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Tribology of the carbon‐fibre‐reinforced plastics has been investigated. The wear‐resistance of carbon‐fibre‐reinforced plastics was found to be much better than those of other plastics reinforced with fibres of glass and stainless steel and was affected by the fibre‐orientation relative to sliding. Law of mixture in the frictional coefficient of composite materials was deduced; a comparison of calculated values with experimental data showed good agreements. Wear‐resistance of the carbon‐fibre‐reinforced plastics against fretting was also examined; good wear‐resistance was obtained when sliding within a region about 30° from the carbon‐fibre axis.

A review of CFRP dealing with its processing, properties and some of the ways in which it could be used in conjunction with conventional materials. The importance of the utilization of carbon fibres in commercially useful as well as experimental structures is discussed. This may be achieved by using the fibres in conjunction with conventional sheet metal components, as a preliminary step toward the 100 per cent reinforced plastic structure. A few such applications are described, together with a brief summary of the fibre processing and properties as an aid to preliminary design studies.

To make full use of the tensile strength of near surface mounting (NSM) pasted carbon fiber reinforced plastics (CFRP) strips and further increase the flexural bearing capacity and flexibility of reinforced concrete (RC) beams, a new composite reinforcement method using ultra-high performance concrete (UHPC) layer in the compression zone of RC beams is submitted based on embedding CFRP strips in the tension zone of RC beams. This paper aims to discuss the aforementioned points.

The experimental beam was simulated by ABAQUS, and compared with the experimental results, the validity of the finite element model was verified. On this basis, the reinforced RC beam is used as the control beam, and parameters such as the CFRP strip number, UHPC layer thickness, steel bar ratio and concrete strength are studied through the verified model. In addition, the numerical calculation results of yield strength, ultimate strength, failure deflection and flexibility are also given.

The flexural bearing capacity of RC beams supported by the new method is 132.3% higher than that of unreinforced beams, and 7.8% higher than that of RC beams supported only with CFRP strips. The deflection flexibility coefficient of the new reinforced RC beam is 8.06, which is higher than that of the unreinforced beam and the reinforced concrete beam with only CFRP strips embedded in the tension zone.

In this paper, a new reinforcement method is submitted, and the effects of various parameters on the ultimate bearing capacity and flexibility of reinforced RC beams are analyzed by the finite element numerical simulation. Finally, the effectiveness of the new method is verified by the analytical formula.

THIS article considers the role of carbon fibre reinforced plastic as a reinforcement for conventional aircraft structural components. It is in this mode that we expect to see the most extensive use of this new material in the near future, particularly for applications in commercial airliners where, more than in most fields of engineering, it is necessary to temper the vital pressure for greater efficiency by an appreciation of the problems in attempting to achieve too much too soon. The conclusions are based on research and development by British Aircraft Corporation, Weybridge Division, during the past year, primarily in its intensive design development of the new wide‐bodied B.A.C. Three‐Eleven airliner.

Details the development of composites, in particular carbon fibre reinforced plastics, for use in aerospace structures. Describes a wide range of products manufactured by various companies. Looks at the integrity of these materials and the testing methods used to ensure this. In particular, discusses metal matrix composites, aluminium/silicon carbide particulate MMCs and fibre‐metal laminates. Finally looks at advanced composites’ promise of being able to meet the needs of high specific properties and enhanced temperature capability required for future engines.

The purpose of this study is for solving many issues in production that includes processing of complex-shaped profile, machining of high-strength materials, good surface finish with high-level precision and minimization of waste. Among the various advanced machining processes, abrasive jet machining (AJM) is one of the non-traditional machining techniques used for various applications such as polishing, deburring and hole making. Hence, an overview of the investigations done on carbon fiber-reinforced polymer (CFRP) and glass fiber-reinforced polymer (GRFP) composites becomes important.

Discussion on various approaches to AJM, the effect of process parameters on the glass fiber and carbon fiber polymeric composites are presented. Kerf characteristics, surface roughness and various nozzle design were also discussed.

It was observed that abrasive jet pressure, stand-off distance, traverse rate, abrasive size, nozzle diameter, angle of attack are the significant process parameters which affect the machining time, material removal rate, top kerf, bottom kerf and kerf angle. When the particle size is maximum, the increased kinetic energy of the particle improves the penetration depth on the CFRP surface. As the abrasive jet pressure is increased, the cutting process is enabled without severe jet deflection which in turn minimizes the waviness pattern, resulting in a decrease of the surface roughness.

