The electroplating of platinum-group metals (PGMs) from aqueous electrolytes for engineering applications is limited principally to palladium and, to a lesser extent, to platinum, rhodium, and thin layers of ruthenium. This article provides a discussion on the plating operations of these PGMs along with the types of anodes used in the process.

Precious metals include gold, silver, and six platinum-group metals, namely, platinum, palladium, ruthenium, rhodium, osmium, and iridium. This article focuses on the consumption, trade practices, properties, product forms, and applications of these metals and their alloys.

This article focuses on the use of noble and precious metals for biomedical applications. The noble metals include gold, platinum, palladium, ruthenium, rhodium, iridium, and osmium. The physical and mechanical properties of the noble and precious metals are presented in tables. A brief discussion on the ancient history of noble and precious metal use in dentistry is provided. The article discusses the use of direct gold dental filling materials, direct silver dental filling materials, traditional amalgam alloys, high-copper amalgam alloys, and gallium alloys in biomedical applications. Modern stents were developed as a result of balloon catheterization research. The article describes gold coatings and iridium oxide coatings for stents.

This article characterizes the corrosion resistance of precious metals, namely, ruthenium, rhodium, palladium, silver, osmium, iridium, platinum, and gold. It provides a discussion on the general fabricability; atomic, structural, physical, and mechanical properties; oxidation and corrosion resistance; and corrosion applications of these precious metals. The article also tabulates the corrosion rates of these precious metals in corrosive environment, namely, acids, salts, and halogens.

This article addresses surface cleaning, finishing, and coating operations that have proven to be effective for molybdenum, tungsten, tantalum, and niobium. It describes standard procedures for abrasive blasting, molten caustic processing, acid cleaning, pickling, and solvent and electrolytic cleaning as well as mechanical grinding and finishing. The article also provides information on common plating and coating methods, including electroplating, anodizing, and oxidation-resistant coatings.

This article discusses various concepts of micro x-ray diffraction (XRD) used for the examination of materials in situ. The discussion covers the principles, equipment used, sample preparation procedure, considerations for calibrating a detector, steps for performing data analysis, and applications and interpretation of micro-XRD.

The refractory metals include niobium, tantalum, molybdenum, tungsten, and rhenium. They are readily degraded by oxidizing environments at moderately low temperatures. Protective coating systems have been developed, mostly for niobium alloys, to permit their use in high-temperature oxidizing aerospace applications. This article discusses the properties, processing, applications, and classes of refractory metals and its alloys, namely molybdenum, tungsten, niobium, tantalum and rhenium. It also provides an outline of the coating processes used to improve their oxidation resistance.

This article focuses on the recycling of metals including iron and steel, stainless steel, superalloys, nickel, aluminum, copper, precious metals, lead, magnesium, tin, titanium, and zinc. It provides information on the identification and sorting of scrap metals and discusses the equipment and procedures used for small-scale and large-scale scrapping operations.

Material properties are the link between the basic structure and composition of the material and the service performance of a part or component. This article describes the most significant properties that must be considered when choosing a metal for a given application, namely physical properties (mass characteristics and thermal, electrical, magnetic, radiation, and optical properties), chemical properties (corrosion and oxidation resistance) and mechanical properties (tensile and yield strength, elongation, toughness, hardness, creep, and fatigue). The article also contains tables that list room-temperature physical properties, vapor pressures, and mechanical properties for various metals.

This article describes the methods and equipments involved in the preparation of specimens for examination by light optical microscopy, scanning electron microscopy, electron microprobe analysis for microindentation hardness testing, and for quantification of microstructural parameters, either manually or by the use of image analyzers. Preparation of metallographic specimens generally requires five major operations: sectioning, mounting, grinding, chemical polishing, and etching. The article provides information on the principles of technique selection in mechanical polishing, and describes the procedures, advantages, and disadvantages of electrolytic and chemical polishing. It also provides a detailed account of procedures, precautions, and composition for preparation and handling of etchants.

This article provides a detailed account on forming operations (blanking, piercing, press-brake forming, contour rolling, deep drawing, cold forming, and hot forming) of various nonferrous metals, including aluminum alloys, beryllium, copper and its alloys, magnesium alloys, nickel alloys, titanium alloys, and platinum metals. It discusses the formability, equipment and tooling, and lubricants used in the forming operations of these nonferrous metals.

This article contains tables that present engineering data for the following metals and their alloys: aluminum, copper, iron, lead, magnesium, nickel, tin, titanium, zinc, precious metals, permanent magnet materials, pure metals, rare earth metals, and actinide metals. Data presented include density, linear thermal expansion, thermal conductivity, electrical conductivity, resistivity, and approximate melting temperature. The tables also present approximate equivalent hardness numbers for austenitic steels, nonaustenitic steels, austenitic stainless steel sheet, wrought aluminum products, wrought copper, and cartridge brass. The article lists conversion factors classified according to the quantity/property of interest.

Vacuum heat treating consists of thermally treating metals and alloys in cylindrical steel chambers that have been pumped down to less than normal atmospheric pressure. This article provides a detailed account of the operations and designs of vacuum furnaces, discussing their pressure levels, resistance heating elements, quenching systems, work load support, pumping systems, and temperature control systems. It describes the classification of instruments used for measuring and recording pressure inside a vacuum processing chamber. Common devices include hydrostatic measuring devices and devices for measuring thermal and electrical conductivity. The article also describes the applications of the vacuum heat treating process, namely, vacuum nitriding and vacuum carburizing. Finally, it reviews the heat treating process of tool steels, stainless steels, Inconel 718, and titanium and its alloys.

The selection of engineered materials is an integrated process that requires an understanding of the interaction between materials properties, manufacturing characteristics, design considerations, and the total life cycle of the product. This article classifies various engineered materials, including ferrous alloys, nonferrous alloys, ceramics, cermets and cemented carbides, engineering plastics, polymer-matrix composites, metal-matrix composites, ceramic-matrix and carbon-carbon composites, and reviews their general property characteristics and applications. It describes the synergy between the elements of the materials selection process and presents a general comparison of material properties. Finally, the article provides a short note on computer aided materials selection systems, which help in proper archiving of materials selection decisions for future reference.