In this investigation the effects of material, structural and testing parameters of carbonepoxy braided composite tubes were analysed with respect to their performance in crushand impact conditions. An original method of manufacturing the composite tubes withvacuum infusion together with an expandable foam core to form multi-cellularstructures was used. Low cost, 24k tow carbon fibre braids were used and theirperformance was compared with that of the more expensive l2k tow size fibres. Thespecimens produced were axially crushed at constant quasi-static low velocities and athigher impact velocities using an instrumented falling weight machine. Loaddisplacement data gathered from such tests were used to evaluate the test specimenswith respect to their specific energy absorption values. The effects of a number ofparameters including fibre tow size, braid architecture, resin content and loading typewere evaluated.From the experimental results analysed from the test specimens it can be concludedthat: -The 24k fibre showed lower specific energy absorption values than specimensmade from l2k fibre.Epoxy resin content rather than epoxy resin type can significantly affect thespecific energy absorption values.In general, specimens tested in impact loading exhibited lower specific energyabsorption values than the same specimens test in quasi-static crush.A reasonably good correlation between global density and specific energyabsorption for the type of structures examined was found
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