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.

The primary objectives of the rolling process are to reduce the cross section of the incoming material while improving its properties and to obtain the desired section at the exit from the rolls. This article illustrates a rolling sequence for the fabrication of bars, shapes, and flat products from blooms, billets, and slabs. It describes two methods for shapes or sections: universal rolling and caliber rolling. The article provides information on two-high mills and three-high mills. Specialty mills for thin sheets, namely, the Sendzimir mill and planetary mill, are discussed. The article analyzes the components of a computer controlled system for high-speed mills. Steels and nonferrous materials are also discussed. The article concludes with information on the defects in flat, bar, or shaped products due to heating and rolling practices.

This article focuses on the various techniques for removing contaminants in the surface preparation of steel for hot-dip coatings: wet cleaning methods, including alkaline cleaning, electrolytic cleaning, chemical pickling, and electrolytic pickling; flame cleaning and furnace-atmosphere techniques, such as Sendzimir oxidation/reduction method; other specialized methods, namely, fluxes, mechanical cleaning, and ultrasonic methods; or a combination of these.

This article discusses the general characteristics, primary and secondary fabrication methods, product forms, and corrosion resistance of zirconium and hafnium. It describes the physical metallurgy of zirconium and its alloys, providing details on allotropic transformation and anisotropy that profoundly influences the engineering properties of zirconium and its alloys. Tables listing the values for chemical composition and tensile properties for nuclear and nonnuclear grades of zirconium are also provided.

Rolling is the process of reducing the thickness or changing the cross section of a workpiece by compressive forces applied through a set of rolls. This article emphasizes flat rolling and illustrates basic flat-rolling process used to reduce the thickness of a rectangular cross section. It provides a discussion on hot rolling, cold rolling, and warm rolling, as well as lubrication in rolling. The article reviews the lubrication for iron-base and nickel-base materials, light metals, copper-base alloys, and titanium alloys. It discusses the wear mechanism in rolling: abrasion, adhesion, and fatigue, as well as oxidative and corrosive wear. Surface modification techniques, such as hardening by induction heat treating, weld overlay, thermal spray coating, coating via physical vapor deposition (PVD), and laser surface treatment, are also discussed for improving roll service life.

Zirconium, hafnium, and titanium are produced from ore that generally is found in a heavy beach sand containing zircon, rutile, and ilmenite. This article discusses the processing methods of these metals, namely, liquid-liquid separation process, distillation separation process, refining, and melting. It also discusses the primary and secondary fabrication of zirconium and hafnium and its alloys. The article talks about the metallurgy of zirconium and its alloys with emphasis on allotropic transformation, cold work and recrystallization, anisotropy and preferred orientation, and the role of oxygen. It concludes by providing useful information on the applications of reactor and industrial grades of zirconium alloys.

Cemented carbides belong to a class of hard, wear-resistant, refractory materials in which the hard carbide particles are bound together, or cemented, by a ductile metal binder. Cermet refers to a composite of a ceramic material with a metallic binder. This article discusses the manufacture, composition, classifications, and physical and mechanical properties of cemented carbides. It describes the application of hard coatings to cemented carbides by physical or chemical vapor deposition (PVD or CVD). Tungsten carbide-cobalt alloys, submicron tungsten carbide-cobalt alloys, and alloys containing tungsten carbide, titanium carbide, and cobalt are used for machining applications. The article also provides an overview of cermets used in machining applications.

Cemented carbides belong to a class of hard, wear-resistant, refractory materials in which the hard carbide particles are bound together, or cemented, by a soft and ductile metal binder. The performance of cemented carbide as a cutting tool lies between that of tool steel and cermets. Almost 50% of the total production of cemented carbides is used for nonmetal cutting applications. Their properties also make them appropriate materials for structural components, including plungers, boring bars, powder compacting dies and punches, high-pressure dies and punches, and pulverizing hammers. This article discusses the manufacture, microstructure, composition, classifications, and physical and mechanical properties of cemented carbides, as well as their machining and nonmachining applications. It examines the relationship between the workpiece material, cutting tool and operational parameters, and provides suggestions to simplify the choice of cutting tool for a given machining application. It also examines new tool geometries, tailored substrates, and the application of thin, hard coatings to cemented carbides by chemical vapor deposition and physical vapor deposition. It discusses the tool wear mechanisms and the methods available for holding the carbide tool. The article is limited to tungsten carbide cobalt-base materials.

Wrought copper and copper alloys are produced in various mill-product forms for a variety of applications due to their high electrical conductivity, corrosion resistance, ease of fabrication, and good heat-transfer properties. This article describes the manufacturing processes used to produce wrought copper and copper alloys in the form of sheet and strip products, tubular products, and wire and cable. Common processes include melting, casting, hot and cold rolling, milling or scalping, annealing, cleaning, slitting, cutting, and leveling. In addition, the article discusses stress-relaxation characteristics of copper alloys.

Cemented carbides, best known for their superior wear resistance, have a range of industrial uses more diverse than that of any other powder metallurgy product including metalworking and mining tools and wear-resistant components. This article discusses raw materials and manufacturing methods used in the production of cemented carbides, the physical and mechanical properties of carbides, and wear mechanisms encountered in service. Emphasis is placed on tungsten carbide-cobalt (WC-Co) or tungsten carbide-nickel (WC-Ni) materials as used in nonmachining applications. Nominal composition and properties of representative cemented carbide grades and their applications are listed in a table.

Ceramic-metal composites, or cermets, combine the heat and wear resistance of ceramics with the formability of metals, filling an application niche that includes cutting tools, brake pads, heat shields, and turbine components. This article examines a wide range of cermets, including oxide cermets, carbide and carbonitride cermets, boride cermets, and other refractory types. It describes the powder metallurgy process by which cermets are produced, examining each step from powder preparation to post treatment. It discusses forming and compacting, injection molding, extrusion, rolling, pressing, slip casting, and sintering. It also discusses fundamental concepts such as chemical bonding, chemical composition, microstructure, and the development of physical and mechanical properties.