Search Results for non-cylindrical bending

This chapter provides basic concepts and background for customer-related manufacturing processes applied to aluminum products including forming, joining and welding, surface treatments, and machinability. It reviews the selection criteria, key testing regimes, and original equipment manufacturer (OEM) requirements. The chapter also presents examples that demonstrate the importance of choosing the correct alloy and temper to successfully meet the OEM fabrication criteria.

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 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 presents the criteria, methods, and benefits of cast-weld construction.

This chapter begins with a review of some of the terms used in the gear industry to describe the design of gears and gear geometries. It then discusses the types of gears that operate on parallel shafts, intersecting shafts, and nonparallel and nonintersecting shafts. Next, the processes involved in the selection of gear are discussed, followed by information on the basic stresses applied to a gear tooth, the strength of a gear tooth, and the most widely used gear materials. Further, the chapter briefly reviews gear manufacturing methods and the heat treating processing steps including prehardening processes, through hardening, and case hardening processes.

This chapter discusses the ways in which the evolution of filament winding software systems has capitalized on the inherent flexibility of computer numerical controlled winding machines and enhanced their productivity. It provides a detailed discussion on different types of geometries that can be wound, from the simple to the highly complex, with insight into the limitations, advantages, and challenges of each. Components covered include classic axisymmetric parts (rings, pipes, driveshafts, pipe reducers, tapered shafts, closed-end pressure vessels, and storage tanks), nonround sections (aeromasts, airfoils, box sections, and fuselage sections), curved-axis parts (elbows, ducts), and special applications (tees). Basic winding concepts, such as band pattern, are discussed and explained, and some simple predictive formulae are introduced. The chapter also provides examples of programming various geometries using advanced software tools and discusses how various materials, such as rovings, tow-preg, prepreg tape, and woven materials, affect winding program generation.

This chapter reviews various ways to classify failure categories and summarizes the basic types, causes, and mechanisms of damage, with particular consideration given to whether the likelihood of the types of damage can or cannot be influenced by the heat treating of steel parts. The classical organization for types of damage (failures) is as follows: deformation, fracture, wear, corrosion or other environmental damage, and multiple or complex damage. The chapter also provides some examples of lack of conformance to specification that may at first look like the heat treater did something wrong, but where other contributing factors made it difficult or impossible for the heat treater to meet the specification.

This article presents six case studies of failures with steel forgings. The case studies covered are crankshaft underfill; tube bending; spade bit; trim tear; upset forging; and avoidance of flow through, lap, and crack. The case studies illustrate difficulties encountered in either cold forging or hot forging in terms of preforge factors and/or discontinuities generated by the forging process. Supporting topics that are discussed in the case studies include validity checks for buster and blocker design, lubrication and wear, mechanical surface phenomenon, forging process design, and forging tolerances. Wear, plastic deformation processes, and laws of friction are introduced as a group of subjects that have been considered in the case studies.

This chapter addresses the challenge of selecting an appropriate stress-corrosion cracking (SCC) test to evaluate the serviceability of a material for a given application. It begins by establishing a generic model in which SCC is depicted in two stages, initiation and propagation, that further subdivide into several zones plus a transition region. It then discusses SCC test standards before describing basic test objectives and selection criteria. The chapter explains how to achieve the required loading conditions for different tests and how to prepare test specimens to determine elastic strain, plastic strain, and residual stress responses. It also describes the difference between smooth and precracked specimens and how they are used, provides information on slow-strain-rate testing and how to assess the results, and discusses various test environments and procedures, including tests for weldments. The chapter concludes with a section on how to interpret time to failure, threshold stress, percent survival, stress intensity, and propagation rate data, and assess the precision of the associated tests.

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 article discusses the steps in the primary processing of stainless steels: melting, refining, remelting, casting, and hot rolling. It provides information of the major categories of defects in hot rolled stainless steels, namely hot mill defects, inclusion-related defects, and hot ductility-related defects.

This chapter summarizes the various kinds of gear wear and failure and how gear life in service is estimated and discusses the kinds of flaws in material that may lead to premature gear fatigue failure. The topics covered are alignment, gear tooth, surface durability and breakage of gear tooth, life determined by contact stress and bending stress, analysis of gear tooth failure by breakage after pitting, and metallurgical flaws that reduce the life of gears. The chapter briefly reviews some components in the design and structure of each gear and/or gear train that must be considered in conjunction with the teeth to enhance fatigue life.

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 appendix is a compilation of terms and definitions related to composite filament winding.

Mechanical treatments such as grinding and shot peening are often employed in the production of case-carburized parts. Grinding, besides restoring precision, removes carbide films, internal oxidation, and high-temperature transformation products. Shot peening strengthens component surfaces and induces a stress state that increases fatigue resistance. This chapter describes both processes as well as roller burnishing. It explains how these treatments are applied and how they influence the microstructure, properties, and behaviors of case-hardened components. It also addresses process challenges, particularly in regard to grinding.

This chapter provides a practical overview of the tools and techniques used to assess the tribological aspects of metal forming processes. It describes test methods that have been developed to evaluate bulk deformation and sheet metal forming processes along with lubricant rheology, friction forces, and stress and strain distributions. It explains how to measure temperature between tooling and workpiece surfaces as well as surface topography and composition, film thickness, and wear. It also discusses the benefits of reduced-scale and simulation testing and the transfer of results from one process to another.

This chapter explains that the key to forging is understanding and controlling metal flow and influential factors such as tool geometry, the mechanics of interface friction, material characteristics, and thermal conditions in the deformation zone. It also reviews common forging processes, including closed-die forging, extrusion, electrical upsetting, radial forging, hobbing, isothermal forging, open-die forging, orbital forging, and coining.

This chapter explains various aspects of the foundry process that the design engineer should consider when designing steel castings. It discusses special feeding aids, such as tapers, padding, ribs, and chills that may be used by foundry personnel to promote directional solidification. The chapter addresses the design of castings to reduce the occurrence of internal shrinkage. It provides a detailed discussion on design considerations for molding, cleaning, machining, and function.

The nonferrous alloys described in this chapter include aluminum and aluminum alloys, copper and copper alloys, titanium and titanium alloys, zirconium and zirconium alloys, and tantalum and tantalum alloys. Some of the factors that affect the corrosion performance of welded nonferrous assemblies include galvanic effects, crevices, assembly stresses in products susceptible to stress-corrosion cracking, and hydrogen pickup and subsequent cracking. The emphasis is placed on the compositions, general welding considerations, and corrosion behavior of these alloys.