Determination of process parameters of semi-solid metal casting and investigation of mechanical properties for Al2024 alloy

In this study, a wrought AA2024 aluminum alloy was shaped with thixo-casting technique which is one of the semi-solid metal forming processes. Billets produced by strain induced melt activation (SIMA) process were used in thixo-casting. In the semi-solid region, microstructural and mechanical property variations depending on the temperatures that corresponded to different liquid fractions (608 oC, 616 oC, and 619 oC), and 2.37 m/s ram speed have been investigated.In the billet production by SIMA process, with increasing cold deformation rate, the shape factor increases while the grain size decreases depending on temperatures. In the forming by thixocasting, at the temperature (608 oC) that corresponded to low liquid fraction the die cavity has not been fully filled by the semi-solid billet. The die cavity has been fully filled by semi-solid billet at high liquid fraction (60% and 65%). The mechanical properties of specimens which produced by thixocasting were found to be 50% lower than extruded + T6 condition specimen. The mechanical properties of the specimens which produced by thixocasting + T6 condition are almost same as specimens in extruded conditions.