This chapter is a detailed account of various attributes related to mixing and testing of powder-binder feedstocks. Mixing parameters and their effects on feedstock properties is discussed. The attributes reviewed include mixture homogeneity, wetting, powder-binder ratio, feedstock density, elastic modulus, rheological behavior, particle size, formulation control, feedstock mixing, and feedstock properties. The chapter also provides information on the processes involved in feedstock preparation and testing.

This chapter includes a comprehensive set of definitions used in powder-binder processing.

The conversion of feedstock into a shape involves the application of heat and pressure, and possibly solvents. This chapter discusses the operating principle, advantages, limitations, and applications of such shaping processes, namely additive manufacturing, cold isostatic pressing, die compaction, extrusion, injection molding, slip casting, slurry processes, and tape casting. Information on equipment setup, requirements, and the various factors influencing these processes are described. In addition, the chapter provides information on novel approaches and processing costs applicable to these shaping processes.

This chapter provides an introduction to powder processing of binders and polymers. It sets the context for the remainder of the book by providing an overview of the topics discussed in the subsequent chapters and by providing introduction to powder-binder fabrication and customization of feedstock and describing the challenges in component production. The chapter also summarizes alphabetically a few key concepts in powder-binder processing.

This chapter discusses the methods by which stainless steel powders are shaped and compacted prior to sintering, including rigid die compaction, metal injection molding, extrusion, and hot isostatic pressing. It explains where each process is used and how processing parameters, such as temperature and pressure, and powder characteristics, such as particle size and shape, influence the quality of manufactured parts. It describes the various stages of metal powder compaction, the role of lubricants, and how to account for dimensional changes in the design of tooling and process sequences.

This chapter is intended to identify materials, processes, and designs that will lead to great advances in powder-binder forming technologies. It discusses some of the structures obtained through these advances in powder-binder technologies such as binder jetting and extrusion-based additive manufacturing, including bound-metal deposition and fused-filament fabrication: oxidation-resistant high-temperature alloys, anisotropic structures, submicrometer-scale structures, surface hard materials, and artist metallic clays. Some of the advances discussed include the developments in process involving plastics, emulsions, ceramics, and porous structures and foams. Improvements in the design processes have led to the development of functional structures, controlled porosity, and bioinspired structures.

This chapter provides details on powder-binder processing for three materials, namely precipitation-hardened 17-4 PH stainless steel, cemented carbides, and alumina. The types of powders, binders, feedstock, shaping processes, debinding, sintering cycles, compositions, microstructure, distortion, postsintering treatments, and mechanical properties are presented for each. The shaping options include powder-binder approaches such as binder jetting, injection molding, extrusion, slip and slurry casting, centrifugal casting, tape casting, and additive manufacturing. Sintering options are outlined with respect to attaining high final properties.

Generally, binders consist of at least three ingredients: a backbone to provide strength (compounds such as polyethylene, polypropylene, ethylene vinyl acetate, and polystyrene); a filler, such as polyacetal and paraffin wax, to occupy space between particles; and additives, such as stearates, stearic acid, or magnesium stearate, as well as phosphates and sulfonates, to adjust viscosity, lubricate tooling, disperse particles, or induce binder wetting of the powder. In the case of binders deposited via ink jet printing, the binder contains solvents to lower the viscosity for easier jetting. The chapter provides a detailed description of these constituents. The requirements of a binder as well as the factors determining the physical and thermal properties of polymers are discussed. Then, two factors associated with solvation of polymers, namely solubility parameter and wetting, are covered. The chapter ends with information on the specification of polymers used in binders.

Cold spray coatings technology has the potential to provide surface enhancement for applications in sectors such as defense and aerospace, oil and gas, power generation, medical, automotive, electronics, and railways. The ability to deposit clean metallic coatings is used in applications requiring corrosion/oxidation protection, erosion/wear protection, additive manufacturing, and fabricating free forms. This chapter discusses the function, advantages, and benefits of some of these applications.

This chapter provides details on several specific binder formulations and a discussion of basic binder design concepts. The focus is on customization of the feedstock response to heating, pressurization, or solvent exposure for a specific shaping process. The discussion starts with the requirements of a binder system, the historical progression of binder formulations, and the use of binder alternatives to adapt to specific applications. The importance of binder handling strength to shape preservation is emphasized. The chapter provides information on the binders used for room-temperature shaping, namely slurry and tape casting systems.

This chapter describes various units and process streams that are often susceptible corrosion inhibitors in crude oil refineries, discusses the types and applications of corrosion inhibitors, and provides some information on corrosion monitoring techniques used at refineries.

This article summarizes the results of work completed by the ASM Thermal Spray Society Advisory Committee to identify key research challenges and opportunities in the thermal spray field. It describes and prioritizes research priorities related to emerging process methods, thermal spray markets and applications, and process robustness, reliability, and economics.

This chapter discusses the application of high-pressure cold spray to the automotive industry field, with special attention to three applications: additive manufacturing, fabrication methods, and protective coatings. Various studies on the automotive application of cold spray are reviewed. The background and purpose of each application are presented and practical cases are discussed.

This appendix is a compilation of terms and definitions associated with the processing, microstructure, and properties of powder metal stainless steels.

This chapter introduces the key powder fabrication attributes to assist in the identification of the right powders for an application. First, it describes the characteristics of engineering powders such as particle size distribution, powder shape and packing density, surface area, powder flow and rheology, and chemical analysis. The chapter then describes the general categories of powder fabrication methods, namely mechanical comminution, electrochemical precipitation, thermochemical reaction, and phase change and atomization. It provides information on the two largest contributors to powder price, namely raw material cost and conversion cost. The applicability of various processes to specific material systems is mentioned throughout this chapter.

Plastic gears are continuing to displace metal gears in applications ranging from automotive components to office automation equipment. This chapter discusses the characteristics, classification, advantages, and disadvantages of plastics for gear applications. It provides a comparison between the properties of metals and plastics for designing gears. The chapter reviews some of the commonly used plastic materials for gear applications including thermoplastic and thermoset gear materials. The chapter also describes the processes involved in plastic gear manufacturing.

This chapter covers the practices and procedures used for shape casting metals and alloys. It begins with a review of the factors that influence solidification and contribute to the formation of casting defects. It then describes basic melting methods, including induction, cupola, crucible, and vacuum melting, and common casting techniques such as sand casting, plaster and shell casting, evaporative pattern casting, investment casting, permanent mold casting, cold and hot chamber die casting, squeeze casting, semisolid metal processing, and centrifugal casting.