Fibre Prestressed Composites: Improvement of Flexural Properties through Fibre Prestressing

Abstract

The effects of fibre prestressing have been investigated on the flexural properties of glass-epoxy composites. Fibre prestressed composites were made by applying and maintaining a known amount of tension on the fibres during the curing process of the epoxy resin. In the next step, bending tests were conducted on a tensile machine using four point bending. In this study the modulus and strength of the fibre prestressed composite increased up to 33%. The experimental data also indicated that there existed a fibre prestressing level at which the flexural properties reached their maximum values. This prestressing level was found to be a function of the curing temperature. A mechanism has been proposed to explain the improvement of the flexural properties by the use of fibre prestressing during the cure process.

Keywords

prestress flexural modulus flexural strength epoxy glass fibre curing crack propagation composite

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