Abstract
The intermetallic phases are analysed in recycled aluminium alloy with chemical composition Al-2.2Cu-1.7Mg-1.1Ni-0.2Cr-1.1Fe-0.2Mn-0.9Si-0.2Ti-0.3Zn (wt. %) and its mechanical properties are compared to those of industrially produced aluminium alloys with similar chemical composition. The structure of the alloy is composed of aluminium based α-Al) dendrites and multiphase interdendritic region. During heat treatments the nucleation and growth of fine precipitates of Mg₂Si, Al₂Cu, and Al₂CuMg intermetallic phases are observed in the α-Al solid solution. The interdendritic region contains several intermetallic phases with different size and morphology. The major intermetallic compound identified in this region is Al₉Fe(Ni,Si) and minor phases are Mg₂Si, Al₄Cu₂Mg₈Si₇, Al₄CuMg₅Si₄, AlCuMg, (Cu,Al)₂Mg, Al₇Cu₄Ni, Al-Cu-Ni, and Al₅(Fe,Cr)Si. After heat treatments the ultimate tensile strength varied between 396 and 421 MPa, 0.2% yield strength between 305 and 372 MPa, and elongation between 8 and 19%. The ductility of the alloy decreased with increasing annealing time and temperature.

Key words
recycling, wrought aluminium alloy, microstructure, phase analysis, mechanical properties

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