Microstructure and mechanical properties of Al-Cu-Ce alloy

Microstructure and mechanical properties of Al-Cu-Ce alloys with different Cu and Ce contents were investigated by means of X-ray diffraction(XRD), optical microscope(OM), scanning electron microscopy(SEM), energy dispersive spectrometer(EDS) and mechanical property testing. The results show that the microstructure of Al-14Cu-7Ce alloy consists of α-Al+Al 8CeCu 4 eutectic. But for Al-10Cu-5Ce and Al-18Cu-9Ce alloys, the primary phases of α-Al and Al 8CeCu 4 are also found, respectively, besides α-Al+Al 8CeCu 4 eutectic. The as-cast Al-14Cu-7Ce alloy exhibits excellent heat resistance, the tensile strength of which remains about 360 MPa after annealing at 550°C for 3 h. The decrease of strength is observed in the alloy after annealing at higher temperature or for longer time because of the spheroidization of the eutectic Al 8CeCu 4 phase. A combination of good hot and cold plastic working ability with higher heat resisfance can be obtained for the Al-Cu-Ce alloys after spheroidization annealing.