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The material characteristics of composites, their applications, and complex composites manufacturing processes depend on many factors. ...This essential information captures the state of the composites industry to assist engineering/technical professionals in charting a course for achieving economic success. ...., commercial/military aerospace, wind energy, automotive, and bicycle industries) address fundamental topics and explore the affordability of composites from raw material to end-of life-disposal costs with skilled perspectives that include: • Material characteristics and economics of composite structure • Complex manufacturing and specifics of assembly methods • Applications for composites • Product and human health • Safety and environmental impacts The authors provide strong basic economics concepts that are directly applied to the composites industry.

The following terminology has been generated by the ATA/IATA/SAE Commercial Aircraft Composite Repair Committee (CACRC) and provides terminology for design, fabrication, and repair of composite and bonded metal structures. ...The following terminology has been generated by the ATA/IATA/SAE Commercial Aircraft Composite Repair Committee (CACRC) and provides terminology for design, fabrication, and repair of composite and bonded metal structures.

As the aerospace industry continues on its quest for ever-increased efficiency, so goes the quest for ever-more composite content on aircraft. And with it, more opportunities to repair it. Typical composite panel fiber reinforcements are carbon, aramid, and fiberglass. ...The machining techniques for these typical composite materials are similar, but minor differences exist, such as the style of cutting tool or drill bit. ...Automated drilling methods that may be used during original manufacture are rarely used in typical composite repair situations.

This specification and its supplementary detail specifications cover carbon fibers in the form of continuous multifilament tow and yarn.

VGCF/carbon composites are unlike diamond in that, typical of most fiber reinforced composites, designed physical properties are incorporated into the composite through fiber architecture. ...VGCF/Carbon composites have been shown to demonstrate high thermal conductivity, comparable to that of CVD diamond, implying utility in high performance electronic packaging. ...VGCF/carbon composites are unlike diamond in that, typical of most fiber reinforced composites, designed physical properties are incorporated into the composite through fiber architecture. Thermal performance for die cooling is frequently determined by the thermal impedance of the package, measured from the junction to ambient, ϕja, or jucntion to case, ϕjc.

An example of the projected economic impact of weight savings possible through the use of composites for a commercial aircraft, and the elements and their current status of reinforced plastic composites research are presented. Projections of composite research in the next 3–5 years predict, in comparison to current aircraft aluminum alloys, an increase in specific strength by a factor of about 5, an increase in specific modulus by a factor of about 3, and a 300–500 F increase in thermal capability. ...The general history of the use of high-performance plastic reinforced composites is traced. An example of the projected economic impact of weight savings possible through the use of composites for a commercial aircraft, and the elements and their current status of reinforced plastic composites research are presented. ...An example of the projected economic impact of weight savings possible through the use of composites for a commercial aircraft, and the elements and their current status of reinforced plastic composites research are presented.

With the cost reductions anticipated in the next three or four years for graphite and boron filamentary composites, fiber composites hold considerable promise for general-aviation aircraft....As examples illustrating potential applications of filamentary composites, the cost/weight tradeoff ratios were calculated for three typical aircraft structural components: a landing-gear cantilever-spring strut, an I-beam, and a shear panel.

The approach is to build tooling from a polymer/graphite composite which will correlate with the thermal expansions of the composite being molded. Detailed information is shared on the development of master models, intermediary models and other sequential tooling steps. ...Assuming that large high temperature resistant composites will primarily be cured in autoclaves, an immediate requirement for suitable autoclave tooling exists. ...Finally, the paper shares the molding results with advanced thermoplastic composites.

The new 757/767 transports will be the first Boeing Commercial aircraft to commit advanced graphite composite material to initial production. Composite materials, mainly fiberglass in an epoxy matrix, have been used in Boeing military and commercial aircraft in ever increasing amounts for the past twenty (plus) years. ...The 757 and 767 are primarily made of aluminum, but do have significant amounts of composite material in their structure. Composite use on the 757/767 is a significant step toward that time when future transports will be primarily all-composite airplanes. ...Recently, the state-of-the-art of Advanced Composites (graphite and graphite/Kevlar hybrids in an epoxy matrix) progressed to the level that it could be committed to full-scale production.

Readers will gain a solid background about tribology, as well as a solid understanding of matrices, fibers and additives that make up engineered tribological composites. They will learn how manufacturing affects these composites, along with how friction and wear affect those materials. ...They will gain a better understanding of which materials provide the optimum balance of cost, friction and wear for various applications, enabling them to better create and apply engineered tribological composites for whatever application is at hand.

