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.

The additive manufacturing technologies in the casting of precious metals are divided into two groups: indirect metal methods and direct metal methods. Besides providing a process overview of both of these methods, the focus of this article is on the characteristics, process steps, applications, and advantages of direct metal methods, namely laser melting, material extrusion, binder jetting, material jetting, and vat photopolymerization methods.

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.

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 describes the annealing behavior of precious metals, namely, gold, silver, platinum, palladium, iridium, rhodium, ruthenium, and osmium. It discusses the annealing practices and their effect on the basic properties of common precious metal alloys. The article presents the typical properties and compositions of silver-copper alloys and gold jewelry alloys such as colored gold alloys and white gold alloys.

This article discusses the chemical composition, fabrication characteristics, applications, mechanical properties, mass characteristics, thermal properties, electrical properties, optical properties, and chemical properties of precious metals, namely, silver, gold, platinum, and palladium and their corresponding alloys.

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 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.

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.

This article describes the principal cladding processes and methods for calculating properties of clad metals. It reviews the designing processes of clad metals to achieve specific requirements. The article discusses six categories of clad metal systems designed for corrosion control: noble metal clad systems, corrosion barrier systems, sacrificial metal systems, transition metal systems, complex multilayer systems, and clad diffusion alloys.

This article contains a table that lists the thermal conductivity of selected metals and alloys near room temperature. These include aluminum and aluminum alloys; copper and copper alloys; iron and iron alloys; lead and lead alloys; magnesium and magnesium alloys; nickel and nickel alloys; tin and tin alloys; titanium and titanium alloys; zinc and zinc alloys; and pure metals.

This article presents a table that lists the linear thermal expansion of selected metals and alloys. These include aluminum, copper, iron, lead, magnesium, nickel, tin, titanium, and zinc and their alloys. Thermal expansion is presented for specific temperature ranges.

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.

Selective plating, also known as brush plating, differs from traditional tank or bath plating in that the workpiece is not immersed in a plating solution (electrolyte). Instead, the electrolyte is brought to the part and applied by a handheld anode or stylus, which incorporates an absorbent wrapping for applying the solution to the workpiece (cathode). This article focuses on the selective plating systems that include a power pack, plating tools, anode covers, specially formulated plating solutions, and any auxiliary equipment required for the particular application. It provides a detailed account of the applications of selective plating, with examples. The article describes the advantages, limitations, key process elements, and health and safety considerations of selective plating. It also includes the most important industrial, government, and military specifications.

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.

Electroplated silver is used in both decorative and functional applications, such as engineering and electrical/electronic applications. This article explains the solution formulations and specifications of electrolytes used in silver plating.

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 a table that lists the density of metals and alloys. It presents information on aluminum, copper, iron, lead, magnesium, nickel, tin, titanium, and zinc, an their respective alloys. Information on wrought alloys, permanent magnet materials, precious metals, and rare earth metals is also listed.

Density allows for the conversion of uniform corrosion rates from units of weight (or mass) loss per unit area per time to thickness per unit time. This article contains a table that lists the density of metals, such as aluminum, copper, iron, stainless steel, magnesium, and lead, and their alloys.