Effect of Homogenization Temperature on the Microstructure and Property of 6061 Aluminum Alloy with Erbium

Abstract

The microstructure and mechanical properties of as-homogenized 6061 aluminum alloy with 0.2wt.% Er were investigated. The microstructures of the as-casted and homogenized alloys were analyzed using optical microscopy (OM) and scanning electron microscopy (SEM). Energy dispersion X-ray spectroscopy (EDS) was used to analyze the phase chemical composition. The results showed that the homogenizing treatment had a significant influence on the precipitate morphology of the alloy. With increasing homogenization temperature, the long strip-like Fe-rich grain distributed on the boundary phase became discontinuous and sparseness, transforming to short rod and granular shape. In addition, the Fe-rich phase with a large fish-bone structure became smaller. During homogenizing treatment, a large number of dispersive Mg2Si phase appeared inside grains, and large number of the phases containing Er were dissolved into the matrix.