Aluminum copper welding method

Abstract

The present application relates to aluminium copper welding technical field, specifically a kind of aluminium copper welding method, steps are as follows: S1, cleaning treatment;S2, roughening treatment;S3, pre-alignment;S4, heating treatment;S5, coating adhesion material;S6, clamping and fixing;S7, melting welding wire welding;S8, check weld and repair;S9, polishing weld;S10, anti-oxidation treatment.The aluminium copper welding method of the present application removes oxidation layer on material by cleaning treatment and carries out roughening treatment, and after cleaning and roughening, anti-oxidation treatment is carried out, to avoid material oxidation during welding, improve the firmness of welding, roughening can roughen connecting surface, increase the connecting fastness of welding material, further improve the firmness of welding, increase the adhesion of aluminium and copper metal by adhesion material, increase the flatness of material connecting place after welding by weld repair and polishing, reduce the oxidation rate of metal after welding by anti-oxidation treatment, improve the durability of welding place.

Description

Technical Field

[0001] This invention relates to the field of aluminum-copper welding technology, specifically an aluminum-copper welding method. Background Technology

[0002] Copper-aluminum welding is the process of joining copper and aluminum materials together. Both copper and aluminum have good electrical conductivity. Forming a connection between aluminum and copper can reduce costs, lighten the weight of mechanical components, and leverage the advantages of each material. However, aluminum surfaces are easily oxidized, and the resulting oxide film is very strong and has high resistance, making mechanical connections unreliable. Therefore, welding methods are widely used in actual production to achieve the connection and improve the overall performance of copper and aluminum. Welding methods include wire welding, friction welding, and others.

[0003] Chinese patent discloses an aluminum-copper welding method (authorization announcement number CN112975027B). This patented technology includes the following steps: Step 1, cold spraying a pre-formed layer onto the welding area of ​​the aluminum weldment; the pre-formed layer includes flux and brazing filler metal, wherein the flux particles are coated onto the surface of the aluminum weldment by the bonding force between the brazing filler metal particles and the aluminum weldment; Step 2, a metal transition layer is pre-formed on the surface of the copper weldment; Step 3, welding the copper weldment and the aluminum weldment; Step 4, annealing and heat preservation. This invention uses brazing filler metal to coat the flux onto the surface of the aluminum weldment to form a pre-formed layer, improving welding strength and corrosion resistance. However, the above aluminum-copper welding process does not undergo anti-oxidation treatment, and the materials are easily oxidized during the welding process, affecting the weld's strength. Direct welding of the materials results in a relatively smooth contact surface, which is not conducive to the adhesion of the solder. Immediate use after welding without treatment leads to rapid oxidation of the solder and low durability. Therefore, those skilled in the art provide an aluminum-copper welding method to solve the problems mentioned in the background art. Summary of the Invention

[0004] The purpose of this invention is to provide an aluminum-copper welding method to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: an aluminum-copper welding method, comprising the following steps:

[0006] S1. Cleaning: Take out the aluminum and copper to be welded, clean the welding area, grind off the oxide layer on the outside of the aluminum or copper, remove the debris generated during grinding, and then apply turpentine to the metal to prevent the metal from oxidizing due to direct contact with air. Store for later use.

[0007] S2. Roughening treatment: Take out the cleaned aluminum and copper, roughen the contact surface of the weld by roughening, remove the debris generated by roughening, and then apply turpentine to the metal to prevent the metal from directly contacting the air and causing oxidation. Store for later use.

[0008] S3. Pre-alignment: Align the aluminum and copper welding surfaces and mark them. For aluminum and copper that cannot be aligned, make adjustments and re-align and mark them after adjustment. Save them for later use after they are in place.

[0009] S4. Heat treatment: Heat aluminum and copper separately, heating aluminum to 350℃-500℃ and copper to 700℃-850℃, and maintain the above heating temperatures.

[0010] S5. Applying adhesion promoter: Sprinkle the adhesion promoter onto the heated metal. The temperature of the metal melts the adhesion promoter, and the adhesion promoter coats the outside of the metal.

[0011] S6. Clip fixing: Press the aluminum and copper treated above together according to the pre-alignment marks, and fix them with clips;

[0012] S7. Melting welding wire welding: Use a flamethrower to heat the metal after clamping, place the welding wire at the joint, and melt and penetrate into the joint under the heat of the flamethrower. The melted welding wire cools and solidifies to complete the welding operation.

[0013] S8. Inspect and repair the weld: Remove the slag and check for holes in the weld. If there are holes, heat the weld to melt the weld material and repair the weld.

