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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.

Barriers to the more extensive use of advanced composites in heavily loaded structure on commercial transports are discussed from a materials viewpoint. ...Relationships between neat resin modulus, resin fracture energy, interlaminar fracture energy, composite compression strength, and post-impact compression strength will be shown. Powder and slurry processing techniques will be discussed.

In fabrication of aircraft parts using composites, it is necessary to be able to assess the quality of material simply and quickly, both for design purposes and as a means of ensuring satisfactory manufacturing techniques. ...The use of density for the determination of fiber volume of composite parts was developed in order to reduce the time and cost of quality assurance while still maintaining reliability.

For the ultimate in high temperature capability, refractory metals, ceramics, ceramic matrix composites (CMCs), and carbon/carbon (C/C)composites each provide particularly beneficial attributes, but with selected limitations.

Abstract Fiber-reinforced composites are widely used in injection molding processes because of their high strength and high elastic modulus.

An aircraft tire durability study is underway to investigate the deformation and fracture behavior of cord-rubber composites. This study will identify the important parameters responsible for the structural failure of aircraft tires by the use of analytical and laboratory prediction methods. ...These methods will also identify the interaction between material property degradation and damage accumulation in cord-rubber composites. Preliminary results using coupon specimens of tire carcass have revealed that prolonged static and cyclic loading sequences produce extensive interply shear deformation at the free edges resulting in cord-matrix debonding followed by delamination type failure. ...It was also determined experimentally that a fatigue endurance limit can be established for cord-rubber composites. Analytical methods using finite element models of coupon specimens have demonstrated reasonable accuracy in predicting load-displacement response and interply shear strain variations.

Metal matrix composites (MMCs) exhibit superior characteristics such as low weight, high stiffness, and high mechanical and physical properties. ...In this study, dry turning experiments were conducted for two different inserts and coated carbide on a bar of titanium metal matrix composite (Ti-MMC). Semi-finishing machining is operated with cutting parameters based on the tool supplier's recommendations which were not fully optimized.

One of the recent technological breakthroughs that has enhanced the Delta's service capabilities is the development and use of large composite structures in critical components. Among these structures is the payload fairing, which acts as a protective shroud for the spacecraft. ...Traditional composite manufacturing techniques, however, are very labor-intensive and time-consuming. The challenge to produce composite hardware at a competitive cost and reasonable manufacturing cycle time was met through the application of advanced Computer-Aided Design/Computer-Aided Manufacturing (CAD/CAM) techniques, including automated material cutting and laser projection. ...The challenge to produce composite hardware at a competitive cost and reasonable manufacturing cycle time was met through the application of advanced Computer-Aided Design/Computer-Aided Manufacturing (CAD/CAM) techniques, including automated material cutting and laser projection.

Since deregulation, the passenger and cargo market have taken on a new prospective in the air transportation industry. Todays demanding cargo market require: Shorter on ground turn around time Reduced conversion time for convertible aircraft Increased reliability Low Maintenance Reduced labor costs New aircraft development will also give strong consideration to the factors listed above since the cost of ownership plays a very significant role in the purchase of new airplanes.

This Aerospace Standard (AS) establishes the requirements for suppliers of Composites to be accredited by Nadcap. Nadcap accreditation is granted in accordance with SAE AS7003 after demonstration of compliance with the requirements herein. ...The requirements may be supplemented by additional requirements specified by the Nadcap Composites Task Group. Using the corresponding Audit Criteria (PRI AC7118) will ensure that accredited Composites suppliers meet all of the requirements in this standard and all applicable supplementary standards and applicable AS7118 slash sheets. ...Using the corresponding Audit Criteria (PRI AC7118) will ensure that accredited Composites suppliers meet all of the requirements in this standard and all applicable supplementary standards and applicable AS7118 slash sheets.

Machine tools meet new materials If you're in the business of making machine tools for aerospace applications, you're probably working on improvements in cutting tough metals and composites.

CMH-17 provides information and guidance necessary to design and fabricate end items from composite materials. It includes properties of composite materials that meet specific data requirements as well as guidelines for design, analysis, material selection, manufacturing, quality control, and repair. ...H") of the second volume of the CMH-17 compendium contains statistically-based data for polymer matrix composites that meets specific CMH-17 population sampling and data documentation requirements, covering material systems of general interest. ...Seventeen new data sets with complete documentation and publicly available specifications were added in the new Revision H of the Composites Materials Handbook, Vol.2. The new data sets include carbon fiber and glass fiber composites.

Boron-epoxy composites are presently being utilized for primary aircraft structures. The basic joining technique for these materials of construction is adhesive bonding. ...This presentation briefly reviews the mechanical properties of adhesive-bonded composites, the techniques for manufacture, and the quality assurance necessary for acceptance of such structures.

The selected guidance on technical topics related to this class of composites includes material selection, processing, characterization, testing, data reduction, design, analysis, quality control, application, case histories, and lessons learned of typical ceramic matrix composite materials. Volume 5, which covers ceramic matrix composites, supersedes MIL-HDBK-17-5 of June 17, 2002. ...CMH-17 provides information and guidance necessary to design and fabricate end items from composite materials. It includes properties of composite materials that meet specific data requirements as well as guidelines for design, analysis, material selection, manufacturing, quality control, and repair. ...The fifth volume of this six-volume compendium publishes technical guidance and properties on ceramic matrix composite material systems. The selected guidance on technical topics related to this class of composites includes material selection, processing, characterization, testing, data reduction, design, analysis, quality control, application, case histories, and lessons learned of typical ceramic matrix composite materials.

Composite Propeller Blades have been developed and are now in production for the new generation of turbo-prop commuter aircraft. ...The method of manufacture utilises special tooling and a resin injection process specifically developed to produce composites with good fibre volume fractions and correspondingly high structural properties. Quality Control and NDT methods have been developed to ensure a high quality product, which involves the use of Ultrasonic, Radiographic and Vibrational Analysis. ...Certification of the Composite Propeller has necessitated rigorous structural and environmental testing of the finished blades, involving specialised rigs and techniques.

Another aspect of the ceramic composites are their non-isotropic mechanical and thermal characteristics. Models for both the erosion and the heat transport properties have been established.

Composites are finding more and more applications in the aircraft industry. Drilling good quality holes is a major challenge for the manufacturing industry.

Laminated metal-metal composites can have attractive fracture toughness properties; they also offer potentially good fatigue performance. ...Eight-layer composites were compared with solid sheets of nearly the same total metal thickness. Both fracture toughness and fatigue properties were determined.

PEEK™ polymer, successfully displaces metals, traditional composites, and other plastics in a growing number of aerospace applications due to its exceptional properties and ability to be easily fabricated into high tolerance parts through multiple manufacturing techniques.

Additive Manufacturing of Aerospace Composite Structures: Fabrication and Reliability introduces the reader to the current state of technologies involved in processing and design of polymer-reinforced fiber composites using additive manufacturing's automated fiber placement methods, through ten seminal SAE International papers. ...Additive Manufacturing of Aerospace Composite Structures: Fabrication and Reliability introduces the reader to the current state of technologies involved in processing and design of polymer-reinforced fiber composites using additive manufacturing's automated fiber placement methods, through ten seminal SAE International papers. ...Additive Manufacturing of Aerospace Composite Structures: Fabrication and Reliability approaches the question of quality in these structures from a hands-on, solution-driven perspective.