Ultrasonic assisted squeeze casting of a wrought aluminum alloy

Abstract

In the present work, an ultrasonic assisted squeeze casting method is proposed for processing wrought aluminum alloys. A frame-shaped part was fabricated to verify the feasibility of ultrasonic assisted squeeze casting technology. The results show that a 2024 alloy part with a complex shape and good surface quality can be produced by the proposed ultrasonic assisted squeeze casting method. As the ultrasonic power increasing, the microstructures of the squeeze cast parts were clearly refined, and the coarse polygonal or dendritic structures evolved to fine and equiaxed grains. Mechanical properties, such as strength and plasticity, were also improved significantly as the ultrasonic power increasing. When the ultrasonic power was 1.8 kW, the UTS, YS and elongation to fracture were 372 MPa, 246 MPa and 8.5%, which were improved by 20.8%, 21.2% and 84.8%, respectively, compared to a conventional squeeze cast part. Finally, the effect of ultrasonic vibration on mold-filling and solidification was analyzed.