams based on the Foaminal technology, because those foams dominate the technical applications of aluminum foams. It also discusses the mechanical properties of metal foams, such as general compression behavior, elastic behavior, strain-rate sensitivity, tensile behavior, ductility, fatigue, and mechanical damping. The article concludes with information on the applications of highly porous metal structures.

Friction welding is based on the rapid introduction of heat, causing the temperature at the interface to rise sharply and leading to local softening. This article illustrates the basic principles of direct-drive rotational friction welding and inertia friction welding. Modeling the effective friction response of the materials is central to simulating the welding process. The article discusses a series of distinct frictional stages during continuous drive friction welding. Modeling of the evolution of the thermal field has been an important objective since the early days of rotational friction welding. The article describes analytical thermal models and numerical thermal models for rotational friction welding. It concludes with information on the modeling of residual stresses.

The prepreg hand lay-up process is a versatile, reliable, cost-effective, and high quality process for fabricating large or small components. This article discusses the technique characteristics and applications of the process. It describes the stages involved in the process of lay-up, namely, lay-up definition, ply-kit cutting, layup, debulking, and preparation for curing. The article concludes with a discussion on the component properties and design guidelines of the prepreg hand lay-up process.

This article describes the characteristics of thermoplastic composites and its material forms. It presents the steps and considerations in manufacturing the thermoplastic composites. The article describes the various techniques of manufacturing, such as consolidation, autoclave molding, diaphragm forming, compression molding, roll forming, bladder molding, liquid molding, filament winding, and pultrusion.

This article provides a detailed discussion on the various devices by which cathodic protection (CP) can be applied to pipe-type power transmission cables. These devices include the resistor rectifier, isolator-surge protector, polarization cells, and field rectifiers. The article describes the interference created by stray currents on CP and associated remedial actions.