The toughening of Al-Cu-Fe(-B) quasicrystals by Sn particles

The effect of soft Sn particles on the room temperature mechanical properties of as-cast Al-Cu-Fe(-B) quasicrystalline (QC) matrix composites has been studied by compression and three-point bending tests on notched specimens. Microstructural investigations indicated that the Sn particle size in the as-cast composites increased linearly with the volume fraction. The addition of about 10 vol.% Sn enabled a twofold increase of the strength for the cast Al-Cu-Fe and a threefold increase of the fracture toughness for the cast Al-Cu-Fe-B composites. The enhancement of the strength was attributed to micro-crack impediment and crack bridging mechanisms in the as-cast QC matrix composites with small and large Sn particle sizes, respectively. (C) 2004 Elsevier B.V. All rights reserved.