Analysis of Gap Formation at Mold-Shell Interface during Solidification of Aluminum Alloy Plate

摘要

Thermal contraction of the casting and the thermal expansion of the mold result in gap formation at the mold-casting interface, which affects greatly the heat transfer between the mold and casting. Information on the movements of the mold and casting during solidification and cooling is also the basis for the investigation of the casting deformation. Movements of the casting and mold were analyzed simultaneously using coupled thermo-mechanical contact boundary model for the plate casting of aluminum alloy. The calculated displacement and temperature distributions of the casting and mold were compared with the previous measured data. It was confirmed that the mold and the casting moved together until the air gap formed by the calculation. Comparing the air gap curve with the displacement curve of the casting just before and after air gap formation made it apparent that the growth of the air gap was mainly due to contraction of the casting because the change in the mold displacement was not significant. Gap formation time increased with increase in initial mold temperature.