The review is limited to glass fiber and carbon fiber polymeric composites.

In many applications, the use of composite has gained wide acceptance. Hence, machining of the composite need for the study also has gained wide acceptance.

The usage of composites reduces the usage of very costly materials of high density. The cost of the material also comes down.

This paper is a comprehensive review of machining composite with abrasive jet. The paper covers in detail about machining of only GFRP and CFRP composites with various nozzle designs, unlike many studies which has focused widely on general AJM of various materials.

AFTER BRIEFLY considering the surface areas of aircraft for which lightning strikes are a major factor in the selection of constructional materials, a review is made of published information concerning the effects of lightning on these various materials. The materials are considered under three headings: metallic, non‐conducting (e.g. glass‐fibre‐reinforced‐plastics) and semi‐conducting (e.g. carbon‐fibre‐reinforced plastics). Simulated lightning current tests are the main source of information and the review is primarily concerned with the results of such tests. To aid assessment of the relevance of the test currents that have been used, an outline of the current characteristics of lightning discharges is also given.

Growing demands on the part of the aircraft industry, particularly in the field of light‐aircraft construction, have led in recent years to the increased use of carbon fibre‐reinforced plastics. This material, better known by its abbreviation CFRP, is characterised by extremely high resistance to fracture, high stiffness and almost ideal density. A visit to the market leader in lightweight low‐cost gliders, the aircraft manufacturing company of Grob, confirms that everything is easier with CFRP. In fact, thanks to CFRP, the Swabian aircraft weigh less than comparable models without carbon fibres — and at the same time are much more resistant to fracture.

The aerospace, energy and automotive industries have seen wide use of composite materials because of their excellent mechanical properties, along with the benefit of weight reduction savings. As such, the purpose of this study is to provide an understanding of the mechanical performance of these materials under extreme operational conditions characteristic of in-service environments.

This study is novel in that it has evaluated the tensile performance and fracture response of additively manufactured continuous carbon fiber embedded in an onyx matrix (i.e. nylon with chopped carbon fiber) at cryogenic and room temperatures, for specimens manufactured with an angle between the specimen lying plane and the working build plane of 0°, 45° and 90°.

Research findings reveal enhanced tensile properties (i.e. ultimate tensile strength and modulus of elasticity) by the 0° (X) built specimens, as compared with the 45° (XZ45) and 90° (Z) built specimens at cryogenic temperature. A reduction in ductility is observed at cryogenic temperature for all build orientations. Fractographic analysis reveals the presence of fiber pullout/elongation, pores within the onyx matrix and chopped carbon fiber near fracture zone of the onyx matrix.

Research findings present tensile properties (i.e. ultimate tensile strength, modulus of elasticity and elongation%) for three-dimensional (3D)-printed onyx with and without reinforcing continuous carbon fiber composites at cryogenic and room temperatures. Reinforcement of continuous carbon fibers and reduction to cryogenic temperatures appears to result, in general, in an increase in the tensile strength and modulus of elasticity, with a reduction in elongation% as compared with the onyx matrix tensile performance reported at room temperature. Fracture analysis reveals continuous carbon fiber pull out for onyx–carbon fiber samples tested at room temperature and cryogenic temperatures, suggesting weak onyx matrix–continuous carbon fiber adhesion.

To the best of the authors’ knowledge, this study is the first study to report on the cryogenic tensile properties and fracture response exhibited by 3D-printed onyx–continuous carbon fiber composites. Evaluating the viability of common commercial 3D printing techniques in producing composite parts to withstand cryogenic temperatures is of critical import, for aerospace applications.

The purpose of this paper is to investigate the buckling behavior of the load-carrying support structure of a wind turbine blade.

Experimental experience has shown that local buckling is a major failure mode that dominantly influences the total collapse of the blade.

The results from parametric analyses offer a clear perspective about the buckling capacity but also about the post-buckling behavior and strength of the models.

This makes possible to compare the response of the different fiber-reinforced polymers used in the computational model.

Furthermore, this investigation leads to useful conclusions for the material design optimization of the load-carrying box girder, as significant advantages derive not only from the combination of different fiber-reinforced polymers in hybrid material structures, but also from Kevlar-fiber blades.