Effect of Fibre Orientation on Mode-I Interlaminar Fracture Toughness of Glass Epoxy Composites

Abstract

The mode-I interlaminar fracture toughness (IFT) property of room temperature (RT) cured glass-epoxy (LY556/HY95 1) composites was studied using a double cantilever beam (DCB) test specimen with unidirectional fibre orientations of 0°, +450/-450, +600/-600 and 900 in the neighborhood of the crack zone. Three IFT data reduction techniques, viz.: (1) Modified Beam Theory (MBT), (2) Compliance Calibration Theory (CC) and (3) Modified Compliance Calibration Theory (MCC) were verified for the DCB data generated for 0° fibre oriented specimens. The fracture toughness property estimates were noted to be approximately the same for all three techniques. Only the MBT reduction procedure (as per ASTM) was used for other orientations. It was observed that the IFT increased as the fibre orientation was changed from 0° to 900 with reference to the direction of crack propagation.

Keywords

Mode-I interlaminar fracture toughness double cantilever beam delamination fibre orientation

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