Al-Cu-Co single quasi-crystals obtained by the method of inclined front crystallization

An Al-Cu-Co alloy was obtained by the inclined front of crystallization method. During crystallization the alloy delaminated into three layers, two of which were single decagonal quasicrystals of different orientations and the third one was a mixture of two phase. The first quasi crystalline layer was formed in a peritectic reaction of an earlier crated single crystalline layer of an approximant, the second-grew directly from liquid. With the use of X-ray topography it was found that the planes of both quasicrystals are rotated of about 1 degree against each other.