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 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.

Precious metals are of inestimable value to modern civilization. This article discusses the resources and consumption, trade practices, and special properties of precious metals and its alloys, including ruthenium, rhodium, palladium, silver, osmium, iridium, platinum, and gold, and tabulates the industrial applications of precious metals. It provides information on the commercial forms (wire, rod, sheet, strip, ribbon, and foil) and uses of precious metals, including semifinished products, precious metal powders, industrial uses, coatings, and jewelry.

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.

This article focuses on the use of noble and precious metals for biomedical applications. These include gold, platinum, palladium, ruthenium, rhodium, iridium, and osmium. The physical and mechanical properties of 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. It also provides information on gold coatings and iridium oxide coatings for stents.

The analysis of composite materials using optical microscopy is a process that can be made easy and efficient with only a few contrast methods and preparation techniques. This article is intended to provide information that will help an investigator select the appropriate microscopy technique for the specific analysis objectives with a given composite material. The article opens with a discussion of macrophotography and microscope alignment, and then goes on to describe various illumination techniques that are useful for specific analysis requirements. These techniques include bright-field illumination, dark-field illumination, polarized-light microscopy, interference and contrast microscopy, and fluorescence microscopy. The article also provides a discussion of sample preparation materials such as dyes, etchants, and stains for the analysis of composite materials using optical microscopy.

This article discusses the fundamentals of electroplating processes, including pre-electroplating and surface-preparation processes. It illustrates the four layers of a plating system, namely, top or finish coat, undercoat, strike or flash, and base material layers. The article describes various plating methods, such as pulse electroplating, electroless plating, brush plating, and jet plating. It reviews the types of electrodeposited coatings, including hard coatings and soft coatings. The article also details the materials available for electroplating, including electroplated chromium, electroplated nickel, electroless (autocatalytic) nickel, electroless nickel composite coatings, electroplated gold, and platinum group coatings. These are specifically tailored toward plated coatings for friction, lubrication, and wear technology. The article concludes with a discussion on the common issues encountered with electroplating.

This article focuses on the selection, properties, and applications of powder metallurgy refractory metals and their alloys, including tungsten, molybdenum, tantalum, niobium, and rhenium.

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 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.

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.

Copper, copper alloys, and precious metals are probably the most easily brazed metals because of their resistance to oxidation at high temperatures. This article provides a brief discussion on the metallurgy of copper, copper alloys, and precious metals and discusses the filler metals, brazing fluxes, joint clearance and design, and different brazing processes used in brazing of copper, copper alloys, and precious metals.

This article explains how to prepare precious metal test samples for metallographic examination. It discusses cutting, mounting, grinding, polishing, and etching and addresses some of the challenges of working with small, relatively soft specimens. It includes dozens of example micrographs, comparing and contrasting the microstructural features of gold, platinum, iridium, palladium, and ruthenium-base alloys. It examines pure gold, intermetallic gold compounds, gold and platinum jewelry alloys, platinum-containing shape memory alloys, and alloys consisting of platinum, aluminum, and copper.

Brazing and soldering are done at temperatures below the solidus temperature of the base material but high enough to melt the filler metal and allow the liquid filler metal to wet the surface and spread into the joint gap by capillary action. This article discusses the common advantages of both brazing and soldering. It describes the brazing and soldering of cast irons, as well as the selection of brazing filler material. The article discusses various brazing methods: torch brazing, induction brazing, salt-bath brazing, and furnace brazing. It concludes with information on the application examples of brazing of cast iron.

This article provides information on basic chemical equilibria, wet analytical chemistry, and the appropriateness of classical wet methods. It focuses on nonoxidizing acids and oxidizing acids. The article includes information on the qualitative methods used to identify materials by wet chemical reaction. Gravimetry, in which a chemical species is weighed; titrimetry, which involves volume measurement of a liquid reactant; and a host of separation techniques, which require diverse forms of laboratory manipulation, are discussed. The article briefly describes the partitioning of oxidation states as well as those applications in surface studies and rapid material identification in which chemical techniques have proved useful.

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 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 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.