Mechanical and Corrosion Behaviors of the Casting Al-Cu Alloy Modified by Nano-Scale PrxOy and LaxOy
The mechanical properties and corrosion behaviors of the casting Al-Cu alloys were investigated. The proportion of the two modifiers (PrxOy and LaxOy) has effects on the mechanical properties and the electrochemical corrosion behavior of the casting Al-Cu alloy. The ultimate true tensile strength of the Al-Cu alloy modified only by LaxOy is the highest (616.0 MPa). The fracture strain of the Al-Cu alloy modified by PrxOy and LaxOy is the highest (12.3%). The Al-Cu alloy modified by PrxOy has better corrosion resistance than any other Al-Cu alloy. The prominent mechanical properties should be attributed to the finer crystal grains and more homogeneously distributed nano-scale phase precipitates. The existence of continuous and compact protective Al2O3 and RE-O films enhanced the corrosion resistance of the modified Al-Cu alloy during the corrosion process.