Large-coil-weight copper material after surface treatment and surface anti-oxidation treatment method of large-coil-weight copper material

Abstract

The invention provides a large-coil heavy copper material subjected to surface treatment and a surface anti-oxidation treatment method of the large-coil heavy copper material. The treatment method comprises the following steps: S1, sequentially carrying out degreasing and oil removal treatment and acid cleaning treatment on the large-roll heavy copper material to obtain a pretreated large-roll heavy copper material; s2, the pretreated large-coil heavy copper material serves as a working electrode, the working electrode, a reference electrode, a counter electrode and a first electrolyte solution sequentially pass through an electrochemical oxidation treatment tank and an electrochemical reduction treatment tank, and the pretreated large-coil heavy copper material is sequentially subjected to a continuous oxidation reaction and a continuous reduction reaction in the treatment tanks, the large-coil heavy copper material after electrochemical treatment is obtained; s3, the large-coil heavy copper material subjected to electrochemical treatment is sequentially cleaned and dried, and surface anti-oxidation treatment on the large-coil heavy copper material is completed; and the pH value of the surface treatment liquid is 6-10. The preparation process disclosed by the invention can be used for carrying out surface treatment on the large-coil-weight copper material, and large-scale surface treatment of the large-coil-weight copper material is realized.

Description

Technical Field

[0001] The invention relates to the technical field of surface treatment of copper and its alloys, and in particular to a large coil heavy copper material after surface treatment and a surface anti-oxidation treatment method of the large coil heavy copper material. Background Art

[0002] Copper alloys will be oxidized, discolored and corroded due to various factors during production, transportation, storage and use. Especially in an environment where the relative humidity exceeds the critical humidity, sulfur dioxide is oxidized by water molecules to SO3 to form a weakly acidic H2SO4 environment, chloride particles in the air in coastal areas, haze days, and a large amount of acidic dust and smoke in environmentally polluted areas, as well as alkaline conditions, increase the probability of copper materials being oxidized and discolored, which makes people eager to find a surface protection technology that can maintain the superior electrical and thermal conductivity of copper and its alloys and have excellent corrosion resistance. At the same time, large coils can be processed online continuously at room temperature. However, there is no research work in this area at home and abroad.

[0003] Therefore, it is necessary to develop a simple, efficient, and continuous online real-time processing technology for the surface corrosion and oxidation resistance of large-volume heavy copper materials at room temperature to solve the problem of oxidation and discoloration of large-volume heavy copper strips, foils, and wires during production, transportation, storage, and use. Summary of the invention

[0004] The main purpose of the present invention is to provide a large coil of heavy copper material after surface treatment and a surface antioxidant treatment method for the large coil of heavy copper material, so as to solve the problem that the large coil of heavy copper material obtained by the surface antioxidant treatment method in the prior art is prone to oxidation discoloration.

[0005] In order to achieve the above-mentioned purpose, according to one aspect of the present invention, a surface antioxidant treatment method for a large-volume heavy copper material is provided, and the surface antioxidant treatment method comprises: step S1, degreasing and deoiling treatment and acid cleaning treatment are sequentially performed on the large-volume heavy copper material to obtain the pretreated large-volume heavy copper material; step S2, using the pretreated large-volume heavy copper material as a working electrode, assembling the working electrode, the reference electrode, the counter electrode and the first electrolyte solution into a three-electrode system, and passing the three-electrode system sequentially through an electrochemical oxidation treatment tank and an electrochemical reduction treatment tank, and the pretreated large-volume heavy copper material is sequentially subjected to continuous oxidation reaction and continuous reduction reaction in the electrochemical oxidation treatment tank and the electrochemical reduction treatment tank to obtain the electrochemically treated large-volume heavy copper material; step S3, sequentially cleaning and drying the electrochemically treated large-volume heavy copper material to complete the surface antioxidant treatment of the large-volume heavy copper material; wherein the electrolyte solution is a surface treatment liquid, and the surface treatment liquid comprises water, formate and a polar solvent; and the pH value of the surface treatment liquid is 6 to 10.

[0006] Furthermore, the above-mentioned continuous oxidation reaction is carried out by cyclic voltammetry, the temperature of the cyclic voltammetry is 20° C. to 40° C., and / or the scanning number of the cyclic voltammetry is 2 to 8 circles, and / or the scanning time of the cyclic voltammetry is 2 min to 10 min.

[0007] Furthermore, the above-mentioned continuous reduction reaction is carried out by constant potential deposition method, the potential of the constant potential deposition method is -5V to 5V, and / or the scanning speed of the constant potential deposition method is 0.1mV / s to 100mV / s, and / or the processing time of the constant potential deposition method is 3min to 10min.

[0008] Furthermore, in the above-mentioned surface treatment liquid, the ratio of the volume of water, the mass of formate and the volume of the polar solvent is 1-5L:10-30g:5-10mL; and / or the water is deionized water; and / or the polar solvent is a mixture of dimethylformamide and methyl acetate, preferably the volume ratio of dimethylformamide to methyl acetate is 30-40:60-70; preferably, the formate is selected from any one or more of sodium formate, potassium formate, calcium formate and magnesium formate.

[0009] Furthermore, the above-mentioned large-volume heavy copper material is any one or more of large-volume heavy copper strip, large-volume heavy copper foil and large-volume heavy copper rod; and / or, the models of the large-volume heavy copper material are independently selected from any one or more of C10100, C10200, C11000, C19400, C18150, C36000, C52100 and C70600.

[0010] Furthermore, the above-mentioned step S3 includes: subjecting the large coil of heavy copper material after electrochemical treatment to corrosion inhibitor surface treatment and then washing and drying, wherein the treatment liquid used for the corrosion inhibitor surface treatment is a benzotriazole solution, and the mass concentration of the benzotriazole solution is 8-15wt%; and / or the temperature of the corrosion inhibitor surface treatment is 40-60°C; and / or the time of the benzotriazole surface treatment is 40-60s.

[0011] Furthermore, the reference electrode is a saturated calomel electrode or Ag / AgCl; and / or the counter electrode is a Pt electrode or a graphite electrode.

[0012] Furthermore, the degreasing and oil removal treatment is performed using a degreasing agent, and / or the degreasing agent is an alkaline degreasing agent; and / or the temperature of the degreasing and oil removal treatment is 30 to 50° C.; and / or the time of the degreasing and oil removal treatment is 30 to 60 seconds.

[0013] Furthermore, an acid cleaning treatment is performed using an acid cleaning solution, wherein the acid cleaning solution is an aqueous sulfuric acid solution with a mass concentration of 8 to 12 wt %; and / or the acid cleaning treatment time is 40 to 80 seconds.

[0014] According to another aspect of the present invention, a surface-treated heavy-duty copper coil is provided. The surface-treated heavy-duty copper coil is obtained by the aforementioned surface anti-oxidation treatment method.

