Solidification relationship between the primary–Al grain and α–Al15(Fe,Mn)3Si2 intermetallic phase in the 6082 wrought Al alloy

This study investigates the orientation relationship between primary-Al and α–Al 15 (Fe,Mn) 3 Si 2 in Wrought Al alloy 6082, focusing on two phase structural interactions. Transmission electron microscopy (TEM) was employed to confirm the alignment between the two main phases. The work showed the formation of primary-Al and α–Al 15 (Fe,Mn) 3 Si 2 intermetallics, where α–Al 15 (Fe,Mn) 3 Si 2 nucleates around the primary-Al intergranular regions. TEM confirmed specific orientation relationships (111) α-Al // (202) α-Al15(Fe,Mn)3Si2 and (200) α-Al // ( 2) α-Al15(Fe,Mn)3Si2 under primary-Al zone axis [110]. The study suggests that the solidification process of primary-Al and α–Al 15 (Fe,Mn) 3 Si 2 follows a coupled growth mechanism, where the formation of primary-Al influences the evolution of α–Al 15 (Fe,Mn) 3 Si 2 leading to the observed orientation relationships. The proposed mechanism suggests that the growth kinetics and the matching close-packed planes (110) and (113) play a critical role in the orientation dependent growth of the phases.