COMPRESSIVE PROPERTIES OF CONTINUOUS ALUMINA FIBER EPOXY AT 295-K AND 77-K

The compressive behaviour of a continuous alumina fibre (FP) reinforced epoxy depends on fibre orientation and temperature. FP/epoxy with reinforcing fibres parallel to the loading direction has the highest Young's modulus and the lowest ultimate strain. Fibres in the transverse direction result in the lowest modulus but the highest ultimate strain. The behaviour of the crossply laminates is intermediate. The compressive strengths of FP/epoxy at 77 K are higher than at 295 K, while the Young's moduli remain similar to those at 295 K except for an 11% increase in the O-degrees laminae and an 81% increase in the 90-degrees laminae. Fibre breakage across the specimens resulting from shear failure dominates for the 0-degrees laminae at 295 K; fibre delamination dominates at 77 K. Delamination between fibres caused by shear failure throughout the entire thickness of specimens is the typical failure mode for the 90-degrees laminae at 295 K and 77 K.