[0014] S9. Grinding the weld: Grind the weld to remove protruding metal and polish it. After polishing, heat the weld to evaporate the water on the polished metal and remove the clamped metal.

[0015] S10 Anti-oxidation treatment: Prepare an anti-oxidation adhesive, apply the adhesive evenly to the metal to isolate the metal from air, and complete the welding operation after the adhesive solidifies.

[0016] As a further aspect of the present invention: in S2, the roughening depth is between 0.05mm and 0.1mm, the roughening width is between 0.1mm and 0.5mm, and the roughening length is between 1mm and 2mm.

[0017] As a further embodiment of the present invention: the marking spacing in S3 is 0.5cm, and the marking depth is 0.5mm-1mm.

[0018] As a further embodiment of the present invention: the adhesive in S5 is composed of the following parts by weight: 10 parts rosin, 5 parts solder paste, 1 part o-hydroxybenzoic acid, 2 parts sodium dodecylbenzenesulfonate, 1 part nitrocellulose, and 1 part amine fluoride salt.

[0019] As a further aspect of the present invention: the flame emitted by the flamethrower in S7 is maintained between 1000℃ and 1200℃, and the calcination time is 20 seconds.

[0020] As a further embodiment of the present invention: the antioxidant liquid in S10 is composed of the following parts by weight: 15 parts copper oxide, 10 parts aluminum phosphate solution, 0.5 parts tea saponin, 0.8 parts sodium citrate, 0.1 parts dodecyl mercaptan, 0.1 parts 2-thiol benzoimidazole, 0.1 parts antioxidant BHT, 0.4 parts calcium lignosulfonate, 3 parts aminotrimethylphosphonic acid, and 0.1 parts boric acid.

[0021] As a further aspect of the present invention, the steps for preparing the adhesion promoter are as follows:

[0022] S501. Take out the rosin, o-hydroxybenzoic acid, sodium dodecylbenzenesulfonate, cellulose nitrate, and amine fluoride salt by weight and crush them separately.

[0023] S502. The pulverized materials are mixed with solder paste and ground to form a powder, thus completing the preparation of the adhesion promoter.

[0024] S503. Place the prepared adhesive additive into a glass container for storage and later use.

[0025] As a further aspect of the present invention, the preparation steps of the antioxidant adhesive are as follows:

[0026] S1001, take out copper oxide, tea saponin, sodium citrate, dodecyl mercaptan, 2-thiol benzoyl imidazole, and calcium lignosulfonate in measured portions, and mix them in a mixing tank;

[0027] S1002. Take out the aluminum phosphate solution, antioxidant BHT, aminotrimethylphosphonic acid, and boric acid in appropriate amounts and add them to the above materials for grinding. After grinding, an emulsion solution is formed and stored in a plastic bottle for later use.

[0028] Compared with the prior art, the beneficial effects of the present invention are:

[0029] 1. The aluminum-copper welding method of the present invention removes the oxide layer on the material through cleaning and roughening treatment. After cleaning and roughening, anti-oxidation treatment is performed to avoid oxidation of the material during welding, thereby improving the strength of the weld. Roughening can roughen the joint surface, increase the connection tightness of the weld material, and further improve the strength of the weld.

[0030] 2. By using adhesive additives to increase the adhesion of aluminum and copper metals during welding, by repairing and grinding the weld seam to increase the smoothness of the material joint after welding, and by using anti-oxidation treatment to reduce the oxidation rate of the metal after welding, the durability of the weld joint is improved. Attached Figure Description

[0031] Figure 1 This is a flowchart of an aluminum-copper welding method. Detailed Implementation

[0032] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] Example 1

[0034] In this embodiment of the invention, an aluminum-copper welding method comprises the following steps:

[0035] S1. Cleaning: Take out the aluminum and copper to be welded, clean the welding area, grind off the oxide layer on the outside of the aluminum or copper, remove the debris generated during grinding, and then apply turpentine to the metal to prevent the metal from oxidizing due to direct contact with air. Store for later use.

[0036] S2. Roughening treatment: Remove the cleaned aluminum and copper, roughen the contact surface of the weld by roughening, remove the debris generated by roughening, and then apply turpentine to the metal to prevent the metal from oxidizing due to direct contact with air. Store for later use. The roughening depth is between 0.05mm and 0.1mm, the roughening width is between 0.1mm and 0.5mm, and the roughening length is between 1mm and 2mm.

[0037] S3. Pre-alignment: Align the aluminum and copper welding surfaces and mark them. For aluminum and copper that cannot be aligned, repair them and re-align them and mark them. Save them for later use after they are suitable. The mark spacing is 0.5cm and the mark depth is 0.5mm-1mm.

