Microstructure and mechanical properties of Al/Al₄C₃/Al₂O₃ composite

Microstiucture and mechanical properties of Al₄, C₃ and Al₂ O₃ dispersion strengthened aluminum composite fabricated by mechanical attrition and hot-pressing consolidation method were studied. It was shown that fine well developed Al₄C₃ stick and equiaxed γ-Al₂O₃ dispersoids with total content of about 6.6 v% uniformly distributed within the Al grains or along the grain boundaries. The Al/Al₄C₃ and Al/Al₂O₃ interfaces are very clean and well bonded at atomic level, but have no fixed orientation relationships between the dispersoids and the aluminum matrix exists. At ambient and especially elevated temperatures, strength and stiffness of the composite are much higher than that of P/M Al and even better than that of the 15 v% SiC_w/Al composite.