The Processing And Experimental Study Of Ultrasonic Assistant Preparation SiC_p/7050Composite

This thesis focuses on ultrasonic method in the preparation of SiC aluminum base composite material, the application of SiC particles using ultrasonic washing after high temperature roasting and with measures of liquid aluminum heat preservation, it improves the wettability between SiC and aluminum alloy melt. Then, By mechanical stirring disperses SiC particles into the alloy melt, then through the ultrasonic processing improve wettability between SiC particles and aluminum alloy melt further, it improves the structure and performance of composite materials, we can obtain, fine SiCp/7050composite materials.Test and research of pretreatment technology to SiC particles, we could reach a good pretreatment process:SiC particles obtained by high temperature roasting oxidation in1000℃after ultrasonic cleaning process, then it was heated preservation with the aluminum alloy. Application of compocasting process, the SiC particles after treatment by this technology would spread to7050aluminum alloy melt easily. After compared and analyzed the experimental results, we could get the effect on SiC particle surface physical and chemical adsorption gas by this good pretreatment process, the ultrasonic cleaning could clean off the surface oil pollution and part of the physical adsorption and chemical adsorption of fine powder, high temperature roasting oxidation could clear the remaining Si4+and oil pollution after ultrasonic cleaning, the process heat preservation with the aluminum alloy could avoid moisture and dust in the air adhesion to SiC particle surface again.Using the SiC of the best pretreatment, we disperse them into the alloy melt by mechanical stirring and get composite of SiC particles evenly distributed. But after mechanical agitation process, there are lots of pore and porosity in the microstructure of composite. So use ultrasonic vibration process after mechanical stirring, we get composite materials with SiC particles dispersed evenly and have no defect, then testing its performance, its wear ability, hardness, tensile properties were increased. Finally analyze the principle of ultrasonic process, comparison the effect of ultrasonic cavitation with ultra sound flow in different locations; we concluded that in the process of ultrasonic degassing process, melt flow decided the ultrasonic degassing result.