A Comparative Study on the Effect of Four-Source Ultrasonic Power on the Microstructure and Mechanical Properties of Large-Scale 2219 Aluminum Ingots

High-intensity ultrasound was introduced into the direct chill casting of large-scale 2219 aluminum alloy ingots (1380 mm in diameter and 4600 mm in length). The effects of four-source ultrasonic irradiation with various powers on the morphologies, size of alpha-Al grains and Al2Cu precipitated phase as well as the mechanical properties of the ingots were compared. The results indicated that, when the total real-time power of the ultrasonic system was maintained at 4030 W, a grain-refined structure with a more uniformly dispersed Al2Cu precipitated phase was obtained in the ingot. The mechanical properties of the ingot cast under a total power of 4030 W was also better than the ingots cast under 3600 W and 4420 W. It was found that the stress concentration caused by large area of coarse Al2Cu phase in the ingots under 3600 W and 4420 W resulted in the deterioration of mechanical properties.