Akademik Veri Yönetim Sistemi
INTERNATIONAL JOURNAL OF METALCASTING, cilt.17, sa.2, ss.717-739, 2023 (SCI-Expanded)
The semi-solid metal forming techniques have been
researched for a long time to obtain near-net shape
products from aluminum alloys. Most of the effort was
devoted to the casting alloys such as A356 and A380 to
develop an alternative technique for high pressure die
casting process. In this study, the cooling slope casting
technique, which is an unorthodox approach to produce
semi-solid feedstocks for wrought aluminum alloys, and the
results of the following thixoforming processes were
investigated thoroughly for 7075 aluminum alloy.
According to the parameters studied and obtained results,
the lowest possible casting temperature and mild tilt angle
parameters were found to give the best outcomes for the
produced feedstocks’ physical and microstructural properties.
No significant difference was observed depending on
the slope length due to the employed low superheat during
casting processes. Reheating processes of the produced
feedstocks revealed that gradual depletion of Al from the
intergranular region and the migration of Cu to the Aldepleted
zones forms the partial melt, and the average
grain size of the reheated specimens dramatically increases
after 40 min of reheating at selected reheating temperature.
The average shape factor, grain size, and density
values of the specimen selected for thixoforming processes
were around 0.82, 96 lm, and 2.67 g/cm3, respectively.
After the thixoforming processes, the maximum hardness
attained was around 120 HB and a gradual decrease was
observed by increasing reheating durations in both measured
hardness and density values. The tensile properties
were also investigated, and the results were found
promising after the optimization of the forming pressure
and reheating duration except for the elongation values.