CN100532655C - The Method of Re-plating Nickel on Metal Plating Parts - Google Patents

Abstract

The invention discloses a method to complement nickel-plating of metal plating component. It includes the following steps: cleaning the surface of metal plating component by common method; using HCL 250-400 g/L as electrical acid active electrical acid solution, impressing anode current at 2-4 A per square decimeter on the component, adopting nickel board as cathode and lasting for 1-3 minutes; using common method to complement nickel, cleaning, activating and plating chrome. The invention could make the component has good binding power, and it is simple technology.

Description

The Method of Re-plating Nickel on Metal Plating Parts

technical field

The invention belongs to the field of surface treatment of metal materials, and in particular relates to a nickel replating method for a metal plating piece with good bonding force after replating and simple operation.

Background technique

In the process of industrial production, it is often necessary to electroplate the surface of parts to improve the anti-corrosion performance and decoration of the surface. In the process of decorative chrome plating, due to some uncontrollable factors sometimes, the coating is partially incomplete or faded. When this happens, the unqualified coating does not need to be removed and re-plated, but only needs to be re-plated, that is, it will be removed. A thin decorative chromium layer (only 0.25-0.5 microns) and a part of the nickel layer are added to the thickness of the nickel layer, and then the decorative chromium layer is electroplated. At present, the process flow of replating is: anode degreasing→cathode degreasing→cleaning→cleaning→acid activation→replating bright nickel→cleaning→cleaning→sulfuric acid activation→bright chrome plating. This process is not only more complicated to operate, but also takes a long time to work in the whole process, and the bonding force of the coating after repairing is not good. Some of them showed up at the time, and some showed up after delivery, leaving a very bad impression on users.

Contents of the invention

The purpose of the present invention is to provide a method for re-plating nickel on metal plated parts. It makes the bonding force of the plating layer and the workpiece good after replating, and the process is simple, and the product surface quality is good.

The purpose of the present invention is achieved like this:

The present invention comprises the following steps

(1) Use conventional methods to degrease and clean the surface of the metal plated parts;

(2) Electrolytic acid activation

Hydrochloric acid solution is HCl 250～400 g/L

Apply an anode current of 2 to 4 amps/square decimeter to the metal plated parts, and use a nickel plate for the cathode, time: 1 to 3 minutes;

(3) Nickel supplementation, cleaning, activation and chrome plating are performed by conventional methods.

The advantages of the present invention are:

1. Electrolytic acid activation is used to complete the two-step process of removing the chromium layer, part of the bright nickel layer and pre-plating activation in one step, so the process can be simplified and the operation is simple;

2. Because nickel is not very active, it reacts slowly with hydrochloric acid and sulfuric acid. Only by electrolytic acid activation can nickel be activated and the nickel lattice be opened, so that the bright nickel layer after replating can be well combined with the nickel layer that has opened the lattice. Therefore, the bonding force of the coating is guaranteed.

Below in conjunction with embodiment the present invention will be further described.

Detailed ways

Example 1

Use the conventional method to degrease and clean the surface of the metal plated parts, according to the hydrochloric acid: 300 g/liter, use the nickel cathode plate, activate the electrolytic acid with the anode current of 2 amps/square decimeter for 3 minutes, and then use the conventional method The method is to re-plate bright nickel, wash twice, activate sulfuric acid, plate bright chrome, and re-plate 10 shift pedals. After plating, the binding force of the coating was measured by the file method, and the test result was qualified.

Example 2

Use conventional methods to degrease and clean the surface of metal plated parts. According to hydrochloric acid: 300 g/liter, use nickel cathode plate, activate electrolytic acid with an anode current of 2.5 amps/square decimeter for 2.5 minutes, and then use conventional The method is to re-plate bright nickel, wash twice, activate sulfuric acid, plate bright chrome, and re-plate 10 shift pedals. After plating, the binding force of the coating was measured by the file method, and the test result was qualified.

Example 3

Use the conventional method to degrease and clean the surface of the metal plated parts. According to hydrochloric acid: 330 g/liter, use nickel cathode plate, activate the electrolytic acid with an anode current of 3 amps/square decimeter for 2 minutes, and then use conventional The method is to re-plate bright nickel, wash twice, activate sulfuric acid, plate bright chrome, and re-plate 10 pieces of shock-absorbing springs. After plating, the binding force of the coating was measured by the file method, and the test result was qualified.

Example 4

Use the conventional method to degrease and clean the surface of the metal plated parts, according to the hydrochloric acid: 370 g/liter, use the nickel cathode plate, activate the electrolytic acid with the anode current of 3.5 amps/square decimeter for 1.5 minutes, and then use the conventional The method is to re-plate bright nickel, wash twice, activate sulfuric acid, plate bright chrome, and re-plate 10 pieces of shock-absorbing springs. After plating, the binding force of the coating was measured by the file method, and the test result was qualified.

Example 5

Use the conventional method to degrease and clean the surface of the metal plated parts. According to the hydrochloric acid: 400 g/liter, use the nickel cathode plate, activate the electrolytic acid with the anode current of 4 amps/square decimeter for 1 minute, and then use the conventional method. The method is to re-plate bright nickel, wash twice, activate sulfuric acid, plate bright chrome, and re-plate 10 shock-absorbing sleeves. After plating, the binding force of the coating was measured by the file method, and the test result was qualified.

When the present invention degreases the surface of the metal plated parts, the combination of the anode and cathode of the part is used for better degreasing effect.

Claims (1)

1. A kind of method of repair nickel coating no metal coated piece is characterized in that: may further comprise the steps

   (1) adopt conventional method that metal plating piece surface is cleaned;

   (2) electrolysis acid activation

   Hydrochloric acid soln is HCl 250～400 grams per liters

   The metal plating piece imposes the anodic current of 2～4 peace/square decimeters, negative electrode nickel plate, time: 1～3 minute;

   (3) mend nickel, cleaning, activation and chromium plating with conventional method.