Stainless steel electrolytic polishing treatment liquid as well as preparation method and use method thereof

Abstract

The invention provides a stainless steel electrolytic polishing treatment solution as well as a preparation method and a use method thereof. The stainless steel electrolytic polishing treatment liquid comprises sulfuric acid, phosphoric acid, citric acid and saccharin. The volume fraction of the sulfuric acid is 600 to 700 mL / L, the volume fraction of the phosphoric acid is 200 to 300 mL / L, the volume fraction of the citric acid is 10 to 15 mL / L, and the mass concentration of the saccharin is 0.1 to 0.3 mg / L. The invention provides a unique formula, the formula is not only suitable for renovating the waste stainless steel electrolyte barrel, but also can ensure the high quality of the polishing solution, the stainless steel packaging barrel subjected to electrolytic polishing treatment by adopting the formula does not generate a metamorphic layer and has no additional stress, and meanwhile, the stainless steel packaging barrel has the advantages of corrosion resistance, surface rust prevention, beautiful appearance and the like; the cost is obviously reduced, and the target of long-term recycling is achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of metal surface treatment, and in particular relates to a stainless steel electrolytic polishing treatment liquid and a preparation method and a use method thereof. Background Art

[0002] At present, the recycling industry of used steel drums in my country is developing slowly. The waste packaging drums that are discarded or piled up randomly will cause a series of environmental problems such as air pollution, water pollution and soil pollution. Especially those hazardous waste packaging drums that contain or are directly contaminated with hazardous wastes are particularly serious. Therefore, in the context of increasingly tight global energy, the recycling of used packaging drums is of great significance to resource circulation and environmental protection.

[0003] Stainless steel packaging barrels for electrolytes of new energy batteries cannot be recycled due to rust and dirt after long-term use. Coupled with the high procurement cost, disposal has become a major problem in the industry. The current electrochemical polishing treatment method is limited to brightening the surface of stainless steel workpieces, and there is little research on waste stainless steel packaging barrels for electrolytes. Existing research cannot simultaneously meet the high quality requirements of packaging barrels and products, and it is difficult to achieve the goal of long-term recycling.

[0004] Therefore, how to electrochemically polish the electrolyte packaging barrels with a low-cost process while meeting the high quality requirements of the packaging barrels and products and achieving long-term recycling has become a technical problem that needs to be solved urgently. Summary of the invention

[0005] In view of the deficiencies of the prior art, the purpose of the present invention is to provide a stainless steel electrolytic polishing treatment liquid and a preparation method and a use method thereof. The present invention proposes a unique stainless steel electrolytic polishing treatment liquid formula, which is not only suitable for the renovation of stainless steel electrolyte barrels that are rusted and dirty due to containing battery electrolytes, but also ensures the high quality of the polishing liquid. Its advantages are: high polishing efficiency; the surface brightness of the polished stainless steel electrolyte barrel is better than that of traditional electrolytes; the current density is reduced during electrolytic polishing, which prolongs the service life. Therefore, the stainless steel electrolyte barrel after electrolytic polishing using the formula provided by the present invention will not produce a metamorphic layer and no additional stress. At the same time, it has the advantages of corrosion resistance, surface rust prevention and appearance beautification, which significantly reduces costs and achieves the goal of long-term recycling.

[0006] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0007] In a first aspect, the present invention provides a stainless steel electrolytic polishing treatment solution, wherein the stainless steel electrolytic polishing treatment solution comprises sulfuric acid, phosphoric acid, citric acid and saccharin.

[0008] The volume fraction of the sulfuric acid is 600-700 mL / L, the volume fraction of the phosphoric acid is 200-300 mL / L, the volume fraction of the citric acid is 10-15 mL / L, and the mass concentration of the saccharin is 0.1-0.3 mg / L.

[0009] The present invention proposes a unique stainless steel electrolytic polishing treatment liquid formula, which is not only suitable for the renovation of stainless steel electrolyte barrels that are rusted and dirty due to containing battery electrolyte, but also ensures the high quality of the polishing liquid. Its advantages are: high polishing efficiency; the surface brightness of the polished stainless steel electrolyte barrel is better than that of the traditional electrolyte; the current density is reduced during the electrolytic polishing treatment, which prolongs the service life. Therefore, the stainless steel electrolyte barrel after electrolytic polishing with the formula provided by the present invention will not produce a metamorphic layer, no additional stress, and can remove or reduce the original stress layer. At the same time, it has the advantages of corrosion resistance, surface rust prevention and appearance beautification. Even the concave places that are difficult to reach by mechanical polishing can be leveled, and the surface rust prevention ability is significantly improved. In addition, the cost is significantly reduced, and the goal of long-term recycling can be achieved.

