The behaviour of metal matrix composites during temperature cycling

✍ Scribed by S.M Pickard; B Derby

• Publisher: Elsevier Science
• Year: 1991
• Tongue: English
• Weight: 449 KB
• Volume: 135
• Category: Article
• ISSN: 0921-5093
• DOI: 10.1016/0921-5093(91)90564-4

✦ Synopsis

Commercial purity aluminium reinforced with SiC particles has been used to model the behaviour of metal matrix composites (MMCs) during thermal cycling. Above a critical temperature amplitude of about 150 °C an acceleration in creep under the load occurs. This is accompanied by a reduction in the creep stress exponent n from 15 to 1. The reduced stress exponent leads to a superplastic deformation behaviour with extensions in excess of 150% recorded. Transmission electron microscopy studies of the deformed microstructures show an essentially constant dislocation structure between as-received MMCs and those after 90% strain. The deformation microstructures were free of substructures such as polygonised cells characteristic of the recovery creep in monolithic alloys.