|
|
|
|
|
| Perrot, Yves; Baley, C; Grohens, Y; Davies, Peter. |
| Composites based on glass fiber reinforced low styrene emission polyester resins have been widely used over the last 10 years, in order to meet increasingly strict safety regulations, particularly in the pleasure boat industry. Previous studies of their mechanical properties suggested that although these resins are generally more brittle than traditional orthophthalic polyester resins this did not adversely affect the properties commonly used for quality control (short beam shear and tensile failure strength of mat reinforced composites). In the present paper results from a more detailed study of damage behaviour are presented. Tests include fracture toughness (K (Ic) ) tests on resins, fibre/matrix interface energy, detection of composite damage... |
| Tipo: Text |
Palavras-chave: Interface properties; Damage initiation; Styrene emission; Unsaturated polyester; Glass fibers. |
| Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-2316.pdf |
| |
|
|
| Baral, N; Davies, Peter; Baley, C; Bigourdan, Benoit. |
| This paper presents a study of the delamination resistance Of unidirectional carbon fibre reinforced epoxy composites manufactured from prepreg for racing yacht mast applications. Fibre modulus has been varied from 290 to 640 GPa. Two manufacturing methods, oven cure under vacuum and autoclave, were used to produce samples. Results show that delamination resistance tinder mode I and mixed mode loading decreases as fibre modulus increases. The manufacturing route affects G, values by modifying interlaminar layer geometry but does not change the trend of lower toughness with increasing fibre modulus. For the pitch composites crack propagation is observed within the fibres, in addition to more usual matrix and interface cracking. For the very high modulus... |
| Tipo: Text |
Palavras-chave: Mixed mode; Fracture toughness; Polymers; Carbon fibres; Delamination. |
| Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-3772.pdf |
| |
|
|
| Baley, C; Cailler, M. |
| The experimental sailing boat "Mesure Z," has been designed and built on behalf of F.I.N., (the French marine industry association). This research project has been managed in close collaboration with Bureau Veritas, Ifremer and the CEA. The GRP hull is similar to that of a production sailing boat, but it has been designed as a transducer-hull, i.e. a hull sufficiently sensitive to allow measurements (hull strains, acceleration, spar loads, etc), due to its structure and mechanical characteristics. This paper presents different aspects of the experimental boat, the materials and structure of the transducer-hull, and the behaviour of the central and bow regions of the hull during sailing. |
| Tipo: Text |
Palavras-chave: Finite element method; Navigation; Measurement; Boating; Sailing ships; Mechanical properties; Ship technology; Composite materials; Navigation; Comportement mécanique; Eléments finis; Mesure; Matériau composite; Voilier. |
| Ano: 1992 |
URL: http://archimer.ifremer.fr/doc/1992/acte-1073.pdf |
| |
|
|
| Baral, N; Guezenoc, H; Davies, Peter; Baley, C. |
| This paper presents test results from mode I interlaminar fracture and transverse tensile tests on unidirectional carbon/epoxy composites used in racing yacht construction. Fibre modulus has been varied from 380 to 640 GPa. PAN fibre reinforced composite properties, delamination resistance (G(Ie) and G(Ip)) and transverse strain to failure, decrease as fibre modulus increases. Composites based on the highest modulus pitch fibres show higher transverse failure strains than the highest modulus PAN fibre composites. A distinct failure mechanism, crack propagation within the fibres, was observed for the pitch based reinforcement. The transverse tensile tests allowed transverse fibre modulus to be estimated as 11.5 GPa for the PAN and 9 GPa for the pitch... |
| Tipo: Text |
Palavras-chave: Carbon fibre; Fracture; Deformation; Delamination; Composite materials. |
| Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-3723.pdf |
| |
|
|
| Davies, Peter; Baley, C; Loaec, Henri; Grohens, Y. |
