Influence of solution temperature on eutectic structure and elevated-temperature mechanical properties of super-gravity solidified Al-Cu-Ce alloy

The influence of solution temperature on microstructure and mechanical properties in super-gravity solidified Al-Cu-Ce alloy was investigated. Noted that the formation of eutectic Al8CeCu4 phase is able to affect the precipitation behavior. Both heterogeneous and homogeneous nucleation of the precipitates occur during aging, leading to the formation of disk-like precipitates (Al-Al8CeCu4 interface) and needle-like precipitates (grain interior), which contributed to the significant enhancement(similar to 53 % higher than the super-gravity solidified sample) of tensile strength of 204.1 +/- 3.8 MPa at 300 degrees C. However, micro-cracks initiated preferentially in the vicinity of the eutectic colony boundaries mainly due to the brittleness of the spheroidized Al8CeCu4 phase, leading to a slight decrease in elongation.