The design of forging operations; consisting of dies, fixturing, and parts; requires a consistent and unambiguous method for representing critical dimensions and tolerances. This article presents a dimensioning process, based on tooling points and datum planes, with the potential to simplify geometries while minimizing tolerance stack-ups. The method also facilitates inspection liaison between vendors and users because fixturing is easy to duplicate and tooling points are consistent from forging to finish-machined part. The article focuses on the most common dimensional tolerances for closed-die forgings, including finish allowances for machining, length and width tolerances, die-wear tolerance, match tolerances, die-closure or thickness tolerances, straightness and flatness tolerances, radii tolerances, flash-extension tolerances, and surface tolerances. It also contains a convenient summary in the form of a checklist.

Solid modeling is the act of creating the three-dimensional models of various components and system using a computer-aided design (CAD) tool. This article describes the fundamental approaches of solid modeling, such as manufacturing operation simulation, parametric approach, and reference entities. It discusses the application of solid modeling systems to create expressions or variables and various surfaces for components. The use of high-end CAD systems to afford a number of sheet metal functions is reviewed. The article explains the explicit-parametric modeling and model verification for the solid modeling. It provides information on the application of solid modeling in associativity and concurrent engineering, product lifecycle management, and collaborative engineering.

This article provides a discussion on ten rules for the effective production of reliable castings. These rules include good-quality melt, liquid front damage, liquid front stop, bubble damage, core blows, shrinkage damage, convection damage, segregation, residual stress, and location points.

As additive manufacturing (AM) gains maturity as a manufacturing technique for production in many industrial sectors, inspection as a tool for quality control gains importance. This article is focused on the field of dimensional metrology, which is typically concerned with the verification of size, location, form, and surface topography of geometric features. This is split into two categories: geometric (size, location, form) and surface measurement (topography). The article also focuses on applicable inspection technologies, and it discusses the context within digital thread manufacturing. A case study on the Digital Inspection Requirements Enhancing Coverage and Traceability (DIRECT) is also presented.

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.

Machining of cast iron involves removing metal from the cast part, usually by cutting with a power-driven machine tool. This article discusses the factors that influence machinability, the methods used to evaluate machinability of cast irons, the effects of cast iron microstructure on cutting tool life, and the importance of as-cast surface integrity on the machining variation. It presents examples of cutting tool materials selection for different cast iron grades, and describes the effects of coolants on the machining of cast irons. A chart showing different cutting materials and cutting speed ranges for selected iron-carbon alloys is also presented. Different types of cutting tool wear observed during turning are schematically illustrated.

Flanging is a process used to form a projecting rim or edge on a part. This article explores how to determine aluminum flanging limits in terms of fracture, wrinkling, and springback, and their influencing material and process parameters with examples.

Mechanical properties are often the most important properties in the design and selection of engineering plastics. Temperature, molecular structure, crystallinity, viscoelasticity, and effects of environment, fillers and reinforcements are considered as the basic factors affecting the mechanical properties of engineering plastics. The testing methods for determining mechanical properties, including stress-strain test, modulus-directed tensile test, strength test, strength-directed tensile test, impact test, and dynamic mechanical test are discussed.

This article provides an overview of the finite-element-based analyses (FEA) of advanced composite structures and highlights key aspects such as the homogenization of materials properties and post-processing of numerical results. It discusses the analysis of composite structures based on micromechanics and macromechanics. The article describes the FEA of 3-D solid elements, 2-D cylindrical shell elements, and 1-D beam elements. It contains a table that lists the commercially available finite element codes related to the analysis of fibrous composite materials. The article presents classical examples of the mechanics of composite materials to illustrate the aspects of multilayered composite structures.

Modern, solids-based computer-aided design/computer-aided manufacturing (CAD/CAM) systems provide a good share of what is needed for companies to develop products using modern methods. This article provides a brief history and an overview of CAD technology. Form features combined with constraint parameters have greatly simplified how designers work with solid modelers to design parts and assemblies. The article describes four types of constraints: numeric, geometric, algebraic, and attributes. It presents a discussion on data associativity and assembly design used in CAD system. The article provides information on the applications of CAD systems, including integrated product development, drafting and product documentation, product visualization, mechanical analysis, and numerical control programming.

