The effect of globular microstructure size on the mechanical properties in reheating process of aluminum alloys

One of the important steps in semi-solid forming is the process of reheating raw materials to the semi-solid state. This process is not only necessary to achieve the required semi-solid state of the billet, but also to control the microstructure of the billet. In the reheating process, the globule size is determined by the holding time of the final reheating step. Therefore, some experiments to investigate the relationship between the mechanical properties and the holding time in the last heating step were performed. The alloys used in this experiment were 357, 319, and A390 alloys. The experiments of reheating were performed using an induction heating system with a capacity of 50 kW. This article shows the evolution of the microstructure according to the holding time of the last reheating stage. Furthermore, to evaluate the effect of globule size as determined by holding time of the final reheating step, uniaxial tension tests were performed. The stress-strain curves were plotted according to the holding time, and a relationship between the microstructure and the flow stress of semi-solid material was formulated.