A kind of preparation method of silver-plated copper powder

Abstract

The invention relates to a preparation method of silver-plated copper powder, and belongs to the technical field of surface treatment. According to the preparation method of the silver-plated copper powder, copper power is soaked and washed in sodium hydroxide solution, then the copper power is put in diluted acid solution and is soaked and washed directly after being filtered, and at last the copper powder is flushed with distilled water after being filtered. Under the condition that the copper powder is stirred, complexion agents, dispersing agents and silver nitrate solution are added sequentially in the copper powder washed with the distilled water, the motion of stirring is stopped, the copper powder is filtered and washed until no copper ion exists in cleansing solution, the washed copper powder is dried, and the silver-plated copper powder is obtained. The resistance rate of the silver-plated copper powder prepared through the preparation method can reach 4.6*10-6 omega per meter, the oxidation resistance performance of the silver-plated copper powder is improved obviously, initial oxidizing temperature can reach above 350 DGR C, the phenomenon that the copper powder is oxidized easily is avoided effectively, and the silver-plated copper powder can be widely applied to the field of high-conductivity and heat-resisting materials, such as conducting resin, conducting coating and electromagnetic shielding.

Description

technical field [0001] The invention relates to a preparation method of silver-plated copper powder, which belongs to the technical field of surface treatment. Background technique [0002] With the development of the electronics industry, the application range of metal powder materials has been broadened. Many metal powders have become important materials for electronic components. Silver powder is widely used in conductive coatings, conductive adhesives, and electromagnetic shielding materials because of its good conductivity. , but silver is expensive and the conductive composite material prepared with silver powder as a conductive filler is prone to silver migration under the action of DC voltage; copper is low in price and its performance is second only to silver, and it is a good substitute for silver in terms of performance. However, copper is easily oxidized to form an insulating oxide film, which reduces stability and reliability. Micron-sized copper powder has str...

AI Technical Summary

Problems solved by technology

However, whether the rare earth elements contained in the silver-plated copper powder will affect the performance of the silver-plated copper powder during use remains to be discussed.

Invention patent application (CN101774025A) discloses a preparation method of silver-plated copper powder, using ethylenediaminetetraacetic acid sodium salt as a complexing agent to prepare silver-plated copper powder by displacement plating, but does not mention silver-plated copper powder High temperature oxidation resistance; Invention patent application (CN1876282A) discloses a preparation method of silver-plated copper powder, which is based on the basic principle of silver mirror reaction, using glucose as a reducing agent to prepare silver-plated copper powder through silver ammonia solution, The composition of the plating solution is relatively complicated and the cost is high, and none of the above inventions mentions the high temperature oxidation resistance of the silver-plated copper powder

Invention patent (200810058362.0) discloses a preparation method of silver-plated copper powder for low-temperature slurry, but the products prepared are limited to use in the field of low-temperature slurry

The literature [Study on the reaction process of silver-coated ultra-fine copper powder prepared by electroless plating] (Journal of Wuhan University of Technology, 2008, 30 (1): 24-27) introduced the addition of strong reducing agent hydrazine hydrate to make the silver ammonia solution preferentially generate liquid Phase reduction reaction, after three coatings, a continuous silver film is formed on the surface of copper powder. Due to the toxicity of hydrazine hydrate, it is difficult to expand this process, and it does not meet the requirements of environmental protection.

Images