This article is a compilation of definition of terms related to materials selection and its integration with engineering design processes.

This article briefly introduces some commonly used methods for mechanical testing. It describes the test methods and provides comparative data for the mechanical property tests. In addition, creep testing and dynamic mechanical analyses of viscoelastic plastics are also briefly described. The article discusses the processes involved in the short-term and long-term tensile testing of plastics. Information on the strength/modulus and deflection tests, impact toughness, hardness testing, and fatigue testing of plastics is also provided. The article describes tension testing of elastomers and fibers. It covers two basic methods to test the mechanical properties of fibers, namely the single-filament tension test and the tensile test of a yarn or a group of fibers.

This article discusses the use of a shaped electrode for electrical discharge machining (EDM). It describes the operational methodology of the EDM. Topography, metallurgical and chemical effects, and surface integrity of the EDM surface are reviewed. The article provides information on the characteristics of electrodes and the process features of electrode manufacturing. Functions of the dielectric fluids and applications of the EDM are discussed. The article reviews the advancement in EDM such as no-wear EDM and computer numerically controlled vertical EDM. It analyzes the applications and process of the traveling wire EDM. Health and safety measures for the EDM process are also discussed.

Casting offers a great amount of component design flexibility. This article discusses six casting design parameters that drive the geometry of casting design from a process standpoint. It provides information on the design of junctions and addresses considerations of secondary operations in design. The article describes the factors that control casting tolerances and presents specific tips for designing castings with uniform wall thickness, unequal sections, thin sections, economical coring, functional packaging, and core design. The article provides a framework for analyzing all manners of manufacturing as possible conversion candidates for casting. It concludes with a discussion on different metalcasting design projects.

This article describes how design can unfavorably affect product quality. It provides information on the total quality management philosophy, emphasizing the principles of quality management. The article discusses various methods for evaluating a product design for quality. It presents design guidelines that are intended to provide products with a potential for higher levels of quality.

This article begins with a discussion on the effects of alloying and impurity elements on the properties of aluminum cast alloys and their chemical compositions. It describes the various means of structural control, namely, chemistry control, control of element ratios based on the stoichiometry of intermetallic phases, and control of solidification conditions. The article discusses the modification and grain refinement of aluminum-silicon alloys by the use of modifiers and refiners to influence eutectic and hypereutectic structures in aluminum-silicon alloys. It provides information on foundry alloys for specific casting applications. The article concludes with a discussion on the heat treatment practices and properties of aluminum casting alloys.

This article reviews the pattern materials used in investment casting, which can be loosely grouped into waxes and plastics. The patternmaking process, pattern tooling, and pattern and cluster assembly are described. The article also describes the manufacture of ceramic shell molds and cores, detailing the binders and other materials used, as well as the formulation and control of slurries. Methods for pattern removal, mold firing, melting, casting, postcasting treatment, and inspection are explained. After presenting design recommendations for investment castings, the article concludes with information on applications and special versions of the investment casting process.

This article describes the presses that are mechanically or hydraulically powered and used for producing sheet, strip, and plate from sheet metal. It also presents the JIC standards for presses, compares the presses based on power source, details the selection criteria and provides information on the various drive systems and the auxiliary equipment. It describes the selection of die materials and lubricants for sheet metal forming and provides information on the lubrication mechanisms and selection with a list of lubricant types for forming of specific sheet materials of ferrous or nonferrous metals. The article reviews the various types of forming processes such as blanking, piercing, fine-edge blanking, press bending, press forming, forming by multiple-slide machines, deep drawing, stretch forming, spinning, rubber-pad forming, three-roll forming, contour roll forming, drop hammer forming, explosive forming, electromagnetic forming, and superplastic forming.