Back Flow Creep Phenomena in Short Fibre Reinforced Aluminium Alloys

摘要

The present study investigates back flow after creep unloading of a squeeze cast metal matrix composite (MMC), for an AlZn11 matrix alloy reinforced with 8 volume-% Saffil fibres. The material was deformed to a certain amount of strain under a stress of 30 MPa. Then it was unloaded and the kinetics of back straining was measured. It was found that after unloading back straining occurs and strains accumulated which are significantly higher than expected for elastic unloading. It is shown that back straining of the MMC represents a creep process which is driven by the elastic strain energy stored in the fibres.