[0010] In the present invention, sulfuric acid, as the main acidic component in the stainless steel electrolytic polishing treatment liquid, not only provides the required acidic environment to promote the smooth progress of the electrolytic polishing treatment process, but also has a certain corrosiveness, which helps to remove the rust and oxide layer on the surface of the stainless steel electrolyte barrel; phosphoric acid plays an auxiliary role in the stainless steel electrolytic polishing treatment liquid, and together with sulfuric acid, it constructs an acidic environment, and at the same time has corrosiveness, which can effectively remove the oxide layer; citric acid in the stainless steel electrolytic polishing treatment liquid can not only improve the acidity of the polishing treatment liquid, thereby enhancing the polishing effect, but also prevent the formation of an oxide layer on the surface of the stainless steel electrolyte barrel, further improving the polishing quality, and the addition of citric acid can play a lubricating role. The lubrication and cooling effects help to improve the conductivity of the surface of the stainless steel electrolyte barrel and promote the smooth progress of the electrolytic polishing process. In addition, it can also play the role of a surfactant, which helps to clean the surface of the stainless steel electrolyte barrel and even form a uniform passivation layer to effectively protect the surface of the stainless steel electrolyte barrel from corrosion; saccharin can prevent the formation of an oxide layer on the surface of the stainless steel electrolyte barrel, thereby improving the polishing quality, and can also improve the conductivity of the surface of the stainless steel electrolyte barrel and promote the smooth progress of the electrolytic polishing process. Secondly, it also has a surface active effect and cleans the metal surface. In addition, saccharin can form a uniform passivation film to effectively protect the surface of the stainless steel electrolyte barrel from corrosion.

[0011] In summary, the above components work together to produce a synergistic effect, which can not only achieve the simultaneous polishing of multiple items and improve the polishing efficiency, but also effectively remove or reduce the original stress layer of the stainless steel electrolyte barrel. The barrel size accuracy and shape accuracy after polishing can be precisely controlled within 0.01mm. In addition, the formula has high brightness, and the current density required for electrolysis is significantly reduced, which significantly extends the service life of the electrolyte.

[0012] In the present invention, the volume fraction of the sulfuric acid is 600-700 mL / L, for example, it can be 600 mL / L, 650 mL / L or 700 mL / L, the volume fraction of the phosphoric acid is 200-300 mL / L, for example, it can be 200 mL / L, 250 mL / L or 300 mL / L, the volume fraction of the citric acid is 10-15 mL / L, for example, it can be 10 mL / L, 12 mL / L or 15 mL / L, and the mass concentration of the saccharin is 0.1-0.3 mg / L, for example, it can be 0.1 mg / L, 0.2 mg / L or 0.3 mg / L, etc.

[0013] In the present invention, sulfuric acid is used as an activator and is the main component in the polishing liquid to ensure a normal polishing process. If its content is too low, excessive corrosion will occur on the polishing surface, which is manifested as uniform and dense pitting; if its content is too high, serious uneven corrosion will occur.

[0014] In the present invention, if the phosphoric acid content is too high, the electrolyte resistance will increase, the salinity will increase, and a higher voltage will be required, which will slow down the polishing speed; if the phosphoric acid content is too low, the activation tendency will increase, resulting in uneven corrosion on the stainless steel surface.

[0015] In the present invention, if the content of citric acid is too high, it may cause uneven polishing or reduced surface quality; if the content of citric acid is too low, it may cause uneven polishing or reduced surface quality.

[0016] In the present invention, if the content of saccharin is too high, the electrolyte may be unstable and the electrolysis effect may be affected; if the content of saccharin is too low, corrosion may not be effectively inhibited and the protective performance of the electrolyte may be reduced.

[0017] Preferably, the stainless steel electrolytic polishing treatment liquid also contains an additive.

[0018] Preferably, the auxiliary agent includes a brightener.

