The phase equilibria of the Al-Cu-Fe quasicrystalline phase (#PSI# phase) is ocmplex and conventional crystal growth techniques like the bridgman and Czochralski methods are not applciable in preparation of large crystals.large single grains of the #PSI# phase been have prepared by either slow cooling or isothermal anneals.In the later technique,are melted ingots were subjected to either single or multiple heat treatments between 825 and 840 deg C to encourage grain growth.Following heat treatment,grains of the icosahedral phase are found either as isolated pentagonal-facted crystals within the ingot or within clusters of intergrown grains.the growth of the large-grains is independent of the sample processing history of the sample,is facilitates by the presence of liquid at the growth temepratures and is constrained by the phsysical dimension of the ingot.the microstructure of both grain types is similar containing a minor quantity (on the order of 5-10
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