超声处理对SiC颗粒增强铝基复合材料微结构与性能的影响

Effect of Ultrasonic Treatment on Microstructure and Property of SiC Particles Reinforced Aluminum Matrix Composites

利用超声波预处理颗粒与合金熔体的复合工艺制备SiC颗粒增强铝基复合材料,研究七种不同的超声预处理工艺对SiC颗粒表面清洁度与润湿性的影响规律,研究搅拌过程中不同超声功率、施振时间对增强体颗粒分布、界面形态与材料原生性能的影响规律及作用机制。结果表明:高温焙烧工艺可以显著改善颗粒的清洁度与润湿性;增大超声功率能够增强对SiC颗粒团聚的抑制作用,提高其在基体组织分布的均匀性,在功率一定的条件下,施振时间不宜过长,否则超声的驻波效应将形成颗粒的二次偏聚。

SiC particles reinforced aluminum matrix composites were prepared through processing particles and alloy melt by ultrasonic. The effect of seven kinds of ultrasonic pretreatment processes on cleanliness and wettability of SiC particle surface was studied. Meanwhile, the effect and action mechanism of ultrasonic power and vibration time on reinforced particle distribution, interface morphology and primary properties of materials were studied. The results show that the cleanliness and wettability of the SiC particle can be greatly improved by the high temperature roasting process. Increasing the ultrasonic power can enhance the inhibition of particle agglomeration and improve its uniformity of the distribution in the matrix. The appropriate prolongation of ultrasonic vibration time can also reduce the agglomeration of particles. However, the ultrasonic vibration time should not be too long;otherwise the second segregation of SiC particles will be formed due to the effect of the ultrasonic standing wave.