[0019] In the present invention, the brightener can form a complex phosphate film to prevent electrolytic nickel from corroding stainless steel in a non-powered state, which helps to promote the cultivation and development of the polished surface and achieves selective dissolution to obtain a smooth and bright surface. In addition, the brightener can also effectively prevent corrosion and oxidation, ensuring the high quality of the surface of the polished stainless steel electrolyte barrel.

[0020] Preferably, the volume fraction of the auxiliary agent is 0.2-0.5 mL / L, for example, it can be 0.2 mL / L, 0.3 mL / L, 0.4 mL / L or 0.5 mL / L.

[0021] In a second aspect, the present invention provides a method for preparing the stainless steel electrolytic polishing treatment solution as described in the first aspect, the preparation method comprising the following steps:

[0022] The stainless steel electrolytic polishing treatment liquid is prepared by mixing sulfuric acid, phosphoric acid, citric acid and saccharin.

[0023] Preferably, the mixing process is accompanied by stirring.

[0024] In a third aspect, the present invention provides a method for using the stainless steel electrolytic polishing treatment solution as described in the first aspect, the method comprising the following steps:

[0025] The waste stainless steel electrolyte barrel is pretreated, and then the pretreated stainless steel electrolyte barrel is electrolytically polished with a stainless steel electrolytic polishing treatment liquid, and then post-processed to obtain a qualified workpiece.

[0026] It should be pointed out that the electrolytic polishing treatment is to immerse the stainless steel electrolyte barrel into the stainless steel electrolytic polishing treatment solution, which serves as the anode material. The electrochemical dissolution phenomenon produced by the anode in the electrolytic cell is used to cause the microscopic bumps on the surface of the stainless steel electrolyte barrel to undergo anodic dissolution, thereby making the surface smooth and producing a metallic luster. This process is also called electrochemical polishing.

[0027] It should be noted that in the electrolytic polishing process of the present invention, the waste stainless steel electrolyte barrel is used as the anode and connected to the positive electrode of the DC power supply; at the same time, a conductive material is used as the cathode material connected to the negative electrode of the DC power supply; the stainless steel electrolytic polishing treatment liquid is used as the electrolyte, and the DC power supply is turned on to perform the electrochemical polishing process.

[0028] It is worth noting that during the electrochemical polishing process, the waste stainless steel electrolyte barrel and the cathode material are kept at a certain distance and immersed in the electrolyte, and are energized for a period of time under specific conditions. During the energization period, a viscous mucous film with high resistivity will form on the surface of the stainless steel electrolyte barrel, and its thickness is unevenly distributed on the surface of the workpiece. Due to the uneven distribution of the viscous mucous film and current density, the microscopic protrusions on the surface of the packaging barrel will dissolve first, while the size of the microscopic concave parts will decrease more slowly, which leads to a decrease in the surface roughness of the packaging barrel and gradually transforms it into a smooth and shiny surface.

[0029] It should be pointed out that the factors that affect the quality of electrochemical polishing include: 1) electrolyte: the formula and proportion of the electrolyte should be determined according to the properties of the processed parts and the selected cathode material; 2) current density: electrochemical polishing is usually carried out at a higher current density. However, too high a current density will cause too much oxygen to precipitate from the anode, making the electrolyte close to boiling, thus affecting the polishing quality; 3) electrolyte temperature: lower temperatures will slow down the dissolution rate, thereby reducing production efficiency. In addition, the electrolyte should be stirred to promote flow, remove electrolysis products in time, and reduce temperature gradients; 4) polishing time: the polishing time should not be too long, because different parts have their specific optimal polishing time; 5) the metallographic structure of the workpiece: the more uniform and dense the metallographic structure of the workpiece, the better the polishing effect; 6) the original roughness of the polished surface of the workpiece: generally speaking, if the substrate roughness of the workpiece surface is lower than Ra1.6, electrochemical polishing will be the best.

[0030] Preferably, the pretreatment step includes pre-cleaning, manual polishing, water washing, degreasing and rust removal, and pickling performed in sequence.

[0031] Preferably, the temperatures of the washing solutions for pre-washing, water washing and acid washing are independently 15-25°C, such as 15°C, 20°C or 25°C, etc., and the washing time is independently 15-20s, such as 15s, 18s or 20s, etc.

[0032] Preferably, in the process of degreasing and derusting, the reagent used is an organic solvent. It should be noted that the organic solvent can dissolve grease and promote its volatilization.

