The effect of ceramic type reinforcement on structure and properties of Cu-Al2O3 composites

The purpose of this paper is to elaborate on mechanical alloying conditions for a composite powder consisting of copper and brittle aluminium oxides. Detailed analysis of the Cu-Al2O3 powder mixture structure obtained in the mechanical alloying process allows for the study of the homogenization phenomena and for obtaining grains (in composite form) with a high degree of uniformity. The Cu-5vol.%Al2O3 composites were obtained by means of the spark plasma sintering technique. The results presented herein were studied and discussed in terms of the impact of using a different form of aluminium oxide powder and a different shape of copper powder on composite properties. Research methodology included microstructure analysis as well as its relation to the strength of Cu-Al2O3 interfaces. It transpires from the results presented below that the application of electrocorundum as a reinforcement phase in composites decreases porosity in the ceramic phase, thus improving thermal properties and interfacial strength.