Measurement of the variation of interfacial shear stress in Ti/SiC composites as a function of temperature

摘要

Ti-6Al-4V/SiC fibre reinforced composites have been identified for use in aeroengine applications that typically experience temperatures of ～350°C in service. Critical to their performance is the interfacial shear strength between matrix and fibres. We have used X-ray synchrotron strain mapping to monitor the variation in axial fibre strain in a single fragmented fibre in a Ti-6Al-4V matrix at 25, 125 and 250°C. The variation in interfacial shear stress along the fibre/matrix interface was inferred from the rate of change of the fibre strain along the fibre. In this way the frictional sliding stress of a pristine fibre interface was evaluated as a function of temperature.