[0033] Preferably, during the degreasing and rust removal process, the operating temperature is 50-60°C, such as 50°C, 55°C or 60°C, and the operating time is 20-30min, such as 20min, 25min or 30min.

[0034] Preferably, during the electrolytic polishing process, the pretreated stainless steel electrolyte barrel is hung in the stainless steel electrolytic polishing treatment solution, and the hanging tooling is made of titanium mesh.

[0035] The present invention adopts a tooling made of titanium mesh, which has excellent corrosion resistance and a long service life, and titanium ions will not have adverse effects on the stainless steel electrolytic polishing treatment liquid.

[0036] It should be noted that in the electrolytic polishing process, the required equipment includes: 1) DC power supply: two-phase 220V or three-phase 380V power supply can be selected; 2) Rectifier: electrolytic polishing does not have strict requirements on the power supply waveform, and a thyristor rectifier or a high-frequency rectifier can be used; the no-load voltage range of the rectifier is 0-20V, and the load voltage (working voltage) is 8-10V. If the working voltage is lower than 6V, the polishing speed will slow down and the brightness will be insufficient; the current of the rectifier should be determined according to the size of the customer's workpiece; 3) Electrolytic cell and supporting facilities (anode rod): The electrolytic cell can be made of polyvinyl chloride hard plate welding. Three electrode rods should be installed on the cell. The middle one is a movable anode rod, which is connected to the anode (or positive pole) of the power supply, and the two sides are cathode rods, which are connected to the cathode (negative pole) of the power supply; 4) Heating and cooling system: In terms of heating, quartz heating tubes or titanium heating tubes can be used as heat sources; as for the cooling system, the coil design is suitable for both heating and cooling processes.

[0037] Preferably, the specific parameters of the electrolytic polishing process include:

[0038] The cathode material includes titanium mesh and copper, the voltage is 6-15V (for example, it can be 6V, 10V or 15V, etc.), and the current density is 18-24A / dm 2 (For example, it can be 18A / dm 2 、20A / dm 2 or 24A / dm 2 The electrolytic polishing treatment time is 15-30 min (for example, it can be 15 min, 20 min or 30 min, etc.), and the working temperature of the stainless steel electrolytic polishing treatment solution is 50-75°C (for example, it can be 50°C, 60°C or 75°C, etc.).

[0039] In the present invention, if the current density is too high, too much oxygen will be released from the anode, causing the electrolyte to nearly boil, thus affecting the polishing quality.

[0040] Preferably, the post-treatment step includes a neutralization treatment, a sealing treatment and a drying treatment performed sequentially.

[0041] Preferably, the specific method of the neutralization treatment includes:

[0042] Place the stainless steel electrolyte barrel after electrolytic polishing in a cleaning tank, adjust the pH value, soak for 3-5 minutes (for example, 3 minutes, 4 minutes or 5 minutes, etc.), and then wash with water.

[0043] Preferably, during the sealing process, hot water is used to clean the stainless steel electrolyte barrel after the neutralization treatment.

[0044] Preferably, the temperature of the hot water is 70-80°C, such as 70°C, 75°C or 80°C, etc., and the cleaning time of the hot water is 3-5 minutes, such as 3 minutes, 4 minutes or 5 minutes, etc.

[0045] Preferably, the drying temperature is 50-60°C, such as 50°C, 55°C or 60°C, and the drying time is 15-30min, such as 15min, 20min or 30min.

[0046] Preferably, the method of use comprises the following steps:

[0047] (1) Pretreatment:

[0048] Pre-clean the used stainless steel electrolyte barrels to remove the logos, offset printing on the barrels and impurities, dust and particles in the gaps of the skirts.

[0049] The pre-cleaned stainless steel electrolyte barrel is manually polished (for example, the surface and inner cavity of the stainless steel electrolyte barrel are polished and grinded by a manual polishing machine and an electric inner hole grinder) to repair the surface scratches, roughening and excessive corrosion of the surface layer.

[0050] Wash the manually polished stainless steel electrolyte barrel with water (using a high-pressure water gun) to remove the dust and particles remaining after polishing.

[0051] The washed stainless steel electrolyte barrel is degreased and derusted, and then placed in a pickling tank for pickling and derusting.

