This article describes the characteristics of thermoplastic composites and its material forms. It presents the steps and considerations in manufacturing the thermoplastic composites. The article describes the various techniques of manufacturing, such as consolidation, autoclave molding, diaphragm forming, compression molding, roll forming, bladder molding, liquid molding, filament winding, and pultrusion.

Advanced thermoplastic composites possess impact resistance, fracture toughness, and elevated temperature endurance properties due to their melt-fusible nature. This article presents the material options available for thermoplastic composites such as pseudothermoplastics, post-impregnated thermoplastics, and true thermoplastics. It describes the processing methods of thermoplastic composites, including weaving, seaming, autoclaving, preconsolidation, roll consolidation, roll forming/pultruding, thermoforming, press forming, hydroforming, and diaphragm forming. The article provides information on different types of joints, namely, fastened, adhesive bonded, dual polymer bonded, co-consolidated, and welded joints. It explains the joining methods of thermoplastic composites, such as press forming, diaphragm forming, autoclaving, ultrasonic welding, resistance welding, and induction welding.

This article briefly describes the production of beryllium powder and beryllium/beryllium oxide metal-matrix powder. It discusses fully dense consolidation methods: vacuum hot pressing, hot isostatic pressing, and cold isostatic pressing. Secondary fabrication operations of beryllium and aluminum-beryllium alloys such as extrusion, rolling, welding, joining, and machining are discussed. The article discusses quality control and provides information on the structural, optical, and high-purity grades of beryllium.

This article discusses two major sintering methods: pressureless and pressure-assisted sintering. Pressureless sintering techniques include vacuum and partial-pressure, hydrogen, and microwave sintering. Pressure-assisted consolidation techniques include overpressure sintering, sintering followed by postsinter hot isostatic pressing, hot pressing, and several rapid hot consolidation techniques. The article describes nitrogen sintering and the sintering of cermets. It reviews the furnaces used for sintering and presents the lubrication removal techniques. The article also outlines the need to control carbon and oxygen to obtain optimal properties and explains microstructure development and grain size control.

This article discusses the applications of high-strength aluminum powder metallurgy (P/M) alloys, detailing the advantages, properties, and the various steps involved in P/M technology, including powder production, powder processing, and degassing and consolidation. Three areas of design efforts to push the inherent advantages of aluminum alloys to new limits are also covered: high ambient-temperature strength with improved corrosion and stress corrosion cracking resistance; improved elevated-temperature properties so aluminum alloys can more effectively compete with titanium alloys; and increased stiffness and/or reduced density for aluminum alloys to compete with organic composites. An appendix provides a detailed account of the properties, processing, and applications of conventionally pressed and sintered aluminum P/M alloys.

This article provides information on the thermoplastic resins used as matrix materials for continuous fiber reinforced composites. It focuses on the materials that are suitable for fabrication of structural laminates and used for aerospace applications. The article provides a discussion on the background, categories, characteristics, product forms, properties, cost benefits, and processing techniques of thermoplastic resins. Strategies that have been advanced to deal with impregnation difficulties are also discussed.

This article provides a basic introduction to the various aspects of full density powder metallurgy, including properties, applications, processing methods, and process parameters.

Designing composites for structural performance initially involves meeting a set of desired performance specifications at a minimum cost. This article discusses the factors that are considered in designing the manufacturing of polymeric composites. It describes the various aspects of manufacturing, forming process, and post-processing and fabrication for designing the composites.

Metal-matrix composites (MMCs) are a class of materials with a wide variety of structural, wear, and thermal management applications. This article discusses the primary processing methods used to manufacture discontinuous aluminum MMCs, namely, high-pressure die casting, pressure infiltration casting, liquid metal infiltration, spray deposition, and powder metallurgy methods. It describes the processing of continuous fiber-reinforced aluminum, discontinuously, reinforced titanium, and continuous fiber-reinforced titanium. The article concludes with information on work done to develop magnesium, copper, and superalloy MMCs.

The goal of design is to improve the overall performance of the metal or ceramic matrix rather than to create a material with different response than the base matrix. This article focuses on the design for manufacturing polymeric composites. Specially developed methods including contact molding, compression-type molding, resin-injection molding, and pultrusion are described. The article also discusses the various factors to be considered in designing for composite manufacturing.

