Metastable Al-Mn phases formed by ion-beam mixing

Abstract
The phases produced by ion‐beam mixing of Al/Mn layers were examined as a function of mixing temperature between 30 and 200 °C for 16 at. % Mn. After intermixing of the layers at either 30 or 60 °C with 1×1016 Xe/cm2 at 400 keV, electron diffraction showed amorphous phase formation. However, ion‐beam mixing at 100 or 200 °C produced the icosahedral Al(Mn) phase. The crystalline phase Al6Mn can also be formed near the sample surface by ion mixing appropriate concentrations at elevated temperatures. Annealing at successively higher temperatures produced the transformation sequence: amorphous → icosahedral → Al6Mn, which indicates that the icosahedral phase is more stable than the amorphous phase.