| Abstract: | The combined effects of pre-deformation and pre-aging on the mechanical properties of AlCu-Mg alloy with Sc and Zr addition were investigated. It is revealed that the introduction of pre-deformation can enhance the peak-aging strength, as well as tensile and yield strength, effectively due to the formation of finer and more dispersive precipitation. Pre-aging process before pre-deformation can increase the elongation while maintaining higher strength with a discontinuous distribution of precipitates at grain boundary. The precipitates of bean-like Al3(Sc, Zr) particles further strengthen the alloy via pinning the dislocations which are formed during pre-deformation process and hindering the dislocation motion. Furthermore, pre-deformation and pre-aging accelerate the kinetics of precipitation due to preferential sites provided by the dislocation and the increase of GPB zones' size and distribution. The synergism of pre-deformation and pre-aging achieves a combination of better mechanical properties and shorter peak-aging time. |