[0015] By applying the technical solution of the present invention, the surface antioxidant treatment method of the present application removes oil stains, oxides, etc. on the surface of the large-volume heavy copper material by sequentially performing degreasing and oil removal treatment and acid cleaning treatment on the large-volume heavy copper material, thereby obtaining a pretreated large-volume heavy copper material with a fresh and clean surface. The pretreated large-volume heavy copper material is subjected to a continuous oxidation reaction by a three-electrode system so that the surface of the pretreated large-volume heavy copper material is in an oxidized state, that is, a Cu (110) structural layer is formed on its surface, and then the copper material after the oxidation reaction is subjected to a continuous reduction reaction to obtain an electrochemically treated large-volume heavy copper material. During the continuous reduction reaction, the Cu (110) structural layer combines with the formate ions in the formate, thereby forming a progressive valence structure, and in the direction from the inside to the outside of the electrochemically treated large-volume heavy copper material, the secondary layer is formed with copper atoms with a valence of +1, and the outermost layer is formed with copper atoms with a valence of +2. Since the +2-valent copper atoms in the outermost layer of the large-volume heavy copper material have been combined with formate ions after electrochemical treatment, they are in an oxidized state. When external oxygen and other adsorbates combine with the +2-valent copper atoms in the outermost layer, the adsorption of formate ions needs to be overcome, and the oxidation kinetics of formate ions are relatively slow, so that the copper material surface presents excellent anti-corrosion and anti-oxidation effects. Finally, after further treatment by corrosion inhibitor surface treatment, the large-volume heavy copper material presents a more excellent protective effect. As can be seen from the above, the preparation process of the present invention can be used to carry out surface treatment of large-volume heavy copper materials, realize online continuous treatment of large-volume heavy copper materials, and is suitable for large-scale surface treatment of copper materials.

[0016] In addition, the entire process of the above surface antioxidant treatment method can be carried out at room temperature, making the above treatment process more broad-spectrum. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0018] Figure 1 The comparison results of polarization curves of heavy-weight C10100 copper strip before and after treatment according to Example 1 of the present invention are shown;

[0019] Figure 2 The XRD comparison results of the heavy-weight C10100 copper strip before and after treatment according to Example 1 of the present invention are shown;

[0020] Figure 3 The EBSD test results of the heavy-weight C10100 copper strip before treatment according to Example 1 of the present invention are shown;

[0021] Figure 4 The optical photographs of the surfaces of the treated sample of the heavy-weight C10100 copper strip according to Example 1 of the present invention and the untreated sample in Comparative Example 1 after being immersed in a 1 mol / L NaOH solution for 24 hours are shown;

[0022] Figure 5 The SEM image of the heavy-weight C10100 copper strip treated sample according to Example 1 of the present invention after being immersed in a 1 mol / L NaOH solution for 24 hours is shown;

[0023] Figure 6 The SEM image of the untreated sample in Comparative Example 1 after being immersed in 1 mol / L NaOH solution for 24 hours is shown. DETAILED DESCRIPTION

[0024] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0025] As analyzed in the background technology of this application, the large-scale heavy copper coil obtained by the surface antioxidant treatment method in the prior art is prone to oxidation discoloration. In order to solve this problem, this application provides a large-scale heavy copper coil after surface treatment and a surface antioxidant treatment method for large-scale heavy copper coil.

[0026] In a typical embodiment of the present application, a surface antioxidant treatment method for a large-volume heavy copper material is provided, and the surface antioxidant treatment method comprises: step S1, sequentially performing degreasing and oil removal treatment and acid cleaning treatment on the large-volume heavy copper material to obtain the pretreated large-volume heavy copper material; step S2, using the pretreated large-volume heavy copper material as a working electrode, assembling the working electrode, the reference electrode, the counter electrode and the first electrolyte solution into a three-electrode system, and sequentially passing the three-electrode system through an electrochemical oxidation treatment tank and an electrochemical reduction treatment tank, and the pretreated large-volume heavy copper material sequentially undergoes continuous oxidation reaction and continuous reduction reaction in the electrochemical oxidation treatment tank and the electrochemical reduction treatment tank to obtain the electrochemically treated large-volume heavy copper material; step S3, sequentially cleaning and drying the electrochemically treated large-volume heavy copper material to complete the surface antioxidant treatment of the large-volume heavy copper material; wherein the electrolyte solution is a surface treatment liquid, and the surface treatment liquid comprises water, formate and a polar solvent; and the pH value of the surface treatment liquid is 6 to 10.

[0027] The surface antioxidant treatment method of the present application sequentially performs degreasing and oil removal treatment and acid cleaning treatment on the large coil heavy copper material, so that the oil stains, oxides, etc. on the surface of the large coil heavy copper material are removed, and the surface of the pretreated large coil heavy copper material is obtained. The continuous oxidation reaction of the pretreated large coil heavy copper material by the three-electrode system makes the surface of the pretreated large coil heavy copper material oxidized, that is, a Cu (110) structural layer is formed on its surface, and then the copper material after the oxidation reaction is subjected to a continuous reduction reaction to obtain the electrochemically treated large coil heavy copper material. In the process of the continuous reduction reaction, the Cu (110) structural layer combines with the formate ions in the formate, thereby forming a progressive valence structure, and the large coil heavy copper material after the electrochemical treatment sequentially forms a secondary layer of copper atoms with a valence of +1 and an outermost layer of copper atoms with a valence of +2 in the direction from the inside to the outside. Since the outermost +2-valent copper atoms of the large-volume heavy copper material have been combined with formate ions and present an oxidized state after electrochemical treatment, when external oxygen and other adsorbates combine with the outermost +2-valent copper atoms, it is necessary to overcome the adsorption of formate ions, and the oxidation kinetics of formate ions are relatively slow, so that the copper surface presents excellent anti-corrosion and anti-oxidation effects, and finally after further treatment by corrosion inhibitor surface treatment, the large-volume heavy copper material presents excellent protective effects. As can be seen from the above, the preparation process of the present invention can be used to carry out surface treatment of large-volume heavy copper materials, realize online continuous treatment of large-volume heavy copper materials, and is suitable for large-scale surface treatment of copper materials. In addition, the entire process of the above surface antioxidant treatment method can be carried out at room temperature, so that the above treatment process is more broad-spectrum.

[0028] In addition, the pH value of the surface treatment liquid is controlled within the above range to match the pH value of the surface treatment liquid with the potential of the reduction reaction, forming a surface treatment layer with suitable thickness and excellent reconstructed surface quality, thereby improving the quality and uniformity of the surface reconstruction layer. In addition, the optimization of the pH value not only promotes the adsorption and reaction of formate ions on the surface of the copper material, but also reduces the risk of material damage that may be caused by over-acid or over-alkali conditions, ensuring that the conductivity of the copper material is not affected, while improving the efficiency and quality of the copper material surface reconstruction.

