Metal plate surface texturing treatment method based on foam metal
By using foamed metal as the cathode and electrolyzing it with an aluminum alloy plate, and taking advantage of the non-uniform electric field distribution caused by its porosity, a large Sa value and uniform roughening effect on the aluminum alloy surface were achieved, solving the problem of low and non-uniform Sa value in the prior art.
Patent Information
- Application Number
- CN202511167002.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-20
- Publication Date
- 2025-11-21
AI Technical Summary
Existing electrolytic methods for texturing aluminum alloy surfaces result in low Sa values and uneven texturing effects, leading to inconsistent surface microstructures and affecting performance.
Foamed metal is used as the cathode, and the metal plate to be texturized is used as the anode. An electrolytic reaction is carried out in an electrolyte. The non-uniform electric field distribution caused by the porosity of the foamed metal is utilized to achieve a significant texturizing effect.
A larger Sa value and obvious uniformity of texturing effect were obtained, which solved the problem of low and uneven Sa value in the prior art and improved the roughness and uniformity of the metal plate surface.
Smart Images
Figure CN120989698A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a method for roughening the surface of a metal plate based on foamed metal. Background Technology
[0002] Workpieces made of metallic materials, in addition to possessing good strength, hardness, rigidity, wear resistance, and corrosion resistance, also require excellent flowability, coatability, and special properties such as light absorption and wave absorption in certain specific scenarios. By roughening the surface of metallic workpieces, these performance requirements can be better met. A roughened surface refers to a working surface exhibiting uniformly distributed, regularly arranged, and densely packed micro-pits. Ideally, a roughened metal surface should not only have a high Sa value but also possess as many pits as possible.
[0003] There are existing reports on using electrolytic methods to roughen the surface of aluminum alloys. However, while existing electrolytic methods can induce a certain degree of pitting corrosion on the aluminum alloy surface, achieving the initial roughening purpose, this method has the following problems: the Sa value of the roughened aluminum alloy surface is low, and the roughening effect exhibits obvious non-uniformity. On the roughened aluminum alloy surface, the diameter of the pits varies greatly, with some pits being larger than others, showing a significant difference. This not only leads to inconsistent surface micromorphology but may also affect the performance of the aluminum alloy workpiece in actual use. Summary of the Invention
[0004] Purpose of the invention: The purpose of this invention is to provide a method for roughening the surface of a metal plate with a large Sa value.
[0005] Technical solution: The method for surface texturing of a metal plate based on foamed metal described in this invention specifically involves: placing foamed metal and the metal plate to be texturized opposite each other in an electrolyte, using the foamed metal as the cathode and the metal plate to be texturized as the anode, and connecting them to the negative and anode terminals of an external power supply, respectively; wherein the side of the metal plate to be texturized is positioned opposite the foamed metal; starting the power supply to perform an electrolytic reaction, and after the reaction, a surface-textured metal plate is obtained.
[0006] The foamed metal is aluminum foam; the porosity of the aluminum foam is 60%, and the pore size is 0.1-5 mm, preferably 5 mm.
[0007] The electrolyte is a neutral salt solution, such as sodium chloride solution or sodium nitrate solution, and the mass concentration of the electrolyte is 1-10%, preferably 10%.
[0008] The vertical distance (processing gap) between the foamed metal and the metal plate to be roughened is 0.1 to 1 mm, preferably 1 mm.
[0009] During the electrolysis process, a constant current method is used, with a current of 5 to 9 A, preferably 9 A.
[0010] The inherent porosity of foamed metal surfaces results in extreme surface unevenness, leading to an uneven electric field distribution and a significant roughening effect. Due to the numerous pores in the foamed metal, during the roughening process, the porous regions create a relatively sparse, weak electric field area on the metal surface, while the skeletal regions create a relatively dense, strong electric field area. The weak electric field areas on the metal surface will induce relatively weak electrochemical corrosion during processing, while the strong electric field areas will induce relatively strong electrochemical corrosion. This difference in corrosion effects results in uneven corrosion on the metal surface, causing a rapid increase in surface roughness and achieving a fast roughening effect.
