Добірка наукової літератури з теми "Tailored Fibre Placement"

Polypropylene (PP)-cellulose fibre blends exhibit substantial potential for the production of high-performance textile fibre–reinforced composites. The production of reinforced parts from PP-cellulose composites through thermal shaping of intermingled fibre blends is a strategy to form parts which exhibit superior mechanical properties. In this study, the use of intermingled fibre slivers with different ratios of lyocell fibres (CLY) and PP fibres as raw materials for thermally formed composites was investigated. Such a concept will maximize the interface between the reinforcement fibres and polymer matrix. The cellulose fibres remain oriented along the direction in which the drawing process was performed, which forms the basis for tailored fibre placement in technical production. Because of good surface contact between the cellulose fibre surface and PP matrix, no special coupling agents were required to improve the interfacial adhesion between the two different polymers. The share of CLY and PP fibres in the composite varied from 50% w/w CLY content, up to 70% w/w CLY. Besides analysis of the mechanical properties, such as tensile strength and E-modulus, attention was directed towards moisture sorption of the composites. The rate of sorption and amount of water bound in the composite were found to be dependent on the cellulose fibre content. Composites with a higher CLY content exhibited a more rapid and higher moisture uptake. In water saturated state, the ultimate tensile strength of composites reduced from 160 MPa to 90 MPa, which is an indicator for a reduced adhesion between the CLY surface and PP matrix. The results indicate the potential of the intermingled fibre concept blend for the efficient manufacturing of composite parts.

Composites are materials formed by the combination of two or more components that acquire better properties than the ones obtained by each component on its own. Composites have been widely used in the industry due to its light weight and good mechanical properties. To improve these properties several layers of reinforced material (e.g., carbon fibre) are overlapped which produce an increase in the fibre consumption. In this sense Tailored Fibre Placement (TFP) embroidery can offer good opportunity to reduce the consumption of reinforced fibre while improving the mechanical properties due to the alignment of the fibres in the effort direction. This study analyzes the performance of carbon fibre reinforced composites with Polyester resin made with TFP embroidery technology against flexural strength efforts and without using plain woven fabrics to demonstrate that the use of reinforcement fabrics in composites can be optimized by a curved alignment of the fibers. Two different structures were embroidered with TFP technology, one simulating a woven fabric with straight unidirectional alignment of fibres in horizontal and vertical direction, and a second structure made with curvilinear alignment of carbon fibers. After the study of the flexural mechanical properties an improvement of 18% was obtained in maximum flexural strength.

When a composite laminate is tailored to suit its design intent, it is possible to improve the individual ply shapes to reduce component mass. If the laminate is going to be manufactured using an automated deposition system such as an automated fibre placement machine, then the design of the laminate will also influence the material deposition speed. This article identifies methodologies for indicating the likely impact on automated manufacture at the design optimisation stage by evaluating the ratio of ply perimeter to ply surface area when the laminate is defined as a simplified array of cells which are filled or unfilled to create a two-dimensional representation of the ply shape. A set of recommendations are made for using the methodology for improving deposition speed.