HIGH-TEMPERATURE CREEP RESISTANCE OF METAL-MATRIX COMPOSITES

A new approach to the effective creep resistance of two phase composit es at high temperature has been developed through direct analogy betwe en creep resistance and field properties (or transport properties). Th e new approach can take into account implicitly the effects of size, s hape, of orientation, and distribution of the reinforcement through th e topological parameters. Therefore, it can be applied to a two phase composite containing particles with any size, shape, orientation, and distribution. Compared with Saltzer and Schulz's model, which can only be applied to composites with low volume fraction of the reinforcemen t, the present approach can predict the variation of creep resistance of two phase composites over the whole range of microstructures (from completely discontinuous to completely continuous) and volume fraction s, and more importantly is in better agreement with experimental resul ts. In addition, the effect of particle distribution on the effective creep resistance of two phase composites has been demonstrated quantit atively. The effective deep resistance increases with increasing conti guity of the reinforcing phase. (C) 1997 The Institute of Materials.