Formation and properties of Al composites reinforced by quasicrystalline AlCuFeB particles

Abstract

Abstract\n Al-based composites reinforced by icosahedral (i-) Al59Cu25.5Fe12.5B3 quasicrystalline particles were prepared by solid state sintering. It is found that Al diffusion from the matrix to the quasicrystalline particles induces phase transformation into the ω-Al7Cu2Fe tetragonal phase. In order to preserve the i phase, we use an oxidation pre-treatment of the particles and study its influence onto the kinetics of the phase transformation (Al + i → ω) as a function of the temperature by high energy X-ray diffraction. We show that the oxide layer acts as a barrier reducing efficiently the diffusion of Al up to a sintering temperature of 823 K, allowing the control of the phases in the composites. The mechanical properties and the friction behaviour of the composites are investigated and show the negative influence of the oxide on the interface strength.