[0038] S4. Heat treatment: Heat aluminum and copper separately, heating aluminum to 350°C and copper to 700°C, and maintain the above heating temperatures.

[0039] S5. Applying adhesion promoter: Sprinkle the adhesion promoter onto the heated metal. The temperature of the metal melts the adhesion promoter, and the adhesion promoter coats the outside of the metal.

[0040] S6. Clip fixing: Press the aluminum and copper treated above together according to the pre-alignment marks, and fix them with clips;

[0041] S7. Melting welding wire welding: Use a flamethrower to heat the metal after clamping, place the welding wire at the joint, and melt and penetrate into the joint under the heat of the flamethrower. The melted welding wire cools and solidifies to complete the welding operation. The flame from the flamethrower is maintained between 1000℃ and 1200℃, and the heating time is 20 seconds.

[0042] S8. Inspect and repair the weld: Remove the slag and check for holes in the weld. If there are holes, heat the weld to melt the weld material and repair the weld.

[0043] S9. Grinding the weld: Grind the weld to remove protruding metal and polish it. After polishing, heat the weld to evaporate the water on the polished metal and remove the clamped metal.

[0044] S10 Anti-oxidation treatment: Prepare an anti-oxidation adhesive, apply the adhesive evenly to the metal to isolate the metal from air, and complete the welding operation after the adhesive solidifies.

[0045] Example 2

[0046] In this embodiment of the invention, an aluminum-copper welding method comprises the following steps:

[0047] S1. Cleaning: Take out the aluminum and copper to be welded, clean the welding area, grind off the oxide layer on the outside of the aluminum or copper, remove the debris generated during grinding, and then apply turpentine to the metal to prevent the metal from oxidizing due to direct contact with air. Store for later use.

[0048] S2. Roughening treatment: Remove the cleaned aluminum and copper, roughen the contact surface of the weld by roughening, remove the debris generated by roughening, and then apply turpentine to the metal to prevent the metal from oxidizing due to direct contact with air. Store for later use. The roughening depth is between 0.05mm and 0.1mm, the roughening width is between 0.1mm and 0.5mm, and the roughening length is between 1mm and 2mm.

[0049] S3. Pre-alignment: Align the aluminum and copper welding surfaces and mark them. For aluminum and copper that cannot be aligned, repair them and re-align them and mark them. Save them for later use after they are suitable. The mark spacing is 0.5cm and the mark depth is 0.5mm-1mm.

[0050] S4. Heat treatment: Heat aluminum and copper separately, heating aluminum to 400°C and copper to 750°C, and maintain the above heating temperatures.

[0051] S5. Applying adhesion promoter: Sprinkle the adhesion promoter onto the heated metal. The temperature of the metal melts the adhesion promoter, and the adhesion promoter coats the outside of the metal.

[0052] S6. Clip fixing: Press the aluminum and copper treated above together according to the pre-alignment marks, and fix them with clips;

[0053] S7. Melting welding wire welding: Use a flamethrower to heat the metal after clamping, place the welding wire at the joint, and melt and penetrate into the joint under the heat of the flamethrower. The melted welding wire cools and solidifies to complete the welding operation. The flame from the flamethrower is maintained between 1000℃ and 1200℃, and the heating time is 20 seconds.

[0054] S8. Inspect and repair the weld: Remove the slag and check for holes in the weld. If there are holes, heat the weld to melt the weld material and repair the weld.

[0055] S9. Grinding the weld: Grind the weld to remove protruding metal and polish it. After polishing, heat the weld to evaporate the water on the polished metal and remove the clamped metal.

[0056] S10 Anti-oxidation treatment: Prepare an anti-oxidation adhesive, apply the adhesive evenly to the metal to isolate the metal from air, and complete the welding operation after the adhesive solidifies.

[0057] Example 3

[0058] In this embodiment of the invention, an aluminum-copper welding method comprises the following steps:

[0059] S1. Cleaning: Take out the aluminum and copper to be welded, clean the welding area, grind off the oxide layer on the outside of the aluminum or copper, remove the debris generated during grinding, and then apply turpentine to the metal to prevent the metal from oxidizing due to direct contact with air. Store for later use.

[0060] S2. Roughening treatment: Remove the cleaned aluminum and copper, roughen the contact surface of the weld by roughening, remove the debris generated by roughening, and then apply turpentine to the metal to prevent the metal from oxidizing due to direct contact with air. Store for later use. The roughening depth is between 0.05mm and 0.1mm, the roughening width is between 0.1mm and 0.5mm, and the roughening length is between 1mm and 2mm.

