| Increase the wettability between molten metal and particles and making the particles have a equable dislocation is the key to prepare Metal-matrix composites. The pretreatment of SiC particles and technology of preparing composite slurry by electromagnetic stirring method were researched in aim of improving the wettability between reinforcement and matrix.The experimental result of oxidation treatment of SiC particles showed that the surface impurities were nanometer SiC particles and discontinuous SiO2 film. The sharp angles and nanometer SiC particles on surface were the place where the oxidation began. The surface impurities were engulfed by oxide film as the oxidation goes on. So the oxidation treatment also has the function to enhance wettability by supplying a cleaner surface. The increase rate of the thickness of SiO2 became less when oxidation was goes on, and 6 hours later, it became smooth.The experimental result of electroless plating treatment showed that the SiC's chemical properties are stable, roughing agent of electroless plating could not make particle surface coarser. The traditional electroless plating method could produce a even and compact coating when the load was 20dm2/l.Author proposed a new method to coat SiC particles by Cu. The technique is characterized with shortened proceeding, higher ratio of out put and lower cost. The load can increase to 200dm2/l by using this new method. Although the coating was not as compact as traditional method, but it can also being an pretreatment option to increase the wettability between the particles and slurry.The investment of compound technology showed that: SiC particles coating with Cu, adding SiC particles from middle, placing draining blade and setting the magnetic field frequency at 6Hz not only could improve the wettability between SiC particles and molten matrix but also could make SiC particles distribute homogeneously.
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