[0052] (2) Electrolytic polishing treatment:

[0053] The stainless steel electrolytic polishing treatment liquid is used to electrolytically polish the pretreated stainless steel electrolyte barrel, wherein the cathode material includes titanium mesh and copper, the voltage is 6-15V, and the current density is 18-24A / dm 2 .

[0054] (3) Post-processing:

[0055] Place the stainless steel electrolyte barrel after electrolytic polishing in a cleaning tank for neutralization, adjust the pH value, soak for 3-5 minutes, and then rinse with water.

[0056] The stainless steel electrolyte barrel is sealed with hot water, the temperature of the hot water is 70-80°C, and the cleaning time of the hot water is 3-5 minutes.

[0057] The sealed stainless steel electrolyte barrel is dried at a temperature of 50-60°C for 15-30 minutes.

[0058] The numerical range described in the present invention not only includes the point values ​​listed above, but also includes any point values ​​between the above numerical ranges that are not listed. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0059] Compared with the prior art, the present invention has the following beneficial effects:

[0060] (1) The present invention proposes a unique stainless steel electrolytic polishing treatment liquid formula, which is not only suitable for the renovation of stainless steel packaging barrels that are rusted and dirty due to containing battery electrolyte, but also ensures the high quality of the polishing liquid. Its advantages are: high polishing efficiency; the surface brightness of the packaging barrel after polishing is better than that of traditional electrolyte; the current density is reduced during electrolytic polishing, which prolongs the service life. Therefore, the stainless steel packaging barrel after electrolytic polishing using the formula provided by the present invention will not produce a degenerate layer and has no additional stress. At the same time, it has the advantages of corrosion resistance, surface rust prevention and appearance beautification, which significantly reduces costs and achieves the goal of long-term recycling.

[0061] (2) The stainless steel electrolytic polishing treatment liquid proposed in the present invention can be used to process hard and soft materials that are difficult to process by mechanical polishing, as well as thin-walled, complex-shaped or small parts and products.

[0062] (3) The stainless steel electrolytic polishing treatment solution proposed in the present invention supports batch polishing at the same time, which significantly improves production efficiency.

[0063] (4) The surface roughness of the stainless steel electrolyte barrel after polishing with the stainless steel electrolytic polishing solution provided by the present invention is at least two orders of magnitude lower than the original surface roughness, and the dimensional accuracy and shape accuracy can be controlled within 0.01 mm. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] Figure 1 This is a schematic diagram of the outer surface of the waste stainless steel electrolyte barrel in Example 1 of the present invention.

[0065] Figure 2 Schematic diagram of the inner surface of the waste stainless steel electrolyte barrel in Example 1 of the present invention.

[0066] Figure 3 This is a schematic diagram of the flange and skirt portion of the waste stainless steel electrolyte barrel in Example 1 of the present invention.

[0067] Figure 4 Schematic diagram of the outer surface of the stainless steel electrolyte barrel after electrolytic polishing in Example 1 of the present invention.

[0068] Figure 5 Schematic diagram of the inner surface of the stainless steel electrolyte barrel after electrolytic polishing in Example 1 of the present invention.

[0069] Figure 6 Schematic diagram of the flange and skirt portion of the stainless steel electrolyte barrel after electrolytic polishing in Example 1 of the present invention. DETAILED DESCRIPTION

[0070] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0071] It should be noted that the used stainless steel electrolyte barrels used below are all rusted and dirty stainless steel packaging barrels for electrolyte.

[0072] Example 1

[0073] This embodiment provides a stainless steel electrolytic polishing treatment solution, which includes sulfuric acid, phosphoric acid, citric acid, saccharin, an additive and a solvent.

[0074] The volume fraction of the sulfuric acid is 650 mL / L, the volume fraction of the phosphoric acid is 250 mL / L, the volume fraction of the citric acid is 12 mL / L, the mass concentration of the saccharin is 0.2 mg / L, the auxiliary agent is a brightener, the brightener includes chromic anhydride, and the volume fraction of the auxiliary agent is 0.3 mL / L; the solvent is water.

[0075] The stainless steel electrolytic polishing treatment liquid is in the form of a bright white liquid.

[0076] This embodiment also provides a method for preparing the above-mentioned stainless steel electrolytic polishing treatment liquid, and the preparation method comprises the following steps:

[0077] The stainless steel electrolytic polishing treatment liquid is prepared by mixing and stirring sulfuric acid, phosphoric acid, citric acid, saccharin, a brightener and water.