[0011] Beneficial effects: The method of the present invention utilizes the extreme unevenness of the surface caused by the pores of the foam metal surface, so that the surface of the metal plate being treated is in a state of uneven electric field distribution, thereby obtaining a large Sa value and achieving a significant texturing effect. It effectively solves the problems of low Sa value of aluminum alloy texturing surface and obvious unevenness of texturing effect in the existing electrolysis method. Attached Figure Description
[0012] Figure 1 This is a schematic diagram of the device structure used in the method of the present invention;
[0013] Figure 2 This is a schematic diagram of the current density during the texturing process of a metal plate surface.
[0014] Figure 3 This is a schematic diagram of the anodic corrosion thickness after roughening the surface of a metal plate.
[0015] Figure 4 This is a schematic diagram of the electrolyte potential after the surface of a metal plate has undergone a texturing treatment.
[0016] Figure 5 This is a microscopic morphology image of the metal plate after treatment in Example 1;
[0017] Figure 6 The image shows the microstructure of the metal plate after treatment in Example 2.
[0018] Figure 7 This is a microscopic morphology image of the metal plate after treatment in Example 3;
[0019] Figure 8 This is a microscopic morphology image of the metal plate after treatment in Example 4;
[0020] Figure 9 This is a microscopic morphology image of the metal plate after treatment in Example 5;
[0021] Figure 10 This is a microscopic morphology image of the metal plate after treatment in Example 6;
[0022] Figure 11 This is a microscopic morphology image of the metal plate after treatment in Example 7;
[0023] Figure 12 This is a microscopic morphology image of the metal plate after treatment in Example 8;
[0024] Figure 13 The image shows the microstructure of the metal plate after treatment in Comparative Example 1.
[0025] Figure 14 This is a microscopic morphology image of the metal plate after treatment in Comparative Example 2. Detailed Implementation
[0026] like Figure 1 As shown, the present invention relates to a metal plate surface roughening treatment device based on foamed metal, comprising an electrolytic cell 6, with foamed metal 1 as the tool cathode, fixed in the electrolytic cell 6 through pin holes I3 (pin holes need to be reserved at both ends of the foamed metal for fixing the tool cathode and for energizing), and a metal plate 2 to be surface roughened as the workpiece anode, fixed in the electrolytic cell 6 through pin holes II4 (pin holes need to be reserved on the surface of the metal plate for fixing the workpiece anode and for energizing). A neutral salt solution 5 is added to the electrolytic cell 6, immersing the metal plate 2 and the foamed metal 1 in the salt solution. Using conductive clamps 8 and wires 9, the foamed metal 1 and the metal plate 2 are connected to the negative and positive terminals of a power supply 7, respectively. The foamed metal 1 includes a foamed metal skeleton region 11 and a foamed metal pore region 12. Before roughening the metal plate 2, the oxide film and grease on the surface of the metal plate 2 need to be removed with water and alcohol, and then dried to obtain the workpiece anode required by the present invention.
[0027] Example 1
[0028] The surface roughening treatment method for metal plates based on the above-mentioned device is as follows:
[0029] The initial side length a of the anode workpiece (with square upper and lower surfaces) is 45cm; the initial side length b of the cathode tool (with square upper and lower surfaces) is 45cm; the anode workpiece is aluminum alloy, and the cathode workpiece is aluminum foam; the porosity of the aluminum foam is 60%, the pore size is 5mm, the electrolyte is a 10% sodium nitrate solution, the electrolytic processing temperature is 37℃, and the processing gap between the aluminum foam and the aluminum alloy is 1mm; during the electrolysis process, the current between the anode aluminum alloy plate and the cathode aluminum foam is 9A, the processing time is 90s, and a surface-textured aluminum alloy is obtained.
