Phase transformations induced by nitridation of quasicrystalline AlCuFeB powders

Nitridation is an important reaction which has never been investigated for Al-based quasicrystals. Here we show that AlCuFeB quasicrystalline particles undergo phase transformations upon annealing at high temperature in pure nitrogen. A thick nitride layer grows on the surface of the particles, and Al depletion in the bulk results in transformation of the quasicrystalline phase first into the cubic β-phase and then into the monoclinic λ-phase. The kinetics of this transformation is much faster than that of oxidation.