This chapter discusses the various factors pertinent to gravity permanent mold (GPM) castings, along with their advantages, limitations, and significance. The discussion covers the geometric factors, process and manufacturing elements, gating practices, and feeding principles of and pouring systems in GPM. The influences of mold coatings on GPM and low pressure permanent mold castings are described. The chapter also discusses various processes involved in the engineering of core boxes and cooling of GPM for casting integrity and cycle time control. It provides information on some of the processes involved in post-casting operations, namely de-coring and de-gating. The key design aspects for consideration in water quenching during the T6 heat treatment are reviewed. The chapter also provides information on two critical cycle events important in engineering at the manufacturing facility: tipper cycle planning and table or cell cycle planning.

This chapter presents guidelines for product designers to choose the best process and alloys while designing a casting. The discussion covers some of the factors pertinent to the selection of the best process for the product function and performance, namely geometric factors, mechanical properties, tooling cost per piece, and overall cost factors. The chapter contains tables listing several markets, products, popular processes, and common alloys and the common processes used for a variety of markets and products.

The gravity permanent mold (GPM) process produces castings of high strength and integrity with good surface finish and consistent dimensions. This chapter lists castings produced using GPM and semipermanent mold (SPM). It illustrates the basic elements of a conventional tilt pour machine. The chapter also provides an overview of the high-volume rotary table, high-volume production rotary manufacturing cell, cycle time planning, sizes of tilt pour machine and table, and improvement of turntable uptime. It also presents some of the common semipermanent molded castings.

This chapter is a collection of tables listing: cast alloy designations of Aluminum Association, along with their general applications; the chemical compositions of the frequently used alloys for gravity permanent molds, low-pressure permanent molds, squeeze castings, and die castings; the typical tensile properties of die cast alloys; and the designations of different heat treatments and their description. The tables also list the temperatures and times of typical heat treatment cycles for different permanent mold cast alloys; typical components in sand, gravity, and low-pressure permanent mold castings and die castings, the functional requirements of each process, and the corresponding suitable alloys and heat treatments; and alloys that are high vacuum die cast for structural castings. The chapter also presents examples of photomicrographs of some alloys cast by different processes.

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 highlights the different melting, holding, and dosing furnaces that are available for the alternative casting processes used for the production of aluminum castings. Melting furnaces are grouped into four broad categories: crucible furnaces; reverberatory furnaces (or reverbs); stack melting furnaces (also called stack melters), tower melting furnaces, or jet melting furnaces; and electric coreless induction furnaces are detailed in this chapter. Factors influencing the choice of the melting, holding, and dozing equipment are presented. Equipment for recycling machined chips is also addressed.

This chapter begins with information on the historical development of aluminum alloy castings. It then covers the basic factors involved in the selection of a casting process. This is followed by sections describing the various categories of casting processes and their variants: expendable mold gravity-feed casting, nonexpendable (permanent) mold gravity feed casting, and pressure die casting. Next, the chapter describes the technologies used to produce premium engineered castings and when such castings may be relevant. The chapter concludes with descriptions of other process technologies used with castings, including metallurgical bonding, metal-matrix composites, and hot isostatic pressing.

Almost all metals and alloys are produced from liquids by solidification. For both castings and wrought products, the solidification process has a major influence on both the microstructure and mechanical properties of the final product. This chapter discusses the three zones that a metal cast into a mold can have: a chill zone, a zone containing columnar grains, and a center-equiaxed grain zone. Since the way in which alloys partition on freezing, it follows that all castings are segregated to different categories. The different types of segregation discussed include normal, gravity, micro, and inverse. The chapter also provides information on grain refinement and secondary dendrite arm spacing and porosity and shrinkage in castings. It concludes with a brief overview of six of the most important casting processes in industries: sand casting, plaster mold casting, evaporative pattern casting, investment casting, permanent mold casting, and die casting.

This chapter describes the processes and alloys used in the casting of aluminum components, the advantages and disadvantages of the different shape-casting methods, and the major factors that influence alloy selection for shape-casting applications. An overview of the heat treatment of cast products is also included.

This chapter discusses various factors pertinent to the applications of low-pressure permanent mold casting process, namely decorative automotive wheels, critical safety structural components, and chassis components.

This chapter is a brief account of various factors pertinent to the development of an engineering component. The discussion covers the disciplines and interactions of design development, engineering of component design, validation of design and process analysis, and matrix of design and manufacturing elements.

The low-pressure permanent molding (LPPM) and semipermanent molding (LPSPM) processes are versatile, and they meet the quality requirements of a variety of high-integrity, large-sized, and thin-walled aluminum castings for various industries. This chapter presents the major features, operation sequence, advantages, and applications of LPPM, LPSPM, and counter-pressure casting.

Aluminum casting alloy compositions parallel those of wrought alloys in many respects. However, because work hardening plays no significant role in the development of casting properties, the use and purposes of some alloying elements differ in casting alloys versus wrought alloys. This chapter provides information on specifications and widely used designation systems and alloy nomenclature for aluminum casting alloys. It describes the composition of seven basic families of aluminum casting alloys: aluminum-copper, aluminum-silicon-copper, aluminum-silicon, aluminum-silicon-magnesium, aluminum-magnesium, aluminum-zinc-magnesium, and aluminum-tin. The chapter discusses the effects of alloying elements on the properties of cast aluminum. It provides information on various alloys that are grouped with respect to their applications or major performance characteristics.

This chapter covers the practices and procedures used for shape casting metals and alloys. It begins with a review of the factors that influence solidification and contribute to the formation of casting defects. It then describes basic melting methods, including induction, cupola, crucible, and vacuum melting, and common casting techniques such as sand casting, plaster and shell casting, evaporative pattern casting, investment casting, permanent mold casting, cold and hot chamber die casting, squeeze casting, semisolid metal processing, and centrifugal casting.

Hot isostatic pressing (HIP) is a process refinement available to address internal porosity in castings. The HIP process may be used, in particular, for applications requiring very high quality and performance. This chapter discusses the principles, advantages, and disadvantages of HIP. It describes the effect of HIP on tensile properties and on the fatigue performance of aluminum alloy castings. In addition, the chapter discusses the processes involved in radiographic inspection of HIP-processed castings.

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.