[0030] Figures 5-14 In this context, Sa is the arithmetic mean deviation, reflecting the average level of surface roughness; a higher value indicates a rougher surface. Sku is kurtosis, reflecting the steepness and gentleness of surface peaks and valleys; more than 3 peaks indicate sharper surfaces, while fewer than 3 peaks indicate gentler surfaces. Sp is the maximum peak height, reflecting the highest local protrusions on the surface. Sq is the root mean square deviation, sensitive to surface micro-undulations and often used to assist Sa values in assessing surface roughness. Ssk is skewness, a measure of the symmetry of surface profile distribution; positive skewness indicates more peaks and shallower valleys, while negative skewness indicates more valleys and shallower peaks. Sv is the maximum valley depth, reflecting the deepest local depressions on the surface. Sz is the maximum height, reflecting the maximum amplitude of overall surface undulations.
[0031] like Figure 5 After treatment, the Sa value of the surface of the anodic aluminum alloy plate is 6.422 μm and the Sq value is 8.269 μm.
[0032] like Figure 2 As shown in the blue area, the porous region 12 of the foamed metal forms a relatively loose, weak electric field region on the surface of the metal plate 2, where the electric field lines 10 are sparse. Figure 2 As shown in the red area, the foam metal skeleton region 11 forms a relatively dense, strong electric field region with electric field lines 10 on the surface of the metal plate 2; as Figure 3 As shown in the blue area, the weak electric field region on the surface of metal plate 2 will form a relatively weak electrochemical corrosion effect during the processing, such as... Figure 3 As shown in the red area, the strong electric field area on the surface of metal plate 2 will form a relatively strong electrochemical corrosion effect during the processing. The difference in corrosion effect between the two causes uneven corrosion on the surface of metal plate 2, resulting in a sharp increase in the surface roughness of metal plate 2, thereby achieving a rapid roughening effect.
[0033] Example 2
[0034] The surface roughening treatment method for metal plates based on the above-mentioned device is as follows:
[0035] The initial side length a of the anode workpiece (square on both the upper and lower surfaces) is 45cm; the initial side length b of the cathode tool (square on both the upper and lower surfaces) is 45cm; the anode workpiece is aluminum alloy, and the cathode workpiece is aluminum foam; the porosity of the aluminum foam is 60%, the pore size is 5mm, the electrolyte is a 10% sodium chloride solution, the electrolytic processing temperature is 37℃, and the processing gap between the aluminum foam and the aluminum alloy is 1mm; during the electrolysis process, the current between the anode aluminum metal plate and the cathode aluminum foam is 9A, the processing time is 60s, and a surface roughened aluminum alloy is obtained.
[0036] like Figure 6 As shown, the Sa value of the treated anode aluminum alloy plate is 8.499 μm and the Sq value is 10.484 μm.
[0037] Example 3
[0038] The surface roughening treatment method for metal plates based on the above-mentioned device is as follows:
[0039] The initial side length a of the anode workpiece (with square upper and lower surfaces) is 45cm; the initial side length b of the cathode tool (with square upper and lower surfaces) is 45cm; the anode workpiece is aluminum alloy, and the cathode workpiece is aluminum foam; the porosity of the aluminum foam is 60%, the pore size is 5mm, the electrolyte is a 10% sodium chloride solution, the electrolytic processing temperature is 37℃, and the processing gap between the aluminum foam and the aluminum alloy is 1mm; during the electrolysis process, the current between the anode aluminum metal plate and the cathode aluminum foam is 9A, the processing time is 90s, and a surface roughened aluminum alloy is obtained.
[0040] like Figure 7 As shown, the Sa value of the treated anode aluminum alloy plate is 8.964 μm and the Sq value is 11.206 μm.
[0041] The aluminum alloy surface treated by this invention was photographed in different areas using a white light interferometer. It was found that the Sa and Sq values of the treated areas were less than 0.3 μm apart, indicating that the texturing effect of this invention has obvious uniformity.
