3D Characterisation of the Fe-rich intermetallic phases in Al-5%Cu alloys by synchrotron X-ray microtomography and skeletonisation

Synchrotron X-ray microtomography and skeletonisation method were used to study the true 3D network structures and morphologies of the Fe-rich intermetallic phases in Al-5.0%Cu-0.6%Mn alloys with 0.5% and 1.0% Fe. It was found that, the Fe-phases in the 1.0%Fe alloy have node lengths of 5-25m; while those in the 0.5%Fe alloy are of 3-17 m. The Fe-phases in the 1.0%Fe alloy also developed sharper mean curvature with wider distribution than those in the 0.5%Fe alloy. Combining SEM studies of the deeply-etched samples, the true 3D structures of 4 different type Fe-phases in both alloys are also revealed and demonstrated.