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Steel castings are produced in thousands of designs for different applications. They fill needs in many industries, including transportation, construction machinery, earthmoving equipment, rolling mills, mining, oil and gas exploration, and power generation. This chapter touches upon the variety of applications for which steel castings can be supplied and the ranges of casting size and complexity. Photographs in this chapter provide an understanding of these applications, their size and complexity, and the types of cast steels produced.

Unlike conventional quench and temper heat treatment, austempering is an iron and steel heat-treatment process that enhances mechanical properties through the isothermal transformation of austenite with a minimum amount of quenching stresses. This chapter begins with a discussion of austemperability requirements. Then outlines of austenitizing and austempering cycles and resultant microstructures are presented. This is followed by sections discussing the mechanical properties, advantages, limitations, machinability, process variants, and applications of austempered ductile iron (ADI). Information on the growth of premachined ADI components is also provided. Further, the chapter describes two slightly different systems for austempering: atmospheric-salt and salt-salt systems. Finally, it presents general guidelines for component designers, casting manufacturers, and heat treaters to apply ADI more widely and with improved success.

Planning and laying out casting facilities involve a number of vital factors, such as available infrastructure, selection of suitable sites, orientation of operations and process flow, markets and products, operating parameters, and targeted hourly output and annual capacity. This chapter presents guiding principles and layout concepts with these factors in mind. It also presents steps for the creation of a plant layout. Plant layout involves the arrangement of processing areas, machinery, and equipment for the efficient conversion of raw materials into finished products. The chapter discusses general guidelines for developing a layout.

This chapter provides an overview of aluminum die casting and the equipment used. It discusses the advantages and limitations of the die casting process and the design and operation of hot- and cold-chamber die casting machines. It also discusses clamping systems and forces and the factors affecting die life, including die materials, metal injection cycles, and lubrication. A typical die casting cell layout is also provided.

Iron and steel have been the most useful materials to meet the needs of several industries for many decades. Each iron and steel alloy offers unique attributes that make them the best choice for an application. This chapter provides an overview of each ferrous alloy—gray iron, malleable iron, compacted graphite iron (CGI), ductile iron, austempered ductile iron (ADI), and carbon steel and low-alloy steel; its versatile attributes; and its individual applications. A large section of the chapter covers the impact of electric vehicles on the future of the iron and steel castings industry, including discussion on electric vehicle categories and weights; impact of center of gravity on stability and steering; lightweighting incentives; and engineering for improved suspension.

This chapter provides an account of the pre-Columbian history of metal discovery in America and then reviews the development of metallurgy in the Middle Ages from early wrought iron practices to the use of coke in iron casting. It discusses the influence of the family of Abraham Darby in England in the development of ironmaking.

This chapter discusses the crystal structures of steel and cast iron, the iron-iron carbide equilibrium diagram, microconstituents or phases in the iron-iron carbide phase diagram, the iron-carbon carbide-silicon equilibrium diagram of cast irons, and the influence on microstructure by base elements and alloying elements. Graphitization, cooling rates, and heat treatment effects are covered. There also is discussion on inoculation benefits, flake graphite types and typical applications, evolution of cast iron types, ASTM specification A247 for graphite shapes, and selection of the best molding process. A large table lists typical material choices for various applications.

This chapter discusses the effect of powder metallurgy on the design and production of nuclear energy reactors, wind turbines, biomedical devices, and gas turbine engines.

This chapter covers common types of erosion, including droplet, slurry, cavitation, liquid impingement, gas flow, and solid particle erosion, and major types of wear, including abrasive, adhesive, lubricated, rolling, and impact wear. It also covers special cases such as galling, fretting, scuffing, and spalling and introduces the concepts of tribocorrosion and biotribology.

Cast irons, like steels, are iron-carbon alloys but with higher carbon levels than steels to take advantage of eutectic solidification in the binary iron-carbon system. Like steel, heat treatment of cast iron includes stress relieving, annealing, normalizing, through hardening, and surface hardening. This chapter introduces solid-state heat treatment of iron castings, covering general considerations for heat treatment and discussing the processes, advantages, and disadvantages of heat treatment of cast iron.

