Liquid phase separation and monotectic structure evolution of ternary Al62.6Sn28.5Cu8.9 immiscible alloy within ultrasonic field

•Macrosegregation of Al–Cu–Sn alloy is effectively suppressed by ultrasound.•Spherical ternary (Al+θ+Sn) monotectic cells are formed within ultrasonic field.•Cavitation effect accounts for the microstructure variation.

Power ultrasound was introduced to investigate its effects on the liquid phase separation and monotectic solidification process of ternary Al62.6Sn28.5Cu8.9 immiscible alloy. As ultrasound power increases, the macrosegregation induced by liquid demixing is strikingly reduced. Meanwhile, a large number of spherical ternary (Al+Sn+θ(Al2Cu)) monotectic cells are formed within ultrasonic field. Cavitation effect, which produces strong shockwaves and facilities the radial symmetry of temperature, concentration, and flow fields in front of liquid–solid interface accounts for these microstructure variations.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slide