Quantitative analysis of Al2O3 particles in Al3Ti/Al2O3/Al composites

This paper concerns the quantitative relation between the microstructure and mechanical properties of Al3Ti/Al2O3/Al composites fabricated by powder metallurgy. Microhardness measurements and a quantitative evaluation of Al2O3 particles in composites prepared using different powder consolidation techniques were made. Characterization of the Al2O3 particles was done in terms of size and volume fraction measured on sections. Voronoi tessellations and a linear covariance method [T. Wejrzanowski, et al., Image Anal. Stereol. 20 (Suppl. 1) (2001) 71–6] were used for a description of the spatial distribution of particles. The results revealed differences in the volume fraction of the Al2O3 phase. No significant differences in the size and size distributions of the particles were detected. The spatial arrangement examinations showed a random distribution of particles in each composite. Despite this, differences in the homogeneity of the particle dispersion were found. The results prove the influence of the volume fraction of Al2O3 particles on the microhardness. A significant influence of the homogeneity of the particle arrangement on the variation of the microhardness was also demonstrated.