This chapter presents an overview of families of brazing alloys that one is likely to encounter in a manufacturing environment. It discusses the metallurgical aspects of brazing and includes a survey of brazing alloy systems. A discussion of deleterious and beneficial impurities is provided with examples. The chapter also describes the application of phase diagrams to brazing.

This chapter provides an overview of a computational method, called CALPHAD, used for the study of phase equilibria in multicomponent systems. It describes the thermodynamic models and calculation techniques employed in the software and explains how it applies to complex alloys used in industry. It also provides examples showing how CALPHAD has been used to determine the formability of metallic glass, calculate the dilation of stainless steel during phase transformation, and predict the beta transus and approach curves of commercial titanium alloys.

This appendix discusses the general characteristics, composition, phase transformations, and properties of commercial stainless steels used for making high-quality knives.

This chapter describes the structures, phases, and phase transformations observed in metals and alloys as they solidify and cool to lower temperatures. It begins with a review of the solidification process, covering nucleation, grain growth, and the factors that influence grain morphology. It then discusses the concept of solid solutions, the difference between substitutional and interstitial solid solubility, the effect of alloying elements, and the development of intermetallic phases. The chapter also covers the construction and use of binary and ternary phase diagrams and describes the helpful information they contain.

This chapter discusses the construction, interpretation, and use of ternary phase diagrams. It begins by examining a hypothetical phase space diagram and several corresponding two-dimensional plots. It then describes one of the most basic tools of metallurgy, the Gibbs triangle, and explains how to construct tie lines to analyze intermediate compositions and phases. It also discusses the use of three-dimensional temperature-composition diagrams, three- and four-phase equilibrium phase diagrams, and binary and ternary phase diagrams associated with the iron-chromium-nickel alloy system.

Steels contain a wide range of elements, including alloys as well as residual processing impurities. This chapter describes the chemical composition of low-alloy AISI steels, which are classified based on the amounts of chromium, molybdenum, and nickel they contain. It explains why manganese is sometimes added to steel and how unintended consequences, such as the development of sulfide stringers, can offset the benefits. It also examines the effect of alloying elements on the iron-carbon phase diagram, particularly their effect on transformation temperatures.

This article discusses the role of alloying in the production and use of common refractory metals, including molybdenum, tungsten, niobium, tantalum, and rhenium. It provides an overview of each metal and its alloys, describing the compositions, properties, and processing characteristics as well as the effect of alloying elements. It also discusses strengthening mechanisms and, where appropriate, corrosion behavior.

This chapter describes the various phases that form in tool steels, starting from the base of the Fe-C system to the effects of the major alloying elements. The emphasis is on the phases themselves: their chemical compositions, crystal structures, and properties. The chapter also provides general considerations of phases and phase diagrams and the determination of equilibrium phase diagrams. It describes the formation of martensite, characteristics of alloy carbides, and the design of tool steels.

This chapter is a compilation of beryllium phase diagrams, representing more than 25 binary alloy systems from beryllium-aluminum to beryllium-zirconium. Each diagram is presented along with a summary and source reference.

Tools steels are defined by their wear resistance, hardness, and durability which, in large part, is achieve by the presence of carbide-forming alloys such as chromium, molybdenum, tungsten, and vanadium. This chapter describes the alloying principles employed in various tool steels, including high-speed, water-hardening, shock-resistant, and hot and cold work tool steels. It discusses the influence of alloy design on the evolution of microstructure and properties during solidification, heat treating, and hardening operations. It also describes critical phase transformations and the effects of partitioning, precipitation, segregation, and retained austenite.

This article discusses the effect of alloying on the composition, structure, properties, and processing characteristics of ordered intermetallic compounds, including nickel aluminides, iron aluminides, and titanium aluminides. It includes several data tables along with a list of typical applications.

Nonferrous metals are of commercial interest both as engineering materials and as alloying agents. This chapter addresses both roles, discussing the properties, processing characteristics, and applications of several categories of nonferrous metals, including light metals, corrosion-resistance alloys, superalloys, refractory metals, low-melting-point metals, reactive metals, precious metals, rare earth metals, and metalloids or semimetals. It also provides a brief summary on special-purpose materials, including uranium, vanadium, magnetic alloys, and thermocouple materials.

