Microstructure of a composite with a quasicrystalline phase fraction obtained by directional solidification of Al₆₁Cu₂₇Fe₁₂ alloy

Abstract

The microstructure of a composite containing a quasicrystal phase, i.e. so-called crystal–quasicrystal (CQ) composite, was studied. The CQ composite was obtained by the Bridgman method via solidification of Al₆₁Cu₂₇Fe₁₂ alloy (numbers indicate at%). The process was conducted at a pull out rate of v = 0.07 mm/min. The average temperature gradient in the heating zone was 43 K/cm. The composite matrix consisted of cubic β phase Al(Fe, Cu), with reinforcement of λ-phase rod-shaped fibres surrounded by a quasicrystal icosahedral ψ phase, which also existed in the fibre core. The fibres were rhomboidal in cross-section. The composite was studied using X-ray and electron diffraction, light-optical and scanning electron microscopy (SEM), X-ray topography and Laue diffraction.

Keywords:

• quasicrystals
• composite materials
• microstructure
• aluminium alloys
• directional solidification

Acknowledgements

The work of J. Krawczyk was supported in part by the UPGOW Programme at the University of Silesia, co-financed by the EU within the European Social Fund.