| Particulate reinforced aluminium metal matrix composites (Al-MMCs) have many excellent properties such as high specific strength and specific stiffness, resistant wear, steady dimensions. They will increasingly be used in many fields such as aeronautics and astronautics, automobile and electron, which becomes one of the main topics of research and development in the field of metal matrix composites. However, the distinct difference on the parameters of thermal physical and chemical properties between reinforcement and matrix leads to poor weldability of Al-MMCs, which strictly limited its engineering appliance.The bonding technology and mechanism during vibration brazing of SiCp/ZL101A composites were investigated. Mechanical properties of joints brazed by vibration brazing were measured by tensile test, and the microstructure and interface behavior of joints brazed were observed by scanning electron microscope (SEM), energy dispersive X-ray spectrometer, atomic force microcopy (AFM) and X-ray diffraction (XRD) analysis.Two kinds of vibration brazing technology were developed in the paper: contact vibration brazing and non-contact vibration brazing.Results show that contact vibration brazing has some advantages such as simple brazing operation, low brazing temperature, low welding deformation and more effective elimination of the oxidization films on the surface of base materials. It has been found that the oxide film could be broken down by friction and impact between ridges on the surface during contact vibration brazing. However, the pores in bonded joints formed by over-extrusion of the filler metal, which limited further increasing of strength of bonded joints.On the base of the contact vibration brazing, a novel technology of non-contact vibration brazing was developed. The results show that long-time keeping of filler metal in the joint clearance is a key to successfully performing non-contact vibration brazing of AlMMCs. And the semi-solid filler metal obtained by liquation of low-melting phase during bonding not only helps to be kept in joints, but also helps to disrupting of oxide film on the surface.On the theory of compress deformation of semi-solid alloy, a removing model of oxide film during non-contact vibration brazing for AlMMCs was established. At early stage, the disruption of oxide film on the substrate is accomplished by impact of solid grain in the filler metal on the surface of the matrix. On the intermediate and final stage, the oxide film stripped away from the substrate by flushing of the filler metal on the surface of aluminum matrix.The results of twice heating show that the diffusibility of element and dissolution of the base metal were enhanced by elevating temperature and degrading heating rate. Moreover, crystal phenomenon was found in bond zone during heating by heating rate of 1K/s. As element diffusion in bond zone is promoted by increasing of diffusion time at lower heating rate, zinc concentration of joints is distinctly reduced. When the reducing amplitude on zinc concentration in the bond zone caused by increasing temperature with finite heating rate is more than descended amplitude of liquidus concentration with elevated temperature, some crystal starts to generate at heating process. So, the mushy bond zone can be obtained by heating to 520℃with 1K/s. And, zinc diffusion model and solid/liquid interface movement model were established on base of experiments.The results show that gas porosities in joints were extruded out by the second vibration after twice heating. Under vibration pressing, there is separation of solid and liquid in semi-solid joint. And, liquid congregated around gas porosities. Subsequently, gas porosities generate lateral movement the edge of joints. The shear strength of bonded joints increases with time, the maximum strength of joints was obtained at 24s. The fining of eutectic grain and solid reinforcement of elements are one reason of the increase of strength of joints.
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