Effect of synergistic action of ultrasonic vibration and solidifi cation pressure on tensile properties of vacuum counter-pressure casting aluminum alloy

Abstract

The effect of synergistic action of ultrasonic vibration and solidifi cation pressure on tensile properties of vacuum counter-pressure casting ZL114A alloys was studied systemically through testing and analyzing the tensile strength and elongation subjected to different ultrasonic powers and solidifi cation pressures. The results indicate that the synergistic action of ultrasonic vibration and solidifi cation pressure can result in the refi nement of grains and improvement of tensile properties. Both the highest tensile strength and elongation of aluminum alloy were obtained under synergistic action of 600 W ultrasonic power and 350 kPa solidifi cation pressure. Moreover, the tensile fracture morphology shows obvious ductile fracture characteristics. When the solidifi cation pressure is lower than 300 kPa, the effect of ultrasonic power on tensile strength and elongation is more obvious, but when the solidifi cation pressure is higher than 300 kPa, the effect of solidifi cation pressure on tensile strength and elongation is greater. Meanwhile, the size and morphology of the eutectic silicon were improved signifi cantly by the ultrasonic vibration and pressurized solidifi cation. The strip and massive eutectic silicon phase are completely converted into small short rod-like and evenly distributed Si phases at the grain boundary of primary α-Al.

Keywords

• ultrasonic power; solidification pressure
• vacuum counter-pressure casting
• aluminum alloy