| This paper presents results from a study of the influence of surface preparation on the mechanical performance of overlaminated polyester composites. Panels of 16 woven glass plies have been prepared in two halves by hand lay-up. After the first 8 plies were laminated the surface was either protected by a peel ply or left in air. The overlamination of the second half of the composite thickness was completed after different periods and interlaminar shear, flexure and mode I fracture specimens were tested. The results enabled the influence of the delay and the surface condition to be related to mechanical performance. Surfaces protected with peel plies show very low G(Ic) propagation energy release rates. Results are compared to those from continuous... |
| Tipo: Text |
Palavras-chave: Mode I; Woven; Peel ply; Glass/polyester; Overlamination; Interlaminar. |
| Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/publication-1034.pdf |
| |
|
|
| Perrot, Y; Davies, Peter; Kerboul, Andre; Baley, C. |
| Delays between lamination of structures and secondary bonding are common in boatbuilding. This paper presents results from an experimental study of the influence of manufacturing procedure on the bond strength of unidirectional glass fibre reinforced polyester composites. Continuously laminated panels are taken as the reference and compared with panels overlaminated after delays of one week with and without peel ply protection. A standard polyester and low styrene DCPD formulation were tested. ILSS testing is shown not to be sensitive to the procedure but crack propagation tests show very large differences in mode I fracture energy. A small drop in fracture energy is measured for a delay of one week between lamination of the first and second halves of the... |
| Tipo: Text |
Palavras-chave: Mode I; ILSS; Peel ply; Lamination procedure; Low styrene content resins; Glass/polyester composites. |
| Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-4557.pdf |
| |
|
|
| Davies, Peter; Morvan, C; Sire, O; Baley, C. |
| This paper presents results from a study of fibres extracted from Zostera marina eel-grass collected from the Baltic coast. This species of sea-grass is shown to contain small diameter (around 5 mu m) fibres composed of similar to 57% cellulose, similar to 38% of non-cellulosic polysaccharides (mainly xylan) and similar to 5% of residual matter so-called Klason lignin. This composition is quite different to that of commonly used terrestrial fibres. Single fibre stiffness values up to 28 GPa were measured. This stiffness combined with a low density could provide an attractive reinforcement for composite materials, and may be particularly suitable for use in bio-degradable structures. |
| Tipo: Text |
Palavras-chave: Xylan; Tension; Mechanical behaviour; IR spectroscopy; Sea grass; Fibre. |
| Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-2607.pdf |
| |
|
|
| Maurin, R; Davies, Peter; Baral, N; Baley, C. |
| In this study the transverse modulus of three high modulus (M40, M46 and K63712) carbon fibres has first been measured directly by nano-indentation measurements. Transverse tensile tests on unidirectional epoxy composites were then performed, and the comparison was made between transverse fibre properties from indentation and those needed to obtain the measured transverse composite modulus using micromechanics expressions. The latter tended to underestimate values from indentation, by up to 36%, and reasons for this are discussed. Values of transverse fibre modulus determined by both methods decrease as longitudinal fibre modulus increases. |
| Tipo: Text |
Palavras-chave: Transverse tensile; Nano indentation; Epoxy; Carbon fibre. |
| Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-4502.pdf |
| |
|
|
| Baley, C; Perrot, Yves; Busnel, F; Guezenoc, H; Davies, Peter. |
| Flax provides a renewable source of fibres with good mechanical properties, which justifies its use as a reinforcement for polymers. Composite materials made with flax which has only undergone mechanical treatments (stripping followed by combing) results in the presence of bundles of fibres. When a unidirectional flax/polyester ply is loaded in transverse tension the damage mechanisms are complex; cracks develop in the matrix, and at the fibre/matrix interface, but they also appear within the fibres themselves and in the lamellae within the fibre bundles. This emphasises the highly anisotropic nature of these flax fibres, whose average longitudinal Young's modulus is 59 GPa and whose transverse modulus is estimated here to be 8 GPa. (c) 2006 Elsevier B.V.... |
| Tipo: Text |
Palavras-chave: Unidirectional; Transverse tensile; Polyester; Glass; Flax; Composite materials. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-6362.pdf |
| |
|
|
|
