Research On Purification Of Aluminum Melt By Ultrasonic Treatment

Obtaining high-purity melt is always a focus point and difficult point because the purity of the melt has a significant effect on the performance and product strength, toughness, corrosion resistance and appearance quality of ingot. The purification of melt is based on physical chemistry principles and appropriate technical measures, and aims to remove the gas, impurity and harmful elements in the liquid metal. In this study, high intensity ultrasonic field was introduced in the purification process of melt and the effects on the migration behavior of nonmetallic inclusions were explored under ultrasonic treatment.The hypereutectic Al-20(wt) % Si alloy was used as experimental material and primary silicon particles present in liquid us/solidus reign were used to simulate nonmetal inclusions. The effects of ultrasonic power, ultrasonic treatment time, and the immersion depth of ultrasonic probe and the temperature of melt on the distribution characteristic of primary silicon phase were studied.The following results are obtained:(1) The primary silicon particles move to the edge under ultrasonic treatment, no matter what the temperature is constant temperature or in a certain temperature range (700-630℃);(2) The ultrasonic probe immersion depth has a little effect on the distribution of primary silicon particles;(3) At a constant treatment temperature (630℃), the segregation of primary silicon becomes more significant with the increase of ultrasonic power at the same ultrasonic treatment time and with the increase of ultrasonic treatment time at the same ultrasonic power;(4) When the ultrasonic power, treatment time, and probe insertion depth are the same, the segregation of primary silicon treated in the temperature range 630-700℃is more significant than that treated at constant temperature of 630℃.