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 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 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 various types of cushion systems used in forming presses and their effect on part quality. It begins with a review of the deep drawing process, explaining that wrinkling, tearing, and fracture are the result of excess or insufficient material flow, which can be prevented by maintaining the correct amount of holding force on the periphery of the blank. It then describes how blank holding force is generated in double-action presses and the extent to which displacement profiles can be adjusted on both the inner and outer slides. The discussion then turns to single-action presses that incorporate some type of cushion system. The chapters describes the many ways that cushion systems are implemented in forming presses and the force and displacement characteristics achievable with each method. It also explains how multipoint cushion systems are designed and how they facilitate uniform metal flow into the die cavity of large deep-drawn parts.

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 describes the general characteristics of two commonly classified metalworking processes, namely hot working and cold working. Primary metalworking processes, such as the bulk deformation processes used to conduct the initial breakdown of cast ingots, are always conducted hot. Secondary processes, which are used to produce the final product shape, are conducted either hot or cold. The chapter discusses the primary objectives, principal types, advantages, and disadvantages of both primary and secondary metalworking processes. They are rolling, forging, extrusion, sheet metal forming processes, blanking and piercing, bending, stretch forming, drawing, rubber pad forming, and superplastic forming.

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 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 discusses the design and operation of hydraulic presses. It begins by describing the role of each major component in a hydraulic system. It then explains the difference between pump-driven and accumulator-driven presses and the types of applications for which are suited. The chapter goes on to describe the load, energy, and time-dependent characteristics of hydraulic presses and the factors that determine accuracy. It also explains how hydraulic presses are used for deep drawing, fine blanking, and hydroforming as well as warm forming and hot stamping operations.

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 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 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 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 describes the equipment and processes used to form titanium alloy parts. It discusses the advantages and disadvantages of hot and cold forming, the factors that influence formability, and the effect of forming temperature and lubricants. It describes common processes, including brake forming, stretch forming, deep drawing, and spin forming as well as roll forming, drop-hammer forming, tube bulging and bending, and superplastic forming. It also discusses dimpling and joggling and the use of hot sizing to correct springback.

Hot stamping is a forming process for ultrahigh-strength steels (UHSS) that maximizes formability while minimizing springback. This chapter covers several aspects of hot stamping, including the methods used, the effect of process variables, and the role of finite-element analysis in process development and die design. It also discusses heating methods, cooling mechanisms, and the role of coatings in preventing oxidation.

Sheet metal spinning is a forming technique that produces axially symmetric hollow bodies with nearly any contour. It is often used in combination with flow forming and shear spinning to manufacture a wide range of complex parts. This chapter describes the operating principles, stress states, and failure modes of each process along with typical applications and tooling requirements.

The increased use of advanced high-strength steels to achieve weight reduction in automobiles has led to the development of innovative tool designs and manufacturing processes. Among these technologies and processes are: real-time process control, active drawbeads, active binders, flexible binders, and flexible rolling. This chapter presents the implementation, advantages, disadvantages, and applications of these processes and technologies.

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.

The various types of stainless steel have very different deformation characteristics in terms of strain hardening and anisotropy. It is important to understand and exploit these characteristics to optimize forming of stainless steels. This chapter discusses the various deformation processes involved in sheet-forming techniques, namely stretch forming and deep drawing. In addition, it provides information on some of the factors pertinent to cold-heading and hot forming of stainless long products.