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Magnesium alloy has many unique advantages, so it draws inceasingly a wider range of attention, but its shortcomings of low surface hardness, low corrosion resistance limit the scope of its application. Nickel coating is an effective method of protection. Electrodeposition plating has fast the advantages of high deposition rate, smooth surface, and low costs. In this thesis, first, pre-eletroless Ni/P planting on magnesium alloy, next in the electro-deposition process of nickel plating that i adding nano-TiO2 particles in the solution, the solution scattered with mechanical agitation, ultrasonic dispersion and adding surfactants to make better nanoparticles the codeposition formed on the surface of magnesium alloy in the nano-composite coating. Through the process of electrodeposition that change pH value, electroplating solution temperature, the amount of nano-particles and plating time, that analysis the relationship between hardness, nanocomposite coatings, corrosion resistance and the bonding matrix for a systematic. Obtained nanocomposite electrodeposition coatings rate is one times than electroless plating, look at micromorphology that the surface of nano-composite coating grow well, dense, uniform thickness, through the bending test and thermal shock test proved nano-magnesium alloy matrix composite coating have a good combination. Electrodeposited coatings deposited nano-TiO2 particles, the micro-hardness of composite coating has greater improvement, indicate that the addition of nano-particles has a strengthening effect on the composite coating. For immersion tests and the polarization curve of the experimental test, nano-composite coating can increase the magnesium alloy corrosion resistance.
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