Search Results for transfer die forming

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 discusses the factors that influence temperature in forging operations and presents equations that can be used to predict and control it. The discussion covers heat generation and transfer, the effect of metal flow, temperature measurement, testing methods, and the influence of equipment-related parameters such as press speed, contact time, and tooling geometries.

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.

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 use of finite-element modeling in forging design. It describes key modeling parameters and inputs, mesh generation and computation time, and process modeling outputs such as metal flow, strain rate, loading profiles, and microstructure. It also includes a variety of application examples.

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 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 design and application of sheet forming presses. The discussion covers critical variables and design parameters, key components, basic machine configurations, and energy and load requirements. The chapter also discusses time-dependent characteristics, dimensional accuracy, and stiffness as well as die change procedures.

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 a relatively simple method for estimating forging loads and flow stresses. The method uses the slab analysis technique and accounts for material properties, friction and heat transfer, press ram speed, forging geometry, and billet and die temperatures. The chapter demonstrates the use of the method and compares the results with measured values.

This chapter addresses the issue of die failures in hot and cold forging operations. It describes failure classifications, fatigue fracture and wear mechanisms, analytical wear models, and the various factors that limit die life. It also includes several case studies in which finite-element modeling is used to predict die failure and extend die life.

This appendix is a glossary of terms and definitions associated with sheet metal forming.

This chapter covers the different types of wear encountered in metalworking processes. It discusses the mechanisms involved in adhesive, abrasive, chemical, and fatigue wear and key contributing factors, including the composition and structure of tool and workpiece materials, the characteristics of contact surfaces, and loading forces imposed by the process. It describes the nature of metal transfer between tool and workpiece surfaces and the role of lubricants, coatings, and textures. It also discusses the use of wear maps, the effects of adhesion, and material-lubricant interactions.

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.

Forging is a deformation process achieved through the application of compressive stresses. During the stroke, pressures and velocities are continuously changing and the initial lubricant supply must suffice for the duration of the operation. Lubricant residues and pickup products also change with time, further complicating the analysis of friction and wear. This chapter provides a qualitative and quantitative overview of the mechanics and tribology of forging in all of its forms. It discusses the effects of friction, pressures, forces, and temperature on the deformation and flow of metals in open-die, closed-die, and impression-die forging and in back extrusion and piercing operations. It presents various ways to achieve fluid-film lubrication in upset forging processes and examines the cause of barreling, defect formation, and folding in the upsetting of cylinders, rings, and slabs. It also explains how to evaluate lubricants, friction, and wear under hot, cold, and warm forging conditions and how to extend die life and reduce defects when processing different materials.

Prior to forging, it is often necessary to preform billet stock to achieve adequate material distribution. This chapter discusses the equipment used for such operations, including transverse rolling machines, electric upsetters, ring-rolling mills, horizontal presses, and rotary (orbital) and radial forging machines. It describes their basic operating principles as well as advantages and disadvantages.

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.