Braided structures are unique in their high level of conformability, torsional stability, and damage resistance. This article describes the classifications of braiding such as two-dimensional braiding and three-dimensional braiding. It presents the governing equations for computer-controlled braiding in a table. The article lists the applications of braided fabrics and composites. It discusses the formation, structure, and properties of two-dimensional braid composites and three-dimensional braid composites: the damage tolerance and the impact damage limitation.

Braiding is a textile process that is known for its simplicity and versatility. Braided structures are unique in their high level of conformability, torsional stability, and damage resistance. This article describes the braiding process and the mechanical properties of two-dimensional and three-dimensional braiding.

High-temperature-resistant polymers are used in aerospace, electronic, and other applications that demand outstanding elevated-temperature physical and mechanical properties. This article discusses the general characteristics of condensation-type polyimides and polymerization of monomer reactants (PMR) polyimides. It provides information on the applications of PMR-15 with illustrations.

Affordability is the key issue facing design engineers and manufacturers of composite components for current and next-generation aircraft, spacecraft, propulsion systems, and other advanced applications. This article describes the software tools available for modeling and analyzing costs associated with design and manufacturing options for advanced composites programs. It presents an example of a composite exhaust nozzle shroud where the design and manufacture options were analyzed and adjusted, based on the use of cost analysis tools. The article also lists some of the attributes found in various cost modeling software and the potential cost benefits.

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.

This article discusses the historical background of composite construction in recreational equipment and sporting goods. It provides information on the applications of composites in baseball bats, tennis rackets, and golf clubs. The applications of composites in bicycling, winter sports, aquatic sports, track, field, and archery equipment are also discussed.

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 describes the interaction of composition, manufacturing process, and composite properties of composites. The manufacturing process includes resin-matrix, metal-matrix, and carbon/carbon matrix processing. The article discusses various mechanical properties of composites. It explores how variations in the composition, manufacturing, shop process instructions, and loading/environmental conditions can affect the use of a composite product in a performance/service life operation.

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.

This article provides a summary of the concepts discussed in the articles under the Section “Constituent Materials” in ASM Handbook, Volume 21: Composites. The Section describes the major matrix resins and reinforcing fibers used in composite materials, as well as some of the intermediate material forms available for composite fabrication.

Resin transfer molding and structural reaction injection molding belong to a family, sometimes denoted as liquid composite molding. This article provides information on the characteristics and automotive and aerospace applications of liquid composite molding. It reviews techniques that use hard tooling and positive (superatmospheric) pressures to produce structures. The techniques include vacuum-assisted resin injection, vacuum infusion, resin-film infusion, and injection-compression molding. The article provides an overview of the materials that are commonly used together with some of processing characteristics that are important to processing speed and part quality. It concludes with a discussion on design guidelines for the liquid composite molding.

For the reinforcement of metal-matrix composites, four general classes of materials are commercially available: oxide fibers based primarily on alumina and alumina silica systems, nonoxide systems based on silicon carbide, boron fibers, and carbon fibers. This article discusses the key aspects of aluminum oxide fibers, silicon carbide fibers, boron fibers, and carbon fibers. The commercial fibers for reinforcement of metal-matrix composites are presented in a table. A tabulation of the coating schemes for silicon carbide monofilament fibers is also provided.

This article presents the importance of progressing from post-manufacturing inspection/verification to in-process inspection/verification methods. It lists the various quality assurance factors considered for typical composite laminate lay-up process. The article provides information on composite cure tooling that is fabricated from steel, aluminum, or high-temperature composite materials. The quality assurance for commercial applications is reviewed. The article concludes with a discussion on data fusion systems designed to provide nondestructive analysis data from fabrication and assembly processes for each individual composite part.

Resin transfer molding (RTM) and structural reaction injection molding (SRIM) are two similar processes that are well suited to the manufacture of large, complex, and high-performance structures. This article discusses the similarities and differences of RTM and SRIM processes and the unique design considerations with respect to the physical properties, geometry, surface quality, process economics, equipment, and tooling of a component that should be considered in choosing RTM or SRIM over other competing processes for fabricating reinforced components.

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.

This article describes common design criteria and identifies the design considerations that have a significant effect on the end product. The design criteria include cost, size, mechanical properties, repeatability and precision of parts, damage tolerance and durability, and environmental constraints.

This article describes the types of fabrics and preforms used in the manufacture of advanced composites and related selection, design, manufacturing, and performance considerations. The types of fabrics and preforms include unidirectional and two-directional fabrics; multidirectionally reinforced fabrics; hybrid fabrics; woven fabric prepregs; unidirectional and multidirectional tape prepregs; and the prepreg tow. The article discusses three major categories of tape manufacturing processes, namely, the hand lay-up, machine-cut patterns that are laid up by hand, and the automatic machine lay-up. It provides a description of the two classes of prepregs. These include those that are suitable for high-performance applications and suitable for lower-performance molding compounds.

Corrosion is the deterioration of a material by a reaction of that material with its environment. The realization that corrosion control can be profitable has been acknowledged repeatedly by industry, typically following costly business interruptions. This article describes the electrochemical nature of corrosion and provides the typical analysis of environmental- and corrosion-related failures. It presents common methods of testing of laboratory corrosion and discusses the processes involved in the prevention of environmental- and corrosion-related failures of metals and nonmetals.

Physically, tantalum is a dark, blue-gray, lusterless metal that exists in two crystalline forms: an alpha-phase with a body-centered cubic structure, and a brittle beta-phase with a tetragonal orientation. This article tabulates the physical and material properties of tantalum. It discusses the use of tantalum in medical electronics and the advantage of tantalum over stainless steel. The article describes the manufacturing and medical applications of tantalum foam.