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A Study on the Initial Fracture Behavior of Roving Glass Woven Fabric Reinforced Composites

Woven fabrics, characterized with the special structure form, are widely used as reinforcement of textile composites in structural applications by far. Roving cloth, as one of the woven fabrics, is characterized with the cross section of the warp fiber bundles and weft fiber bundles, which are usually used as reinforcement for laminate molding. GFRP (glass fiber reinforced plastic) materials, characterized by high strength, low cost, low density, corrosion resistance, are also adopted in the form of glass woven fabric as reinforcements.

Generally, final fracture of composites is considered to be caused by the accumulation of these microcracks or fractures. Thus, initial fracture, which represents the initiation of micro fracture, is considered to be significant in determining the fracture mechanism.

In this paper, investigation on the initial fracture behavior was carried out on roving glass woven fabric reinforced composites which were manufactured by hand lay-up method. Two kinds of roving glass woven fabrics of different FAW (Fabric Area Weight) and crimp ratio, Type A of 570 g/m2 and Type B of 800 g/m2, were adopted as reinforcement. Tensile test was conducted and tensile properties were discussed on specimens of 6 degrees 0°/5°/10°/80°/85°/90°. The initial fracture behavior was observed on 0 degree and 90 degree and the fracture mechanism was compared and discussed among 5°/10°/80°/85°.

The results showed that Type B had higher tensile modulus and tensile strength than that of Type A. And different initial fracture behaviors between two kinds of materials was observed and analyzed, which indicated that the crimp ratio played an important role of woven fabric reinforced composites in fracture mechanism. After the tensile test, models of the woven fabric were built according to the geometric dimension of the fabric for 0 degree and 90 degree, then the initial fracture and interfacial strength was simulated by the software Marc. By combining the experimental results and finite element analysis, initial behavior of fracture progress in roving glass woven fabric reinforced composite materials was discussed and predicted.

In future work, 3D models in multiscale are supposed to be built and further simulation of two different crack modes are also planned to be carried out.


Article by Zhilan Xu and Atsushi Yokoyama, from Kyoto Institute of Technology, Kyoto, Japan.

Full access: http://mrw.so/4G9ByY

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