[0042] Example 4
[0043] The surface roughening treatment method for metal plates based on the above-mentioned device is as follows:
[0044] The initial side length a of the anode workpiece (with square upper and lower surfaces) is 45cm; the initial side length b of the cathode tool (with square upper and lower surfaces) is 45cm; the anode workpiece is aluminum alloy, and the cathode workpiece is aluminum foam; the porosity of the aluminum foam is 60%, the pore size is 5mm, the electrolyte is a 10% sodium chloride solution, the electrolytic processing temperature is 37℃, and the processing gap between the aluminum foam and the aluminum alloy is 1mm; during the electrolysis process, the current between the anode aluminum metal plate and the cathode aluminum foam is 9A, the processing time is 120s, and a surface roughened aluminum alloy is obtained.
[0045] like Figure 8 As shown, the Sa value of the treated anode aluminum alloy plate is 5.221 μm and the Sq value is 6.741 μm.
[0046] Example 5
[0047] The surface roughening treatment method for metal plates based on the above-mentioned device is as follows:
[0048] The initial side length a of the anode workpiece (with square upper and lower surfaces) is 45cm; the initial side length b of the cathode tool (with square upper and lower surfaces) is 45cm; the anode workpiece is aluminum alloy, and the cathode workpiece is aluminum foam; the porosity of the aluminum foam is 60%, the pore size is 0.1mm, the electrolyte is a 10% sodium chloride solution, the electrolytic processing temperature is 37℃, and the processing gap between the aluminum foam and the aluminum alloy is 1mm; during the electrolysis process, the current between the anode aluminum metal plate and the cathode aluminum foam is 9A, the processing time is 90s, and a surface roughened aluminum alloy is obtained.
[0049] like Figure 9 As shown, the Sa value of the treated anode aluminum alloy plate is 6.742 μm and the Sq value is 8.177 μm.
[0050] Example 6
[0051] The surface roughening treatment method for metal plates based on the above-mentioned device is as follows:
[0052] The initial side length a of the anode workpiece (with square upper and lower surfaces) is 45cm; the initial side length b of the cathode tool (with square upper and lower surfaces) is 45cm; the anode workpiece is aluminum alloy, and the cathode workpiece is aluminum foam; the porosity of the aluminum foam is 60%, the pore size is 1mm, the electrolyte is a 10% sodium chloride solution, the electrolytic processing temperature is 37℃, and the processing gap between the aluminum foam and the aluminum alloy is 1mm; during the electrolysis process, the current between the anode aluminum metal plate and the cathode aluminum foam is 9A, the processing time is 120s, and a surface roughened aluminum alloy is obtained.
[0053] like Figure 10As shown, the Sa value of the treated anode aluminum alloy plate is 7.543 μm and the Sq value is 9.249 μm.
[0054] Example 7
[0055] The surface roughening treatment method for metal plates based on the above-mentioned device is as follows:
[0056] The initial side length a of the anode workpiece (with square upper and lower surfaces) is 45cm; the initial side length b of the cathode tool (with square upper and lower surfaces) is 45cm; the anode workpiece is aluminum alloy, and the cathode workpiece is aluminum foam; the porosity of the aluminum foam is 60%, the pore size is 0.1mm, the electrolyte is a 5% sodium chloride solution, the electrolytic processing temperature is 37℃, and the processing gap between the aluminum foam and the aluminum alloy is 1mm; during the electrolysis process, the current between the anode aluminum metal plate and the cathode aluminum foam is 9A, the processing time is 90s, and a surface roughened aluminum alloy is obtained.
[0057] like Figure 11 As shown, the Sa value of the treated anode aluminum alloy plate is 7.666 μm and the Sq value is 8.942 μm.
[0058] Example 8
[0059] The surface roughening treatment method for metal plates based on the above-mentioned device is as follows:
[0060] The initial side length a of the anode workpiece (with square upper and lower surfaces) is 45cm; the initial side length b of the cathode tool (with square upper and lower surfaces) is 45cm; the anode workpiece is aluminum alloy, and the cathode workpiece is aluminum foam; the porosity of the aluminum foam is 60%, the pore size is 0.1mm, the electrolyte is a 1% sodium chloride solution, the electrolytic processing temperature is 37℃, and the processing gap between the aluminum foam and the aluminum alloy is 1mm; during the electrolysis process, the current between the anode aluminum metal plate and the cathode aluminum foam is 9A, the processing time is 90s, and a surface roughened aluminum alloy is obtained.
