CN-121976177-A - Repairing method and application of copper alloy protective film

Abstract

The invention discloses a repairing method and application of a copper alloy protective film. The repair method comprises the step of contacting a damaged area of the copper alloy protective film with a chlorine-containing solution in a magnetic field. The invention simulates the process of membrane damage-regeneration of copper alloy in marine environment, and the result shows that the application of magnetic field accelerates the primary regeneration of the membrane and the recovery of corrosion resistance, changes the local pH condition through the synergistic effect with the scratch micro-area, inhibits the redeposition of Cu 2 O, remarkably enhances the enrichment of metal oxides except copper in the alloy on the surface of the regenerated membrane, and finally forms a single-layer membrane structure with enhanced corrosion resistance.

Inventors

• GONG KE
• WANG LIPING
• MAO FEIXIONG
• WANG JIAMU
• HU XIUQI
• YANG MINGSI
• WANG YUANMING

Assignees

• 中国科学院宁波材料技术与工程研究所

Dates

Publication Date

20260505

Application Date

20251202

Priority Date

20251105

Claims (10)

1. 1. A method for repairing a copper alloy protective film is characterized by comprising the step of contacting a damaged area of the copper alloy protective film with a chlorine-containing solution in a magnetic field.
2. 2. The repairing method according to claim 1, wherein the strength of the magnetic field is more than 0.05T, preferably 0.1-0.4T; and/or the direction of the magnetic field is vertical to the surface of the copper alloy protective film.
3. 3. The method according to claim 1, wherein the method comprises bringing the damaged region of the copper alloy protective film into contact with the chlorine-containing solution in a magnetic field at normal temperature to thereby effect repair of the copper alloy protective film.
4. 4. The method of repairing a copper alloy protective film according to claim 3, wherein the time for contacting the damaged area of the copper alloy protective film with the chlorine-containing solution is controlled to be 120 hours or longer.
5. 5. The method for repairing a copper alloy according to claim 1, wherein the copper alloy protective film is formed on the surface of the copper alloy by immersing the copper alloy in a chlorine-containing solution at normal temperature.
6. 6. The method for repairing a vessel according to claim 1, wherein the chlorine-containing solution comprises NaCl solution and/or KCl solution; and/or the concentration of chloride ions in the chlorine-containing solution is 0.2-1 mol/L.
7. 7. The method of repairing of claim 1, wherein the copper alloy comprises a copper nickel alloy.
8. 8. A rapid repair method for a copper alloy pipeline protective film is characterized by comprising the step of contacting at least a damaged area of the copper alloy pipeline protective film with a chlorine-containing solution in a magnetic field.
9. 9. The rapid repair method according to claim 8, wherein the protective film comprises a copper alloy protective film, preferably the copper alloy protective film comprises a copper nickel alloy oxide film.
10. 10. A method of protecting a surface of a copper alloy, comprising: Forming a protective film on the surface of the copper alloy; And contacting at least the damaged area of the copper alloy protective film with a chlorine-containing solution in a magnetic field.

Description

Repairing method and application of copper alloy protective film Technical Field The invention belongs to the technical field of ocean protection, and particularly relates to a repairing method and application of a copper alloy protective film. Background Copper alloy becomes a key material of pipelines in marine environment due to its excellent heat conductivity and seawater corrosion resistance. It is widely used in condensers and heat exchanger tubes in coastal power plants and ships. Copper alloys exhibit superior properties under extreme conditions and are therefore particularly favored. The corrosion resistance of copper alloys in seawater is attributed to the double-layer protective film formed on the surface thereof, in particular copper-nickel alloys, which are inner films composed of Cu 2 O and NiO. The addition of Ni reduces the concentration of cation vacancies in Cu 2 O, thereby enhancing its corrosion resistance. The existence of NiO further improves the electrical resistance and provides effective protection for the alloy matrix. In addition, some prior studies have proposed strategies to further enhance the corrosion resistance of copper alloys, including alloy modification and preforming of protective films. The alloy modification is to promote the rapid formation of a more stable and compact oxide layer in the early stage of service by introducing trace elements. Pre-film formation techniques, such as pretreatment with sodium dichromate or ferrous sulfate, facilitate the formation of protective films before the material is put into use. Copper alloys exhibit excellent corrosion resistance when the film remains intact. However, copper alloy pipelines are often subject to erosion by solid particles in seawater in practical applications. This process breaks the protective film on the surface of the pipe, resulting in the formation of scratches. The scratched areas are significantly more prone to localized perforation, ultimately accelerating early failure of the pipe. This damage breaks the protective film on the surface, exposing the alloy substrate to the marine environment, and significantly accelerates localized corrosion. At the same time, the regenerated protective film requires a longer growth cycle to restore its corrosion resistance, during which it is still extremely vulnerable to further damage. This results in a progressive thinning of the alloy matrix in the scratched areas, eventually leading to perforation. Furthermore, corrosion in pipelines is "contagious" and once it occurs at a point it spreads rapidly, possibly causing more serious damage if not repaired in time. Therefore, the rapid and efficient restoration of the integrity and corrosion resistance of protective films is a key challenge in extending the useful life of the pipe. However, repair of damaged protective films becomes exceptionally difficult due to the complex structure of the pipe and the expensive disassembly and handling. Disclosure of Invention The invention mainly aims to provide a repairing method and application of a copper alloy protective film, so as to overcome the defects of the prior art. In order to achieve the purpose of the invention, the technical scheme adopted by the invention comprises the following steps: The embodiment of the invention provides a repair method of a copper alloy protective film, which comprises the step of contacting a damaged area of the copper alloy protective film with a chlorine-containing solution in a magnetic field. The embodiment of the invention also provides a rapid repair method of the copper alloy pipeline protective film, which comprises the step of contacting at least the damaged area of the copper alloy pipeline protective film with chlorine-containing solution in a magnetic field. The embodiment of the invention also provides a surface protection method of the copper alloy, which comprises the following steps: Forming a protective film on the surface of the copper alloy; And contacting at least the damaged area of the copper alloy protective film with a chlorine-containing solution in a magnetic field. Compared with the prior art, the invention has the beneficial effects that the film damage-regeneration process of the copper alloy in the marine environment is simulated, and the result shows that the application of the magnetic field accelerates the primary regeneration and the recovery of corrosion resistance of the film, changes the local pH condition through the synergistic effect with the scratch micro-area, inhibits the redeposition of Cu 2 O, remarkably enhances the enrichment of metal oxides except copper elements in the copper alloy on the surface of the regenerated film, and finally forms a single-layer film structure with enhanced corrosion resistance. Drawings In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings that are required to be used in the embodiments or th