[0078] This embodiment also provides a method for using the above-mentioned stainless steel electrolytic polishing treatment liquid, and the method comprises the following steps:

[0079] (1) Pretreatment:

[0080] The used stainless steel electrolyte barrels were pre-cleaned at 20°C for 20 seconds to remove the marks and offset printing on the barrels as well as impurities, dust and particles in the gaps of the skirts.

[0081] The pre-cleaned stainless steel electrolyte barrel is polished and polished on the surface and inner cavity by a manual polishing machine and the surface scratches, roughening and excessive corrosion are repaired.

[0082] The manually polished stainless steel electrolyte barrel is washed with water (a high-pressure water gun may be used) at 20°C for 20 seconds to wash away the dust and particles remaining after polishing.

[0083] The washed stainless steel electrolyte barrel is degreased and derusted at a temperature of 55°C for 25 minutes; then it is placed in a pickling tank for pickling and derusting at a temperature of 20°C for 20 seconds.

[0084] (2) Electrolytic polishing treatment:

[0085] The pretreated stainless steel electrolyte barrel is hung on the electrolytic cell (welded from polyvinyl chloride hard plate, equipped with three electrode rods, the middle one is a movable anode rod (copper tube, the length is the length of the electrolytic cell plus 20cm), which is used to connect the positive pole of the DC power supply, and the electrode rods on both sides are cathode rods (lead plate, the length is the height of the electrolytic cell plus 10cm, the width depends on the length of the electrolytic cell), which are used to connect the negative pole of the power supply, fixed by a clamp, and the clamp material is titanium). The pretreated stainless steel electrolyte barrel is used as the anode, and the positive pole of the DC power supply is connected to the anode of the rectifier (no-load voltage is 15V, load voltage is 9V), titanium alloy and copper are used as cathode materials, and the negative pole of the DC power supply is connected to the cathode of the rectifier, and the stainless steel electrolytic polishing treatment liquid is used as the electrolyte, and the stirring state is maintained, and then the DC power supply (two-phase 220V is selected) is turned on for 20 minutes of electrolytic polishing treatment, the voltage is 10V, and the current density is 20A / dm 2 The working temperature of the stainless steel electrolytic polishing treatment liquid is 60℃.

[0086] (3) Post-processing:

[0087] The stainless steel electrolyte barrel after electrolytic polishing is placed in a cleaning tank for neutralization treatment, the pH value is adjusted, soaked for 4 minutes, and then washed with water.

[0088] The stainless steel electrolyte barrel is sealed with hot water at a temperature of 75°C and the cleaning time of the hot water is 4 minutes.

[0089] The sealed stainless steel electrolyte barrel is dried at a temperature of 55°C for 20 minutes.

[0090] Figure 1 and Figure 4 The schematic diagrams of the outer surfaces of the waste stainless steel electrolyte barrels provided in this embodiment before and after the electrolytic polishing treatment are compared. Figure 2 and Figure 5 The schematic diagrams of the inner surfaces of the waste stainless steel electrolyte barrels provided in this embodiment before and after the electrolytic polishing treatment are compared. Figure 3 and Figure 6The schematic diagrams of the flange and skirt of the waste stainless steel electrolyte barrel provided in this embodiment before and after the electrolytic polishing treatment are compared. Through the comparison, it can be seen that after the electrolyte packaging barrel is subjected to the above-mentioned electrochemical polishing treatment, the barrel body is clean and beautiful, the inside is as bright as new, and the flange and skirt are clean and tidy, and as bright as before.

[0091] Example 2

[0092] This embodiment provides a stainless steel electrolytic polishing treatment solution, which includes sulfuric acid, phosphoric acid, citric acid, saccharin, an additive and a solvent.

[0093] The volume fraction of the sulfuric acid is 600 mL / L, the volume fraction of the phosphoric acid is 200 mL / L, the volume fraction of the citric acid is 15 mL / L, the mass concentration of the saccharin is 0.3 mg / L, the auxiliary agent is a brightener, the brightener includes chromic anhydride, and the volume fraction of the auxiliary agent is 0.2 mL / L; the solvent is water.

[0094] The stainless steel electrolytic polishing treatment liquid is in the form of a bright white liquid.

