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This chapter covers special fault-tree analysis topics, including the use of transfer symbols, INHIBIT gates, sequential AND gates, state-of-the-part versus state-of-the-system considerations, and the fault tree to identify redundancy-defeating failures.

In order to understand how the strength of steels is controlled, it is extremely useful to have an elementary understanding of two topics: solutions and phase diagrams. This chapter provides an introduction to these topics with suitable examples.

This appendix provides references for additional information on titanium and its alloys. The references are organized by topic based on the author’s recommendations. Topics include physical metallurgy, corrosion, processing, applications and developments, and general background.

This appendix contains sample problems with worked solutions pertaining to the use of binary phase diagrams. The problems require the determination of favorable temperatures and compositions, the amount and composition of phases in an alloy at a given temperature, the amount of a certain phase in different steels, and the microstructure developed in different alloys.

The mechanical behavior of a material is its response to an applied load or force. Important mechanical properties are strength, hardness, stiffness, and ductility. This chapter discusses three principal ways in which these properties are tested: tension, compression, and shear. Important tensile properties that can be determined by the tensile test include yield strength, ultimate tensile strength, ductility, resilience, and toughness. The chapter describes the effects of stress concentrations on ductile metals under cyclic loads. Other topics covered include combined stresses, yield criteria, and residual stresses of metals.

This chapter provides a brief introduction to superalloys and their high-temperature capabilities. It explains how and why they were developed and highlights some of their unique properties, behaviors, and characteristics. It discusses their basic metallurgy, how they are processed, and where they are typically used. It also includes nominal composition data for more than 120 superalloys and a concise overview of the major topics in the book.

This chapter discusses the similarities and differences of forging and forming processes used in the production of wrought superalloy parts. Although forming is rarely concerned with microstructure, forging processes are often designed with microstructure in mind. Besides shaping, the objectives of forging may include grain refinement, control of second-phase morphology, controlled grain flow, and the achievement of specific microstructures and properties. The chapter explains how these objectives can be met by managing work energy via temperature and deformation control. It also discusses the forgeability of alloys, addresses problems and practical issues, and describes the forging of gas turbine disks. On the topic of forming, the chapter discusses the processes involved, the role of alloying elements, and the effect of alloy condition on formability. It addresses practical concerns such as forming speed, rolling direction, rerolling, and heat treating precipitation-hardened alloys. It presents several application examples involving carbide-hardened cobalt-base and other superalloys, and it concludes with a discussion on superplasticity and its adaptation to commercial forging and forming operations.

This appendix includes selected references on topics related to the production and application of superalloys, including properties and microstructure; melting/ingot breakdown; forging/powder metallurgy; machining, heat treating, joining, refurbishment/repair; investment casting; coatings/corrosion; and modeling.

This chapter provides an overview of the microstructure-property relationships associated with aluminum-silicon alloys. It includes information on commercial designations and grades, phase compositions, solidification paths, alloying elements, and intermetallic phases. It also provides solubility data and maps out the topics covered in subsequent chapters in the book.

This chapter outlines the topics covered in the book and explains why and to whom the book was written. The book is intended for engineers, metallurgists, and failure analysts who work with materials and components that operate in high-temperature corrosive environments. It covers eight basic modes of high-temperature corrosion as well as the effect of external and residual stresses. It also provides an extensive amount of engineering data associated primarily with commercial alloys.

Austenitization is the heat treatment of steel in the austenite region, and it is conducted for two reasons. One is to obtain austenite as a necessary precursor for heat treatment, and this is the main emphasis of this chapter. The other is to chemically homogenize steel, so that concentration gradients formed during solidification upon casting are minimized; this is briefly described in this chapter. Austenitization topics covered in this chapter are dendritic segregation in steels, austenitization to remove coring, ingot segregation, grain growth behavior, formation of austenite, austenite grain size, heating in the austenite region, and practical austenitizing temperatures.

This article is intended to help engineers understand why the fatigue behavior of weldments can be such a confusing and seemingly contradictory topic and hopefully to clarify this complex subject. It first reexamines the factors influencing the fatigue behavior of an individual weldment using extensive experimental data and a computer model that simulates the fatigue resistance of weldments. Next, the process of fatigue in weldments is discussed in general terms, and the service conditions that favor long crack growth and the conditions that favor crack nucleation are contrasted. The article then presents experimental data that show the effect of weldment geometry on fatigue resistance. Several useful geometry classification systems are compared. Finally, a computer model is employed to investigate the behavior of two hypothetical weldments: a discontinuity-containing ("Nominal") weldment and a discontinuity-free ("Ideal") weldment.