This article describes glass fibers derived from silica, alumina, and calcium oxide compositions. The section on general-purpose glass fibers provides an in-depth discussion of melt properties, fiber properties, methods of manufacture, and significant product types. The article discusses special-purpose glass fibers and reviews compositions, manufacture, properties, and applications to an extent commensurate with their commercial use. It addresses the generic glass melting and fiber forming process, including the viscosity-versus-temperature profile required for general-purpose E-glass fibers with and without boron. The article also discusses continuous multiend or single-end roving, woven roving (or noncrimp fabrics), fiberglass mats, chopped strands, and yarns for textile applications.

This article examines the factors that influence the development of high-performance aramid fibers and other synthetic high-performance fibers. It highlights the importance of suitable monomers, solvents, and fiber processing conditions. The focus is on the technical aspects of the value proposition and the key properties of aramid materials that determine their suitability for specific applications. The article also provides a brief overview of the wide range of both established and emerging applications of aramid materials.

This article discusses the array of fiber products, manufacturing approaches, and production suppliers. It also discusses carbon fibers, their range of uses, and their performance capabilities, which are unique and separate from oxide and non-oxide fibers. The article reviews the history of developing silicon carbide (SiC) fibers and SiC-base ceramic-matrix composites. CMCs provide a roadmap and timeline for the technologies developed and refined over the last 50 years of effort to make SiC-SiC composites a reality. The article also describes the use of fiber in composite applications.

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.

Engineering plastics, as a general class of materials, are prone to the development of internal stresses which arise during processing or during servicing when parts are exposed to environments that impose deformation and/or temperature extremes. Thermal stresses are largely a consequence of high coefficients of thermal expansion and low thermal diffusivities. Although time-consuming techniques can be used to analyze thermal stresses, several useful qualitative tests are described in this article. The classification of internal stresses in plastic parts is covered. The article describes the effects of low thermal diffusivity and high thermal expansion properties, and the variation of mechanical properties with temperature. It discusses the combined effects of thermal stresses and orientation that result from processing conditions. The article also describes the effect of aging on properties of plastics. It explains the use of high-modulus graphite fibers in amorphous polymers.

This article describes the features, benefits and limitations of petrolatum and microcrystalline wax. It provides a detailed discussion on the steps to be followed before applying the various forms of the wax-based coatings. The wax-based coating forms include petrolatum and microcrystalline tapes, marine petrolatum-based pile systems; cold-applied petrolatum-based paste coating systems; hot-applied microcrystalline wax flood coating systems; wax-based dips, brushons, and sprays; and wax-impregnated fabrics and wax-coated papers. The article also discusses the applications and limitations of these wax-based coatings. It concludes by highlighting the steps involved in the installation of wax-based casing fillers.

Furnaces are one of the most versatile types of industrial appliances that span many different areas of use. This article discusses the classification of various furnaces used in heat treating based on the mode of operation (batch-type furnaces and continuous-type furnaces), application, heating method, mode of heat transfer, type of materials handling system, and mode of waste heat recovery (recuperation and regeneration). It provides information on uniform temperature distribution, the general requirements and selection criteria for insulation materials, as well as the basic safety requirements of these furnaces.

The optical fiber preform is a long cylinder of glass that contains core and cladding glasses. This article describes the relationship between the peak furnace temperature, fiber draw tension, and fiber draw speed. It focuses on temperature requirements such as product viscosity, hot zone length, temperature profile, and heating cycle to draw the glass. The article provides information on process gases in the draw induction furnace, insulation package for induction heating operations, and furnace design and scalability. It reviews the key factors for the selection of susceptor materials, namely, cost, temperature cycling, and the impact on the product.

This article focuses on the various types of corrosion-related failure mechanisms and their effects on passive electrical components. The types include halide-induced corrosion, organic-acid-induced corrosion, electrochemical metal migration, silver tarnish, fretting, and metal whiskers. The passive electrical components include resistors, capacitors, wound components, sensors, transducers, relays, switches, connectors, printed circuit boards, and hardware.

This article discusses the influence of the materials, design, package type, and environment on corrosion in microelectronics. It describes the common sources and mechanisms of corrosion in microelectronics, including anodic, cathodic, and electrolytic reactions resulting in uniform corrosion, galvanic corrosion, pitting corrosion, creep corrosion, dendrite growth, fretting, stress-corrosion cracking, and whisker growth. The article presents effective measures for minimizing the moisture retention in hermetic packages and/or moisture ingress in plastic packages. It concludes with information corrosion tests.

Discontinuously reinforced aluminum (DRA) alloy metal-matrix composites (MMCs) represent an advanced aluminum materials concept whereby ceramic particles, or whiskers, are added to aluminum-base alloys through the use of either ingot-melting or casting and/or powder-metallurgy (P/M) techniques. This article begins with a summary of general observations on the forging of discontinuously reinforced composites. It provides information on some of the specific experimental results obtained on various DRA systems, including 2xxx DRA alloys and cast DRA alloys. The article reviews the efforts on the modeling of behavior of specific alloy systems, with a comparison of experimental results to the modeling attempts. It concludes with information on the properties of deformation-processed DRA alloys.

This article focuses on the sample preparation methods for titanium honeycomb composites, boron fiber composites, and titanium/polymeric composite hybrids. These include mounting, sectioning, grinding, and polishing. The article also provides information on the sample preparation of unstaged and staged prepreg materials for optical analysis.

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.

Reinforcing fibers are a key component of polymer-matrix composites (PMCs), ceramic-matrix composites (CMCs), and metal-matrix composites (MMCs). This article discusses the mechanical and nonmechanical properties of these composites. It presents an overview of PMC, CMC, and MMC reinforcing fibers. The article describes cost-considered value-in-use of the ultimate-use temperature of selected fibers in three fiber categories: metal fibers or wires, oxide ceramic fibers, and non-oxide ceramic fibers.

This article discusses the types, oxide composition, as well as mechanical and physical properties of general-purpose and special-purpose glass fibers. It describes the glass melting and fiber forming processes and provides information on important commercial products such as continuous roving, woven roving, fiberglass mat, chopped strand, and textile yarns.

This article focuses on the production methods, properties, and applications of two main types of commercially available continuous-length ceramic fibers, namely, oxide fibers based on the alumina-silica system and on alpha-alumina, and nonoxide fibers based primarily on beta-phase silicon carbide. It provides a discussion on factors that are considered in understanding thermostructural capability of ceramic fiber for high-temperature ceramic-matrix composites (CMC) applications. The article tabulates other commercial oxide and nonoxide fiber types for CMC reinforcement.

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.

Molding compounds are plastic materials in varying stages of pellets or granulation that consist of resin, filler, pigments, reinforcement, plasticizers, and other ingredients ready for use in a molding operation. This article describes the material components and physical properties of sheet molding compounds (SMC). The three types of resin paste mixing techniques, such as batch, batch/continuous, and continuous, for an SMC operation are reviewed. The article discusses the design features and functional operations of the two types of SMC machines, namely, continuous-belt and beltless machines. It explains the formulation and processing of bulk molding compounds and reviews molding methods for bulk molding compounds, including compression, transfer, and injection molding. The effects of the fiber type and length and the matrix type on thermoset bulk molding compounds are discussed. It describes the four injection molding processes of injection molding compounds such as feeding, transporting, injecting, and flowing.

This article schematically illustrates a fiber placement system and provides information on the applications of fiber placement. It discusses materials and design considerations for fiber placement. The article provides information on techniques that can be used to eliminate areas of missing tows.