Homogenization process of the intermetallic compound layers of Al-clad iron

A homogenization process was carried out with Al-clad iron by diffusion annealing at 600, 650 and 780 °C for times ranging from 2 to 72 h. The aluminum layer was completely consumed by about 4 h with the formation of different diffusion aluminides layers. The annealing treatment at 780 °C for 72 h resulted in the formation of a homogeneous Fe-Al alloy through the foil thickness. The evolution of phase formation was examined by SEM-EDAX and X-ray diffraction techniques. Wherever it was possible TEM analysis was used.