The increased use of composites in commercial aviation industry has created increased awareness of the effort required for development of certified structures. ...This is a result of the continuing use of advanced composites in commercially certified structures. While there is dispute over the extent of future advanced composite applications, it will be required on increasing amounts of commercial aviation structure. ...While there is dispute over the extent of future advanced composite applications, it will be required on increasing amounts of commercial aviation structure.

Research on metal-matrix composites for turbine compressors has demonstrated that four areas of compatibility are very important in composite design, and all must be considered in detail when specifying metal-matrix composites for structural applications. ...Research on metal-matrix composites for turbine compressors has demonstrated that four areas of compatibility are very important in composite design, and all must be considered in detail when specifying metal-matrix composites for structural applications. ...The designer must have detailed knowledge of every step in the composite manufacturing process to predict structural performance. Control of the manufacturing process to achieve maximum reinforcement from the filaments is considered the most important single factor.

A technique has been developed for producing high strength, low void reinforced polyimide composites. The state-of-the-art on high temperature reinforced plastics has been advanced considerably with this system, designated BPI-373. ...Areas investigated include development of a suitable prepreg, development of a composite fabrication process, and generation of design data on various systems. Reinforcements included in the study are E-glass and quartz fabrics, boron filaments, and graphite yarn.

Use of graphite/resin composites in engine nacelles has been restricted because the resin is flammable. Fiberglass/polyimide and graphite/polyimide laminates were treated with various phosphorylated polymers to obtain enhanced fire-resistance and high-char-yield products after exposure to a 2000°F flame for 15 minutes.

Optical microscopy is one of the most valuable, but under utilized, tools for analyzing fiber reinforced polymer matrix composites. This hands-on instructional book covers a wide range of topics including sample preparation, illumination and contrast techniques, methods and reagents, and applications. ...Studies are presented that provide insight into processing effects, toughening approaches, damage mechanisms, and environmental effects on the microstructure of composite materials. In addition, the power of optical microscopy to study the microstructure of these heterogeneous, anisotropic materials is illustrated with more than 180 full color images.

A new advanced composite based on poly-(amide-imide) matrix resin and graphite fiber has been developed. Polyamide-imide (PAI) resins are amorphous thermoplastics which have demonstrated good strength, toughness and thermal properties. ...PAI resin is expected to be a major matrix resin candidate in the aerospace industry's search for improved composites.

Dielectric composites are analyzed in terms of direct damage from shock waves, damage from longer duration slower pressures from vaporization of dielectric or metallic solids, direct magnetic forces and burning from long duration low current continuing components.

Gaps in composite structures are a risky factor in aeronautical assemblies. For mechanically joined composite components, the geometrical conformance of the part can be problematic due to undesired or unknown re-distribution of loads within a composite component, with these unknowns being potentially destructive. ...For mechanically joined composite components, the geometrical conformance of the part can be problematic due to undesired or unknown re-distribution of loads within a composite component, with these unknowns being potentially destructive. To prevent unnecessary preloading of a metallic structure, and the possibility of cracking and delamination in a composite structure, it is important to measure all gaps and then shim any gaps greater than 127 microns. ...To prevent unnecessary preloading of a metallic structure, and the possibility of cracking and delamination in a composite structure, it is important to measure all gaps and then shim any gaps greater than 127 microns.

A multi-axial dynamic test instrument was designed to perform wear testing of actual aircraft tires as well as tread/carcass composite specimens under laboratory loading conditions which simulate the elements of take-off, landing and taxiing operations. ...The wear tester consists of a self-spinning abrading head, mounted on the actuator of a servo-hydraulic test system, which faces either (1) the tread surface of a composite specimen clamped by a horizontal stretch frame or (2) the tread region of actual inflated tires. ...The test concept has been partially proven in the case of tread/carcass composite specimens by building a proto-type test apparatus and operating it successfully. In the current test set-up, the specimen is subjected to static tension to simulate a circumferential load in the tire footprint and the tread surface is in periodic contact with an abrading head under a specific level of pressure.

This document describes an inspection procedure for detecting, by use of a radiographic opaque tracer and fluoroscopy or radiography methods, flaws which have been produced as the result of cutting, machining, or drilling operations in composite or laminate structures.