AbstractA stereometric method for digitising the fracture surface of unidirectional fibre composites is used to calculate the breaking height differences of each fibre to its six nearest neighbours. From this height distribution the overload profile along the fibres, the critical length, interfacial shear strength, and the characteristic strength of the fibres are derived. This method is applied to ceramic fibre reinforced aluminium matrix composites tested in three point bending.MST/3004