Effect of Filler Size and Matrix Properties on Fracture Toughness of Particulate Composites

An experimental study was conducted to investigate the effect of filler size and matrix ductility on fracture toughness of particulate composites. For this purpose, two sand/polyester composite systems were studied. In the first system, three types of polyester with different ductility were used with a constant sand particle size. In the second system, the matrix was the same but sand particle size was changed. Fracture toughness tests were conducted using single-edge notch beam specimen. The fracture toughness of the tested particulate composites was not directly related to the filler size, however it was directly influenced by matrix ductility. Fractographic analysis of fracture surfaces confirmed that crack pinning mechanism is an active fracture process in par ticulate composites.