Liu J M, Wu W H, Zhai W, Wei B
Department of Applied Physics, Northwestern Polytechnical University, Xi'an 710072, PR China.
Department of Applied Physics, Northwestern Polytechnical University, Xi'an 710072, PR China.
Ultrason Sonochem. 2019 Jun;54:281-289. doi: 10.1016/j.ultsonch.2019.01.029. Epub 2019 Jan 22.
The effect of power ultrasound on the liquid phase separation of ternary Cu-32%Sn-20%Bi immiscible alloy is experimentally investigated, which shows that as compared with the layered structure formed under static condition, the macrosegregation resulted from liquid phase separation is remarkably reduced with the increase of ultrasonic amplitude. A homogenous microstructure characterized by refined (Bi) particles dispersing uniformly on the (CuSn) matrix is obtained when the ultrasonic amplitude reaches the highest value of 24 μm. This is mainly ascribed to the ultrasonically induced cavitation and acoustic streaming, which promotes the nucleation, the fragmentation, and the dispersion of (Bi) droplets. The finally solidified immiscible alloy exhibits obvious improvements in electrochemical corrosion resistance, microhardness and wear-resisting if compared with those in static solidification. These results prove that applying power ultrasound is an effective way to modulate the liquid phase separation and enhance the applied performance for immiscible alloys.
实验研究了功率超声对三元Cu-32%Sn-20%Bi不混溶合金液相分离的影响，结果表明，与静态条件下形成的层状结构相比，随着超声振幅的增加，液相分离导致的宏观偏析显著降低。当超声振幅达到24μm的最大值时，获得了以均匀分散在（CuSn）基体上的细化（Bi）颗粒为特征的均匀微观结构。这主要归因于超声诱导的空化和声流，其促进了（Bi）液滴的形核、破碎和分散。与静态凝固相比，最终凝固的不混溶合金在耐电化学腐蚀性、显微硬度和耐磨性方面表现出明显的改善。这些结果证明，施加功率超声是调节液相分离和提高不混溶合金应用性能的有效方法。
