Cyanide-free alkaline copper electroplating solution and electroplating technology

Abstract

The invention discloses a cyanide-free alkaline copper electroplating solution and an electroplating technology and belongs to an environment-friendly high-performance copper electroplating technology. The technological process is as follows: fine polishing and grinding, chemical degreasing, electrolytic degreasing, pickling and activation as well as electroplating. On the premise that the good binding force between plating and a matrix is guaranteed, the covering power and the throwing power of the copper plating obtained through electroplating with the technology are superior to those of copper plating obtained through electroplating with a cyanide copper electroplating technology, the porosity and the toughness of the plating can reach the level of the cyanide copper electroplating technology, and the electroplating solution and the electroplating technology are suitable for direct copper electroplating of aluminium alloy and zinc alloy die-casting matrixes as well as copper electroplating of steel and copper matrixes. Meanwhile, the copper electroplating solution is good in stability and high in current efficiency, wastewater treatment is simple, and the plating is uniform, compact, soft and shining, has no hydrophobicity, requires no film removal and can be directly used for subsequent electroplating of other metals.

Description

technical field [0001] The invention belongs to the technical field of electrochemical copper plating, in particular to a cyanide-free alkaline copper plating electroplating solution and an electroplating process. Background technique [0002] Copper is a soft, plastic, slightly reddish metal with good electrical and thermal conductivity and good ductility. Copper plating is generally used as a decorative intermediate coating to protect base metals such as zinc and iron. There are many copper plating solutions for obtaining copper plating, and the commonly used ones are only cyanide copper solution, acid sulfate copper solution and pyrophosphate copper solution. Iron and steel parts and zinc alloy parts cannot be directly plated with copper in acidic sulfate bath and pyrophosphate bath, because if these parts are directly immersed in these baths, there will be a substitution reaction before the current is turned on, resulting in A layer of loose replacement coating affects ...

AI Technical Summary

Problems solved by technology

However, these processes cannot completely replace the cyanide copper plating process due to their own shortcomings, especially for the problem of direct bottom copper plating on zinc alloy die castings, there is still no better process that can be compared with the cyanide copper plating process. Compare

[0004] The biggest problem to be solved by the cyanide-free copper plating process to replace the cyanide copper plating process is to solve the problem that the matrix metals such as iron and zinc are easily replaced by copper ions in the plating solution, thereby forming a loose replacement layer. The combination with the substrate is not strong, and the purpose of electroplating cannot be achieved

Most of the cyanide-free copper plating processes researched and developed at present have only overcome the replacement phenomenon to a certain extent. There is no good and effective cyanide-free copper plating process for copper plating on zinc alloy die castings.