[0061] S3. Pre-alignment: Align the aluminum and copper welding surfaces and mark them. For aluminum and copper that cannot be aligned, repair them and re-align them and mark them. Save them for later use after they are suitable. The mark spacing is 0.5cm and the mark depth is 0.5mm-1mm.

[0062] S4. Heat treatment: Heat aluminum and copper separately, heating aluminum to 500°C and copper to 850°C, and maintain the above heating temperatures.

[0063] S5. Applying adhesion promoter: Sprinkle the adhesion promoter onto the heated metal. The temperature of the metal melts the adhesion promoter, and the adhesion promoter coats the outside of the metal.

[0064] S6. Clip fixing: Press the aluminum and copper treated above together according to the pre-alignment marks, and fix them with clips;

[0065] S7. Melting welding wire welding: Use a flamethrower to heat the metal after clamping, place the welding wire at the joint, and melt and penetrate into the joint under the heat of the flamethrower. The melted welding wire cools and solidifies to complete the welding operation. The flame from the flamethrower is maintained between 1000℃ and 1200℃, and the heating time is 20 seconds.

[0066] S8. Inspect and repair the weld: Remove the slag and check for holes in the weld. If there are holes, heat the weld to melt the weld material and repair the weld.

[0067] S9. Grinding the weld: Grind the weld to remove protruding metal and polish it. After polishing, heat the weld to evaporate the water on the polished metal and remove the clamped metal.

[0068] S10 Anti-oxidation treatment: Prepare an anti-oxidation adhesive, apply the adhesive evenly to the metal to isolate the metal from air, and complete the welding operation after the adhesive solidifies.

[0069] In Examples 1, 2, and 3, the adhesive additives and antioxidant adhesives all adopted the following formulations and methods.

[0070] The adhesion promoter consists of the following parts by weight: 10 parts rosin, 5 parts solder paste, 1 part o-hydroxybenzoic acid, 2 parts sodium dodecylbenzenesulfonate, 1 part cellulose nitrate, and 1 part amine fluoride salt. The preparation steps for the adhesion promoter are as follows:

[0071] S501. Take out the rosin, o-hydroxybenzoic acid, sodium dodecylbenzenesulfonate, cellulose nitrate, and amine fluoride salt by weight and crush them separately.

[0072] S502. The pulverized materials are mixed with solder paste and ground to form a powder, thus completing the preparation of the adhesion promoter.

[0073] S503. Place the prepared adhesive additive into a glass container for storage and later use.

[0074] The antioxidant adhesive consists of the following parts by weight: 15 parts copper oxide, 10 parts aluminum phosphate solution, 0.5 parts tea saponin, 0.8 parts sodium citrate, 0.1 parts dodecyl mercaptan, 0.1 parts 2-thiol benzoyl imidazole, 0.1 parts antioxidant BHT, 0.4 parts calcium lignosulfonate, 3 parts aminotrimethylphosphonic acid, and 0.1 parts boric acid. The preparation steps of the antioxidant adhesive are as follows:

[0075] S1001, take out copper oxide, tea saponin, sodium citrate, dodecyl mercaptan, 2-thiol benzoyl imidazole, and calcium lignosulfonate in measured portions, and mix them in a mixing tank;

[0076] S1002. Take out the aluminum phosphate solution, antioxidant BHT, aminotrimethylphosphonic acid, and boric acid in appropriate amounts and add them to the above materials for grinding. After grinding, an emulsion solution is formed and stored in a plastic bottle for later use.

[0077] To better illustrate the technical effects of the present invention, the following experiments are conducted:

[0078] Using the aluminum-copper welding method disclosed in CN112975027B as a comparative example, Embodiment 1, Embodiment 2, and Embodiment 3 are derived based on the content of this invention.

[0079] Based on experimental testing, parameter comparisons were performed, and the comparison data are as follows:

[0080] project Joint shear strength / MPa Welding temperature / ℃ Tensile strength after salt spray corrosion / MPa Antioxidant time / s Example 1 89MPa 482℃ 81MPa 43800S-52102S Example 2 93MPa 489℃ 84MPa 43800S-52102S Example 3 95MPa 501℃ 85MPa 43800S-52102S Comparative Example 1 85MPa 510℃ 76MPa 21280S-32510S

[0081] The experimental data above show that, according to the data in the table above, the shear strength of the joints in Examples 1, 2, and 3 is higher than that in Comparative Example 1; the tensile strength after salt spray corrosion in Examples 1, 2, and 3 is higher than that in Comparative Example 1; and the oxidation resistance time in Examples 1, 2, and 3 is longer than that in Comparative Example 1. It can be seen that the welding strength in Examples 1, 2, and 3 is higher than that in Comparative Example 1. The welding method in the examples is superior to that in the comparative example, exhibiting higher strength and longer durability.

