CRUSHING MECHANISM OF CARBON-FIBER PEEK COMPOSITE TUBES

In the past two decades the specific energy absorption capability of p olymer composite tubes has increased steadily by using advanced fibres and tough resin matrices. Tubes based on carbon fibres in a matrix of poly(ether ether ketone) (PEEK) have displayed the highest specific e nergy absorption capability, of 180 kJ kg(-1). The various factors con tributing to the superior performance of carbon/PEEK tubes have been i dentified by studying the crushing process using a step-by-step crushi ng method. Attempts have been made to correlate microfracture features of the crush zone with energy absorption capability. The superior :pe rformance of carbon fibre/PEEK tubes is attributed mainly to (a) the h igher fracture toughness of PEEK matrix composites, (b) splitting of f ronds and (c) the large number of fibre fractures.