[0095] This embodiment also provides a method for preparing the above-mentioned stainless steel electrolytic polishing treatment liquid, and the preparation method comprises the following steps:

[0096] The stainless steel electrolytic polishing treatment liquid is prepared by mixing and stirring sulfuric acid, phosphoric acid, citric acid, saccharin, a brightener and water.

[0097] This embodiment also provides a method for using the above-mentioned stainless steel electrolytic polishing treatment liquid, and the method comprises the following steps:

[0098] (1) Pretreatment:

[0099] Pre-clean the used stainless steel electrolyte barrels at 15°C for 20 seconds to remove the logos, offset printing on the barrels and impurities, dust and particles in the gaps of the skirts.

[0100] The pre-cleaned stainless steel electrolyte barrel is polished and polished on the surface and inner cavity by a manual polishing machine and the surface scratches, roughening and excessive corrosion are repaired.

[0101] Wash the manually polished stainless steel electrolyte barrel with water (using a high-pressure water gun) at 15°C for 20 seconds to wash away the dust and particles remaining after polishing.

[0102] The washed stainless steel electrolyte barrel is degreased and derusted at a temperature of 50°C for 30 minutes; then it is placed in a pickling tank for pickling and derusting at a temperature of 15°C for 20 seconds.

[0103] (2) Electrolytic polishing treatment:

[0104] The pretreated stainless steel electrolyte barrel is hung on the electrolytic cell (welded from polyvinyl chloride hard plate, equipped with three electrode rods, the middle one is a movable anode rod (copper tube, length is the length of the electrolytic cell plus 20cm), used to connect the positive pole of the DC power supply, and the electrode rods on both sides are cathode rods (lead plate, length is the height of the electrolytic cell plus 10cm, width depends on the length of the electrolytic cell), used to connect the negative pole of the power supply, fixed by a clamp, the clamp material is titanium), the pretreated stainless steel electrolyte barrel is used as the anode, and the positive pole of the DC power supply is connected to the anode of the rectifier (no-load voltage is 15V, load voltage is 9V), the titanium mesh and copper are used as cathode materials, and the negative pole of the DC power supply is connected to the cathode of the rectifier, the stainless steel electrolytic polishing treatment liquid is used as the electrolyte, and the stirring state is maintained, and then the DC power supply (two-phase 220V is selected) is turned on for 15 minutes of electrolytic polishing treatment, the voltage is 15V, and the current density is 24A / dm 2 The working temperature of the stainless steel electrolytic polishing treatment liquid is 50℃.

[0105] (3) Post-processing:

[0106] The stainless steel electrolyte barrel after electrolytic polishing is placed in a cleaning tank for neutralization treatment, the pH value is adjusted, soaked for 3 minutes, and then washed with water.

[0107] The stainless steel electrolyte barrel is sealed with hot water at a temperature of 70°C and the cleaning time of the hot water is 3 minutes.

[0108] The sealed stainless steel electrolyte barrel is dried at a temperature of 50°C for 30 minutes.

[0109] Example 3

[0110] This embodiment provides a stainless steel electrolytic polishing treatment solution, which includes sulfuric acid, phosphoric acid, citric acid, saccharin, an additive and a solvent.

[0111] The volume fraction of the sulfuric acid is 700 mL / L, the volume fraction of the phosphoric acid is 300 mL / L, the volume fraction of the citric acid is 10 mL / L, the mass concentration of the saccharin is 0.1 mg / L, the auxiliary agent is a brightener, the brightener includes chromic anhydride, and the volume fraction of the auxiliary agent is 0.5 mL / L; the solvent is water.

[0112] The stainless steel electrolytic polishing treatment liquid is in the form of a bright white liquid.

[0113] This embodiment also provides a method for preparing the above-mentioned stainless steel electrolytic polishing treatment liquid, and the preparation method comprises the following steps:

[0114] The stainless steel electrolytic polishing treatment liquid is prepared by mixing and stirring sulfuric acid, phosphoric acid, citric acid, saccharin, a brightener and water.

[0115] This embodiment also provides a method for using the above-mentioned stainless steel electrolytic polishing treatment liquid, and the method comprises the following steps:

[0116] (1) Pretreatment:

[0117] Pre-clean the used stainless steel electrolyte barrels at 25°C for 15 seconds to remove the logos, offset printing on the barrels and impurities, dust and particles in the gaps of the skirts.

