This chapter discusses the factors that influence the load-deformation relationship at the heart of most metal forming operations. It describes the changes that occur in tensile test samples and the various ways test data can be plotted and analyzed, particularly for design purposes. It discusses the effect of normal and planar anisotropy, the development and use of flow stress curves, and how formability is usually measured and expressed. It explains how formability measurements serve as a guide for process and tool design engineers as well as others. It also discusses the development and use of forming limit curves and the extensive amount of information they provide.

This chapter describes incremental sheet forming processes, including single-point, two-point, and kinematic (two tool) techniques. It provides information on the tooling and equipment used, work flow and forming parameters, process mechanics and forming limits. It also discusses multistage forming strategies, process modeling and simulation, and advanced hybrid forming processes.

This chapter is a brief account of the composition, microstructures, heat treatment, deformation mechanisms, mechanical properties, formability, and special attributes of austenitic stainless steels.

This chapter discusses the forming characteristics of dual-phase (DP) and transformation-induced plasticity (TRIP) steels. It begins with a review of the mechanical behavior of advanced high-strength steels (AHSS) and how they respond to stress-strain conditions associated with deformation processes such as stretching, bending, flanging, deep drawing, and blanking. It then describes the complex tribology of AHSS forming operations, the role of lubrication, the effect of tool steels and coatings, and the force and energy requirements of various forming presses. It also discusses the cause of springback and explains how to predict and compensating for its effects.

This chapter begins with a review of the mechanics of bending and the primary elements of a bending system. It examines stress-strain distributions defined by elementary bending theory and explains how to predict stress, strain, bending moment, and springback under various bending conditions. It describes the basic principles of air bending, stretch bending, and U- and V-die bending as well as rotary, roll, and wipe die bending, also known as straight flanging. It also discusses the steps involved in contour (stretch or shrink) flanging, hole flanging, and hemming and describes the design and operation of press brakes and other bending machines.

This chapter describes the processes involved in the fabrication of wrought and cast metal products. It discusses deformation processes including bending and forming, material removal processes such as milling, cutting, and grinding, and joining methods including welding, soldering, and brazing. It also discusses powder consolidation, rolling, drawing and extrusion, and common forging methods.

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 chapter provides a concise, design-oriented summary of more than 30 sheet forming processes within the categories of bending and flanging, stretch forming, deep drawing, blank preparation, and incremental and hybrid forming. Each summary includes a description and diagram of the process and a bullet-point list identifying relevant equipment, materials, variations, and applications. The chapter also discusses critical process variables, interactions, and components and the classification of sheet metal parts based on geometry.

This chapter discusses the use of modeling and simulation technology in the development of sheet metal forming processes. It describes the five major steps involved in finite-element analysis and the various ways functions of interest can be approximated at each point or node in a finite-element mesh. It explains how to obtain input data, what to expect in terms of output data, and how to predict specific types of defects. In addition, it presents several case studies demonstrating the use of finite elements in blanking and piercing, deep drawing of round and rectangular cups, progressive die sequencing, blank holder force optimization, sheet hydroforming, hot stamping, and springback and bending of advanced high-strength steels. It also discusses the factors that affect the accuracy of finite element simulations such as springback, thickness variations, and nonisothermal effects.

This chapter lays the groundwork for understanding electrode kinetics associated with corrosion. It presents a simple but useful theory relating kinetics to the polarization behavior of half-cell reactions. The theory is based on the observation that electrode potentials vary as a function of current density or charge transfer in a given area. The chapter explains how to measure and plot electrode potentials and currents and how to interpret the resulting polarization curves. It also discusses the effects of concentration gradients, explaining how they cause diffusion and, in some cases, produce changes in electrode potential.

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

This chapter introduces the concepts of mechanical properties and the various underlying metallurgical mechanisms that can be used to alter the strength of materials. The mechanical properties discussed include elasticity, plasticity, creep deformation, fatigue, toughness, and hardness. The strengthening mechanisms covered are solid-solution strengthening, cold working, and dispersion strengthening. The effect of grain size on the yield strength of a material is also discussed.

Sheet metal forming operations consist of a large family of processes, ranging from simple bending to stamping and deep drawing of complex shapes. Because sheet forming operations are so diverse in type, extent, and rate, no single test provides an accurate indication of the formability of a material in all situations. However, as discussed in this chapter, the uniaxial tensile test is one of the most widely used tests for determining sheet metal formability. This chapter describes the effect of material properties and temperature on sheet metal formability. Information on the types of formability tests is also provided. The chapter discusses the processes involved in uniaxial and plane-strain tensile testing. Examples include the uniaxial tensile test and the plane-strain tensile test which are subsequently described.

This chapter provides an overview of the composition, microstructures, processing, deformation mechanism, mechanical properties, formability, and special attributes of complex-phase steels.

This chapter discusses the complex polarization characteristics of active-passive metals and addresses related problems in interpreting their corrosion behavior. It begins by presenting several experimentally derived polarization curves for iron, comparing and contrasting them with the iron-water Pourbaix diagram. It then explains how anodic polarization is extremely sensitive to the environment and, as a result, a reasonably complete curve for a given metal-environment system usually can only be inferred. It goes on to describe how such curves are constructed, demonstrating the procedures for a wide range of alloys and environments. The examples also show how factors such as alloy concentration, crystal lattice orientation, temperature, and dissolved oxygen affect corrosion behavior.

This chapter focuses on mechanical behavior under conditions of uniaxial tension during tensile testing. It begins with a discussion of properties determined from the stress-strain curve of a metal, namely, tensile strength, yield strength, measures of ductility, modulus of elasticity, and resilience. This is followed by a section describing the parameters determined from the true stress-true strain curve. The chapter then presents the mathematical expressions for the flow curve. The chapter reviews the effect of strain rate and temperature on the stress-strain curve and describes the instability in tensile deformation and stress distribution at the neck in the tensile specimen. It discusses the processes involved in ductility measurement and notch tensile test in tensile specimens. The parameter that is commonly used to characterize the anisotropy of sheet metal is covered. Finally, the chapter covers the characterization of fractures in tensile test specimens.

This chapter describes the effect of temperature and strain rate on the mechanical properties and forming characteristics of aluminum and magnesium sheet materials. It discusses the key differences between isothermal and nonisothermal warm forming processes, the factors that affect heat transfer, die heating techniques, and press systems. It also discusses the effect of forming temperature, punch velocity, blank size, and other parameters on deep drawing processes, making use of both experimental and simulated data.