Preparation and anti-oxidisation resistance of silver-coated copper powders by cobalt-modified copper powders

Spherical copper powders and cobalt-modified copper powders were electroless plated with silver, respectively, to obtain two kinds of silver-plated copper powders. The composite powders were analysed by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy and thermogravimetric-differential scanning calorimetry. Effects of cobalt modification on surface morphology, silver reduction rate, particle size and anti-oxidisation resistance of composite powders were studied. The results indicate that surface morphology of silver-coated copper powders prepared by cobalt-modified copper powders was affected by cobalt, but the size, mass and the percent reduction of silver were significantly increased under the same conditions of electroless plating silver. And silver-coated copper powders prepared by cobalt-modified copper powders have better anti-oxidisation resistance than silver-coated copper powders prepared by copper powders.