| High strength and high conductivity Al2O3/Cu composites has considerable market potential for its excellent properties. At present, the majority of the fabrication methods of this composite are internal oxidation and power metallurgy which have some drawbacks such as complicated fabrication, high cost and so on. In this thesis, as a new method of fabrication metal composites, directed reaction of molten metal (casting process) makes the particles-reinforced phase, the product of chemical reaction in the metal or alloy, be distributed homogenously in the matrix.In this paper, theoretical analyses on fabrication of Al2O3/Cu composites by directed reaction of molten metal has been carried out according to the thermodynamics and kinetics of CuO/Al system, Al2O3 nucleating, solidification and pushing . The chemical reaction control of CuO-Al system has been studied. The results show that the chemical reaction is more stable when cupric oxide and aluminium is put respectively into molten copper.Process parameters controlling Al2O3 particles number size and distribute has been studied. The optimum holding time of this technique is 45min-60min. The poor wettability between Al2O3 and Cu matrix has been overcome. Al2O3/Cu composites have been fabricated. Al2O3 particles are fine (0.5-1 urn) and distribute homogenously in the Cu matrix. The Al2O3/Cu composites interface coheres perfectly, with no pore. The property tests indicate that the hardness and strength of the composite increases with the increasing of Al2O3 percentage; softening temperature is up to 673K ; electric conductivity is more than 80%IACS; Al2O3 content in the composites should be below 1.8wt% when the composites are used in high-strength and high-conductivity field.
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