This article focuses on the electroless gold plating technique, describing the advantages and limitations, applications, and properties of plated deposits. It also reviews process variables of the technique, including gold concentration, reducing agent, agitation, and contaminants.

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.

Gold electroplating was invented in 1840. During the first 100 years electrodeposited gold was used primarily for its aesthetic appeal as a decorative finish. This article provides a description of the gold plating process and the electrolytes used. It discusses the decorative and industrial applications of gold plating. The article reviews factors affecting the dragout of gold solution.

Metallic nonelectrolytic alloy coatings produced from aqueous solutions are commercially used in several industries, including electronics, aerospace, medical, oil and gas production, chemical processing, and automotive. Nonelectrolytic coating systems use two types of reactions to deposit metal onto a part: electroless and displacement. This article explains the various types of electroless and dispersion alloy coating systems. It provides information on the processing of parts, process control, deposit analysis, and equipment used for coating nonelectrolytic displacement alloys. The article concludes with a discussion on the safety and environmental concerns associated with nonelectrolytic deposition processes.

Aluminum components are often plated with other metals to mitigate the effects of corrosion and wear, improve application performance, and extend service life. This article discusses some of the more common aluminum plating processes, including electroplating, immersion plating, and electroless plating, and describes various plating materials and the types of applications in which they are used. It provides critical processing details such as temperatures, ratios, ranges, times, and rates. The article explains how to prepare aluminum components for electroplating, discussing surface roughening, anodizing, and immersion procedures along with expected results.

The process of coating plastics with metals for functional purposes is called metallizing of plastics. This article discusses the metallizing of plastics, provides information on its history, and gives a short note on applications and adhesion properties of metallic coatings. It also discusses the selection of plastics for plating. This article also describes metallizing techniques, including plating (electrolytic or electroplating), vacuum metallizing and thermal spraying, and environmental considerations. The article discusses the quality assurance procedures for metallized plastic parts which include tests that assess the quality of the finish, coating thickness, adhesion, and corrosion resistance, and gives a short note on service performance, which includes service condition classifications.

Electroless, or autocatalytic, metal plating is a nonelectrolytic method of deposition from solution that can be plated uniformly over all surfaces, regardless of size and shape. The plating's ability to plate onto nonconductors is an advantage that contributes to the choice of electroless copper in various applications. This article provides information on the bath chemistry and deposit properties of electroless copper and discusses the applications of electroless copper plating, such as printed wiring boards, decorative plating-on-plastic, electromagnetic interference shielding, and hybrid and other advanced applications. It describes two commercial processes, pretreatment and post-treatment. The article reviews the solutions used, controls and control equipment, and performance criteria of electroless copper plating. It concludes with information on the environmental and safety issues associated with electroless copper plating.

This article discusses the various factors that affect the corrosion performance of electroplated coatings. It describes the effects of environment and the deposition process on substrate coatings. The article provides a discussion on the electrochemical techniques capable of predicting the corrosion performance of a plated part. It reviews the designs of coating systems for optimal protection of the substrate. The article also discusses controlled weathering tests and accelerated tests used to predict and determine the relative durability of the coating.

Electroless nickel plating is used to deposit nickel without the use of an electric current. This article provides an overview of the solution composition and characteristics of the electroless nickel bath. It focuses on the metallurgical, mechanical and physical properties of electroless nickel-phosphorus coatings and electroless nickel-boron coatings. The effect of electroless nickel coatings on the fatigue strength of steel is also described. The article includes information on the recommended pretreatment procedures for different ferrous alloys, aluminum alloys, and copper alloys. It presents a detailed account of the equipment and various processes—including bulk and barrel plating—involved in electroless nickel plating, and discusses hydrogen relief methods. The article includes a comprehensive table on nickel plating applications, and concludes with information on electroless nickel coatings on composites and plastics.

The selection of surface treatments for copper and copper alloys is generally based on application requirements for appearance and corrosion resistance. This article describes cleaning, finishing, and coating processes for copper and copper alloys. These processes include pickling and bright dipping, abrasive blast cleaning, chemical and electrochemical cleaning, mass finishing, polishing and buffing, electroless plating, immersion plating, electroplating, passivation, coloring, and organic coatings.

Plastic deformation of one or both metals is required to obtain bonding in cold welding. This article presents a theoretical model, to explain the bond strength, based on metallographic studies and continuum mechanical analysis of the local plastic deformation in the weld interface. It describes the bonding mechanisms, with illustrations. The article discusses the alternative methods of surface preparation and quality control of the weld interface of a cold weld. It concludes with a description of a variety of metal-forming processes suitable for production of cold welds, namely, rolling, indentation, butt welding, extrusion, and shear welding.

Soldering represents the primary method of attaching electronic components, such as resistors, capacitors, or packaged integrated circuits, to either printed wiring board whose defects is minimized by consideration of proper PWB design, device packages, and board assembly. This article discusses the categories that are most important to successful electronic soldering, namely, solders and fluxes selection, nature of base materials and finishes, solder joint design, and solderability testing.

Ultrasonic welding (USW) is effectively used to join both similar and dissimilar metals with lap-joint welds. This article describes procedure considerations for the ultrasonic welding of specific material types. It reviews difficult-to-weld alloys, such as carbon and low-alloy steels, high-strength steels, and stainless steel, and provides information on the applications of weldable alloys such as aluminum alloys and copper alloys. The article concludes with a discussion on welding of dissimilar metal (nonferrous-to-nonferrous) combinations and its applications.

Copper can be electrodeposited from numerous electrolytes. Cyanide and pyrophosphate alkalines, along with sulfate and fluoborate acid baths, are the primary electrolytes used in copper plating. This article provides information on the chemical composition, plating baths, and operating conditions of electrodeposition processes for chromium plating, nickel plating, iron plating, cadmium plating, zinc plating, indium plating, lead plating, tin plating, silver plating, gold plating, brass plating, bronze plating, tin-lead plating, zinc-iron plating, and zinc-nickel plating. The article also discusses selective plating, electroforming, and other processes and where they are typically used.

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.