This chapter presents basic principles and the theoretical results of heat transport in solids. Thermal conductivity and thermal diffusivity are the principal properties discussed. Discussions are also included on the effects of temperature, magnetic field, and metallurgical variations caused by composition, processing, and heat-treatment differences. Numerous graphs illustrate the qualitative and quantitative effects of these variables. Measurement methods and associated accuracies and pertinent empirical correlations are presented.

The mechanical properties of a material describe the relations between the stresses acting on the material and its resulting deformations. Stresses capable of producing permanent deformations, which remain after the stresses are removed, are considered in this chapter. The effects of cryogenic temperatures on the mechanical properties of metals and alloys are reviewed in this chapter; the effects on polymers and glasses are discussed briefly. The fundamental mechanisms controlling temperature-dependent mechanical behavior, phenomena encountered in low-temperature testing, and the mechanical properties of some representative engineering metals and alloys are described. Modifications of test procedures for low temperatures and sources of data are also included.

Steel is broadly classified as plain-carbon steels, low-alloy steels, and high-alloy steels. This chapter begins by describing microconstituents of low- and medium-carbon steel, including bainite and martensite. This is followed by a section discussing the effect of alloying elements on steel. Then, it provides an overview of steel casting applications. Next, the chapter reviews engineering guidelines for steel castings and feeder design. The following section provides information on feeding aids. Further, the chapter describes the elements of gating systems for steel castings. It also describes the alloys, properties, applications, and engineering details of steel. Finally, the chapter explains defects in steel castings and presents guidelines for problem solving with examples.

This chapter discusses the advantages, limitations, and applications of various aluminum casting processes, namely green sand casting process, air set or no-bake molding process, vacuum molding process, evaporative foam casting process, and die casting process. The processes covered also include gravity permanent molding, low-pressure permanent molding, counter pressure, squeeze casting, investment casting, rapid prototype casting, cast forge hybrid, and semisolid metal processes.

This chapter reviews the types of friction that are of concern in tribological systems along with their associated causes and effects. It discusses some of the early discoveries that led to the development of friction laws and the understanding that friction is a system effect that can be analyzed based on energy dissipation. It describes the stick-slip behavior observed in wiper blades, the concept of asperities, and the significance of the shape, lay, roughness, and waviness of surfaces in sliding contact. It explains how friction forces are measured and how they are influenced by speed, load, and operating environment. It also covers rolling contact and fluid friction and the effect of lubrication.

Stainless steels have a wide variety of applications for household products, food-handling equipment, major appliances, medical equipment, and industrial equipment. Stainless is also featured in many architectural designs and monuments. Many of the most important applications of stainless steel can be found in the transportation industry, where both the cutlery martensitic and the chromium-nickel austenitic stainless steels have been used. This chapter provides a detailed discussion on these applications.

This article discusses the effect of alloying on high-strength low-alloy (HSLA) steels. It explains where HSLA steels fit in the continuum of commercial steels and describes the six general categories into which they are divided. It provides composition data for standard types or grades of HSLA steel along with information on available mill forms, key characteristics, and intended uses. The article explains how small amounts of alloying elements, particularly vanadium, niobium, and titanium, control not only the properties of HSLA steels, but also their manufacturability.

Many companies conduct only metallurgical evaluations in the wake of failures, discovering nothing more than the physical mechanism by which the failure occurred. The origin of failures, however, is often complex, involving not only physical mechanisms, but also human behavior and latent factors. Failures may also involve multiple parts, entire machines, or processes of any size and shape. The chapter examines the unique aspects of many failures and explains how they can sometimes be traced to systemic issues. It also covers the reasons why products fail, including improper service or operation, improper maintenance, improper testing, assembly errors, fabrication or manufacturing errors, and design errors. The case of the Tacoma Narrows Bridge collapse is presented to illustrate the consequence of overlooked factors, in this case, wind dynamics, and the importance of identifying root causes to prevent repeat failures.