Sheet forming failures divert resources from normal business activities and have significant bottom-line impact. This article focuses on the formation, causes, and limitations of four primary categories of sheet forming failures, namely necks, fractures/splits/cracks, wrinkles/loose metal, and springback/dimensional. It discusses the processes involved in analytical tools that aid in characterizing the state of a formed part. In addition, information on draw panel analysis and troubleshooting of sheet forming failures is also provided.

This datasheet provides information on key alloy metallurgy, mill product specifications, processing effects on physical and mechanical properties, and applications of high-strength aerospace alloys 2024 and Alclad 2024. It contains tables that list values of tensile property limits for 2024 sheet, plate, and round product forms. Figures illustrate the effect of stretching and aging on toughness of the 2024 sheet and the effect of temperature on tensile properties of 1.0 mm thick Alclad 2024-T3 sheet.

Aluminum and its alloys are among the more formable materials of commonly fabricated metals. This article discusses the formability, bendability, and springback of aluminum and its alloys. It describes the forming limit diagrams that illustrate the biaxial combinations of strain that can occur without splitting. The article reviews various bending methods, such as draw, compression, ram and press, roll, and stretch or tension bending. It describes the process variations of incremental sheet forming (ISF), such as single-point incremental forming, two-point incremental forming, and kinematic incremental sheet forming. The article concludes with a discussion on spinning, warm forming, and superplastic forming.

This article discusses the tribology of three main sheet forming processes: deep drawing, bending, and shearing. For each process, the basic principle of the forming process is briefly explained. Tribological phenomena observed in each process, such as wear and galling, are presented. Common methods of using lubricants and coatings in sheet forming processes are also described.

This article is a comprehensive collection of tables containing formulas for metals processing, namely, casting and solidification, flat (sheet) rolling, conical-die extrusion, wire drawing, bending, and deep drawing. Formulas for compression, tension, and torsion testing of isotropic materials are included. The article also lists the formulas for effective stress, strain, and strain rate (isotropic material) in arbitrary and principal coordinates; dimensionless groups in fluid mechanics; and anisotropic sheet materials at various loading conditions.

Simulation programs are becoming more effective tools in reducing the need for physical testing and the avoidance of costly downstream problems by solving the problems upfront in the early development stage. This article provides a brief review of the history and applied analysis of simple forming operations. It focuses on metal stamping simulation based on the finite-element methods or model (FEM) with emphasis on software tools using the three-dimensional FEM technology. The article discusses two aspects of particular importance in finite-element analysis of sheet forming and springback analysis: the type of solution algorithm/governing equation and the type of element. The article provides information on various models for material yield criteria.

Sheet forming comprises deformation processes in which a metal blank is shaped by tools or dies, primarily under the action of tensile stresses. This article discusses the classification of sheet-forming processes for obtaining desired dimensional features. It describes different process-related developments, namely, superplastic forming of aluminum, forming of tailor-welded blanks, rubber-pad forming, and high-velocity metal forming. The article explains cost-effective approaches of evaluating tooling designs prior to the manufacture of expensive steel dies and dieless forming techniques such as thermal forming and peen forming. It provides information on the application of advanced high-strength steels, magnesium alloys, and various ultrafine-grain materials for superplastic sheet forming. The article concludes with information on the development and application of simulation, design, and control of sheet-forming processes.

Bending is a common metalworking operation to create localized deformation in sheets (or blanks), plates, sections, tubes, and wires. This article emphasizes on the bending of sheet metal along with some coverage on flanging. It informs that variations in the bending stresses cause springback after bending, and discusses the variables and their effects on springback, as well as the methods to overcome or counteract them. These methods include overbending, bottoming or setting, and stretch bending. The article provides information on elastic bending, non-cylindrical bending, elastic-plastic bending, and pure plastic bending. Sheet metal bendability is a critical factor in many forming operations. The article illustrates the derivation of two relevant bend-ductility equations.

This article reviews the general characteristics of copper and copper alloys and explains how these characteristics affect the behavior of strip in different types of forming operations. These forming operations include blanking, piercing, bending, drawing and stretch forming, spinning, rubber-pad forming, and contour roll forming. Specialized forming operations such as hydraulic forming, embossing and swaging, and high-velocity metal forming are also reviewed. The article discusses the forming of smaller and larger parts from copper and copper alloy strips, as well as their property requirements and applications.

Sheet-forming processes provide considerable geometric and material flexibility in meeting these requirements, and design of parts for sheet forming must take into account these benefits as well as the limitations of the processes. This article reviews the basic forming operations and their general geometric features. These operations include hole making, flanging, bead and rib forming, and stretching and drawing for shallow or deep recesses. The article illustrates the general approach to design for sheet forming and the considerations that must be made for material savings and manufacturing ease, in addition to part function. It concludes with information on reducing the amount of scrap in sheet-forming operations.

