Effects of fibre surface treatment on dynamic tensile properties of glass woven fabric reinforced vinylester composites

Glass fibre has been recognized as a strain rate dependent material. Its failure behaviour changes from brittle to ductile as the strain rate increases. As a consequence, the strength of the glass fibre increases, but the fibres within a composite become more prone to debond from the matrix because of the brittleness of the matrix material, promoted by the high strain rate. In the present study, the tensile responses of glass woven fabric reinforced vinyl ester composites with various fibre surface treatments are examined under static and dynamic loading conditions. The results show that both the ductility and the strength of the composites increased with increasing strain rate. The tensile strength was lower and the failure strain was higher in the weft direction than in the warp direction, because of excessive crimping in the former direction. The tensile strength in general increased with increasing silane concentration, for the majority of strain rates studied. The influence of fibre surface treatment on the impact tensile strength and modulus of composites were functionally similar, confirming the influence of fibre-matrix interphase properties on composite fracture behaviour at high strain rates.