1. The solenoid valve coil nickel plating process sequentially comprises the following steps:

a) placing an electromagnetic valve coil in a primary nickel priming solution, wherein the primary nickel priming solution consists of 150g/L of nickel sulfate with the concentration of 100-;

b) and placing the solenoid valve coil after the primary electroplating of the primary nickel priming solution in the secondary priming solution, wherein the secondary priming solution is prepared from organic additives: succinic acid, fatty acids, and thioglycolic acid; inorganic additives: sodium fluoride and water, wherein succinic acid, fatty acid, thioglycollic acid and sodium fluoride are mixed at a ratio of 2:1:1:1, and are stirred for 3-5min at 15-20 ℃, the electroplating time is 10-15min, the anode current is increased, and the deposition of nickel is promoted;

c) placing the solenoid valve coil subjected to secondary nickel electroplating in a tertiary bottoming solution, wherein the tertiary bottoming solution consists of a brightening agent, a softening agent, a wetting agent, an impurity removing agent and water, the ratio of the brightening agent to the softening agent to the wetting agent to the impurity removing agent is 1:1:1:1, stirring for 3-5min in an environment at 20-35 ℃, placing the solenoid valve coil in a plating barrel, and electroplating for 10-15min at a power supply voltage of 5-10V.

Background

The electromagnetic valve is an industrial device controlled by electromagnetism, is an automatic basic element for controlling fluid, belongs to an actuator, and is not limited to hydraulic pressure and pneumatic pressure. The method is used for adjusting the direction, flow, speed and other parameters of a medium in an industrial control system, and a nickel plating treatment needs to be carried out on a surface coil in the winding production process of the electromagnetic valve coil so as to improve corrosion resistance, hardness, weldability and magnetism.

However, in the existing nickel plating process, during the coil galvanization process, the nickel anode is easily passivated, and only oxygen is washed out during electrification, so that the concentration of nickel ions is reduced, the holes of a plating layer are increased, the glossiness is reduced, and the hardness of a nickel plating layer is reduced.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention provides a solenoid valve coil nickel plating process which improves the brightness and hardness.

In order to solve the technical problems, the invention provides the following technical scheme: the solenoid valve coil nickel plating process includes the following steps:

a) placing an electromagnetic valve coil in a primary nickel priming solution, wherein the primary nickel priming solution consists of 150g/L of nickel sulfate with the concentration of 100-;

b) and placing the solenoid valve coil after the primary electroplating of the primary nickel priming solution in the secondary priming solution, wherein the secondary priming solution is prepared from organic additives: succinic acid, fatty acids, and thioglycolic acid; inorganic additives: sodium fluoride and water, wherein succinic acid, fatty acid, thioglycollic acid and sodium fluoride are mixed at a ratio of 2:1:1:1, and are stirred for 3-5min at 15-20 ℃, the electroplating time is 10-15min, the anode current is increased, and the deposition of nickel is promoted;

c) placing the solenoid valve coil subjected to secondary nickel electroplating in a tertiary bottoming solution, wherein the tertiary bottoming solution consists of a brightening agent, a softening agent, a wetting agent, an impurity removing agent and water, the ratio of the brightening agent to the softening agent to the wetting agent to the impurity removing agent is 1:1:1:1, stirring for 3-5min in an environment at 20-35 ℃, placing the solenoid valve coil in a plating barrel, and electroplating for 10-15min at a power supply voltage of 5-10V.

Compared with the prior art, the invention can achieve the following beneficial effects:

1. the invention can effectively control the pH value of the solution, avoid the problems of increased holes, reduced glossiness and reduced hardness caused by alkaline pH value when the cathode current efficiency is lower than that of the anode, and improve the nickel plating effect.

Detailed Description

The present invention will be further described with reference to specific embodiments for the purpose of facilitating an understanding of technical means, characteristics of creation, objectives and functions realized by the present invention, but the following embodiments are only preferred embodiments of the present invention, and are not intended to be exhaustive. Based on the embodiments in the implementation, other embodiments obtained by those skilled in the art without any creative efforts belong to the protection scope of the present invention. The experimental methods in the following examples are conventional methods unless otherwise specified, and materials, reagents and the like used in the following examples are commercially available unless otherwise specified.

Example 1:

a) placing a solenoid valve coil in a primary nickel priming solution, wherein the primary nickel priming solution consists of nickel sulfate with the concentration of 120g/L, nickel acetate with the concentration of 30g/L, boric acid with the concentration of 25g/L and an aqueous solution, the ratio of nickel sulfate to nickel acetate is 3:1, the pH value of the solution is controlled to be 3.9, checking the current efficiency of a cathode/anode, judging the change range of the pH value, continuously adding boric acid when the current efficiency of the cathode is lower than that of the anode and the pH value is alkaline, arranging a heating device at the bottom of a solution bottle, controlling the temperature of the solution to be 25 ℃, and electroplating for 12 min;

b) and placing the solenoid valve coil after the primary electroplating of the primary nickel priming solution in the secondary priming solution, wherein the secondary priming solution is prepared from organic additives: succinic acid, fatty acids, and thioglycolic acid; inorganic additives: sodium fluoride and water, wherein succinic acid, fatty acid, thioglycollic acid and sodium fluoride are mixed in a ratio of 2:1:1:1, and are stirred for 3min at 15 ℃, the electroplating time is 10min, the anode current is increased, and the deposition of nickel is promoted;

c) placing the solenoid valve coil subjected to secondary nickel electroplating in a tertiary bottoming solution, wherein the tertiary bottoming solution consists of a brightening agent, a softening agent, a wetting agent, an impurity removing agent and water, the ratio of the brightening agent to the softening agent to the wetting agent to the impurity removing agent is 1:1:1:1, stirring for 3min in an environment at 20 ℃, placing the solenoid valve coil in a plating barrel, and electroplating for 10min at a power supply voltage of 5V.

