Prepn process of composite Cu-Ag metal powder in core-shell structure

Abstract

The present invention relates to preparation process of composite Cu-Ag metal powder in core-shell structure. Cu powder is pre-plated in a direct plating process for Ag to crystallize and grow in the surface of Cu well, and through twice chemical reactions in glucose bath and twice densifying treatments, micron level Cu powder is clad with a complete compact Ag layer with greatly reduced gaps. The Ag plated Cu powder has improved high temperature oxidation resistance in the temperature up to 790 deg.c, and high binding strength between the Cu core and the Ag shell.

Description

technical field

[0001] The invention relates to a preparation process of conductive metal powder, in particular to a preparation process of Cu-Ag composite metal powder. Background technique

[0002] Silver has the best electrical conductivity among all metals, and its room temperature (20°C) resistivity ρ=1.59×10 -6 Ω.cm, in addition, Ag also has the characteristics of good oxidation resistance and stable performance. However, it is expensive and resources are scarce, so it can only be used in special occasions and cannot be applied on a large scale. The price of Cu powder is low, only about 1 / 20 of Ag, and its conductivity is excellent (ρ=1.7×10 -6 Ω.cm), are widely used in conductive coatings, electrode materials, catalysts and other fields. However, Cu has poor oxidation resistance, and it is easy to form an oxide film on the surface exposed to the air for a long time, which has a great impact on its performance. Plating silver on the surface of copper powder can ove...

Images