Microstructure and properties of 7475 aluminum alloy after equal-channel angular pressing

Equal-Channel Angular Pressing (ECAP) was successfully conducted on a 7475 aluminum alloy at temperatures from room temperature to 773 K up to an equivalent true strain of ~12 using routes C or BC. The grain size was refined to within the range from ~0.3 - 1.9 ?m by ECAP at these different temperatures. There appears to be a grain refinement limit which is dependent upon the precise pressing temperature. The results from tensile testing indicate that ECAP leads to a significant improvement of ductility in the experimental alloy while the yield and tensile strength are also slightly improved. This paper reports investigations of the microstructural characteristics and the mechanical properties of the processed aluminum alloy