Effects of water-restricted panel on the casting process of high strength aluminum alloy ingots

A comprehensive mathematical model, based on the commercial package FLUENT, was developed to describe heat transfer, fluid flow and solidification during the steady-state of direct-chill (DC) casting 7050 aluminum alloy ingots. In order to verify the mathematic model and boundary conditions applied in the simulation, the temperature fields of 180 mm × 360 mm 7050 ingots were calculated and compared to the experimental results during conventional casting and water-restricted panel applied casting. There was a perfect agreement between them. Based on the mathematic model and the boundary conditions which were verified, the temperature fields of ingot with different water-restricted panel position were investigated. The cooling rate of the ingot was decreased because the water-restricted panel removes the coolant from the ingot surface. The higher the panel position, the slower the cooling rate. The hot-tearing susceptibility of ingot during casting could be suppressed as the slow cooling rate of ingot profits the stress relieving. In addition, the sump depth is sensitive to the panel position, the higher the panel, the deeper the sump. The sump depth increases remarkably when the panel is applied above the sump bottom during conventional casting, while increases slightly when the panel is applied below it.