Evaluation of microstructure and mechanical characteristics of 2024 aluminum alloys with μ-Al2O3 additives produced via hydrostatic cyclic expansion extrusion with back-pressure

Grain refinement techniques are commonly used to produce enhanced materials with micro- and nanoscale grain sizes. This study investigates the severe plastic deformation of 2024 aluminum alloys reinforced with microparticles of alumina (Al2O3) using a new method based on hydrostatic cyclic expansion extrusion. Cuboid samples of aluminum 2024 were subjected to severe deformation at 20 °C through the pressing of a steel punch from the top and the application of back-pressure to the bottom part of the workpiece after the addition of the reinforcing powder. The mold design was created to facilitate both modes of operation. The experimental results were used to examine deformation behavior and flow patterns in the samples. Furthermore, the mechanical properties and microstructure of the processed samples were analyzed to determine the effects of the applied strain.