[0029] In one embodiment of the present application, the above-mentioned continuous oxidation reaction is carried out by cyclic voltammetry, the temperature of the cyclic voltammetry is 20°C to 40°C, and / or the scanning number of the cyclic voltammetry is 2 to 8 circles, and / or the scanning time of the cyclic voltammetry is 2 min to 10 min.

[0030] The conditions of cyclic voltammetry are preferably controlled within the above range to ensure that the oxidation reaction in the electrochemical oxidation treatment tank can proceed stably, which is beneficial to control the thickness and structure of the oxide layer, thereby enhancing the uniformity and effect of the surface treatment, and ultimately achieving excellent corrosion resistance on the surface of large-volume heavy copper materials.

[0031] In one embodiment of the present application, the above-mentioned continuous reduction reaction is carried out by a constant potential deposition method, the potential of the constant potential deposition method is -5V to 5V, and / or the scanning speed of the constant potential deposition method is 0.1mV / s to 100mV / s, and / or the processing time of the constant potential deposition method is 3min to 10min.

[0032] The conditions of the constant potential deposition method are preferably controlled within the above range to ensure that the +2-valent copper atoms and formate ions can be accurately controlled to form a stable combination during the reduction treatment of the copper surface, thereby forming a progressive valence structure protective layer, the outermost layer is +2-valent copper atoms, and the second layer is +1-valent copper atoms, thereby effectively preventing oxygen and corrosive substances in the external environment from directly contacting the copper surface, significantly enhancing the antioxidant ability and corrosion resistance of the copper.

[0033] In one embodiment of the present application, in the above-mentioned surface treatment liquid, the ratio of the volume of water, the mass of formate and the volume of the polar solvent is 1-5L:10-30g:5-10mL; and / or the water is deionized water; and / or the polar solvent is a mixture of dimethylformamide and methyl acetate, preferably the volume ratio of dimethylformamide to methyl acetate is 30-40:60-70; preferably, the formate is selected from any one or more of sodium formate, potassium formate, calcium formate and magnesium formate.

[0034] The volume of water, the mass of formate and the volume ratio of the polar solvent are preferably controlled within the above range to ensure that the surface treatment solution can play the best effect in the electrochemical oxidation and reduction process. By optimizing the composition of the polar solvent and the type of formate, as well as the purity of the deionized water, an ideal reaction medium is provided for the reconstruction of the copper surface, which is conducive to forming a uniform and dense surface treatment layer, and further enhancing the oxidation resistance and corrosion resistance of the copper. Specifically, the polar solvent is preferably a mixture of ethyl acetate and dimethylformamide, and acts together with the formate ions in the formate, which can effectively surround the surface of the copper material, forming a spatial barrier, so that the negative ions cannot approach, and only the positive ions are associated, thereby reducing the risk of oxidation and discoloration of the copper material during the electrochemical process. The above types of formate are preferably helpful for it to effectively dissociate into monodentate formate in the solution, which can be converted into a more stable bidentate formate during the electrochemical reduction process, and has higher activity and stability on the Cu (110) surface. It is further preferred that the volume ratio of the polar solvent of the mixture of dimethylformamide and ethyl acetate is 30-40:60-70, which can better exert the synergistic effect of the two solvents and further ensure the surface stability of the large-volume heavy copper material during the surface reconstruction process, thereby achieving an excellent surface reconstruction effect.

[0035] In addition, since formate will be consumed during the electrochemical surface reconstruction treatment, in order to ensure that the formate concentration in the surface treatment liquid is maintained within the optimal range required by the present invention, in order to obtain an excellent surface reconstruction layer and protective effect. In some preferred embodiments of the present application, the above-mentioned three-electrode system is provided with an automatic circulation rehydration device, that is, it is configured to adjust the concentration of the surface treatment liquid in the automatic rehydration device, especially the formate concentration. In order to better achieve the regulation of the formate concentration, a formate concentration detection device can be matched and set, the formate concentration can be monitored online, and the rehydration can be performed according to the test results to further improve the control accuracy. By real-time monitoring of the rehydration method of the surface treatment liquid, the electrochemical reconstruction of the copper surface is achieved, thereby further improving the corrosion resistance of copper materials such as large-volume heavy copper strips, foils and wires.

[0036] In one embodiment of the present application, the above-mentioned heavy copper material is any one or more of heavy copper strip, heavy copper foil and heavy copper rod; and / or, the models of the heavy copper material are independently selected from any one or more of C10100, C10200, C11000, C19400, C18150, C36000, C52100 and C70600.

[0037] The types and models of heavy-duty copper materials are preferably controlled within the above range, indicating that the surface treatment method has wide applicability, thereby ensuring that the surface reconstruction treatment of copper materials can be carried out in batches, so that the treatment method can be used in the industrial production of copper and its alloys, and also provides a guarantee for the industrial production of copper materials with high corrosion resistance and high anti-discoloration properties.

[0038] In one embodiment of the present application, the above-mentioned step S3 includes: subjecting the large coil of heavy copper material after electrochemical treatment to corrosion inhibitor surface treatment and then cleaning and drying, wherein the treatment liquid used for the above-mentioned corrosion inhibitor surface treatment is a benzotriazole solution, and the mass concentration of the benzotriazole solution is 8-15wt%; and / or the temperature of the corrosion inhibitor surface treatment is 40-60°C; and / or the time of the benzotriazole surface treatment is 40-60s.

[0039] This application ensures that a dense protective film with excellent protective performance is formed on the surface of the copper material after electrochemical treatment by controlling the treatment liquid used for corrosion inhibitor surface treatment to be a benzotriazole solution, and controlling the mass concentration of the benzotriazole solution, the surface treatment temperature, and the surface treatment time within the above range. This protective film can effectively prevent the invasion of oxygen, moisture, and other corrosive substances, forming a second protective barrier, thereby improving the durability and stability of large-volume heavy copper materials in complex environments. It also reduces the wear on the surface of large-volume heavy copper materials, especially under friction and contact conditions, thereby extending the anti-oxidation and discoloration time of large-volume heavy copper materials during transportation, storage, and use, thereby achieving a highly efficient protective effect.

[0040] In one embodiment of the present application, the reference electrode is a saturated calomel electrode or Ag / AgCl; and / or the counter electrode is a Pt electrode or a graphite electrode.

[0041] It is preferred to control the types of the reference electrode and the counter electrode within the above range, which not only provides a standard potential reference for the electrochemical treatment, but also helps to form a uniform current distribution, thereby promoting the stable adsorption and reaction of formate ions in the surface treatment solution, thereby ensuring the high quality and consistency of the surface treatment of large-volume heavy copper materials.

