Effect of 60Co gamma-irradiation on interface and abrasive wear of glass-reinforced polyester composite

The fibre-matrix interface in polymer composites is characterized by van der Waals'-like forces, which act between covalently bonded organic polymer and high-strength inorganic glass fibres (physisorption) and chemical bonding between the fibre and polymer, involving reactive groups (chemisorption). These mechanisms at the interface are responsible for the lowering of frictional forces and minimizing wear rate. Crosslinking polymer-like unsaturated polyesters provide sharp interfaces due to their low boundability. Chemical bonding increases the mechanical strength of the interface. In the present study we investigated the effect of gamma-irradiation on the fibre-matrix interface by determining the abrasive wear of the polymer composite. The wear rate of gamma-irradiated glass fibre-reinforced composite has been compared with that of the unirradiated composite. It can be concluded that the abrasive wear of the composite was reduced considerably when exposed to high-energy gamma-irradiation from a Co source. The reasons for this change can be the resin hardening and improved fibre-matrix interfacial bonding due to gamma-irradiation. (5 figures, 10 references). (author)