Experimental and modeling investigation on SiC_p distribution in powder metallurgy processed SiC_p/2024 Al composites

摘要

SiC_p/2024Al composites were fabricated through the powder metallurgy (PM) technique. The mixing process was modified by using a high ball to charge ratio (BCR), which resulted in improved homogeneity of the SiCp distribution, as well as enhanced tensile strengths of the as-pressed composites. A small particle size ratio of aluminum to SiC_p (PSR) and extrusion also improved the uniformity of the SiC_p distribution. The improvements by the three approaches were quantitatively analyzed using a critical volume fraction model. The model demonstrates that a small PSR and a large deformation ratio of aluminum particles were two essential factors of improving the homogeneity of the SiC_p. A homogeneity analysis using the Dirichlet Tessellation method provided an additional explanation for the model.