Lead brass silver plating process

Abstract

The invention discloses a lead brass silver plating process which comprises the following steps: chemically deoiling; ultrasonically cleaning; pickling; electrolytically deoiling; galvanizing and stripping; pre-plating silver; and carrying out post-treatment process. In the galvanizing step, a zinc layer wraps and covers slag and dust on the surface of a part in a precipitation process. As zinc and copper have a relatively great potential difference, certain replacement reaction is bound to happen on zinc and copper to generate an intermediate layer mingled with copper and zinc. The intermediate layer enhances the bonding force of the two metals. In the pickling process, severe hydrogen evolution reaction plays a strong impact role on slag and dust, so that the slag and dust are separated from the surface of the part, therefore, a good deslagging and dedusting role is played. In the step of pre-plating silver, an alloy of copper and mercury covers the surface of the copper part through amalgamation first so as to improve bad replacement caused by a relatively great potential difference; and after amalgamation, silver is pre-plated on the surface of the copper part, and the appearance quality of the plate is improved well.

Description

technical field [0001] The invention belongs to the technical field of electroplating, and more specifically relates to a silver plating process for lead brass. Background technique [0002] Lead brass is the most widely used complex brass. It has excellent cutting performance, wear resistance and high strength. It is mainly used in various connectors, valves, valve stem bearings and so on in mechanical engineering. [0003] Lead brass welding parts need to be silver-plated. The quality of the silver-plated layer is directly related to the performance of the welding product, and the performance of the product is related to the performance of the product. Therefore, it is necessary to improve the silver plating quality of the product. In order to ensure the quality of the silver plating layer, a series of processes need to be carried out. However, the traditional silver plating process is used to plate silver on this material, and the adhesion fails many times in the finished...

AI Technical Summary

Problems solved by technology

Therefore, it is necessary to improve the silver plating quality of the product. In order to ensure the quality of the silver plating layer, a series of processes need to be carried out. However, the traditional silver plating process is used to plate silver on this material, and the adhesion fails many times in the finished product, and the silver layer Defects with poor surface compactness (such as figure 1 Shown), there are quality risks, affecting product performance

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