INTERFACES IN COMPOSITE-MATERIALS

The mechanical functions of the fibre/matrix interlayer as well as its quantitative parameter dependencies and their influence on the proper ties of the composite system are discussed, with the theoretical model being considered under realistic conditions. Corresponding to that a number of interface structure phenomena of some advanced composite mat erials, revealed by high voltage and high resolution electron microsco py, are discussed with respect to their relevance to tile control of c omposite properties, including complex interlayer systems, which are p roduced by fibre coating as well as by chemical solid state transport and exchange reactions. The effects of hooking-together, binding, inte rnal microcracking, and sublayer formation are demonstrated, and in so me cases correlated with the mechanical behaviour of the materials as revealed by in situ tensile tests.