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Abstract: Creep behavior of the unmodified and modified cast Al–Cu alloys was investigated at temperatures from 393 to 483K in the tension test. The creep resistance ability of the Al–Cu alloy modified by Pr x O y is almost 3–5 times as high as that of the unmodified Al–Cu alloy, which is attributed to a large number of nano-scale θ′ precipitates with high thermal stability in the modified Al–Cu alloy restricting and impeding the dislocation movement during the creep. The induction of a threshold stress in the analysis leads to a stress exponent of 5, which suggests that the creep behavior of both the present alloys is associated with the lattice diffusion-controlled dislocation climb (n =5). [Copyright &y& Elsevier]

Abstract: The corrosion resistance of the casting Al–Cu alloys was investigated by both the immersion test and electrochemical measurements. The results showed that the modified Al–Cu alloy by the nano-scale Pr x O y had better corrosion resistance than the unmodified Al–Cu alloy. A proposed mechanism for this phenomenon could be described as follows: the dominated existence of continuous and compact protective Al2O3 and Pr2O3 films enhanced the corrosion resistance of the modified Al–Cu alloy during corrosion, while no continuous and compact protective Al2O3 films led to the poor corrosion resistance of the unmodified Al–Cu alloy. [Copyright &y& Elsevier]