A synchrotron X-ray study of a Ti/SiCf composite during in situ straining

X-ray synchrotron radiography and high spatial resolution strain measuremen ts have been combined to build-up a picture of the micromechanics of the da mage that occurs, and the internal stress that causes it, within a Ti/SiC m onofilament composite test-piece that was progressively strained in situ on the beam-line. The sample was designed to include a row of fibre ends with in the test-piece. The radiographs show that fibre breakages occur during s training, even in the vicinity of the fibre ends. Axial and transverse stra in measurements were made along each fibre in the composite as the load was progressively increased using a small X-ray spot size. In the present case interfacial sliding is believed to occur by slipping in or near the 4 mum carbon coating of the SCS-6 fibres. In order to interpret the strain measur ements the predictions of a simple axi-symmetric finite element model of th e composite are compared with the measured strains. (C) 2001 Acta Materiali a Inc. Published by Elsevier Science Ltd. All rights reserved.