Effect of Cryomilling on Microstructure and Mechanical Properties of 7050 Aluminum Alloy

The 7050 aluminum alloy samples were prepared from as-atomized 7050 aluminum alloy powder through cryomilling, hot isostatic pressing, hot extrusion and T6 heat treatment. The influence of cryomilling on morphology, grain size and microscopic strain of aluminum alloy powder were analyzed by SEM and XRD. The influence of cryomilling on microstructure and mechanical property of the sample after heat treatment was analyzed by OM, EBSD, TEM, XRD, microhardness and tensile test. The results show that cryomilling can effectively refine the grain size of the material and increase the number of nano-precipitates in the matrix. Compared to the as-atomized powder, the mechanical properties of the 7050 aluminum alloy sample prepared by cryomillied powder are obviously improved