POST-PLATING TREATMENT METHOD FOR ONE-STEP BRASS-ELECTROPLATED STEEL WIRE

Abstract

Disclosed is a post-plating treatment method for a one-step brass-electroplated steel wire, comprising the following steps: electroplating the surface of the steel wire with a brass alloy; immediately washing the electroplated steel wire with cold water, removing residues from the surface of the steel wire, and blow-drying the steel wire with cold air; immersing the blow-dried steel wire in a water-based coating solution; and taking the immersed steel wire out, blow-drying the steel wire with natural air, and taking the steel wire up. The water-based coating solution comprises a polyoxyethylene organic salt, sodium hypophosphite and the balance of pure water, the polyoxyethylene organic salt comprising a salt of alkyl polyoxyethylene ether phosphate and polyoxyethylene alkylamine.

Claims

1. A post-plating treatment method for a one-step brass-electroplated steel wire, comprising the following steps: electroplating the surface of the steel wire with a brass alloy; immediately washing the electroplated steel wire with cold water, removing residue from the surface of the steel wire, and blow-drying the steel wire with cold air; immersing the blow-dried steel wire in a water-based coating solution; and taking the immersed steel wire out, blow-drying the steel wire with natural air, and taking the steel wire up.

2. The post-plating treatment method for a one-step brass-electroplated steel wire according to claim 1, wherein, the water-based coating solution comprises a polyoxyethylene organic salt and sodium hypophosphite and the balance of pure water.

3. The post-plating treatment method for a one-step brass-electroplated steel wire according to claim 2, wherein, the polyoxyethylene organic salt comprises a salt of alkyl polyoxyethylene ether phosphate and polyoxyethylene alkylamine.

4. The post-plating treatment method for a one-step brass-electroplated steel wire according to claim 3, wherein, the salt of alkyl polyoxyethylene ether phosphate is one of a potassium salt of alkyl polyoxyethylene ether phosphate, a sodium salt of alkyl polyoxyethylene ether phosphate and triethanolamine.

5. The post-plating treatment method for a one-step brass-electroplated steel wire according to claim 3, wherein, by weight, provided are total 100 parts of the water-based coating solution, comprising 5-10 parts of the polyoxyethylene organic salt, 0.5-2 parts of sodium hypophosphite and the balance of pure water.

6. The post-plating treatment method for a one-step brass-electroplated steel wire according to claim 5, wherein, the 5-10 parts of the polyoxyethylene organic salt comprise 0.5-2 parts of polyoxyethylene alkylamine and the balance of the salt of alkyl polyoxyethylene ether phosphate.

7. The post-plating treatment method for a one-step brass-electroplated steel wire according to claim 1, wherein, the steel wire is immersed in the water-based coating solution for 4±1 s.

8. The post-plating treatment method for a one-step brass-electroplated steel wire according to claim 1, wherein, the water-based coating solution has a pH value of 8±0.3 and a temperature of 65-85° C.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0020] FIG. 1 shows the three-day 80° C./80% damp-heat aging comparison between the brass-electroplated steel wires according to embodiments of the invention and the conventional steel wire.

DETAILED DESCRIPTION OF THE INVENTION

[0021] The invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the invention, rather than limiting the scope of the invention.

Example 1

[0022] 4.5 parts of potassium alkyl polyoxyethylene ether phosphate, 0.5 part of polyoxyethylene alkyl amine, 0.5 part of sodium phosphite and pure water were mixed to obtain 100 parts of a water-based coating solution, the pH of the water-based coating solution was adjusted to 7.7 with KOH, and the coating solution was then heated to 65° C. The one-step brass-electroplated steel wire was washed with water and then passed through the coating solution immediately with a residence time of 4 s, and the wire was then taken up. Part of the steel wire was taken as the sample SY1 for the 80° C./80% damp-heat aging test and the surface ZnO content aging test to verify the corrosion resistance of the coating surface of the steel wire.

Example 2

[0023] 6 parts of potassium alkyl polyoxyethylene ether phosphate, 1.2 parts of polyoxyethylene alkyl amine, 1.2 parts of sodium phosphite and pure water were mixed to obtain 100 parts of a water-based coating solution, the pH of the water-based coating solution was adjusted to 8.0 with KOH, and the coating solution was then heated to 75° C. The one-step brass-electroplated steel wire was washed with water and then passed through the coating solution immediately with a residence time of 4 s, and the wire was then taken up. Part of the steel wire was taken as the sample SY2 for the 80° C./80% damp-heat aging test and the surface ZnO content aging test to verify the corrosion resistance of the coating surface of the steel wire.

