iitm'atuzesutvcv Prepared by T. Feest, R.P. Harrison, A.R. Wheatley and M. Mulheron
AEROSPACE Light aircraft structural design in nonmetallics - - use of composite honeycomb for light aircraft Woodley, G.E. Aeronautical Journal Vol 85 No 847 (September 1981) pp 332-333 Although honeycomb/composite sandwich construction materials are used extensively in large commercial aircraft, their use in small, light aircraft is extremely small. This paper outlines the potential use of such materials for light aircraft structures such as wing panels, flaps and floor panels Model 206L composite vertkal fm Harse, J.H. 26th National S A M P E Symposium Proceedings (April 1981) pp 388401 A programme for the design and manufacture of a composite vertical fin for the Bell Helicopter 206L helicopter is described. A variety of materials was used; principally carbon, S-glass and Kevlar with epoxy. Some possibilities for composite light aircraft construction Webb, J.H. Aeronautical Journal Vol 85 No 847 (September 1981) pp 328-331 The results from several years' work at Cranfield Institute of Technology, on the use of glass-reinforced composites for light aircraft construction, are presented. In addition, details are given of one particular project, that of using a combination of composites with a simple metallic airframe. Sophisticated aircraft structure developments - - combat aeroplanes Sellars, R.J. and Terry, G. Aeronautical Journal Vol 85 No 847 (September 1981) pp 334-342 A brief description is given of some of the current work at the Warton Division of British Aerospace involving materials selection, technology demonstrators and future projects for the next generation of combat aircraft. Much of the work on materials is concerned with the use of carbon fibre composites, and details are given of the design considerations for metal/composite primary structures.
CARBON FIBRES Tensile properties of carbon fibres Zurek, W., Kocik, M., Calka, W. and Jakubczyk, J. Fibre Science and Technology Vol 15 No 3 (November 1981) pp 223-234 A method for eliminating errors in the determination of strain and actual breaking force for carbon fibres is presented. Tests carried out at 20°C to 200°C did not show any effects of temperature on the mechanical properties of the fibres. (Authors' abstract).
C O M P O S I T E S . A P R I L 1982
The thermal expansion of carbon-fibre reinforced plastics Part 6. The influence of fibre weave in fabric reinforcement Rogers, K.F., Kingston-Lee, D.M., Phillips, L.N., Yates, B., Chandra, M. and Parker, S.F.H. Journal o f Materials Science Vol 16 No 10 (October 1981) pp 2803-2818 The thermal expansion characteristics of a series of carbon fibre fabric-reinforced plastic laminates have been determined over the temperature range 90 K to 440 K. The results show that the ratio of fibre tow densities in the principal fibre direction, the crimp in the reinforcing fibres and the laminate stacking sequence all influence the magnitudes and temperature dependencies of the linear thermal expansion coefficients. Volume shrinkage effects resulting from temperature cycling are reported. Estimates of the linear thermal expansion coefficients of carbon fibres both parallel and perpendicular to the fibre axis are also given.
CEMENT MA TRICES Fatigue endurance of aged glass fibre reinforced cement West, J.M. and Walton, P.L. Journal o f Materials Science Vol 16 No 9 (September 1981) pp 2398-2400 The resistance of glass fibre-reinforced cement (ORe) stored in water for six years to flexural fatigue is reported. Tests were carried out at peak stresses between 6.0 and 18.2 MPa. An unreinforced mortar specimen was also studied and its fatigue endurance showed greater scatter than the GRC samples. It is concluded that fatigue is unlikely to impose a significant limitation on the current usage of GRC. Mechanical properties of a low density aluminous cement/perUte composite Meiser, M.D. and Tressler, R.E. American Ceramic Society Bulletin Vol 60 No 9 (September 1981) pp 901-905 The effects of altering microstructural parameters on the properties of low density aluminous cement-bonded perlite composites are investigated. Changes in mechanical properties arc found to be dominated by variation in the bulk density rather than by the cement-to-perlite ratio or perlite properties. Increasing the test temperature produces a reduction in composite strength to a minimum value at 400°C as the organic binder pyrolyzes. A further increase in temperature results in increased composite strength as the cement developed ceramic bonds between the perlite particles. Properties of high-alumina cement reinforced with alkali-resistant glass fibres Majumdar, A.J., Singh, B. and Ali, M.A. Journal o f Materials Science Vol 16 No 9 (September 1981) pp 2597-2607 The changes in mechanical properties of cement composites made from high-alumina
cement and Cem-FIL AR-glass fibres kept in three different environments up to ten years are described. Reductions in composite strength are reported for those samples stored in wet conditions, though the values obtained were significantly better than the corresponding results with Portland cement composites reinforced with E-glass fibres. The reductions of strength are attributed to chemical corrosion of the glass fibre and conversion of the matrix.
GENERAL Analysis of composite laminates and fibre composite repair schemes Jones, R. and Callinon, R.J. Fibre Science and Technology Vol 15 No 3 (November 1981) pp 199-207 The development and use of finite element methods for analyzing laminated composites and structures repaired with a bonded overlay of fibre-reinforced composite material. Application of UV resonance Raman spectroscopy to the detection of sHane coupling agent on glass surfaces Ishaida, H., Koenig, J.L., Asumoto, B. and Kenney, M.E. Polymer Composites Vol 2 No 2 (April 1981) pp 75-80 Uv resonance Raman spectroscopy was used to study the silane P C S i ( O H ) (OSi(CHa)2(CH = CH2), which has potential as a coupling agent for glass fibre composites. Crystalline samples of the silane without glass and films on E-glass fibres and high surface area silica at levels less than a monolayer were investigated. An approach for plane stress analysis of rectilinearly reinforced composites Sinha, P.K. and Prasad, V.S. Fibre Science and Technology Vol 15 No 3 (November 1981) pp 209-221 A general approach for determining the plane stress in rectilinearly orthotropic composites is presented. The method is based on known values of boundary stresses, at preselected points, which arc used to determine stresses in the bulk material. The compression strength of composites with kinked, misaligned and poorly adhering fibres Martinez, G.M., Piggott, M.R., Bainbridge, D.M.R. and Harris, B. Journal o f Materials Science Vol 16 No 10 (October 1981) pp 2831-2836 The compressive strength of aligned fibre composites, at moderate fibre volume fractions, is shown to depend linearly on volume fraction. A fall-off in strength at Vf = 0.4 is reported for composites containing Kevlar and high strength carbon fibres. Poor fibre matrix adhesion resulted in a loss of composite strength, as did kinking in the fibres when the fibre radius of curvature was reduced below 5 mm. Fibre misalignment
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