AL BASED QUASICRYSTALLINE NANOCOMPOSITES

MARINA GALANO; WEIHAO GU; NICHOLAS ROUNTHWAITE; FERNANDO AUDEBERT; GEORGE SMITH

Glasgow

Congreso; EUROMAT 2009; 2009

Al based quasicrystalline nanocomposites which have a microstructure composed of nano-quasicrystalline particles embedded in an -Al matrix exhibit high strength in comparison with commercial Aluminium alloys. In particular, Al-Fe-Cr-Ti nanocomposites produced by melt spinning [1] showed high strength at elevated temperatures. In early works [2], it was observed that the substitution of Ti by Nb increased the stability of the quasicrystalline phase delaying the microstructural transformation to higher temperatures. Thus, these nanocomposites containing Al-Fe-Cr-Nb quasicrystals have become promising new high strength nanocomposites to be applied at elevated temperatures in the automotive and aeronautical industries. In order to obtain the bulk Al-Fe-Cr-Nb nanocomposites for industrial applications extruded bars from atomised powder atomisation have been produced. Different mixtures of atomised pure aluminium and nanoquasicrystalline powders were used. The microstructure of the atomised powders and extruded bars was characterised by means of XRD, SEM, TEM, and EDX and DSC. Mechanical properties have been studied by means of microhardness and compression tests. The relationship between processing, microstructure and properties is being discussed. The extruded bars maintained good mechanical properties similar to the reported for the as melt spun ribbons [3], thus, offering a feasible alternative for industrial applications.