Abstract
The heat treatment of (Al₆₃Cu₂₅Fe₁₂)₉₉Ce₁ alloy was performed at 650, 750, and 850 °C for different holding times. The effects of the heat treatment process on the alloy's microstructure and thermal expansion properties were studied. Results revealed that the cast alloy contained β-Al_0.5Fe_0.5 phase (β-phase), Al2Cu3 phase, Al13Ce2Cu13 phase, and icosahedral quasicrystal I-phase (I-phase). After holding at 750 °C for 6 h, the alloy contains only an I-phase and a small amount of Al₁₃Ce₂Cu₁₃ phase. When the heat treatment temperature continued to increase, the I-phase was partially decomposed. After heat treatment, the thermal expansion coefficient of the alloy decreased obviously. Compared with as cast, the thermal expansion coefficient of the alloy decreased by about 10 % after holding at 750 °C for 6 h. The results show that the Al-Cu-Fe-Ce alloy with excellent microstructure and properties can be obtained by an appropriate heat treatment process.

Key words
heat treatment, quasicrystal I-phase, microstructure, coefficient of thermal expansion

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