[0042] In one embodiment of the present application, a degreasing agent is used for the above-mentioned degreasing and oil removal treatment, and / or the degreasing agent is an alkaline degreasing agent; and / or the temperature of the degreasing and oil removal treatment is 30 to 50° C.; and / or the time of the degreasing and oil removal treatment is 30 to 60 seconds.

[0043] It is preferred to control the type of degreasing agent and the conditions of the degreasing and oil removal treatment within the above range, thereby improving the removal effect of oil stains and organic impurities on the surface of large-volume heavy copper materials, providing a clean and smooth surface for subsequent electrochemical treatment, thereby helping to improve the treatment effect and the antioxidant properties of the material, and also helping to reduce energy consumption in the pretreatment process, thereby reducing costs.

[0044] In one embodiment of the present application, the acid cleaning treatment is performed with a pickling solution, the pickling solution is an aqueous sulfuric acid solution with a mass concentration of 8 to 12 wt %; and / or the acid cleaning treatment time is 40 to 80 s.

[0045] It is preferred to control the concentration of the pickling solution and the time of the acid cleaning treatment within the above range, which is beneficial to ensure that the oxides and other inorganic impurities on the surface of the large-volume heavy copper material can be effectively removed, prepare a clean and active surface for electrochemical treatment, improve the uniformity and reactivity of the copper surface, thereby promoting the formation of a stable and uniform protective layer during the electrochemical treatment process, and further enhancing the oxidation resistance and corrosion resistance of the copper material.

[0046] In another typical embodiment of the present application, a large-coil heavy copper material after surface treatment is provided. The large-coil heavy copper material after surface treatment is obtained by the above-mentioned surface anti-oxidation treatment method.

[0047] The surface-treated heavy copper coil obtained by the above preparation method of the present application exhibits an excellent protective effect, and is more suitable for large-scale application of copper materials.

[0048] The beneficial effects of the present application will be further illustrated below in conjunction with embodiments.

[0049] Example 1

[0050] (1) The heavy C10100 copper strip is unrolled for degreasing and oil removal. The degreasing agent used for degreasing is an alkaline degreasing agent, the treatment temperature is 30°C, the treatment time is 60s, and then acid is carried out. The pickling liquid is a 10% sulfuric acid aqueous solution, the acid time is 55s, and after water washing and drying, a fresh and clean surface is obtained;

[0051] (2) A heavy-duty C10100 copper strip was used as the working electrode, the Ag / AgCl electrode was used as the reference electrode, and the Pt electrode was used as the counter electrode. Electrochemical surface treatment was carried out in a surface treatment solution using a three-electrode system. The surface treatment solution was mainly composed of deionized water, sodium formate, and a mixture of dimethylformamide and methyl acetate. The deionized water content was 2L, the polar solvent content was 7mL, and the formate content was 15g; the polar solvent was a mixture of dimethylformamide and methyl acetate, with dimethylformamide being 30% and methyl acetate being 70%. The pH of the surface treatment solution was 6.

[0052] (3) The surface treatment is carried out in four tanks, the first tank is an oxidation tank, the second tank is a reduction tank, the third tank is a BTA treatment tank, and the fourth tank is a cleaning and drying tank. The heavy C10100 copper strip passes through the oxidation tank, the reduction tank, the BTA treatment tank and the cleaning and drying tank in sequence. The oxidation tank uses cyclic voltammetry to carry out oxidation reaction, the test temperature is 20°C, the number of scans is 6, and the scan time is 7 minutes; the reduction tank uses constant potential deposition method to carry out reduction reaction, the potential is -5V~5V, the scanning speed is 30mV / s, and the treatment time is 6 minutes; the BTA treatment tank carries out BTA treatment on the copper material, the BTA treatment temperature is 50°C, the BTA content is 10%, and the treatment time is 40s; the copper strip is cleaned and dried in the cleaning and drying tank, and the heavy C10100 copper strip with surface reconstruction is obtained after winding.

[0053] The polarization curve of the large coil of heavy copper strip after treatment is shown in Table 1.

[0054] Example 2

[0055] (1) The heavy-weight C10200 copper foil is unrolled for degreasing and oil removal. The degreasing agent used for degreasing is an alkaline degreasing agent, the treatment temperature is 35°C, the treatment time is 55s, and then acid is carried out. The pickling liquid is an 8% sulfuric acid aqueous solution, the acid time is 80s, and after water washing and drying, a fresh and clean surface is obtained;

[0056] (2) Using a heavy roll of C10200 copper foil as the working electrode, a saturated calomel electrode as the reference electrode, and a graphite electrode as the counter electrode, an electrochemical surface treatment was carried out in a surface treatment solution using a three-electrode system. The surface treatment solution mainly consisted of deionized water, magnesium formate, and a mixture of dimethylformamide and methyl acetate. The deionized water content was 1L, the polar solvent content was 6mL, and the formate content was 10g; the polar solvent was a mixture of dimethylformamide and methyl acetate, with dimethylformamide being 35% and methyl acetate being 65%. The pH of the surface treatment solution was 7.

[0057] (3) The surface treatment is carried out in four tanks, the first tank is an oxidation tank, the second tank is a reduction tank, the third tank is a BTA treatment tank, and the fourth tank is a cleaning and drying tank. The heavy roll C10200 copper foil passes through the oxidation tank, the reduction tank, the BTA treatment tank and the cleaning and drying tank in sequence. The oxidation tank adopts cyclic voltammetry to carry out oxidation reaction, the test temperature is 30°C, the number of scanning circles is 2 circles, and the scanning time is 2 minutes; the reduction tank adopts constant potential deposition method to carry out reduction reaction, the potential is -4V~4V, the scanning speed is 1mV / s, and the treatment time is 3 minutes; the BTA treatment tank carries out BTA treatment on the copper material, the BTA treatment temperature is 40°C, the BTA content is 8%, and the treatment time is 42 seconds; the copper foil is cleaned and dried in the cleaning and drying tank, and the heavy roll C10200 copper foil with surface reconstruction is obtained after winding.

[0058] Example 3

[0059] (1) The heavy-weight C11000 copper foil is unrolled for degreasing and oil removal. The degreasing agent used for degreasing is an alkaline degreasing agent, the treatment temperature is 50°C, the treatment time is 40s, and then acid is carried out. The pickling liquid is an 8.5% sulfuric acid aqueous solution, the acid time is 75s, and after water washing and drying, a fresh and clean surface is obtained;

[0060] (2) Using a heavy roll of C11000 copper foil as the working electrode, an Ag / AgCl electrode as the reference electrode, and a Pt electrode as the counter electrode, an electrochemical surface treatment was carried out in a surface treatment solution using a three-electrode system. The surface treatment solution mainly consisted of deionized water, magnesium formate, and a mixture of dimethylformamide and methyl acetate. The deionized water content was 5L, the polar solvent content was 10mL, and the formate content was 30g; the polar solvent was a mixture of dimethylformamide and methyl acetate, with dimethylformamide being 40% and methyl acetate being 60%. The pH of the surface treatment solution was 10.

