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Titanium, like other metals, can be shaped, formed, and strengthened through deformation processes. This chapter describes the structural changes that occur in titanium during deformation and how they can be controlled. It discusses the role of slip, dislocations, and twinning, the effect of grain size and crystal orientation, the concept of texture strengthening, and the principles of strain hardening and superplasticity. It also discusses the effect of annealing and the difference between recrystallization and neocrystallization processes.

This chapter provides an overview of the physical metallurgy of beryllium, discussing phases and phase transformations, physical and mechanical properties, heat treatment, and alloying. It explains how the atomic structure of beryllium, particularly its sp hybrid state, contributes to the anisotropy of elastic constants and slip properties, resulting in a specific stiffness, or modulus-to-density ratio, six times higher than that of any other structural material.

This chapter is a detailed account of the history of development of titanium and its modern applications in the aerospace market. It begins by discussing the attempts made to produce titanium metal. This is followed by a discussion on the invention of a process for making titanium by William Kroll. Various studies on the properties on titanium and research programs related to the production of titanium sponge and titanium metal products are then described. The chapter concludes with a discussion of titanium use in jet engines.

This chapter describes aluminum applications in aircraft and space vehicles and the special alloys, tempers, and product forms required to meet the unique challenges of flight. It focuses on wrought alloys and products that comprise the bulk of aluminum aircraft structure. The chapter also provides a list of the aerospace alloys and their chemical compositions in common use as well as their application on aircraft.

From a fundamental standpoint, there are only two modes, or ways, in which metals can fracture under single, or monotonic, loads: shear and cleavage. There are fracture modes other than shear and cleavage. These include intergranular and quasi-cleavage fracture modes for single-load applications, and fatigue for multiple-load applications. Each of these fracture modes are discussed in this chapter. The factors affecting the ductile brittle relationship are also covered.

Deformation within a crystal lattice is governed principally by the presence of dislocations, which are two-dimensional defects in the lattice structure. Slip from shear stress is the most common deformation mechanism within crystalline lattices of metallic materials, although deformation of crystal lattices can also occur by other processes such as twinning and, in special circumstances, by the migration of vacant lattice sites. This appendix describes the notation used to specify lattice planes and directions and discusses the mechanisms of slip and twinning as well as the effect of stacking faults.

This article discusses the effects of alloying on the properties and behaviors of maraging steels. It describes how maraging steels differ from conventional steels in that they are strengthened, not by carbon, but by the precipitation of intermetallic compounds. It explains how maraging steels typically have high levels of nickel, cobalt, and molybdenum with little carbon content and how that affects their dimensional stability, fracture toughness, weldability, and resistance to stress-corrosion cracking.

There are numerous approximate methods, both analytical and numerical, for analyzing forging processes. None are perfect because of the assumptions made to simplify the mathematical approach, but all have merit. This chapter discusses the slab, upperbound, and finite element methods, covering basic principles, implementation, and advantages and disadvantages in various applications.

Moore's Law has driven many degree circuit features below the resolving capability of optical microscopy. Yet the optical microscope remains a valuable tool in failure analysis. This article describes the physics governing resolution and useful techniques for extracting the small details. It begins with the basic microscope column and construction. The article discusses microscope adjustments, brightfield and darkfield illumination, and microscope concepts important to liquid crystal techniques. It also discusses solid immersion lenses, infrared and ultraviolet microscopy and concludes with laser microscopy techniques such as thermal induced voltage alteration and external induced voltage alteration.

Steels are over 95% Fe, so a good starting point for understanding steel is to study the nature of solid iron. This chapter provides information on the composition, phase transformation, and associated changes in the crystal structure of pure iron at varying temperatures.

This chapter describes the effect of processing variables on the mechanical properties of beryllium, including tensile and yield strength, fracture toughness, creep and fatigue strength, ductile-to-brittle transition, and notch sensitivity. It also discusses the effects of chemical composition, impurities, and grain size and the use of hydrostatic testing.

Specimen preparation is the first step that determines the quality of the microstructural information that can be obtained using optical microscopy. This chapter describes the sample preparation methods that are applicable to most types of composite materials containing short discontinuous or continuous fibers. The sample preparation methods cover documentation and labeling of samples, sectioning the composite, clamp-mounting composite samples, mounting composite samples in casting resins, and the addition of contrast dyes to casting resins. Information on the molds used for mounting composite materials is provided. The steps recommended to achieve a good mounted specimen without voids or specimen pull-out are also described. The chapter discusses the processes for clamping mounted composite samples in automated polishing heads and mounting composite materials for hand polishing. A summary of the mounting technique is also included.

This chapter discusses the development of aluminum, its industry growth, and its modern uses in manufacturing. It begins with the biography of Charles Martin Hall, who invented the process for reducing aluminum from its ore. The evolution of aluminum production from the Pittsburgh Reduction Company to a pilot plant on Smallman Street in Pittsburgh, to a production plant in New Kensington, and to Niagara Falls, New York, is then described. This is followed by a discussion on early aluminum applications and the usage of lower-cost raw materials. The chapter provides information on aluminum production process integrated by Aluminum Company of America (Alcoa) and the numerous technical problems and solutions related to Alcoa's research from World War I to World War II. The aerospace applications for aluminum alloys are also presented. The chapter concludes with a section on aluminum alloys developed by Alcoa.

The mechanical properties of a material describe the relations between the stresses acting on the material and its resulting deformations. Stresses capable of producing permanent deformations, which remain after the stresses are removed, are considered in this chapter. The effects of cryogenic temperatures on the mechanical properties of metals and alloys are reviewed in this chapter; the effects on polymers and glasses are discussed briefly. The fundamental mechanisms controlling temperature-dependent mechanical behavior, phenomena encountered in low-temperature testing, and the mechanical properties of some representative engineering metals and alloys are described. Modifications of test procedures for low temperatures and sources of data are also included.

This appendix provides fracture toughness and tensile property data for aluminum alloys in the 2000, 6000, 7000, and 8000 series as well as B201 and D357 aluminum castings and powder metal alloys.

This chapter describes the iron-carbon phase diagram, its modification by alloying elements, and the effect of carbon on the chemistry and crystallography of austenite, ferrite, and cementite found in Fe-C alloys and steels. It also lays the groundwork for understanding important metallurgical concepts, including solubility, critical temperature, dislocation defects, slip, and diffusion, and how they affect the microstructure, properties, and behaviors of steel.

Stainless steels have a wide variety of applications for household products, food-handling equipment, major appliances, medical equipment, and industrial equipment. Stainless is also featured in many architectural designs and monuments. Many of the most important applications of stainless steel can be found in the transportation industry, where both the cutlery martensitic and the chromium-nickel austenitic stainless steels have been used. This chapter provides a detailed discussion on these applications.

Stress-corrosion cracking (SCC) in magnesium alloys was first reported in the 1930s and, within ten years, became the focus of intense study. This chapter provides a summary of all known work published since then on the nature of SCC in magnesium alloys and how it is related to composition, microstructure, and heat treatment. It describes the types of environments where magnesium alloys are most susceptible to SCC and the effect of contributing factors such as temperature, strain rate, and applied and residual stresses. The chapter also discusses crack morphology and what it reveals, provides information on proposed cracking mechanisms, and presents a practical approach for preventing SCC.