This chapter details the types of heat treating furnaces. It discusses energy sources and modes of heat transmission. The chapter’s focus is on the different types of batch furnaces and continuous furnaces, including box furnaces, integral-quench batch furnaces, pit furnaces, furnaces for heat treating with fluidized beds, and straight chamber continuous furnaces.

Carbonitriding introduces and diffuses atomic nitrogen into the surface steel during carburization. This chapter focuses on case composition of a carbonitrided case, case depth, case hardenability, hardness gradients, void formation, and applications of carbonitriding. The chapter discusses furnaces suitable for carbonitriding, atmosphere constituents, batch furnace atmospheres, continuous furnace atmospheres, safety, temperature selection, quenching, tempering, and hardness testing of a carbonitrided case.

The melting furnace is a critically important piece of equipment in a foundry; it influences the balance between the metal required by molding machines and the melting capacity. This chapter presents the features, types, advantages, and applications of furnaces suitable for iron and steels such as cupolas, induction furnaces, and arc furnaces.

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.

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 describes the basic steps in the steelmaking process. It explains how iron is reduced from ore in the liquid state through the classic blast furnace process and in the solid state by direct reduction. It discusses the conversion of iron to steel and the technological advancements that led from open hearth steelmaking to basic oxygen processes and ultimately the electric arc furnace (EAF). It describes the versatility, efficiency, and scalability of the EAF process and its impact on recycling and sustainability. It explains how EAF refining and deoxidation practices have changed over time, and describes secondary refining processes such as degassing, homogenization, rinsing, and remelting.

This chapter describes the processes involved in alloy production, including melting, casting, solidification, and fabrication. It discusses the effects of alloying on solidification, the formation of solidification structures, supercooling, nucleation, and grain growth. It describes the design and operation of melting furnaces as well as melting practices and the role of fluxing. It also discusses casting methods, nonferrous casting alloys, and atomization processes used to make metal powders.

This chapter discusses various processes involved in the production of steel from raw materials to finished mill products. The processes include hot rolling, cold rolling, forging, extruding, or drawing. The chapter provides a detailed description of two main furnaces used for making steel: the electric arc furnace and the basic oxygen furnace. It also provides information on the classification and specifications for various steels, namely, plain carbon steels, low-carbon steels, medium-carbon plain carbon steels, and high-carbon plain carbon steels. The chapter concludes with a general overview of the factors influencing corrosion in iron and steel and a brief discussion of corrosion-resistant coatings.

This chapter, a detailed account of furnaces and related equipment for heat treating, begins by describing three basic modes of heat transmission, namely conduction, convection, and radiation, followed by a discussion on the working principle, applications, advantages, and disadvantages of furnaces classified based on the heat transfer medium employed. The types of furnaces covered are batch-type, continuous-type, liquid bath, fluidized bed, and vacuum. The subsequent sections provide information on furnace parts, fixtures, quenching mediums, and quenching systems. The final section of the chapter describes the types of atmospheres available, emphasizing their applications and limitations.

A fluidized-bed furnace system can be used for the gas nitriding process. This chapter focuses on fluidized-bed nitriding. It discusses the methods of heating a fluidized bed. The heating system can be electrical or gas, and internal or external. The chapter describes nitriding and oxynitriding processes in the fluidized-bed furnace. It also explains how to operate the fluid bed for nitriding. The chapter provides a discussion on the measurement of the gas dissociation.

Furnaces for heat treatment of tool steels include ceramic-lined salt bath furnaces, vacuum furnaces, controlled-atmosphere furnaces, and fluidized-bed furnaces. This chapter describes the classification, operating principles, application, advantages, and disadvantages of each type of furnace.

This chapter provides an overview of the types of melting furnaces and refractories for steel casting. It then presents information about arc furnace melting and induction melting cycles. The chapter also describes methods for the removal of phosphorous, the removal of sulfur, and the recovery of elements from slag. It then presents an overview of argon-oxygen-decarburization (AOD) refining and types of ladles. The chapter describes chemical analysis that is performed using either optical emission or x-ray spectrographs.