This chapter provides an overview of the blanking process and the forces and stresses involved. It discusses the factors that affect part quality and tool life, including punch and die geometry, stagger, clearance, and wear as well as punch velocities, misalignment, and snap-thru forces. It also discusses ultra-high-speed blanking, fine blanking, and shearing, and the use finite-element simulations to predict part edge quality.

This chapter discusses some of the more advanced methods and procedures used in failure analysis, including in-service material sampling, in situ microstructure analysis, and a form of punch testing that can determine the fracture toughness of any material from a tiny specimen. The chapter also covers quantitative fractography, fracture surface topography analysis, and the use of oxide dating as well as fault tree and failure modes and effects analysis (FMEA) and computational techniques.

This chapter provides a detailed analysis of the deep drawing process. It begins by explaining that different areas of the workpiece are subjected to different types of forces and loads, equating to five deformation zones. After describing the various zones, it discusses the effect of key process parameters including the draw ratio, material properties, geometry, interface conditions, equipment operating speed, and tooling. It then walks through the steps involved in predicting stress, strain, and punch force using the slab method and finite element analysis and presents the results of simulations conducted to assess the influence of blank diameter, thickness, and holding force as well as strain-hardening and strength coefficients. It also discusses the cause of defects in deep drawn rectangular cups and presents the case study of a deep drawn rectangular cup made from an aluminum blank.

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.

This chapter describes a sheet metal forming method, called hydroforming, that uses pressurized liquid and a shaped punch or die. It discusses the advantages and disadvantages of the two approaches, the effect of process variations, and tooling modifications intended to reduce sheet bulging. It identifies the factors that influence part quality and explains how finite-element analysis can be used to optimize hydroforming operations. It also discusses the economics of sheet hydroforming and presents several application examples.

This chapter presents two case studies; one demonstrating the use of finite-element analysis (FEA) in the design of a progressive die forming operation, the other explaining how software simulations helped engineers reduce thinning and eliminate cracking and deformation observed in clutch hubs formed using a three-step transfer die process. It also discusses the role of FEA and commercial software in the design of progressive dies.

This chapter describes joining by forming processes including riveting, clinching, crimping, and dieless joining techniques. It also discusses the fatigue behavior of clinched joints and the results of fatigue tests that compare clinched and spot welded joints.

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 discusses the process of cold forging and its effect on various materials. It describes billet preparation and lubrication procedures, cold upsetting techniques, and the use of slab analysis for estimating cold forging loads. It likewise describes extrusion processes, explaining how to estimate friction and flow stress and predict extrusion loads and energy requirements. The chapter also discusses the tooling used in cold forging, the parameters affecting tool life, and the relative advantages of warm forging.

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 discusses the factors that must be considered when selecting a lubricant for sheet metal forming operations. It begins with a review of lubrication regimes and friction models. It then describes the selection and use of sheet metal forming lubricants, explaining how they are applied and removed and how their pressure and temperature ranges can be extended by performance enhancing additives. The chapter also explains how sheet metal forming lubricants are evaluated in the laboratory as well as on the production floor and how tribological tests are conducted to simulate stamping, deep drawing, ironing, and blanking operations.

This chapter describes sheet metal forming operations, including cutting, blanking, piercing, and bending as well as deep drawing, spinning, press-brake and stretch forming, fluid forming, and drop hammer and electromagnetic forming. It also discusses the selection and use of die materials and lubricants along with superplastic forming techniques.

This chapter discusses the design and operation of electromechanical servo-drive presses. It begins by comparing the operating flexibility of servo-press drives with that of their conventional counterparts. It then explains the difference between direct-drive and belt and screw-driven servo presses and describes some of the innovations and improvements made possible with high-torque servo motors. The chapter provides examples of how servo presses are used in blanking, warm forming, and other applications and compares the operating characteristics of two 1100-ton presses, one driven by servo motors, the other by a mechanical crank.

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 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.

The several specific grades or compositions of tool steels have evolved over time and have been organized into useful groupings. This chapter presents the AISI classification system for tool steels, which categorizes tool steels by their alloying, applications, or heat treatment, and briefly describes the characteristics of each major group. It discusses selection criteria for tool steels, along with examples.

The conversion of feedstock into a shape involves the application of heat and pressure, and possibly solvents. This chapter discusses the operating principle, advantages, limitations, and applications of such shaping processes, namely additive manufacturing, cold isostatic pressing, die compaction, extrusion, injection molding, slip casting, slurry processes, and tape casting. Information on equipment setup, requirements, and the various factors influencing these processes are described. In addition, the chapter provides information on novel approaches and processing costs applicable to these shaping processes.

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 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.