Metallographic investigation of reinforcement damage in creep of an AZ 91 matrix composite

Specimens of the AZ 91 composite were creep tested to failure and then exam ined internally to evaluate the significance of fibre cracking and/or break ing. It is demonstrated that the occurrence of fibre damage is influenced s ignificantly by the nature of the procedures used to prepare samples for su bsequent metallographic observations. Using an improved procedure, it is sh own that the cracking or breaking of fibres is a relatively unimportant pro cess in the creep failure of the AZ 91 composite. (C) 1999 Elsevier Science B.V. All rights reserved.