Papers by Keyword: Ultrasonic Stirring

Abstract: Two samples of ZnO doped Ba with the chemical composition, 97ZnO-3BaO, have been prepared via oxalate co-precipitation. During precipitation the first sample, A, was stirred by magnetic stirrer while the second sample, B, was stirred via 40KHz ultrasonic wave. The obtained powders were decomposed at 400°C for 3h, then pressed and sintered at 1200°C for 1.5h. Then XRD, SEM and J-E measurements were performed and analysed. The grain sizes of the obtained ceramics were (0.5-2.26) µm and (80-119) nm for samples A and B, respectively. The J-E measurements revealed that the obtained ceramic has voltage switching characteristics, and that the switching voltage could be controlled by the stirring process.

Abstract: The perfect semi-solid magnesium alloy had been prepared using ultrasonic stirring method. The effect of technological parameters such as melt temperature, ultrasonic power and ultrasonic treatment time on the microstructure of semi-solid AZ61 alloy had been investigated. The results showed that the better refined and well-distributed globular semi-solid magnesium alloy had been acquired with the increasing of output power of ultrasonic stirring when melt temperature and ultrasonic treatment time were at a certain range.