超声场作用下Mg-4Al-1Si合金凝固组织

Solidification Structures of Mg-4Al-1Si Magnesium Alloy Treated by Ultrasonic Field

摘要:

采用自行研制的镁合金熔体超声处理装置对Mg-4Al-1Si合金熔体进行处理，研究超声处理功率、超声处理时间和超声处理温度对其凝固组织及相形貌的影响。结果表明：超声处理可以显著细化Mg-4Al-1Si合金的凝固组织，适当提高超声功率和处理温度以及适当延长处理时间均可增强细化效果。650 ℃Mg-4Al-1Si合金熔体经270 W超声处理50 s可以取得较好的细化效果，平均晶粒尺寸为107 μm，为未经超声处理合金晶粒尺寸 (383 μm) 的28%。另外，经超声处理的Mg-4Al-1Si合金中Mg2Si相由未经超声处理时的粗大汉字状转变为细小、弥散分布的颗粒状

Abstract:

Mg-4Al-1Si magnesium alloy melt was treated by self-designed ultrasonic treatment equipment for magnesium alloy melt. The effects of ultrasonic power, treating time and treating temperature on solidification structures of Mg-4Al-1Si magnesium alloy were investigated. The results show that ultrasonic treatment can markedly refine the grain size of Mg-4Al-1Si magnesium alloy, and the grain size is improved by enhancing ultrasonic power, elevating treating temperature, or prolonging treating time. The grain size of Mg-4Al-1Si magnesium alloy treated by 270 W ultrasonic power for 50 s at 650 °C is very fine, 107 μm, which is only 28% as that without ultrasonic treatment (383μm). In addition, the morphology of Mg2Si in Mg-4Al-1Si alloy with ultrasonic treatment changes from coarse Chinese character shape without ultrasonic treatment into tiny granulation with evenly distribution in the matrix.