Non-cyanide copper-tin alloy plating solution

Abstract

The invention provides a non-cyanide copper-tin alloy plating solution, wherein the copper-tin alloy plating solution comprises the following main components: stannous pyrophosphate and copper pyrophosphate, potassium pyrophosphate or sodium pyrophosphate as main complexing agent, succimide as auxiliary complexing agent, and soluble dihydric phosphate as buffering agent. The operating conditions of the non-cyanide plating solution are as follows: the pH range is 7.0-9.5; the current density is 0.3-2.5 A / dm2; and the temperature is 20-40 DEG C. The non-cyanide copper-tin alloy plating solutionhas the advantages of being low in cost, simple and convenient for operation and maintenance, and having little toxicity or no toxicity, wide density range of cathode current, high current efficiency, fine and bright plating; and the non-cyanide copper-tin alloy plating solution can satisfy the application requirements in multiple fields such as decoration plating, functional plating and the like.

Description

Technical field [0001] The invention relates to a cyanide-free copper-tin alloy electroplating solution. Background technique [0002] With the continuous development of science and technology, the requirements for products are becoming more and more stringent. It is difficult for a single element coating to meet the needs of electroplating products. Researchers gradually turn their attention to alloy electroplating. In alloy electroplating, copper-tin alloy coating has excellent corrosion resistance and oxidation resistance, and can be widely used in decorative coatings such as silver replacement. At the same time, copper-tin alloy can effectively prevent the diffusion of base metal atoms into the coating The surface, so as to avoid causing discoloration, is used to replace the nickel layer (direct contact with metallic nickel can cause nickel sensitivity to the human skin). So far, cyanide plating is mainly used for copper-tin alloy plating at home and abroad. This is because ...

AI Technical Summary

Problems solved by technology

[0004] Compared with cyanide plating solutions, these cyanide-free copper-tin alloy plating solutions have the following disadvantages: (1) low current density (0.5 A / dm 2 ~ 1.0A / dm 2 ); (2) The plating solution is unstable; this is because Sn (II) is easily oxidized, and Sn (IV) is easily hydrolyzed to form insoluble acid-base β-stannate; (3) The cost is relatively high; this is due to many cyanide-free Copper-tin alloy electroplating solution configuration method is complicated, and more complexing agents or auxiliary complexing agents are used, resulting in complicated solution components