[0061] (3) The surface treatment is carried out in four tanks, the first tank is an oxidation tank, the second tank is a reduction tank, the third tank is a BTA treatment tank, and the fourth tank is a cleaning and drying tank. The heavy roll C11000 copper foil passes through the oxidation tank, the reduction tank, the BTA treatment tank and the cleaning and drying tank in sequence. The oxidation tank adopts cyclic voltammetry for oxidation reaction, the test temperature is 40°C, the number of scanning circles is 4 circles, and the scanning time is 5 minutes; the reduction tank adopts constant potential deposition method for reduction reaction, the potential is -3V~3V, the scanning speed is 20mV / s, and the treatment time is 9 minutes; the BTA treatment tank performs BTA treatment on the copper material, the BTA treatment temperature is 60°C, the BTA content is 9%, and the treatment time is 60s; the copper foil is cleaned and dried in the cleaning and drying tank, and the heavy roll C11000 copper foil with surface reconstruction is obtained after winding.

[0062] Example 4

[0063] (1) The heavy C19400 copper strip is unrolled for degreasing and oil removal. The degreasing agent used for degreasing is an alkaline degreasing agent, the treatment temperature is 40°C, the treatment time is 45s, and then acid is carried out. The pickling liquid is a 9% sulfuric acid aqueous solution, the acid time is 70s, and after water washing and drying, a fresh and clean surface is obtained;

[0064] (2) A heavy-duty C19400 copper strip was used as the working electrode, a saturated calomel electrode was used as the reference electrode, and a graphite electrode was used as the counter electrode. Electrochemical surface treatment was carried out in a surface treatment solution using a three-electrode system. The surface treatment solution was mainly composed of deionized water, potassium formate, and a mixture of dimethylformamide and methyl acetate. The deionized water content was 3L, the polar solvent content was 6mL, and the formate content was 20g; the polar solvent was a mixture of dimethylformamide and methyl acetate, with dimethylformamide being 38% and methyl acetate being 62%. The pH of the surface treatment solution was 9.

[0065] (3) The surface treatment is carried out in four tanks, the first tank is an oxidation tank, the second tank is a reduction tank, the third tank is a BTA treatment tank, and the fourth tank is a cleaning and drying tank. The heavy C19400 copper strip passes through the oxidation tank, the reduction tank, the BTA treatment tank and the cleaning and drying tank in sequence. The oxidation tank uses cyclic voltammetry to carry out oxidation reaction, the test temperature is 25°C, the number of scans is 3, and the scan time is 4 minutes; the reduction tank uses constant potential deposition method to carry out reduction reaction, the potential is -4V~4V, the scanning speed is 50mV / s, and the treatment time is 10 minutes; the BTA treatment tank carries out BTA treatment on the copper material, the BTA treatment temperature is 45°C, the BTA content is 15%, and the treatment time is 56 seconds; the copper strip is cleaned and dried in the cleaning and drying tank, and the heavy C19400 copper strip with surface reconstruction is obtained after winding.

[0066] Example 5

[0067] (1) The heavy C18150 copper rod is unrolled for degreasing and oil removal. The degreasing agent used for degreasing is an alkaline degreasing agent, the treatment temperature is 45°C, the treatment time is 40s, and then acid is carried out. The pickling liquid is a 9.5% sulfuric acid aqueous solution, the acid time is 65s, and after water washing and drying, a fresh and clean surface is obtained;

[0068] (2) Using a heavy-duty C18150 copper rod as the working electrode, an Ag / AgCl electrode as the reference electrode, and a Pt electrode as the counter electrode, an electrochemical surface treatment was carried out in a surface treatment solution using a three-electrode system. The surface treatment solution mainly consisted of deionized water, sodium formate, and a mixture of dimethylformamide and methyl acetate. The deionized water content was 4 L, the polar solvent content was 8 mL, and the formate content was 25 g; the polar solvent was a mixture of dimethylformamide and methyl acetate, with dimethylformamide being 32% and methyl acetate being 68%. The pH of the surface treatment solution was 8.

[0069] (3) The surface treatment is carried out in four tanks, the first tank is an oxidation tank, the second tank is a reduction tank, the third tank is a BTA treatment tank, and the fourth tank is a cleaning and drying tank. The heavy C18150 copper rod passes through the oxidation tank, reduction tank, BTA treatment tank and cleaning and drying tank in sequence. The oxidation tank uses cyclic voltammetry to carry out oxidation reaction, the test temperature is 35°C, the number of scans is 5, and the scanning time is 6 minutes; the reduction tank uses constant potential deposition method to carry out reduction reaction, the potential is -3V~3V, the scanning speed is 100mV / s, and the treatment time is 8 minutes; the BTA treatment tank carries out BTA treatment on the copper material, the BTA treatment temperature is 55°C, the BTA content is 12%, and the treatment time is 58 seconds; the copper rod is cleaned and dried in the cleaning and drying tank, and the heavy C18150 copper rod with surface reconstruction is obtained after winding.

[0070] Example 6

[0071] (1) The heavy coil C36000 copper rod is unrolled for degreasing and oil removal. The degreasing agent selected for degreasing is an alkaline degreasing agent, the treatment temperature is 30°C, the treatment time is 50s, and then acid is carried out. The pickling liquid is an 11% sulfuric acid aqueous solution, the acid time is 50s, and after water washing and drying, a fresh and clean surface is obtained;

[0072] (2) A heavy-duty C36000 copper rod was used as the working electrode, a saturated calomel electrode was used as the reference electrode, and a graphite electrode was used as the counter electrode. Electrochemical surface treatment was carried out in a surface treatment solution using a three-electrode system. The surface treatment solution was mainly composed of deionized water, calcium formate, and a mixture of dimethylformamide and methyl acetate. The deionized water content was 2L, the polar solvent content was 5mL, and the formate content was 18g; the polar solvent was a mixture of dimethylformamide and methyl acetate, with dimethylformamide being 34% and methyl acetate being 66%. The pH of the surface treatment solution was 7.

[0073] (3) The surface treatment is carried out in four tanks, the first tank is an oxidation tank, the second tank is a reduction tank, the third tank is a BTA treatment tank, and the fourth tank is a cleaning and drying tank. The heavy C36000 copper rod passes through the oxidation tank, reduction tank, BTA treatment tank and cleaning and drying tank in sequence. The oxidation tank uses cyclic voltammetry to carry out oxidation reaction, the test temperature is 38°C, the number of scans is 8, and the scan time is 10min; the reduction tank uses constant potential deposition method to carry out reduction reaction, the potential is -4V~4V, the scanning speed is 60mV / s, and the treatment time is 7min; the BTA treatment tank carries out BTA treatment on the copper material, the BTA treatment temperature is 60°C, the BTA content is 13%, and the treatment time is 54s; the copper material is cleaned and dried in the cleaning and drying tank, and the heavy C36000 copper rod with surface reconstruction is obtained after winding.

