Characterization of interphase properties: Microfatigue of single fibre model composites

Tests on single fibre model composites are particularly sensitive to the properties of the interphase. A self made equipment for measuring hysteresis curves (force as a function of displacement) is introduced and subjected to a feasibility test. End-embedded single fibre model composites were exposed to cyclic tension and compression loading. Long-term, relaxation and progressive load tests are performed on sets of single fibre model composites. Glass and PBO fibre reinforced epoxy, polyamide, polypropylene, and cement matrices were investigated in the virgin state or after water treatment. The data are presented and discussed in terms of force amplitudes, stiffnesses or energies as a function of time or cycle number.