Structural performance of nanoquasicrystalline composites based on Al-Fe-Cr-alloy: Synthesis and key characteristics

The present study is primary addressed to structural performance of nanoquasicrystalline composites based on Al-Fe-Cr alloy and, particularly, their thermal stability and mechanical behaviour in response to heat treatment. Several kinds of semi-products and bulk-shaped composites have been produced using rapid solidification by melt spinning, powder atomization, hot extrusion, and cold-spraying. All kinds of as-received products comprised nano-sized quasicrystalline particles embedded in Al matrix although their fraction volume and the other structural parameters of composites were found to be rather different and dependent on synthesized strategy. Evolution of structure in response to heat treatment of the each kind of product and synthesized composite have been studied by means of precise method of differential scanning calorimetry, X-ray analysis, and electron microscopy. Mechanical parameters of as received and heat treated composites have been examined by using indentation technique and discussed by considering classical strengthening mechanisms. As to structural stability of ternary Al-Fe-Cr alloy, cold-spraying technique shows essential advantage in remaining quasicrystalline phase and, hence, mechanical properties compared to that provided by currently employed hot extrusion.