Formation of Hybrid Metal Matrix Composites by Melt Stirring with Ultrasonic Vibration Based on Interfacial Control

本研究旨在考察超声辅助加热反应和改善润湿性对Al_2O_3颗粒在熔体搅拌过程中融入铝合金熔体的影响。将含有预混镍粉的Al_2O_3颗粒加入到熔化的Al-5质量%镁合金中，在氮气气氛中以16.7 RPS的转速搅拌。然后将超声波传输到带有陶瓷板的铝合金熔体中。将超声波振动应用于熔体搅拌，不仅改善了镍粉的表观润湿性，而且使镍粉完全溶解在铝合金熔体中。利用超声振动促进了镍铝化物生成的放热反应。这种放热反应导致铝合金熔体局部温升，从而改善了铝合金的润湿性。超声辅助铝化镍生成的放热反应有助于提高Al_2O_3颗粒的包覆量，有利于制备无孔复合浆料。

This study is aimed at examining the influence of ultrasound-assisted expthermic reaction and improved wettability on the incorporation of Al_2O_3 particles into molten aluminum alloy in melt stirring. The Al_2O_3 particles with premixed nickel powder were added on molten Al-5 mass %Mg alloy and stirred at a rotation speed of 16.7 rps at 1023 K in a nitrogen atmosphere. The ultrasound was then transmitted to molten aluminum alloy with a ceramic plate. The application of ultrasonic vibration to melt stirring not only improve the apparent wettability, but also the nickel powder to dissolve thoroughly into molten aluminum alloy. The exothermic reaction of nickel aluminide formation is promoted by applying ultrasonic vibration. This exothermic reaction leads to a local temperature rise of molten aluminum alloy, which also improve the wettability. The ultrasound-assisted exothermic reaction of nickel aluminide formation contributes to an increase in engulfed Al_2O_3 particles and also the preparation of pore-free composite slurry.