Macro/microscopic fracture characterizations of SiO2/epoxy nanocomposites

Macro/microscopic fracture characterizations of the SiO2/epoxy nanocomposite are studied experimentally. Both the load-displacement curve and the static fracture toughness are obtained using a three-point-bending test. Microscopic characterizations of fracture surface in nanocomposites are analyzed using the scanning electron microscope (SEM). Distribution of displacement field at the initial edge crack tip in nanocomposites is obtained by digital speckle correlation method. Crack propagation characterizations of nanocomposites are described using field emission scanning electron microscope (FE-SEM). The influence of nanoparticle contents on fracture behavior of nanometer composites is analyzed. The research results will be useful for structure design and fracture properties evaluation of nanocomposites. (C) 2007 Elsevier Masson SAS. All rights reserved.