Example 3

[0024] 8 parts of potassium alkyl polyoxyethylene ether phosphate, 2 parts of polyoxyethylene alkyl amine, 2 parts of sodium phosphite and pure water were mixed to obtain 100 parts of a water-based coating solution, the pH of the water-based coating solution was adjusted to 8.0 with KOH, and the coating solution was then heated to 85° C. The one-step brass-electroplated steel wire was washed with water and then passed through the coating solution immediately with a residence time of 4 s, and the wire was then taken up. Part of the steel wire was taken as the sample SY3 for the 80° C./80% damp-heat aging test and the surface ZnO content aging test to verify the corrosion resistance of the coating surface of the steel wire.

Comparative Example 4

[0025] 15 parts of potassium alkyl polyoxyethylene ether phosphate, 5 parts of polyoxyethylene alkyl amine, 5 parts of sodium phosphite and pure water were mixed to obtain 100 parts of a water-based coating solution, the pH of the water-based coating solution was adjusted to 8.0 with KOH, and the coating solution was then heated to 80° C. The one-step electroplated-brass steel wire was washed with water and passed through the coating solution immediately with a residence time of 4 s, and the steel wire was then taken up. Since the concentration was too high, the surface of the steel wire was not easy to dry, and the coating was thick, which is not conducive to the use for subsequent drawing.

Comparative Example 5

[0026] 6 parts of potassium alkyl polyoxyethylene ether phosphate, 1.2 parts of polyoxyethylene alkyl amine, 1.2 parts of sodium phosphite and pure water were mixed to obtain 100 parts of a water-based coating solution, the pH of the water-based coating solution was adjusted to 8.0 with KOH, and the coating solution was then heated to 55° C. The one-step electroplated-brass steel wire was washed with water and passed through the coating solution immediately with a residence time of 4 s, and the steel wire was then taken up. Since the temperature was too low, the surface of the steel wire was not easy to dry.

Comparative Example 6

[0027] 6 parts of potassium alkyl polyoxyethylene ether phosphate, 1.2 parts of polyoxyethylene alkyl amine, 1.2 parts of sodium phosphite and pure water were mixed to obtain 100 parts of a water-based coating solution, the pH of the water-based coating solution was adjusted to 8.0 with KOH, and the coating solution was then heated to 80° C. The one-step electroplated-brass steel wire was washed with water and passed through the coating solution immediately with a residence time of 6 s, and the steel wire was then taken up. Since the treatment was too long and the surface coating of the steel wire was too thick, the surface of the steel wire was not easy to dry.

Comparative Example 7

[0028] Part of the conventional thermal diffusion brass-electroplated steel wire in the same period was taken as the sample CG for the 80° C./80% damp-heat aging test and the surface ZnO content aging test to compare with the steel wire of the invention patent in terms of the corrosion resistance of the coating surface.

[0029] FIG. 1 shows the three-day 80° C./80% damp-heat aging comparison between the brass steel wires according to the examples of the invention and the conventional steel wire. SY1, SY2, and SY3 are the steel wires treated according to Examples 1 to 3 of the invention, respectively, and CG is a conventional steel wire. It can be seen that the surface of the brass-electroplated steel wire treated according to the invention becomes dark without large rust spots after three days of damp-heat aging, while the surface coating of the conventional steel wire has rust and becomes back. Table 1 shows the surface ZnO content data of the brass-electroplated steel wires obtained according to the examples and the conventional steel wire tracked for a period of 2 months. As can be seen from Table 1, compared with the conventional steel wire, the brass-electroplated steel wire obtained according to the invention has lower surface ZnO content and slower surface oxidation and the requirements of wet drawing for the surface ZnO content of the brass-electroplated steel wire can be met.

TABLE-US-00001 Surface ZnO contents of the brass-electroplated steel wires of the invention and the conventional steel wire Sample No. Surface ZnO content (mg/m.sup.2) 1 day 60 days SY1 24.6 54.8 SY2 18.2 45.6 SY3 23.5 49.3 CG 32.9 58.3

[0030] The above are only the preferred embodiments of the invention. It should be pointed out that for those skilled in the art, without departing from the principles of the invention, several improvements and modifications can also be made, and these improvements and modifications should also be regarded as falling within the scope of the invention.