[0074] Example 7

[0075] (1) The heavy C52100 copper strip is unrolled for degreasing and oil removal. The degreasing agent used for degreasing is an alkaline degreasing agent, the treatment temperature is 40°C, the treatment time is 60s, and then acid is carried out. The pickling liquid is a 12% sulfuric acid aqueous solution, the acid time is 40s, and after water washing and drying, a fresh and clean surface is obtained;

[0076] (2) A heavy-duty C52100 copper strip was used as the working electrode, a saturated calomel electrode was used as the reference electrode, and a graphite electrode was used as the counter electrode. Electrochemical surface treatment was carried out in a surface treatment solution using a three-electrode system. The surface treatment solution was mainly composed of deionized water, calcium formate, and a mixture of dimethylformamide and methyl acetate. The deionized water content was 1L, the polar solvent content was 9mL, and the formate content was 15g; the polar solvent was a mixture of dimethylformamide and methyl acetate, with dimethylformamide being 36% and methyl acetate being 64%. The pH of the surface treatment solution was 8.

[0077] (3) The surface treatment is carried out in four tanks, the first tank is an oxidation tank, the second tank is a reduction tank, the third tank is a BTA treatment tank, and the fourth tank is a cleaning and drying tank. The heavy C52100 copper strip passes through the oxidation tank, the reduction tank, the BTA treatment tank and the cleaning and drying tank in sequence. The oxidation tank uses cyclic voltammetry to carry out oxidation reaction, the test temperature is 28°C, the number of scans is 7, and the scan time is 9 minutes; the reduction tank uses constant potential deposition method to carry out reduction reaction, the potential is -3V~3V, the scanning speed is 70mV / s, and the treatment time is 4 minutes; the BTA treatment tank carries out BTA treatment on the copper material, the BTA treatment temperature is 40°C, the BTA content is 14%, and the treatment time is 50 seconds; the copper strip is cleaned and dried in the cleaning and drying tank, and the heavy C52100 copper strip with surface reconstruction is obtained after winding.

[0078] Example 8

[0079] (1) The heavy C70600 copper strip is unrolled for degreasing and oil removal. The degreasing agent used for degreasing is an alkaline degreasing agent, the treatment temperature is 50°C, the treatment time is 30s, and then acid is carried out. The pickling liquid is an 11.5% sulfuric acid aqueous solution, the acid time is 45s, and after water washing and drying, a fresh and clean surface is obtained;

[0080] (2) Using a heavy-duty C70600 copper strip as the working electrode, an Ag / AgCl electrode as the reference electrode, and a Pt electrode as the counter electrode, an electrochemical surface treatment was carried out in a surface treatment solution using a three-electrode system. The surface treatment solution mainly consisted of deionized water, sodium formate, and a mixture of dimethylformamide and methyl acetate. The deionized water content was 5 L, the polar solvent content was 8 mL, and the formate content was 25 g; the polar solvent was a mixture of dimethylformamide and methyl acetate, with dimethylformamide being 40% and methyl acetate being 60%. The pH of the surface treatment solution was 6.

[0081] (3) The surface treatment is carried out in four tanks, the first tank is an oxidation tank, the second tank is a reduction tank, the third tank is a BTA treatment tank, and the fourth tank is a cleaning and drying tank. The heavy C70600 copper strip passes through the oxidation tank, the reduction tank, the BTA treatment tank and the cleaning and drying tank in sequence. The oxidation tank uses cyclic voltammetry to carry out oxidation reaction, the test temperature is 34°C, the number of scans is 6, and the scan time is 8 minutes; the reduction tank uses constant potential deposition method to carry out reduction reaction, the potential is -5V~5V, the scanning speed is 5mV / s, and the treatment time is 5 minutes; the BTA treatment tank carries out BTA treatment on the copper material, the BTA treatment temperature is 50°C, the BTA content is 11%, and the treatment time is 45 seconds; the copper strip is cleaned and dried in the cleaning and drying tank, and the heavy C70600 copper strip with surface reconstruction is obtained after winding.

[0082] Example 9

[0083] The difference from Example 1 is that the pH of the surface treatment solution is 10, and finally a C10100 copper strip with a large coil weight and a reconstructed surface is obtained.

[0084] Example 10

[0085] The difference from Example 1 is that the pH of the surface treatment solution is 12, and finally a C10100 copper strip with a large coil weight and a reconstructed surface is obtained.

[0086] Embodiment 11

[0087] The difference from Example 1 is that the oxidation tank uses cyclic voltammetry to carry out oxidation reaction, the scanning number of circles is 8 circles, and finally a C10100 copper strip with a large coil weight and a surface reconstruction is obtained.

[0088] Example 12

[0089] The difference from Example 1 is that the oxidation tank uses cyclic voltammetry to carry out oxidation reaction, the scanning number of circles is 1 circle, and finally a C10100 copper strip with a large coil weight and a surface reconstruction is obtained.

[0090] Embodiment 13

[0091] The difference from Example 1 is that the oxidation tank uses cyclic voltammetry to carry out oxidation reaction, and the scanning time is 10 minutes, and finally a C10100 copper strip with a large coil weight and a surface reconstruction is obtained.

[0092] Embodiment 14

[0093] The difference from Example 1 is that the oxidation tank uses cyclic voltammetry to carry out oxidation reaction, and the scanning time is 2 minutes, and finally a C10100 copper strip with a large coil weight and a surface reconstruction is obtained.

[0094] Embodiment 15

[0095] The difference from Example 1 is that the reduction tank adopts a constant potential deposition method for reduction reaction, the potential is -5V to 5V, the scanning speed is 30mV / s, the processing time is 6min, and finally a surface reconstructed heavy-weight C10100 copper strip is obtained.

[0096] Example 16

[0097] The difference from Example 1 is that the reduction tank adopts a constant potential deposition method for reduction reaction, the potential is -1V to 1V, the scanning speed is 30mV / s, the processing time is 6min, and finally a surface reconstructed heavy-weight C10100 copper strip is obtained.

[0098] Embodiment 17

[0099] The difference from Example 1 is that the reduction tank adopts a constant potential deposition method to carry out the reduction reaction, and the scanning speed is 100 mV / s, and finally a C10100 copper strip with a large coil weight and a surface reconstruction is obtained.

[0100] Embodiment 18

[0101] The difference from Example 1 is that the reduction tank adopts a constant potential deposition method to carry out the reduction reaction, and the scanning speed is 150 mV / s, and finally a C10100 copper strip with a large coil weight and a surface reconstruction is obtained.

