Unidirectional laminates of reinforced glass/epoxy composites UE400/ET443 were tested by the use of fracture mechanics tests. Mode I, Mode II, Mode III and Mixed-Mode I-II were, respectively, obtained from specimens submitted to double cantilever beam, end notch flexure, Edge Crack Torsion and mixed-mode bending tests. Two different loadings were applied to the edge crack torsion specimens: the original and the modified edge crack torsion test. Scanning electron microscopy, analytical and numerical analysis were used to identify and separate fractographic features and to establish the differences between the various modes of fracture. Scanning electron micrographs of fractured surfaces showed that the most predominant fractographic features in Mode I and Mode II are the large amount of fibre pull-out and the cusps markings, respectively. Mode III characterisation shows that some limited Mixed-Mode II-III appear in both ends of the edge crack torsion specimen on delamination initiation and growth, but a predominant Mode III delamination exists in the middle of the specimens.
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