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This chapter provides readers with worked solutions to more than 25 problems related to compositional impurities and structural defects. The problems deal with important issues and challenges such as the design of low-density steels, the causes and effects of distortion in different crystal structures, the ability to predict the movement of dislocations, the influence of impurities on defects, the relationship between gain size and material properties, the identification of specific types of defects, the selection of compatible metals for vacuum environments, and the effect of twinning planes on stacking sequences. The chapter also includes problems on how the formation of precipitates can produce slip planes and how grain boundaries can act as obstacles to dislocation motion.

This chapter briefly discusses the characteristics of mechanical twins and stacking faults in close-packed planes. It provides an overview of the composition, microstructures, thermodynamics, processing, deformation mechanism, mechanical properties, formability, and special attributes of twinning-induced plasticity steels.

This chapter presents an overview on the twins and stacking faults. It then provides an overview of the compositions, microstructures, thermodynamics, processing, deformation mechanism, mechanical properties, formability, and special attributes of twinning-induced plasticity steels.

This chapter discusses steel’s compositions, metallurgical phases, microstructures, and heat treatments. It then presents the structure-property relationships of steel. The chapter describes the deformation and strengthening mechanisms of steel. It also presents an overview of deformation processing and annealing.

In a perfect crystalline structure, there is an orderly repetition of the lattice in every direction in space. Real crystals contain a considerable number of imperfections, or defects, that affect their physical, chemical, mechanical, and electronic properties. Defects play an important role in processes such as deformation, annealing, precipitation, diffusion, and sintering. All defects and imperfections can be conveniently classified under four main divisions: point defects, line defects, planar defects, and volume defects. This chapter provides a detailed discussion on the causes, nature, and impact of these defects in metals. It also describes the mechanisms that cause plastic deformation in metals.

This chapter discusses the compositions, metallurgical phases, microstructure, heat treatment, grades, and structure-property relationships of steels. In addition, it describes the mechanisms involved in deformation, strengthening, and annealing of steels.

This appendix provides a detailed overview of the crystal structure of metals. It describes primary bonding mechanisms, space lattices and crystal systems, unit cell parameters, slip systems, and crystallographic planes and directions as well as plastic deformation mechanisms, crystalline imperfections, and the formation of surface or planar defects. It also discusses the use of X-ray diffraction for determining crystal structure.

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.

Creep occurs in any metal or alloy at a temperature where atoms become sufficiently mobile to allow the time-dependent rearrangement of structure. This chapter begins with a section on creep curves, covering the three distinct stages: primary, secondary, and tertiary. It then provides information on the stress-rupture test used to measure the time it takes for a metal to fail at a given stress at elevated temperature. The major classes of creep mechanism, namely Nabarro-Herring creep and Coble creep, are then covered. The chapter also provides information on three primary modes of elevated fracture, namely, rupture, transgranular fracture, and intergranular fracture. The next section focuses on some of the metallurgical instabilities caused by overaging, intermetallic phase precipitation, and carbide reactions. Subsequent sections address creep life prediction and creep-fatigue interaction and the approaches to design against creep.

Alloying, heat treating, and work hardening are widely used to control material properties, and though they take different approaches, they all focus on imperfections of one type or other. This chapter provides readers with essential background on these material imperfections and their relevance in design and manufacturing. It begins with a review of compositional impurities, the physical arrangement of atoms in solid solution, and the factors that determine maximum solubility. It then describes different types of structural imperfections, including point, line, and planar defects, and how they respond to applied stresses and strains. The chapter makes extensive use of graphics to illustrate crystal lattice structures and related concepts such as vacancies and interstitial sites, ion migration, volume expansion, antisite defects, edge and screw dislocations, slip planes, twinning planes, and dislocation passage through precipitates. It also points out important structure-property correlations.

Dual-phase (DP) steels have the widest usage in automotive industry because of their excellent combination of strength and ductility. This chapter provides an overview of the composition, microstructure, processing, deformation mechanism, mechanical properties, formability, and special attributes of DP steels.

Dual-phase (DP) steels have the widest usage in the automotive industry because of their excellent combination of strength and ductility. This chapter presents the composition, microstructure, mechanical properties, formability, and attributes of DP steels. It also discusses the basic approaches for the commercial production of DP steels.

This chapter examines the phenomena of deformation and fracture in metals, providing readers with an understanding of why it occurs and how it can be prevented. It begins with a detailed review of tension and compression stress-strain curves, explaining how they are produced and what they reveal about the load-carrying characteristics of engineering materials. It then discusses the use of failure criteria and the determination of yielding and fracture limits. It goes on to describe the mechanisms and appearances of brittle and ductile fractures and stress rupture, providing detailed images, diagrams, and explanations. It discusses the various factors that influence strength and ductility, including grain size, loading rate, and temperature. It also provides information on the origin of residual stresses, the concept of toughness, and the damage mechanisms associated with creep and stress rupture, stress corrosion, and hydrogen embrittlement.

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 chapter summarizes the performance attributes of advanced high-strength steels, namely stiffness, strength, strain hardening, fatigue, crashworthiness, formability, toughness, and bake hardening.

The performance attributes of advanced high-strength steels are summarized in this chapter. These attributes include stiffness, strength, strain hardening, fatigue, crashworthiness, formability, toughness, and bake hardening.