Preparation method of high anti-corrosion chemical nickel-plating layer

Abstract

The invention provides a preparation method of a high anti-corrosion chemical nickel-plating layer. The preparation method of the high anti-corrosion chemical nickel-plating layer comprises the following steps that a, pretreatment is carried out, specifically, base materials are sequentially subjected to chemical degreasing, electrolytic degreasing and acid pickling, and surface oil contaminationand rust are thoroughly removed; b, bottom layer chemical nickel-plating (medium phosphorous) is carried out, specifically, a layer of medium phosphorous chemical nickel-plating layer with the phosphorous content of 6%-9% is rapidly plated at a plating speed not lower than 12[mu]m / h, the thickness of the medium phosphorous chemical nickel-plating layer is determined according to the base layer surface roughness, and it is ensured that the plating layer has no holes fundamentally; c, surface layer chemical nickel-plating (high phosphorous) is carried out, specifically, a high phosphorous chemical nickel-plating layer with the phosphorous content of 9%-12% is plated again on the medium phosphorous plating layer; and d, post plating thermal treatment is carried out. According to the preparation method of the high anti-corrosion chemical nickel-plating layer, the anti-corrosion performance of the chemical nickel-plating layer can be greatly improved, the thickness 30-50c / o of the plating layer further can be improved on the premise of keeping the same anti-corrosion performance of the plating layer, the production efficiency is improved by two times, and the manufacturing cost is greatly reduced.

Description

technical field [0001] The invention belongs to the technical field of metal and non-metal surface treatment, and in particular relates to a preparation method of a highly corrosion-resistant chemical nickel plating layer. Background technique [0002] Electroless nickel plating is an important surface treatment technology. It has the characteristics of uniform coating, high bonding force, bright and beautiful appearance. It can make materials have excellent corrosion resistance, wear resistance and weldability, and can also metallize non-metallic materials. Therefore, it is widely used in aerospace, petrochemical, automobile and ship, electronic communication, medical facilities, electromagnetic protection and other fields. [0003] The electroless nickel plating layer is a cathodic plating layer. Once there are small holes or damages on the surface that reach the base material, the nickel plating layer will corrode rapidly. Therefore, the corrosion resistance of the elect...

AI Technical Summary

Problems solved by technology

[0004] Due to the characteristics of self-catalytic reaction of electroless nickel plating, when nickel is deposited on the workpiece, it will also be deposited on the tank wall and related pipelines, reducing the utilization rate of nickel; at the same time, if the deposits on the tank walls and pipelines are not cleaned in time, it will Cause quality problems such as rough coating and low corrosion resistance

Therefore, in the production of electroless nickel plating, it is necessary to frequently replace the plating tank and clean the tank wall and pipeline, resulting in low production efficiency and difficult production and maintenance

On the other hand, during the electroless nickel plating reaction process, the by-product phosphite, impurity ions and K + 、Na + , NH 4 + , SO 4 2- The waiting solution will accumulate with the prolongation of the service life, which will easily cause the aging and failure of the plating solution, and finally the plating solution has to be discarded

It can be seen that to prepare a single 50 μm electroless nickel layer, the plating time needs to be 5-8 hours, and the temperature of the plating solution must be kept above 85°C. Not only the production efficiency is low, but also the energy consumption is high, and the consumption of the plating solution is large. high cost