|
|
|
|
|
| Lan, Marine; Cartie, Denis; Davies, Peter; Baley, Christophe. |
| Automated fibre placement (AFP) enables the trajectory of unidirectional composite tape to be optimized, but laying down complex shapes with this technology can result in the introduction of defects. The aim of this experimental study is to investigate the influence of gaps and overlaps on the microstructure and tensile properties of carbon-epoxy laminates. First, a comparison between a hand-layup and AFP layup, draped and cured under the same conditions, shows equivalent microstructures and tensile properties. This provides the reference values for the study. Then, gap and overlap embedded defects (more or less severe) are introduced during manufacturing, on two cross-ply layups [(0°/(90°)5/0°] and [(90°/0°)2/90°]. Autoclave cure without a caul plate... |
| Tipo: Text |
Palavras-chave: Carbon fibre; Defects; Mechanical properties; Automated fibre placement (AR). |
| Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00275/38609/37138.pdf |
| |
|
|
| Baley, Christophe; Kervoelen, Antoine; Lan, Marine; Cartie, Denis; Le Duigou, Antoine; Bourmaud, Alain; Davies, Peter. |
| Automated fibre placement (AFP) has been used to manufacture flax/polypropylene biocomposites for the first time. This required preparation of tape with a calibrated width from impregnated fibre sheets. The unidirectional tapes showed polymer-rich zones on the surface. During manufacture the polypropylene (PP) is melted locally with a laser. A consolidation step in a hot press is then required to reduce void content. The flax fibres, composed of polysaccharides, have limited thermal resistance so optimization of the thermal cycle is necessary, but subsequent characterization of mechanical behaviour showed no evidence of property loss in spite of an additional melting cycle. AFP appears to be a promising manufacturing method for biocomposites. |
| Tipo: Text |
Palavras-chave: Structural composites; AFP; Biocomposites; Flax; PP. |
| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00307/41800/41009.pdf |
| |
|
|
| Lan, Marine; Cartie, Denis; Davies, Peter; Baley, Christophe. |
| This paper presents results from an experimental study of the influence of embedded defects created during automated fiber tape placement, on the mechanical properties of carbon/epoxy composites. Two stacking sequences have been examined, [(-45°/+45°)3/-45°] and [90°4/0°3/90°4], in which gaps and overlaps have been introduced during fiber placement. These materials have been cured in an autoclave either with or without a caul plate, then analyzed by ultrasonic C-scan. The microstructures were characterized by scanning electron microscopy. In-plane shear tests were performed on the ±45° laminates and showed that the use of a caul plate does not affect mechanical behavior of plies in the embedded defect region. Compression tests were performed on 0/90°... |
| Tipo: Text |
Palavras-chave: Structural composites; Defects; Mechanical properties; Mechanical testing. |
| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00302/41337/40523.pdf |
| |
|
|
|