Example 2:

a) placing a solenoid valve coil in a primary nickel priming solution, wherein the primary nickel priming solution consists of 130g/L of nickel sulfate, 40g/L of nickel acetate, 35g/L of boric acid and an aqueous solution, the ratio of nickel sulfate to nickel acetate is 3:1, the pH value of the solution is controlled to be 4, checking the current efficiency of a cathode/an anode, judging the change range of the pH value, continuously adding boric acid when the current efficiency of the cathode is lower than that of the anode and the pH value is alkaline, arranging a heating device at the bottom of a solution bottle, controlling the temperature of the solution to be 20 ℃, and carrying out electroplating for 11 min;

b) and placing the solenoid valve coil after the primary electroplating of the primary nickel priming solution in the secondary priming solution, wherein the secondary priming solution is prepared from organic additives: succinic acid, fatty acids, and thioglycolic acid; inorganic additives: sodium fluoride and water, wherein succinic acid, fatty acid, thioglycollic acid and sodium fluoride are mixed in a ratio of 2:1:1:1, stirring is carried out for 5min at 16 ℃, and electroplating time is 15min, so that anode current is increased, and nickel deposition is promoted;

c) placing the solenoid valve coil subjected to secondary nickel electroplating in a tertiary bottoming solution, wherein the tertiary bottoming solution consists of a brightening agent, a softening agent, a wetting agent, an impurity removing agent and water, the ratio of the brightening agent to the softening agent to the wetting agent to the impurity removing agent is 1:1:1:1, stirring for 5min in an environment at 25 ℃, placing the solenoid valve coil in a plating barrel, and electroplating for 15min at a power supply voltage of 5V.

Example 3:

a) placing a solenoid valve coil in a primary nickel priming solution, wherein the primary nickel priming solution consists of 140g/L of nickel sulfate, 45g/L of nickel acetate, 45g/L of boric acid and an aqueous solution, the ratio of nickel sulfate to nickel acetate is 3:1, the pH value of the solution is controlled to be 4, checking the current efficiency of a cathode/an anode, judging the change range of the pH value, continuously adding boric acid when the current efficiency of the cathode is lower than that of the anode and the pH value is alkaline, arranging a heating device at the bottom of a solution bottle, controlling the temperature of the solution to be 20-35 ℃, and electroplating for 15 min;

b) and placing the solenoid valve coil after the primary electroplating of the primary nickel priming solution in the secondary priming solution, wherein the secondary priming solution is prepared from organic additives: succinic acid, fatty acids, and thioglycolic acid; inorganic additives: sodium fluoride and water, wherein succinic acid, fatty acid, thioglycollic acid and sodium fluoride are mixed at a ratio of 2:1:1:1, and are stirred for 3-5min at 15-20 ℃, the electroplating time is 10-15min, the anode current is increased, and the deposition of nickel is promoted;

c) placing the solenoid valve coil subjected to secondary nickel electroplating in a tertiary bottoming solution, wherein the tertiary bottoming solution consists of a brightening agent, a softening agent, a wetting agent, an impurity removing agent and water, the ratio of the brightening agent to the softening agent to the wetting agent to the impurity removing agent is 1:1:1:1, stirring for 5min in an environment at 35 ℃, placing the solenoid valve coil in a plating barrel, and electroplating for 10-15min at a power supply voltage of 10V.

Example 4:

a) placing a solenoid valve coil in a primary nickel priming solution, wherein the primary nickel priming solution consists of 150g/L of nickel sulfate, 65g/L of nickel acetate, 50g/L of boric acid and an aqueous solution, the ratio of nickel sulfate to nickel acetate is 3:1, the pH value of the solution is controlled to be 5, checking the current efficiency of a cathode/an anode, judging the change range of the pH value, continuously adding boric acid when the current efficiency of the cathode is lower than that of the anode and the pH value is alkaline, arranging a heating device at the bottom of a solution bottle, controlling the temperature of the solution to be 35 ℃, and carrying out electroplating for 115 min;

b) and placing the solenoid valve coil after the primary electroplating of the primary nickel priming solution in the secondary priming solution, wherein the secondary priming solution is prepared from organic additives: succinic acid, fatty acids, and thioglycolic acid; inorganic additives: sodium fluoride and water, wherein succinic acid, fatty acid, thioglycollic acid and sodium fluoride are mixed in a ratio of 2:1:1:1, and are stirred for 5min at the temperature of 20 ℃, the electroplating time is 15min, the anode current is increased, and the deposition of nickel is promoted;

c) placing the solenoid valve coil subjected to secondary nickel electroplating in a tertiary bottoming solution, wherein the tertiary bottoming solution consists of a brightening agent, a softening agent, a wetting agent, an impurity removing agent and water, the ratio of the brightening agent to the softening agent to the wetting agent to the impurity removing agent is 1:1:1:1, stirring for 5min in an environment at 35 ℃, placing the solenoid valve coil in a plating barrel, and electroplating for 15min at a power supply voltage of 10V

The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, and the preferred embodiments of the present invention are described in the above embodiments and the description, and are not intended to limit the present invention. The scope of the invention is defined by the appended claims and equivalents thereof.