This article briefly reviews the forming of steel tailor-welded blanks (TWB) with a discussion on the effects of welding on forming. It presents the parameters that are monitored to control the stamping operation for tailor-welded blanks. The article discusses weld factors such as the orientation of weld relative to metal movement in dies, the formability of TWB materials, die and press considerations, and specific factors for the drawing, stretching, and bending of steel tailor-welded blanks.

Bars, structural shapes, and long parts are straightened by bending, twisting, or stretching. This article describes the straightening of bars, shapes, and long parts by material displacement, heating, and presses. It explains the process of parallel-roll straightening, automatic press roll straightening, moving-insert straightening, parallel-rail straightening, and epicyclic straightening. The article concludes with a discussion on straightening in bar production.

This article focuses on the technology breakthroughs that make forming simulation a routine work throughout the industry. It discusses many forms of the computer-aided engineering (CAE) methodology. The article describes several failure criteria to predict the failure of sheet metal. It explains the numerical procedure for sheet metal forming and reviews the important technical issues in CAE simulations. The article provides information on the applications and process of metal-forming simulation. It also reviews the capabilities of major systems that are popular among sheet metal forming users worldwide.

This article illustrates the mechanics of the deep drawing of a cylindrical cup. It discusses the fundamentals of drawing and drawability. Sheet metal is drawn in either hydraulic or mechanical presses. The article summarizes the defects in drawing and factors considered in press selection for drawing. It explains the types of dies used for drawing sheet metal and the effects of process variables and material variables on deep drawing. The process variables that affect the success or failure of a deep-drawing operation include the punch and die radii, punch-to-die clearance, press speed, lubrication, and type of restraint of metal flow used. The article describes the process of redrawing and ironing of metals. Drawing of workpieces with flanges and drawing of hemispheres are also illustrated. The article also provides information on the reducing of drawn shells, methods for expanding portions of drawn workpieces, trimming, and deep drawing using fluid-forming presses.

Fine-blanking is a hybrid metal forming process that combines the technologies of stamping and cold extrusion. This article describes the three principal design features of the fine blanking process: the vee-ring, clearance between punch and die, and counterforce imposed by the ejector. It discusses the advantages and disadvantages of edge blanking and materials. The article reviews the classification of fine-blanking dies such as the moving-punch system and the fixed-punch system, and provides information on the mechanical and hydraulic fine-blanking presses.

In terms of forming, magnesium alloys are much more workable at elevated temperatures due to their hexagonal crystal structures. This article describes the deformation mechanisms of magnesium and provides information on the hot and cold forming processes of magnesium alloys and the lubricants used in the processes. It discusses the various forming processes of magnesium alloys. These include press-brake forming, deep drawing, manual and power spinning, rubber-pad forming, stretch forming, drop hammer forming, and precision forging.

Stretch forming is the forming of sheet, bars, and rolled or extruded sections over a die or form block of the required shape while the workpiece is held in tension. This article discusses the applicability, advantages, and machines and accessories of stretch forming. It provides a detailed discussion on four methods of stretch forming, namely, stretch draw forming, stretch wrapping, compression forming, and radial draw forming.

Statistics are extremely important tools in the operation of press shops, providing numerical process analysis capabilities. The most common use of statistics in the press shop is statistical process control (SPC) that uses statistical techniques such as control charts to analyze a process or its output to enable appropriate actions to be taken to achieve and maintain a state of statistical control. This article discusses the role of statistics in sheet metal forming operations, both in terms of SPC techniques, such as control charting, statistical deformation control, and experimental design, including single-variable studies, multivariable studies, and Taguchi experiments.

This article describes the various types of press construction and the factors that influence the selection of mechanically or hydraulically powered machines for producing parts from sheet metal. Presses are broadly classified, according to the type of frame used in their construction, into two main groups: gap-frame presses and straight-side presses. The article describes the various components of mechanical presses and hydraulic presses. It discusses important factors, such as the size, force, energy, and speed requirements, that influence the selection of a press. The article describes the roles of automatic handling equipment that can be categorized as feeding equipment, unloading equipment, and transfer equipment. It concludes with information on the common types of high-production presses, such as dieing machines, multiple-slide machines, transfer presses, fine blanking presses, and flexible-die forming presses.

Metal production mills produce flat metal sheet and strip products into coil forms that are subjected to further fabrication for shape correction. This article provides a discussion on the principle of shape correction and describes the role of various fabrication processes in shape correction. These processes include flattening, leveling, slitting, and cut-to-length.