This article discusses the role of alloying in the production and use of low-expansion alloys such as iron-nickel (Invar), iron-nickel-chromium (Elinvar), and iron-nickel-cobalt (Super-Invar and Kovar). It explains how the coefficient of thermal expansion varies with nickel content and how it can be tailored, along with other properties, through appropriate alloying adjustments. The article also discusses the effect of alloying on Incoloy and Pyromet, which are classified as high-strength, controlled-expansion alloys.

This article discusses the properties, behaviors, and uses of cobalt and its alloys. It explains how cobalt alloys are categorized and describes the commercial designations and grades that are available. It also provides composition information and explains how alloying elements and carbides affect toughness, hardness, ductility, and strength as well as resistance to heat, corrosion, and wear.

Superalloys tend to operate in environments where they are subjected to high-temperature corrosion, oxidation, and the erosive effects of hot gases. This chapter discusses the nature of these attacks and the effectiveness of various protection methods. It describes the primary forms of oxidation, the development of protective oxides, and the conditions associated with mixed gas corrosion and hot corrosion attack. It discusses oxidation and corrosion testing, the equipment used, and various ways to present the associated data. It describes the effect of gaseous oxidation on different alloys, discusses the formation of oxide scale in the presence of mixed gases, and explains how alloy composition contributes to oxide growth. The chapter discusses the underlying chemistry of hot corrosion, how to identify its effects, and how it progresses under various conditions. It also discusses protective coatings, including aluminide diffusion, overlay, and thermal barrier types, and how they perform in different environments based on their ability to tolerate strain.

Stainless steels derive their name from their exceptional corrosion resistance, which is attributed to their finely tuned compositions. This chapter discusses the alloying elements used in stainless steels and the some of the processing challenges they present. One of the biggest challenges is that stainless steels cannot be hardened by heat treatment. As a result, they are highly sensitive to processing-induced defects and the formation of detrimental phases. The chapter explains how alloy design, phase equilibria, microstructure, and thermomechanical processing can be concurrently optimized to produce high-quality austenitic, ferritic, and duplex stainless steels.

Nickel and nickel alloys have an excellent combination of corrosion, oxidation, and heat resistance, combined with good mechanical properties. Nickel alloys can be divided into alloys that combine corrosion and heat resistance, superalloys for high-temperature applications, and special nickel alloys. Corrosion- and heat-resistant nickel alloys include commercially pure and low-alloy nickels, nickel-copper alloys, nickel-molybdenum and nickel-silicon alloys, nickel-chromium-iron alloys, nickel-chromium-molybdenum alloys, and nickel-chromium-iron-molybdenum-copper alloys. Special nickel alloys include electrical-resistance alloys, low-expansion alloys, magnetically soft alloys, and shape memory alloys. This chapter discusses the metallurgy, nominal composition, properties, applications, advantages, and disadvantages of these alloys. It also provides information on cobalt wear-resistant alloys and cobalt corrosion-resistant alloys.

Steels for hot-work applications, designated as group H steels in the AISI classification system, have the capacity to resist softening during long or repeated exposures to high temperatures needed to hot work or die cast other materials. These steels are subdivided into three classes according to the alloying approach: chromium hot-work steels, tungsten hot-work steels, and molybdenum hot-work steels. This chapter discusses the composition, characteristics, applications, advantages, and disadvantages of each of these steels.

Titanium alloys respond well to heat treatment be it to increase strength (age hardening), reduce residual stresses, or minimize tradeoffs in ductility, machinability, and dimensional and structural stability (annealing). This chapter describes the phase transformations associated with these processes, explaining how and why they occur and how they are typically controlled. It makes extensive use of phase diagrams and cooling curves to illustrate the effects of alloying and quenching on beta-to-alpha transformations and the conditions that produce metastable phases. It also examines several time-temperature-transformation diagrams, which account for the effect of cooling rate.

Nickel-base alloys used for low-temperature aqueous corrosion are commonly referred to as corrosion-resistant alloys (CRAs), and nickel alloys used for high-temperature applications are known as heat-resistant alloys, high-temperature alloys, or superalloys. The emphasis in this chapter is on the CRAs and in particular nickel-chromium-molybdenum alloys. The chapter provides a basic understanding of general welding considerations and describes the welding metallurgy of molybdenum-containing CRAs and of nickel-copper, nickel-chromium, and nickel-chromium-iron CRAs. It discusses the corrosion behavior of nickel-molybdenum alloys and nickel-chromium-molybdenum alloys. Information on the phase stability and corrosion behavior of nickel-base alloys is also included.