Effect of Ultrasound on Solute Dispersion of Immiscible Al-Pb Alloy

摘要

The effects of ultrasonic power, duration and the content of Pb on solute dispersion of Al-Pb alloy werernstudied. Lead dispersion was observed by BSE (Back Scattered Electron) and hardness and wear-resisting properties werernmeasured. The results indicate that ultrasonic power and duration equally have a direct effect on Pb solute dispersion. Thernhigher or smaller power and longer or shorter ultrasonic duration will not reach satisfied dispersion effect. When power isrn1125W or ultrasonic duration is 120s, the optimum dispersion effect will be reached. When solute content is very high, thernbetter dispersion effect will not be reached. When Pb solute is distributed finely and homogeneously in the matrix, thernhardness and wear-resisting property of Al-Pb alloy will increase. When ultrasonic field disperses Pb particles, the particlesrnwill have the tendency of spontaneous aggregation, which can reduce surface energy. With the change of ultrasonic power,rnduration and solute content, the effect of dispersion does not increase or reduce monotonously. The whole ultrasonicrntreatment is an integrated process of aggregation and dispersion. When the condition is proper, there will have an optimumrndispersion effect.