Characterization of Rapidly Solidified Al_(65)Cu_(20)Fe_(15) Alloy in Form of Powder or Ribbon

摘要

The Al_(65)Cu_(20)Fe_(15) alloy has been prepared by conventional casting to the mould and by melt spinning or atomisation techniques. The melt spun ribbon was in the form of fragmented, brittle flakes, atomized powder has spherical shape with average size 17.2 μm. It was found that icosahedral Ⅰ-phase was the main phase in all types of prepared samples. In the conventionally cast alloy the following phases have been identified additionally: λ-Al_(13)Fe_4, τ-AlCu(Fe) and η_2-AlCu. In the melt-spun ribbon the formation of η_2 is avoided, while in the atomised powder the Ⅰ-phase coexists with small amount of copper rich τ-phase. In the cast ingot the Ⅰ-phase form as a product of peritectic reaction λ + L, while in the ribbon and in the powder quasicrystal solidified from the undercooled melt as primary phase and next metastable cubic τ-AlCu(Fe) was formed at the interdendritic areas. Single Ⅰ-phase grains of the sizes about 1 μm are observed in the ribbon close to the wheel side.