Effects of cooling conditions on the microstructure of semisolid AZ91 slurry produced via ultrasonic vibration process
Effects of cooling conditions on the microstructure of semisolid AZ91 slurry produced via ultrasonic vibration process were investigated.AZ91 melts were subjected to ultrasonic vibration in different temperature range under different cooling rate.The results showed that fine and spherical α-Mg particles were obtained under ultrasonic vibration during the nucleation stage,which was mainly attributed to the cavitation and acoustic streaming induced by the ultrasonic vibration.The reduction of lower limit of ultrasonic vibration temperature between the liquidus and solidus increased the solid volume fraction and average particle size.Increasing cooling rate increased the solid volume fraction and reduced the average shape factor of particles.In this study,the appropriate temprature range and cooling rate for ultrasonic vibration process were from 605 ℃ to 595 or 590 ℃ and between 2 ℃/min to 3 ℃/min,respectively.
Semisolid AZ91 alloy ultrasonic vibration microstructure cooling condition
Zhang Liang Wu Guohua Wang Shaohua Ding Wenjiang
National Engineering Research Center of Light Alloys Net Forming, Shanghai Jiao Tong University, 800 Beijing Institute of Nearspace Vehicles Systems Engineering, Beijing 100076, PR China
国际会议
上海
英文
261-261
2012-10-19（万方平台首次上网日期，不代表论文的发表时间）