Effect of Mechanical Alloying on the Microstructural Evolution of Al60Cr30Si10 Alloys Processed by Spark Plasma Sintering

Abstract

In this study, Al, Cr and Si fine powders were alloyed by planetary ball milling to investigate their microstructural evolution, following their mechanical alloying behavior. The formation of Al(Cr) supersaturated solid solution by the Cr grains embedded in Al-matrix, which contributed substitutional structure is discussed in relation to their structural evolution in accordance with the distortion of a crystal lattice. The compacts of Al–Cr–Si alloys were prepared by rapid sintering within a short time by dense consolidation above the density of 99.9% as the formation of intermetallics, except in the case of the distribution of single-phases induced by the Al-melting. The formation behavior of intermetallics was dominated by dependence on the structures of the milled-powder and subsequent sintering temperature. To estimate the consolidated behaviors of compacts, various approaches derived from TEM and XRD analysis were taken to obtain microstructural evidences of the inter-diffusion, following the presence of thermally stable intermetallics.