[0102] Embodiment 19

[0103] The difference from Example 1 is that the reduction tank adopts a constant potential deposition method to carry out the reduction reaction, and the scanning speed is 0.1 mV / s, and finally a C10100 copper strip with a large coil weight and a surface reconstruction is obtained.

[0104] Embodiment 20

[0105] The difference from Example 1 is that the dimethylformamide is 40% and the methyl acetate is 60%, and finally a C10100 copper strip with a large coil weight and a reconstructed surface is obtained.

[0106] Embodiment 21

[0107] The difference from Example 1 is that the dimethylformamide is 20% and the methyl acetate is 80%, and finally a C10100 copper strip with a large coil weight and a reconstructed surface is obtained.

[0108] Embodiment 22

[0109] The difference from Example 1 is that the content of deionized water is 1 L, the content of polar solvent is 5 mL, and the content of formate is 10 g, and finally a C10100 copper strip with a large roll weight and a surface reconstruction is obtained.

[0110] Embodiment 23

[0111] The difference from Example 1 is that the content of deionized water is 5 L, the content of polar solvent is 10 mL, and the content of formate is 30 g, and finally a C10100 copper strip with a large roll weight and a surface reconstruction is obtained.

[0112] Embodiment 24

[0113] The difference from Example 1 is that the content of deionized water is 6 L, the content of polar solvent is 4 mL, and the content of formate is 8 g, and finally a C10100 copper strip with a large roll weight and a surface reconstruction is obtained.

[0114] Embodiment 25

[0115] The difference from Example 1 is that the copper material is not subjected to BTA treatment, and a C10100 copper strip with a large coil weight and a reconstructed surface is obtained.

[0116] Comparative Example 1

[0117] (1) The heavy C10100 copper strip is unrolled for degreasing and oil removal. The degreasing agent used for degreasing is an alkaline degreasing agent, the treatment temperature is 20°C, the treatment time is 60s, and then acid is carried out. The pickling liquid is a 5% sulfuric acid aqueous solution, the acid time is 80s, and after water washing and drying, a fresh and clean surface is obtained;

[0118] (2) A heavy-duty C10100 copper strip was used as the working electrode, the Ag / AgCl electrode was used as the reference electrode, and the Pt electrode was used as the counter electrode. Electrochemical surface treatment was carried out in a surface treatment solution using a three-electrode system. The surface treatment solution was mainly composed of deionized water, potassium formate, and a mixture of dimethylformamide and methyl acetate. The deionized water content was 0.5 L, the polar solvent content was 2 mL, and the formate content was 10 g; the polar solvent was a mixture of dimethylformamide and methyl acetate, with dimethylformamide being 20% ​​and methyl acetate being 80%. The pH of the surface treatment solution was 12.

[0119] (3) The surface treatment is carried out in four tanks, the first tank is an oxidation tank, the second tank is a reduction tank, the third tank is a BTA treatment tank, and the fourth tank is a cleaning and drying tank. The heavy C10100 copper strip passes through the oxidation tank, the reduction tank, the BTA treatment tank and the cleaning and drying tank in sequence. The oxidation tank uses cyclic voltammetry to carry out oxidation reaction, the test temperature is 40°C, the number of scans is 1, and the scan time is 2 min; the reduction tank uses constant potential deposition method to carry out reduction reaction, the potential is -5V~5V, the scanning speed is 20mV / s, and the treatment time is 2 min; the BTA treatment tank carries out BTA treatment on the copper material, the BTA treatment temperature is 30°C, the BTA content is 5%, and the treatment time is 30s; the copper strip is cleaned and dried in the cleaning and drying tank, and the heavy C10100 copper strip with surface reconstruction is obtained after winding.

[0120] Comparative Example 2

[0121] (1) The heavy C19400 copper strip is unrolled for degreasing and oil removal. The degreasing agent used for degreasing is an alkaline degreasing agent, the treatment temperature is 60°C, the treatment time is 30s, and then acid is carried out. The pickling liquid is a 15% sulfuric acid aqueous solution, the acid time is 40s, and after water washing and drying, a fresh and clean surface is obtained;

[0122] (2) A heavy-duty C19400 copper strip was used as the working electrode, a saturated calomel electrode was used as the reference electrode, and a graphite electrode was used as the counter electrode. Electrochemical surface treatment was carried out in a surface treatment solution using a three-electrode system. The surface treatment solution was mainly composed of deionized water, sodium formate, and a mixture of dimethylformamide and methyl acetate. The deionized water content was 8 L, the polar solvent content was 15 mL, and the formate content was 30 g; the polar solvent was a mixture of dimethylformamide and methyl acetate, with dimethylformamide being 50% and methyl acetate being 50%. The pH of the surface treatment solution was 5.

[0123] (3) The surface treatment is carried out in four tanks, the first tank is an oxidation tank, the second tank is a reduction tank, the third tank is a BTA treatment tank, and the fourth tank is a cleaning and drying tank. The heavy C19400 copper strip passes through the oxidation tank, the reduction tank, the BTA treatment tank and the cleaning and drying tank in sequence. The oxidation tank uses cyclic voltammetry to carry out oxidation reaction, the test temperature is 20°C, the number of scans is 10, and the scanning time is 15 minutes; the reduction tank uses constant potential deposition method to carry out reduction reaction, the potential is -2V~2V, the scanning speed is 60mV / s, and the treatment time is 15 minutes; the BTA treatment tank carries out BTA treatment on the copper material, the BTA treatment temperature is 70°C, the BTA content is 20%, and the treatment time is 80s; the copper strip is cleaned and dried in the cleaning and drying tank, and the heavy C19400 copper strip with surface reconstruction is obtained after winding.

[0124] The CIE1976L*a*b* color space, or CIE LAB color space for short, is a uniform color space recommended by CIE (Commission Internationale de L'Eclairage). It is widely used in surface colors such as coatings, building materials, and metal colors because the color difference analysis of different surface colors is closest to the real visual effect. It consists of a vertical lightness axis L* and two chromaticity axes a* and b*. The L* axis is the lightness coordinate axis of the color. The L* value ranges from 0 to 100. It starts from the black at the bottom (L*=0) through the middle gray to the white at the top (L*=100), which is the total reflection color. The a* axis is the red-green axis. a*>0 indicates that the surface color of the object contains a red component, and a*<0 indicates that the surface color of the object contains a green component. The b* axis is the yellow-blue axis. b*>0 indicates that the surface color of the object contains a yellow component, and b*<0 indicates that the surface color of the object contains a blue component. The color difference value after the color of the object changes is represented by ΔE. When ΔE is less than 1, the color difference of the alloy surface is basically invisible, which is acceptable. When ΔE>1 or even greater, the human eye can distinguish the color difference, so it is unacceptable. The copper materials treated in the embodiment and the comparative example were immersed in 1M NaOH solution for 24 hours and tested using an X-Rite Ci7800 desktop spectrophotometer. The ΔE values ​​are shown in Table 1.

