Effects of sonoprocessing on microstructure and mechanical properties of A390 aluminium alloy

Abstract

Ultrasound is defined in terms of human hearing and it is a sound having a frequency higher than that to which the human ear can respond. The attempts to use the ultrasound at casting process have been carried out and there are a lot of study results on grain refinement on microstructure of casting alloys. However, these studies almost have been focused on mould vibration at solidifying melts of solid and liquid coexistence temperature. In this study, high intensity ultrasound was injected in aluminium full melts, especially A390 alloy, to evaluate the effect of ultrasound on microstructure and mechanical properties of castings. The effect of ultrasonic injection on melts could be summarised as follows: reduction of mean size of primary silicon, variation of phase distribution, improvement of solute homogeneity and mechanical properties.