Ultra-strong and stiff randomly-oriented discontinuous composites: closing the gap to quasi-isotropic continuous-fibre laminates
Journal article, 2020

Conventional randomly-oriented Tow Based Discontinuous Composites (TBDCs) are materials which combine good mechanical properties, lightweight and high manufacturability, and are therefore interesting for high-volume transport industries. This paper proposes, designs and successfully demonstrates a pathway to produce TBDCs with outstanding stiffness and tensile strength, by using ultra-thin tapes of (ultra-) high modulus carbonfibres. Numerical models are used to explore the design space of discontinuous composite materials, in order to identify the optimal microstructural design to maximise stiffness and strength. Selected microstructures are manufactured and tested under tension; the experimental results show good agreement with the numerical predictions, and demonstrate a significant increase in the tensile strength and Young's modulus of TBDCs by reducing the tow thickness and increasing the modulus of the fibres. Strength and stiffness increases of over 100% compared with the commercially available TBDC systems are achieved, resulting in mechanical properties that match the strength and overcome the stiffness of aerospace-graded continuous-fibre laminates.

Analytical modelling

A. Discontinuous reinforcement

Stress transfer

Mechanical testing

Author

Marco Alves

Imperial College London

David Carlstedt

Chalmers, Industrial and Materials Science, Material and Computational Mechanics

Fredrik Ohlsson

Oxeon AB

Leif Asp

Chalmers, Industrial and Materials Science, Material and Computational Mechanics

Soraia Pimenta

Imperial College London

Composites Part A: Applied Science and Manufacturing

1359-835X (ISSN)

Vol. 132 105826

Ultra-stiff and strong composites for structures with complex geometries

VINNOVA, 2018-10-01 -- 2019-06-30.

Areas of Advance

Transport

Materials Science

Subject Categories

Vehicle Engineering

Composite Science and Engineering

DOI

10.1016/j.compositesa.2020.105826

More information

Latest update

1/7/2021 1