[0125] Crystal orientation analysis: The crystal orientation was analyzed by scanning electron microscopy (EBSD), and the surface treated copper material was magnified 45 times along the treatment direction for observation. The orientation of the sample was analyzed by OIM8.0 analysis software.

[0126] Corrosion rate analysis: The polarization curve of the sample after surface reconstruction was tested in 3.5% NaCl solution using a Swiss Metrohm electrochemical workstation, and the corrosion rate of the sample was measured through the polarization curve.

[0127] Table 1

[0128]

[0129]

[0130] From the above description, it can be seen that the above embodiments of the present invention achieve the following technical effects:

[0131] The surface antioxidant treatment method of the present application sequentially performs degreasing and oil removal treatment and acid cleaning treatment on the large coil heavy copper material, so that the oil stains, oxides, etc. on the surface of the large coil heavy copper material are removed, and the surface of the pretreated large coil heavy copper material is obtained. The continuous oxidation reaction of the pretreated large coil heavy copper material by the three-electrode system makes the surface of the pretreated large coil heavy copper material oxidized, that is, a Cu (110) structural layer is formed on its surface, and then the copper material after the oxidation reaction is subjected to a continuous reduction reaction to obtain the electrochemically treated large coil heavy copper material. In the process of the continuous reduction reaction, the Cu (110) structural layer combines with the formate ions in the formate, thereby forming a progressive valence structure, and the large coil heavy copper material after the electrochemical treatment sequentially forms a secondary layer of copper atoms with a valence of +1 and an outermost layer of copper atoms with a valence of +2 in the direction from the inside to the outside. Since the outermost +2-valent copper atoms of the large-volume heavy copper material have been combined with formate ions and present an oxidized state after electrochemical treatment, when external oxygen and other adsorbates combine with the outermost +2-valent copper atoms, it is necessary to overcome the adsorption of formate ions, and the oxidation kinetics of formate ions are relatively slow, so that the copper surface presents excellent anti-corrosion and anti-oxidation effects, and finally after further treatment by corrosion inhibitor surface treatment, the large-volume heavy copper material presents excellent protective effects. As can be seen from the above, the preparation process of the present invention can be used to carry out surface treatment of large-volume heavy copper materials, realize online continuous treatment of large-volume heavy copper materials, and is suitable for large-scale surface treatment of copper materials. In addition, the entire process of the above surface antioxidant treatment method can be carried out at room temperature, so that the above treatment process is more broad-spectrum.

[0132] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A surface anti-oxidation treatment method for a large coil of heavy copper material, characterized in that: The surface anti-oxidation treatment method comprises: Step S1, performing degreasing and oil removal treatment and acid cleaning treatment on the large coil heavy copper material in sequence to obtain the pretreated large coil heavy copper material; Step S2, using the pretreated large-volume heavy copper material as a working electrode, assembling the working electrode, the reference electrode, the counter electrode and the first electrolyte solution into a three-electrode system, passing the three-electrode system through an electrochemical oxidation treatment tank and an electrochemical reduction treatment tank in sequence, and the pretreated large-volume heavy copper material undergoes continuous oxidation reaction and continuous reduction reaction in the electrochemical oxidation treatment tank and the electrochemical reduction treatment tank in sequence to obtain an electrochemically treated large-volume heavy copper material; Step S3, washing and drying the electrochemically treated large coil heavy copper material in sequence to complete the surface anti-oxidation treatment of the large coil heavy copper material; Wherein, the electrolyte solution is a surface treatment solution, and the surface treatment solution comprises water, formate and a polar solvent; The pH value of the surface treatment liquid is 6-10.

2. The surface antioxidant treatment method according to claim 1, characterized in that: The continuous oxidation reaction is carried out by cyclic voltammetry, the temperature of the cyclic voltammetry is 20°C to 40°C, and / or the scanning number of the cyclic voltammetry is 2 to 8 circles, and / or the scanning time of the cyclic voltammetry is 2 minutes to 10 minutes.

3. The surface antioxidant treatment method according to claim 1 or 2, characterized in that: The continuous reduction reaction is carried out by a constant potential deposition method, the potential of the constant potential deposition method is -5V to 5V, and / or the scanning speed of the constant potential deposition method is 0.1mV / s to 100mV / s, and / or the processing time of the constant potential deposition method is 3min to 10min.

4. The surface antioxidant treatment method according to any one of claims 1 to 3, characterized in that: In the surface treatment liquid, the ratio of the volume of the water, the mass of the formate and the volume of the polar solvent is 1-5L:10-30g:5-10mL; and / or the water is deionized water; and / or the polar solvent is a mixture of dimethylformamide and methyl acetate, preferably the volume ratio of dimethylformamide to methyl acetate is 30-40:60-70; preferably, the formate is selected from any one or more of sodium formate, potassium formate, calcium formate and magnesium formate.

5. The surface antioxidant treatment method according to any one of claims 1 to 4, characterized in that: The large-volume heavy copper material is any one or more of a large-volume heavy copper strip, a large-volume heavy copper foil and a large-volume heavy copper rod; and / or, the models of the large-volume heavy copper material are independently selected from any one or more of C10100, C10200, C11000, C19400, C18150, C36000, C52100 and C70600.

6. The surface antioxidant treatment method according to any one of claims 1 to 5, characterized in that: The step S3 comprises: subjecting the electrochemically treated heavy copper coil to a corrosion inhibitor surface treatment and then performing the cleaning and drying, wherein the treatment liquid used for the corrosion inhibitor surface treatment is a benzotriazole solution, and the mass concentration of the benzotriazole solution is 8 to 15 wt %; and / or the temperature of the corrosion inhibitor surface treatment is 40 to 60° C.; and / or the time of the benzotriazole surface treatment is 40 to 60 s.

7. The surface antioxidant treatment method according to any one of claims 1 to 6, characterized in that: The reference electrode is a saturated calomel electrode or Ag / AgCl; and / or the counter electrode is a Pt electrode or a graphite electrode.

8. The surface antioxidant treatment method according to any one of claims 1 to 7, characterized in that: The degreasing and oil removal treatment is carried out using a degreasing agent, and / or the degreasing agent is an alkaline degreasing agent; and / or the temperature of the degreasing and oil removal treatment is 30-50° C.; and / or the time of the degreasing and oil removal treatment is 30-60 seconds.

9. The surface antioxidant treatment method according to any one of claims 1 to 8, characterized in that: The acid cleaning treatment is performed using a pickling solution, wherein the pickling solution is an aqueous sulfuric acid solution with a mass concentration of 8 to 12 wt %; and / or the acid cleaning treatment is performed for 40 to 80 seconds.

10. A large coil of heavy copper material after surface treatment, characterized in that: The surface treated heavy copper coil is obtained by the surface anti-oxidation treatment method according to any one of claims 1 to 9.

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