Increasing Performances of En AB-46000 by Squeeze Casting

Abstract

The evolution of the mold temperature during squeeze casting of EN-AB46000 aluminum alloy has been correlated with the final mechanical performances of cast ingots. Starting from a material model which expresses hardness and yielding stress of cast aluminum alloys as a function of the cooling rate during the melt solidification, an experimental approach has been used to provide a useful tool for process monitoring. As a result, the mold temperature increase during the melt squeezing phase is directly correlated with the main mechanical and microstructural parameters. Experiments were made by squeeze cast small cylinders (14 mm in diameter and 18 mm height) at different values of squeezing pressure, mold pre-heating temperature, and melt temperature. Microscopic observations of the sample sections were made as well as hardness measurements and indentation tests. In conclusion, because of the material solidification, a temperature gradient has been observed in the sample which can be directly related with the aluminum alloy dendrite size and, in turn, with microhardness and yielding stress.