[0061] like Figure 12 As shown, the Sa value of the treated anode aluminum alloy plate is 3.544 μm and the Sq value is 4.509 μm.
[0062] Comparative Example 1
[0063] A method for roughening the surface of a metal plate, specifically comprising:
[0064] The initial side length a of the anode workpiece (with square upper and lower surfaces) is 45cm; the initial side length b of the cathode tool (with square upper and lower surfaces) is 45cm; the anode workpiece is made of aluminum alloy, and the cathode workpiece is made of aluminum alloy blank; the electrolyte is a 10% sodium nitrate solution, the electrolytic processing temperature is 37℃, and the processing gap between the copper plate and the aluminum alloy is 1mm; during the electrolysis process, the current between the anode aluminum blank and the cathode foam aluminum is 9A, and the processing time is 90s, resulting in a surface-textured aluminum alloy.
[0065] like Figure 13 As shown, the Sa value of the treated anode aluminum alloy plate is 3.770 μm and the Sq value is 4.819 μm.
[0066] Comparative Example 2
[0067] A method for roughening the surface of a metal plate, specifically comprising:
[0068] The initial side length a of the anode workpiece (with square upper and lower surfaces) is 45cm; the initial side length b of the cathode tool (with square upper and lower surfaces) is 45cm; the anode workpiece is made of aluminum alloy, and the cathode workpiece is made of aluminum alloy blank; the electrolyte is a 10% sodium chloride solution, the electrolytic processing temperature is 37℃, and the processing gap between the foamed aluminum and the aluminum alloy is 1mm; during the electrolysis process, the current between the anode aluminum blank and the cathode foamed aluminum is 9A, and the processing time is 90s, resulting in a surface-textured aluminum alloy.
[0069] like Figure 14 As shown, the Sa value of the treated anode aluminum alloy plate is 4.696 μm and the Sq value is 6.373 μm.
Claims
1. A method for roughening the surface of a metal plate based on foamed metal, characterized in that, Specifically, the foam metal and the metal plate to be roughened are placed opposite each other in an electrolyte, with the foam metal as the cathode and the metal plate to be roughened as the anode, and connected to the negative and anode terminals of an external power supply, respectively; the side of the metal plate to be roughened is positioned opposite the foam metal; the power supply is started to carry out an electrolytic reaction, and after the reaction, a surface roughened metal plate is obtained.
2. The method for roughening the surface of a metal plate based on foamed metal according to claim 1, characterized in that: The foamed metal is aluminum foam.
3. The method for roughening the surface of a metal plate based on foamed metal according to claim 2, characterized in that: The porosity of the foamed metal is 60-65%, and the pore size is 0.1-5 mm.
4. The method for roughening the surface of a metal plate based on foamed metal according to claim 3, characterized in that: The porosity of the foamed metal is 60%, and the pore size is 1-5 mm.
5. The method for roughening the surface of a metal plate based on foamed metal according to claim 1, characterized in that: The electrolyte is a neutral salt solution.
6. The method for roughening the surface of a metal plate based on foamed metal according to claim 5, characterized in that: Neutral salt solutions include sodium chloride solutions or sodium nitrate solutions.
7. The method for roughening the surface of a metal plate based on foamed metal according to claim 6, characterized in that: The mass concentration of the electrolyte is 1-10%.
8. The method for roughening the surface of a metal plate based on foamed metal according to claim 1, characterized in that: The distance between the foamed metal and the metal plate to be roughened is 0.1 to 1 mm.
9. The method for roughening the surface of a metal plate based on foamed metal according to claim 1, characterized in that: During the electrolysis process, a constant current method is used, with a current of 5 to 9 A.
10. The method for roughening the surface of a metal plate based on foamed metal according to claim 9, characterized in that: The current is 8-9A.