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.

This article describes the methods used for coloring anodized aluminum coatings: integral coloring, electrolytic coloring, chemical coloring, and organic dyeing. It discusses organic dye chemistry in terms of single-component organic dyes and multicomponent dyes. The article reviews optimal dyeing conditions, such as temperature, time, concentration, and pH. It concludes with a discussion on the factors considered for choosing a coloring method: the desired shade, light fastness, heat fastness, and contamination.

A sacrificial coating applied to a steel substrate can add 20 years or more of life to the substrate, depending on its thickness and composition. Different techniques to apply sacrificial coatings offer various characteristics that contribute to corrosion resistance. This article discusses thermal spray, hotdipping, and electroplating processes used to apply coatings in steel structures. It describes the corrosion attributes of the resulting coatings and discusses the methods of protecting steel from corrosion using aluminum and zinc coatings.

This article provides an overview of some common sheet steel coatings available. It discusses the formability differences between coated and bare steel and provides some general guidelines on the forming of coated steels. Coated steels are classified according to the nature of the substrate, the type of coating, and the method used for its application. The article describes various coating types for steels such as zinc-coated steels, aluminum-coated steels, tin-coated steels, terne-coated steels, and organic-coated steels.

From the standpoint of corrosion protection of iron and steel, metallic coatings can be classified into two types: noble coatings and sacrificial coatings. This article focuses on hotdipped zinc, aluminum, zinc-aluminum alloy and aluminum-zinc alloy coatings. It discusses the Sendzimir process and the Cook-Norteman process, which are the two commercial processes that are used for almost all hot-dip galvanized sheet steel in the United States. The article provides a discussion on the aqueous corrosion and atmospheric corrosion of galvanized steel and aluminized steel, as well as the intergranular corrosion of galvanized steel.

Vapor-deposition processes fall into two major categories, namely, physical vapor deposition (PVD) and chemical vapor deposition (CVD). This article describes major deposition processes such as sputtering, evaporation, ion plating, and CVD. The list of materials that can be vapor deposited is extensive and covers almost any coating requirement. The article provides a table of some corrosion-resistant vapor deposited materials. It concludes with an overview of the applications of CVD and PVD coatings and a discussion on coatings for graphite, the aluminum coating of steel, and alloy coatings for aircraft turbines, marine turbines, and industrial turbines.

This article discusses the processes involved in continuous hotdip coating of steel sheets, namely, hot and cold line processing, surface preparation, and post treatment. It outlines the properties and microstructures of metals and their alloys used in this process. The coatings considered in this article include metal coatings, such as zinc coatings, and alloy coatings, such as zinc-iron, types 1 and 2 aluminum, Zn-5AI, Zn-55AI, and lead-tin coatings.

Thermal spray coatings (TSCs) are surface coatings engineered to provide wear-, erosion-, abrasion-, and corrosion-resistant coatings for original equipment manufacture and for the repair and upgrading of in-service equipment. This article presents an overview of five thermal spray processes and the specific flame and arc spray processes used to preserve large steel components and structures. It describes the TSC selection guide and an industrial process procedure guide for applying aluminum and zinc TSCs onto steel.

Steel sheet is often coated in coil form prior to fabrication to save time, reduce production costs, and streamline operations. This article examines the most common precoating methods and provides a metallurgical understanding of how they impact the manufacturability, performance, and service life of the host material. The article covers metallic coatings, including zinc, aluminum, zinc-aluminum alloys, tin, and terne; pretreatment or phosphate coatings; and preprimed and painted finishes based on organic coatings.