This article provides an overview of the composition and properties of powder metallurgy (P/M) aluminum powders for pressed and sintered parts. It includes the steps involved in the processing of high-performance P/M alloys. The article describes the classes of high-performance P/M alloys, including corrosion-resistant alloys (stress-corrosion cracking), elevated-temperature alloys, and low density/high-stiffness alloys.

Open molding is the method used in the polymer-matrix composites industry to make thermoset composite products. This article discusses the advantages, disadvantages, and applications of the open molding. It describes the various process of the open molding, such as hand lay-up process and spray-up process. Workmanship for hand lay-up and spray-up processes is reviewed. The article provides information on the matrix-resin materials used for open molding, including unsaturated polyester resins, epoxy vinyl ester resins, and reinforcements. It explains the component design and short- and long-term properties of a fiber reinforced composite laminate depending on material selection and workmanship. The article also presents the basic design guidelines for open molding.

Beryllium possesses an unusual combination of physical and mechanical properties, suiting it for specialized applications where its relatively high cost can be justified. It has very low density, a moderately high melting point, high elastic modulus, and good electrical and thermal conductivity. The article describes structural, instrument, and optical grade beryllium and the corresponding compositional ranges. It also discusses processing and product forms as well as factors affecting corrosion resistance. The article concludes with a short note on health and safety considerations when handling beryllium.

Electrical contacts are made of elemental metals, composites, or alloys that are made by the melt-cast method or manufactured by powder metallurgy (PM) processes. PM facilitates combinations of metals that ordinarily cannot be achieved by alloying. This article describes the processing, properties, and performance of electrical contacts based on PM or hybrid composite technologies with refractory metals and compounds. These metals and compounds include tungsten, molybdenum, carbide-based composites, and silver-base composites. The article explains composite manufacturing methods, namely, PM methods, internal oxidation, and hybrid consolidation. The availability of the refractory metals and compounds in various product forms are also reviewed.

Beryllium is a metal with an unusual combination of physical and mechanical properties that make it particularly effective in optical components, precision instruments, and specialized aerospace applications. Almost all of the beryllium in use is a powder metallurgy (P/M) product. Beginning with an overview of the mining and refining processes of beryllium, this article discusses powder production and consolidation methods, beryllium grades and their designations, and the protective measures that have been enacted to reduce exposure to beryllium.

This article focuses on the properties of conventional wrought superalloys based on nickel, iron, and cobalt, as well as on the properties of alloys produced from powder. The powder metallurgy (P/M) category includes alloys that were originally developed as casting alloys; new alloy compositions developed specifically to benefit from powder processing; and oxide dispersion strengthened alloys (particularly those produced by mechanical alloying). The article discusses some of the applications of superalloys and emphazises the interplay between chemical composition, microstructure, consolidation method, mechanical properties and surface stability of wrought nickel alloys. Vacuum melting processes are a necessity for many nickel- and iron-nickel-base alloys because of the presence of aluminum and titanium as solutes. Cobalt-base alloys do not usually contain these elements and may be melted in air. An appendix to this article presents the property data and corresponding information on a family of cobalt-chromium-tungsten-carbon alloys that use P/M processing.

Oxide dispersion-strengthened (ODS) alloys are produced by mechanical alloying, a process by which base metals and alloying particles are powdered together forming a metal-matrix composite. This article discusses the production of ODS superalloy powders and subsequent processing steps, including consolidation, hot rolling, heat treating, and the fabrication of mill products. It also discusses the nominal composition and microstructure of commercial ODS alloys, including nickel, iron, and aluminum-base systems, and provides detailed information on their mechanical, physical, oxidation, and hot-corrosion properties.

Microstructural analysis of the composite matrix is necessary to understand the performance of the part and its long-term durability. This article focuses on the microstructural analysis of engineering thermoplastic-matrix composites and the influence of cooling rate and nucleation on the formation of spherulites in high-temperature thermoplastic-matrix carbon-fiber-reinforced composites. It also describes the microstructural analysis of a bio-based thermosetting-matrix natural fiber composite system.

This article provides information on the microstructure of powder metal alloys and the special handling requirements of porous materials. It covers selection, sectioning, mounting, grinding, and polishing, and describes procedures, such as washing, liquid removal, and impregnation, meant to preserve pore structures and keep them open for analysis. The article compares and contrasts the microstructures of nearly 50 powder metal alloys, using them to illustrate the effect of consolidation and compaction methods as well as particle size, composition, and shape. It discusses imaging equipment and techniques and provides data on etchants and etching procedures.