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This chapter familiarizes readers with the machining characteristics of titanium and the implementation of machining and shaping processes. It explains why titanium alloys are more difficult to machine than other metals and how it impacts the equipment and procedures that can be used. It describes the basic machining requirements for titanium in terms of tool geometry and materials, machine setup rigidity, cutting speeds and feed rates, and surface conditions, and explains how the requirements are met in practice in milling, turning, drilling, surface grinding, and broaching operations. The chapter also covers chemical and electrochemical machining processes as well as flame cutting.

Beryllium’s machining characteristics are similar to those of heat-treated cast aluminum and chilled cast iron. Like the other materials, it can be turned, milled, drilled, bored, sawed, cut, threaded, tapped, and trepanned with good results. This chapter explains how these machining operations are conducted and describes the effect of tooling materials, cutting speeds, metal-removal rates, and other variables. It also explains how to assess and remove surface damage caused by machining such as microcracks and twins.

In contrast to most plastic deformation processes, the shape of a machined component is not uniquely defined by the tooling. Instead, it is affected by complex interactions between tool geometry, material properties, and frictional stresses and is further complicated by tool wear. This chapter covers the mechanics and tribology of metal cutting processes. It discusses the factors that influence chip formation, including tool and process geometry, cutting forces and speeds, temperature, and stress distribution. It reviews the causes and effects of tool wear and explains how to predict and extend the life of cutting tools based on the material of construction, the use of cutting fluids, and the means of lubrication. It presents various methods for evaluating workpiece materials, chip formation, wear, and surface finish in cutting processes such as turning, milling, and drilling. It also discusses the mechanics and tribology of surface grinding and other forms of abrasive machining.

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 appendix provides an extensive amount of data corresponding to titanium machining processes, including sawing, turning, drilling, reaming, tapping, broaching, face milling, end milling, slotting, surface grinding, and thermal cutting.

This chapter covers the practical aspects of machining, particularly for turning, milling, drilling, and grinding operations. It begins with a discussion on machinability and its impact on quality and cost. It then describes the dimensional and surface finish tolerances that can be achieved through conventional machining methods, the mechanics of chip formation, the factors that affect tool wear, the selection and use of cutting fluids, and the determination of machining parameters based on force and power requirements. It also includes information on nontraditional machining processes such as electrical discharge, abrasive jet, and hydrodynamic machining, laser and electron beam machining, ultrasonic impact grinding, and electrical discharge wire cutting.

The qualities that make superalloys excellent engineering materials also make them difficult to machine. This chapter discusses the challenges involved in machining superalloys and the factors that determine machinability. It addresses material removal rates, cutting tool materials, tool life, and practical issues such as set up time, tool changes, and production scheduling. It describes several machining processes, including turning, boring, planing, trepanning, shaping, broaching, drilling, tapping, thread milling, and grinding. It also provides information on toolholders, fixturing, cutting and grinding fluids, and tooling modifications.

This chapter presents a qualitative and quantitative overview of the stresses, strains, forces, and energy associated with metalworking processes and the tribological behavior of metals. It covers key concepts necessary for understanding metalworking tribology, including plastic deformation, yield criteria, flow strength, and the application of flow rules. It explains how to calculate the work involved in deformation processes, how to assess the propensity for fracture, how to determine temperature rise and strain distribution in the workpiece, and how to classify metalworking processes based on related tribology.

This chapter is a detailed account of the general characteristics and effects of and the methods for preventing or reducing different categories of wear failures, namely abrasive (erosive, grinding, and gouging), adhesive, and fretting wear.

This chapter discusses the causes and effects of wear along with prevention methods. It covers abrasive, erosive, erosion-corrosion, grinding, gouging, adhesive, and fretting wear. It also discusses various forms of contact-stress fatigue, including subsurface-origin fatigue, surface-origin fatigue, subcase-origin fatigue (spalling fatigue), and cavitation fatigue.

Titanium is a lightweight metal used in a growing number of applications for its strength, toughness, stiffness, corrosion resistance, biocompatibility, and high-temperature operating characteristics. This chapter discusses the applications, metallurgy, properties, compositions, and grades of commercially pure titanium and alpha and near-alpha, alpha-beta, and beta titanium alloys. It describes primary and secondary fabrication processes, including melting, forging, forming, heat treating, casting, machining, and joining as well as powder metallurgy and direct metal deposition. It also compares and contrasts the properties of wrought, cast, and powder metal titanium products and discusses corrosion behaviors.

This chapter is a study of the microstructure of case-hardened steels. It explains what can be learned by examining grain size, microcracking, nonmetallic inclusions, and the effects of microsegregation. It identifies information-rich features, describing their ideal characteristics, the likely cause of variations observed, and their effect on mechanical properties and behaviors. The discussions throughout the chapter are aided by the use of images, diagrams, data plots, and tables.

This chapter discusses the melting and conversion of superalloys and the solidification challenges they present. Superalloys have high solute content which can lead to untreatable defects if they solidify too slowly. These defects, called freckles, are highly detrimental to fatigue life. The chapter explains how and why freckles form as well as how they can be prevented. It describes the criteria for selecting the proper melting method for specific alloys based on melt segregation and chemistry requirements. It compares standard processes, including electric arc furnace/argon oxygen decarburization melting, vacuum induction melting, vacuum arc remelting, and electroslag remelting. It also addresses related issues such as consumable remelt quality, control anomalies, melt pool characteristics, and melt-related defects, and includes a section that discusses the processes involved in converting cast ingots into mill products.

Drawing is a bulk deformation process that involves significant surface generation and high pressures. This chapter provides an overview of the mechanics and tribology of wire, bar, tube, and shape drawing. It presents important equations for calculating stresses, forces, friction, heat, strain, and distortion for different tooling configurations and geometries. It explains how to select and apply lubricants based on drawing speed, die design, and other factors and how to maintain sufficient film thickness for hydrodynamic, mixed, and solid-film lubrication conditions. It also discusses the use of vibrating dies, the influence of surface finish and defects, and lubrication practices for specific materials.

The low-pressure permanent molding (LPPM) and semipermanent molding (LPSPM) processes are versatile, and they meet the quality requirements of a variety of high-integrity, large-sized, and thin-walled aluminum castings for various industries. This chapter presents the major features, operation sequence, advantages, and applications of LPPM, LPSPM, and counter-pressure casting.

This chapter presents definitions of terms related to the metallurgy and metallographic study of irons and steels.

This chapter covers a wide range of finishing and coating operations, including cleaning, honing, polishing and buffing, and lapping. It discusses the use of rust-preventative compounds, conversion coatings, and plating metals as well as weld overlay, thermal spray, and ceramic coatings and various pack cementation and deposition processes. It also discusses the selection and use of industrial paints and paint application methods.

This chapter examines the surface interactions that occur during metal forming operations at both the macroscopic and microscopic scale. It describes the measurement and characterization of surface profiles based on form error, waviness, and roughness. It explains how workpiece surfaces become rougher or smoother due to the effects of deformation, tooling interactions, and lubricant film thickness. It familiarizes readers with the concept of nominal contact, the role of asperities, and the effects of interface pressure, plasticity index, shear stress, and bulk strain rate. It also reviews the two basic friction rules applicable to metal forming and presents advanced friction models that account for the transition between Coulomb and Tresca behavior and the effects of lubrication.