Synthesis and mechanical properties of cast quasicrystal-reinforced Al-alloys

We report on the preparation and mechanical properties of Al-based-composit es with quasicrystalline particles as reinforcement. Al-Mn-Ce/Fe and Al-Mn- Pd bulk samples were synthesized by die casting into a copper mould at mode rate cooling rate. Thin ribbons were prepared by melt-spinning as a referen ce state for the phase formation under most rapid quenching conditions. Mic rostructural analysis was done using X-ray diffraction, scanning and transm ission electron microscopy as well as calorimetric methods. Significant dif ferences in the phase formation, the composite microstructure and the therm al stability of the microstructure were found for different alloy compositi ons. The deformation behaviour was characterized by constant-rate compressi on tests at room temperature for a number of alloy variations yielding exce llent properties compared to conventionally produced Al-alloys. The mechani cal properties vary within a wide range of strength and ductility as a func tion of the quasicrystal volume fraction and their morphology. Also first t ests at elevated temperatures were carried out, revealing a promising high temperature stability of the composite. (C) 2001 Acta Materialia Inc. Publi shed by Elsevier Science Ltd. All rights reserved.