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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.

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.

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 discusses the quenching process and its adaptation to induction heat treating. It describes the three stages of quenching, the cooling characteristics of various types of quenchants, and the details of nearly a dozen compatible quenching methods. It also explains how to verify whether a quenchant can cool a workpiece fast enough to achieve martensitic transformation without cracking or distortion.

Casting is one of the most economical manufacturing processes for providing shape to components of machinery and is used in a wide range of industries. This chapter is a brief account of the advantages, applications, limitations, and market growth of aluminum casting. It also provides information on the process of conversion of steel and iron parts to aluminum.

This chapter provides a brief review of the history of metal working processes, the use of lubricants, and the study of friction and wear. It also explains how the book is organized and describes the method of treatment used by the authors.

This chapter discusses the maintenance needs of major components in induction heat-treating systems, including power supplies, heat stations, capacitors, high-frequency output stages, induction coils, water systems, quench systems, and fixturing.

Iron and steel castings require cleaning as they come out of the shakeout units to remove any burned sand and sand that may remain stuck from the mold. This chapter presents the casting cleaning operation sequence. The sequence includes shot blasting; decoring or removal of cores from castings; degating or removal of runners, gates, and feeders; and flash removal and automation. The chapter also presents the objectives of heat treatment and discusses its processes. The chapter describes product quality control. Quality checks are grouped into three categories: material checks, product checks, and functional checks.

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.

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.

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.

Elevated-temperature failures are the most complex type of failure because all of the modes of failures can occur at elevated temperatures (with the obvious exception of low-temperature brittle fracture). Elevated-temperature problems are real concerns in industrial applications. The principal types of elevated-temperature failure mechanisms discussed in this chapter are creep, stress rupture, overheating failure, elevated-temperature fatigue, thermal fatigue, metallurgical instabilities, and environmentally induced failure. The causes, features, and effects of these failures are discussed. The cooling techniques for preventing elevated-temperature failures are also covered.

This appendix is a compilation of terms and definitions associated with the processing, microstructure, and properties of powder metal stainless steels.

This chapter describes the properties and attributes of various classes of metalworking lubricants, including mineral oils; natural oils, fats, derivatives, and soaps; synthetic fluids (olefins, esters, polyglycols, ionic liquids); compounded lubricants (oils, greases, fats); aqueous lubricants (emulsions, synthetics, solutions); and a wide range of coatings and carriers. It also discusses solid-film lubricants (oxide films, polymer films, layer-lattice compounds) and environmental and safety concerns.

Rolling is unique in that it cannot be conducted without friction. Friction draws the workpiece into the roll gap and facilitates its passage through the deformation zone. This chapter provides an overview of the mechanics and tribology of flat rolling processes and explains how various aspects of the theory apply to shape rolling as well. It derives numerous equations and models to help quantify the forces, torque, and power involved in rolling operations and the associated heating, slip, strain distribution, and deformation in both the workpiece and rolls. It describes the friction and wear that occur in hot and cold rolling under hydrodynamic and mixed-film lubrication; the influence of viscosity, film thickness, rolling speed, interface pressure, pass reduction, and lubricant breakdown; and the effect of surface finish and defects. The chapter also provides best practices for evaluating, applying, and treating lubricants for industrially important materials including iron-base, nickel-base, and aluminum alloys.

This chapter discusses the processes involved in the heat treatment of steel, namely austenitizing, hardening, quenching, and tempering. It begins with an overview of austenitizing of steels by induction heating, followed by a discussion on the processes involved in transformation of the soft austenite into martensite or lower bainite in the hardening operation. The chapter provides information on various quenching systems and a description of quenching techniques, namely austempering, martempering, and patenting. Difficulties associated with hardening of steel are discussed. Further, the chapter describes the equipment used for and principal variables of tempering. It discusses the causes for various forms of embrittlement due to tempering. Information on multiple tempering, protective-atmosphere tempering, and selective tempering are also provided, along with processes involved in selection of tempering temperature. The chapter ends with a section discussing various effects, advantages, and disadvantages of precipitation hardening.

This chapter discusses the metallurgy, phase structure, thermal processing, and applications of martensitic stainless steels. The phenomenon of martensite formation is explained. A table listing the compositions of martensitic stainless steels is also presented.

This chapter is a detailed account of the general characteristics and effects of and the methods for preventing or reducing different categories of wear failures, namely abrasive (erosive, grinding, and gouging), adhesive, and fretting wear.