Solid Particle Erosion of Knitted Glass Fabric-Reinforced Poly(Ethylene Terephthalate) Composites

The erosion behaviour of knitted fabric-reinforced glass fibre (GF)/poly(ethylene terephthalate) (PET)-composites was investigated by solid particle impact with irregularly shaped corundum particles. Angular (30° to 90°) and morphological (matrix crystallinity) dependencies of the wear rate were studied. The specific erosion wear rate was recorded and scanning electron microscopy (SEM) investigations have been performed to describe the wear mechanisms. In general, high erosive wear rates were detected. A maximum erosion rate was found at impacting angles of 60° for all investigated composites. At normal impact (90°) lower wear rates were observed which depended also on the matrix crystallinity. The erosion wear rate increased with increasing crystallinity, knit stretching and annealing (crystallinity change by cold crystallisation). No influence was found for the erosion direction when tests were performed in wale (WD) and course (CD) direction of the knit, respectively. SEM micrographs supported the semi-brittle wear behaviour showing brittle fracture of the glass fibres and the ductile deformation of the PET matrix.