Synthesis of quasicrystalline phase by mechanical alloying of Al70Cu20Fe10

An icosahedral phase (i-phase) has been synthesized by mechanical alloying of an elemental blend of Al70Cu20Fe10. Mechanical alloying of Al and Fe in the stoichiometric ratio of 3:1 and continued milling after the addition of Al and Cu to yield the nominal composition of Al70Cu20Fe10 does not result in the i-phase formation which requires subsequent annealing at 600 degree s C for 4 h for its formation. h single i-phase cannot be obtained even aft er annealing. In all cases, an Al(Cu, Fe) solid solution (beta phase) has b een found along with the i-phase. The i-phase appears to form by a peritect oid type of reaction between the beta phase and Al2Cu. The electrical resis tivity of the nanocrystalline i-phase obtained in the present study was rou nd to be about 2-3 orders higher than that found in thin films and it shows semiconducting behaviour.