[0082] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0083] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A method for welding aluminum and copper, characterized in that, The steps are as follows: S1. Cleaning: Take out the aluminum and copper to be welded, clean the welding area, grind off the oxide layer on the outside of the aluminum or copper, remove the debris generated during grinding, and then apply turpentine to the metal to prevent the metal from oxidizing due to direct contact with air. Store for later use. S2. Roughening treatment: Take out the cleaned aluminum and copper, roughen the contact surface of the weld by roughening, remove the debris generated by roughening, and then apply turpentine to the metal to prevent the metal from directly contacting the air and causing oxidation. Store for later use. S3. Pre-alignment: Align the aluminum and copper welding surfaces and mark them. For aluminum and copper that cannot be aligned, repair them and then pre-align and mark them again. Save the marked parts for later use. S4. Heat treatment: Heat aluminum and copper separately, heating aluminum to 350℃-500℃ and copper to 700℃-850℃, and maintain the above heating temperatures. S5. Applying adhesion promoter: Sprinkle the adhesion promoter onto the heated metal. The temperature of the metal melts the adhesion promoter, and the adhesion promoter coats the outside of the metal. S6. Clip fixing: Press the aluminum and copper treated above together according to the pre-alignment marks, and fix them with clips; S7. Melting welding wire welding: Use a flamethrower to heat the metal after clamping, place the welding wire at the joint, and the welding wire melts and penetrates into the joint under the heat of the flamethrower. The melted welding wire cools and solidifies to complete the welding operation. S8. Inspect and repair the weld: Remove the slag and check for holes in the weld. If there are holes, heat the weld to melt the weld material and repair the weld. S9. Grinding the weld: Grind the weld to remove the protruding metal and perform a polishing operation. After polishing, heat the weld to evaporate the liquid on the polished metal and remove the clamped metal. S10 Anti-oxidation treatment: Prepare an anti-oxidation adhesive, apply the adhesive evenly to the metal to isolate the metal from air, and complete the welding operation after the adhesive solidifies.

2. The aluminum-copper welding method according to claim 1, characterized in that, In S2, the roughening depth is between 0.05mm and 0.1mm, the roughening width is between 0.1mm and 0.5mm, and the roughening length is between 1mm and 2mm.

3. The aluminum-copper welding method according to claim 1, characterized in that, The marking spacing in S3 is 0.5cm, and the marking depth is 0.5mm-1mm.

4. The aluminum-copper welding method according to claim 1, characterized in that, The adhesive additive in S5 consists of the following parts by weight: 10 parts rosin, 5 parts solder paste, 1 part o-hydroxybenzoic acid, 2 parts sodium dodecylbenzenesulfonate, 1 part nitrocellulose, and 1 part amine fluoride salt.

5. The aluminum-copper welding method according to claim 1, characterized in that, The flame emitted by the flamethrower in S7 is maintained between 1000℃ and 1200℃, and the calcination time is 20 seconds.

6. The aluminum-copper welding method according to claim 1, characterized in that, The antioxidant adhesive in S10 is composed of the following parts by weight: 15 parts copper oxide, 10 parts aluminum phosphate solution, 0.5 parts tea saponin, 0.8 parts sodium citrate, 0.1 parts dodecyl mercaptan, 0.1 parts 2-thiol benzoimidazole, 0.1 parts antioxidant BHT, 0.4 parts calcium lignosulfonate, 3 parts aminotrimethylphosphonic acid, and 0.1 parts boric acid.

7. The aluminum-copper welding method according to claim 4, characterized in that, The steps for preparing the adhesion promoter are as follows: S501. Take out the rosin, o-hydroxybenzoic acid, sodium dodecylbenzenesulfonate, cellulose nitrate, and amine fluoride salt by weight and crush them separately. S502. The pulverized materials are mixed with solder paste and ground to form a powder, thus completing the preparation of the adhesion promoter. S503. Place the prepared adhesive additive into a glass container for storage and later use.

8. The aluminum-copper welding method according to claim 6, characterized in that, The preparation steps of the antioxidant adhesive are as follows: S1001. Take out copper oxide, tea saponin, sodium citrate, dodecyl mercaptan, 2-thiol benzoyl imidazole, and calcium lignin sulfonate in appropriate amounts and mix them in a mixing tank. S1002. Take out the aluminum phosphate solution, antioxidant BHT, aminotrimethylphosphonic acid, and boric acid in appropriate amounts and add them to the above materials for grinding. After grinding, an emulsion solution is formed and stored in a plastic bottle for later use.

Images