Characterization of Aluminium Oxide (FP) Fibre Reinforced Al-2,5L_I-Composites

Abstract

Metal matrix composites based on Al₂O₃-fibre reinforcements are gaining increasing attention for structural application. However, the data base concerning its mechanical properties and microstructural characterization remains limited. For the present study an A1₂O₃-fibre (FP-fibre from Dupont) reinforced Al-2,5 Li composite has been investigated. Continuous fibre reinforcements, unidirectional in the 0° and 90°-direction were used for the investigation. Processing of the material was performed by vacuum melt infiltration at LCS, Bordeaux.

Transmission electron microscopy was performed in order to study the fibre/matrix interface. Precipitation free areas around the fibres containing any δ’ particles, which in turn are present in the matrix, were found. For mechanical characterization tensile and compressive tests were performed. In order to get sufficiently good results a special MMC-related test equipment was designed. The best results were achieved, when cylindrical hour-glass shaped specimens were used. Fatigue testing of the metal matrix composites showed, that with fibre reinforcement a pronounced improvement of the fatigue behaviour can be achieved.