Modification of eutectic Mg2Si in AlMg5Si2Mn alloy by pre-homogenization deformation treatment with different reduction conditions

The effect of a novel pre-homogenization deformation (PHD) treatment on the microstructure and mechanical properties of extruded AlMg5Si2Mn alloy was investigated. By introducing the cold compression prior to homogenization treatment, the brittle and interconnected eutectic Mg2Si phase in the as-cast AlMg5Si2Mn alloy transformed into fine and spherical particles uniformly dispersed in the aluminum matrix. As the amount of PHD increased, up to 10%, the size of the Mg2Si particles decreased and their sphericity increased in the extruded samples, resulting in a gradual increase in both strength and elongation after heat treatment. The mechanical properties of the PHD-treated AlMg5Si2Mn extrudates were compared with those of materials prepared using various casting and deformation processes, and the potential application to wrought products was discussed. [Display omitted] •PHD treatment was proposed to modify Mg2Si morphology of extruded AlMg5Si2Mn alloy.•PHD treatment accelerated spheroidization of eutectic Mg2Si in AlMg5Si2Mn alloy.•Tensile properties of AlMg5Si2Mn extrudates were improved by introduction of PHD.