Erratum to ‘Failure mechanisms of biological crossed-lamellar microstructures applied to synthetic high-performance fibre-reinforced composites’ [Journal of the Mechanics and Physics of Solids 125C (2019) 53–73]

Abstract The use of wood in high-performance composites based on laminated veneer products, plywood or wood hybrid elements thereof requires accurate prediction of strength of each individual ply. Previous research has shown that one dominating factor influencing the strength of birch veneers is the fibre orientation. The present study investigates the validity of the failure criteria after Tsai-Hill, Hoffmann and Kollmann for thin birch veneers under tensile loading. The fibre orientation in- and out-of-plane was measured by means of wide-angle X-ray scattering. Tensile strength and threshold values were determined in laboratory experiments. Pearson correlation between the predicted strength and actual strength ranged from 0.836 up to 0.883. Best correlation (r = 0.883) was achieved for Kollmann using a combined angle between in- and out-of-plane fibre orientation. It was shown that the failure criteria commonly used for manmade fibre reinforced composites are also applicable for thin birch veneers.

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The Optimisation of Flax Fibre Yarns for the Development of High-Performance Natural Fibre Composites

Advanced Composites Letters ◽

10.1177/096369350301200602 ◽

2003 ◽

Vol 12 (6) ◽

pp. 096369350301200 ◽

Cited By ~ 51

Author(s):

S. Goutianos ◽

T. Peijs

Keyword(s):

High Performance ◽

Fibre Composite ◽

Natural Fibre ◽

Reinforced Composites ◽

Flax Fibres ◽

Composite Systems ◽

Fibre Composites ◽

Structural Applications ◽

High Level ◽

Fibre Reinforced Composites

Currently most developments in the area of natural fibre reinforced composites have focused on random discontinuous fibre composite systems. The development of continuous fibre reinforced composites is, however, essential for manufacturing materials, which can be used in load-bearing/structural applications. The main problem in this case is the optimisation of the yarn to be used to manufacture the textile reinforcement. Low twisted yarns display a very low strength when tested dry in air and therefore they can not be used in processes such as pultrusion or textile manufacturing routes. On the other hand, by increasing the level of twist, a degradation of the mechanical properties is observed in impregnated yarns (e.g. unidirectional composites) similar to off-axis composites. Additionally, a high level of twist decreases the permeability of the yarns. This problem is addressed in the current work using yarns based on both long and short flax fibres.

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New process technology for high volume production of composites

Journal of Polymer Engineering ◽

10.1515/polyeng.2011.010 ◽

2011 ◽

Vol 31 (1) ◽

Cited By ~ 1

Author(s):

Walter Michaeli ◽

Jan Wessels ◽

Marco Pöhler ◽

Lionel Winkelmann

Keyword(s):

High Performance ◽

High Volume ◽

Fibre Volume ◽

Reinforced Composites ◽

Process Technology ◽

Compression Moulding ◽

New Process ◽

High Volume Production ◽

Volume Production ◽

Fibre Reinforced Composites

Abstract Despite their outstanding properties, the use of composites is still limited. The absence of an appropriate and economic high volume production technology is the most important restriction for the use of composites. This paper presents results of the research on new high volume production chains for continuous fibre reinforced composites which are based on the separation and parallelisation of the process steps “impregnation” and “forming and curing”. Two new impregnation processes for polyurethane and epoxy resin as well as a new compression moulding technology are introduced. The production of high performance parts with a fibre volume content higher than 50% in a cycle time below 10 min is described and analyses of the impregnation quality and the mechanical properties of the parts are presented.

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