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The application of ultra-fine powder, which greatly promoted the new material in the electronic information, aerospace, metallurgy, transportation and other industries. As the powder particle size decreases, surface active particles increases, so prone to agglomeration between particles, to reduce oxidation, leaving the particles lose their identity, loss of application. As nickel Copper metal powder has excellent corrosion resistance and electrical conductivity, while its wear properties and load-carrying capacity can be significantly improved; both nickel powder has good electromagnetic shielding performance, an excellent shielding material as in the military and civil industry has been widely used, but compared to the pure nickel powder, copper high price of poor conductivity, the combination of materials can greatly enhance the cost and applications, so preparation of copper-nickel package has important markets and practical significance. Liquid-phase reduction method copper powder, and on its surface coated by electroless plating method nickel particles, forming ultrafine nickel copper particles. Preparation of Nickel clad copper process technology, were investigated initial solution concentration of copper ion, nickel ion concentration, reductant species, PH value range, copper-nickel mass ratio, mixed mode, ultrasonic power and other process parameters on the copper-nickel package size, coating effects and dispersion were investigated: 1. mixing of raw materials in two ways, one is to pre-reduced copper powder as matrix, and then electroless nickel plating; Second were preparing for the Cu powder and Ni powder and then mixed in water. The results showed that: raw material mixing method for nickel copper clad composite powders and coating microstructure great effect, the nickel copper particles by only Cu, Ni 2 phase composition; 2 prepared in advance of different size Cu powder prepared by electroless plating on nickel-coated copper composite ultrafine powder by scanning electron microscopy, energy dispersive spectroscopy study of nickel-coated copper powder morphology and composition, test exam-ined body Cu powder particle size on the effects of nickel-coated affected. The results showed that: the matrix Cu powder finer granularity of nickel coated better, but will also reduce the dispersion of the powder; 3. Use of ultrasound in the pre-Cu powder prepared by electroless plating on the Preparation of Ultrafine Nickel coated copper composite powders were investigated Cu 2 concentration, Ni 2 concentration, ultrasonic power and other factors on Nickel clad copper powder conversion rate, coating effects and dispersion effects, with SEM , EDS and XRD characterization of nickel-coated copper powder morphology, composition and phase composition. The results showed that: the ultrasonic conditions, to obtain a better dispersion of the nickel-coated copper composite powder in the composite powder Cu, Ni content did not change significantly.
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