[0118] The pre-cleaned stainless steel electrolyte barrel is manually polished (for example, the surface and inner cavity of the stainless steel electrolyte barrel are polished and grinded by a manual polishing machine and an electric inner hole grinder) to repair the surface scratches, roughening and excessive corrosion of the surface layer.

[0119] The manually polished stainless steel electrolyte barrel is washed with water (a high-pressure water gun may be used) at 25°C for 15 seconds to wash away the dust and particles remaining after polishing.

[0120] The washed stainless steel electrolyte barrel is degreased and derusted at a temperature of 50°C for 20 minutes; then it is placed in a pickling tank for pickling and derusting at a temperature of 25°C for 15 seconds.

[0121] (2) Electrolytic polishing treatment:

[0122] The pretreated stainless steel electrolyte barrel is hung on the electrolytic cell (welded from polyvinyl chloride hard plate, equipped with three electrode rods, the middle one is a movable anode rod (copper tube, length is the length of the electrolytic cell plus 20cm), used to connect the positive pole of the DC power supply, and the electrode rods on both sides are cathode rods (lead plate, length is the height of the electrolytic cell plus 10cm, width depends on the length of the electrolytic cell), used to connect the negative pole of the power supply, fixed by a clamp, the clamp material is titanium), the pretreated stainless steel electrolyte barrel is used as the anode, and the positive pole of the DC power supply is connected to the anode of the rectifier (no-load voltage is 15V, load voltage is 9V), titanium alloy and copper are used as cathode materials, and the negative pole of the DC power supply is connected to the cathode of the rectifier, the stainless steel electrolytic polishing treatment liquid is used as the electrolyte, and the stirring state is maintained, and then the DC power supply (two-phase 220V is selected) is turned on for 30 minutes of electrolytic polishing treatment, the voltage is 6V, and the current density is 18A / dm 2 The working temperature of stainless steel electrolytic polishing treatment liquid is 75℃.

[0123] (3) Post-processing:

[0124] The stainless steel electrolyte barrel after electrolytic polishing is placed in a cleaning tank for neutralization treatment, the pH value is adjusted, soaked for 5 minutes, and then washed with water.

[0125] The stainless steel electrolyte barrel is sealed with hot water at a temperature of 70°C and the cleaning time of the hot water is 5 minutes.

[0126] The sealed stainless steel electrolyte barrel is dried at a temperature of 60°C for 15 minutes.

[0127] Example 4

[0128] The difference between this embodiment and embodiment 1 is that the current density of the electrolytic polishing treatment is 25A / cm 2 .

[0129] The rest of the preparation methods and parameters were the same as those in Example 1.

[0130] Example 5

[0131] The difference between this embodiment and embodiment 1 is that during the electrolytic polishing process, the working temperature of the stainless steel electrolytic polishing solution is 40°C.

[0132] The rest of the preparation methods and parameters were the same as those in Example 1.

[0133] Example 6

[0134] The difference between this embodiment and embodiment 1 is that during the electrolytic polishing process, the working temperature of the stainless steel electrolytic polishing treatment liquid is 80°C.

[0135] The rest of the preparation methods and parameters were the same as those in Example 1.

[0136] Example 7

[0137] The difference between this embodiment and embodiment 1 is that the electrolytic polishing treatment time is 10 minutes.

[0138] The rest of the preparation methods and parameters were the same as those in Example 1.

[0139] Example 8

[0140] The difference between this embodiment and embodiment 1 is that the electrolytic polishing treatment time is 35 minutes.

[0141] The rest of the preparation methods and parameters were the same as those in Example 1.

[0142] Comparative Example 1

[0143] The difference between this comparative example and Example 1 is that the stainless steel electrolytic polishing treatment liquid does not contain saccharin.

[0144] The rest of the preparation methods and parameters were the same as those in Example 1.

[0145] Comparative Example 2

[0146] The difference between this comparative example and Example 1 is that the stainless steel electrolytic polishing treatment liquid does not contain citric acid.

[0147] The rest of the preparation methods and parameters were the same as those in Example 1.

[0148] Comparative Example 3

[0149] The difference between this comparative example and Example 1 is that the volume fraction of sulfuric acid in the stainless steel electrolytic polishing treatment solution is 500 mL / L.

[0150] The rest of the preparation methods and parameters were the same as those in Example 1.

[0151] Comparative Example 4

[0152] The difference between this comparative example and Example 1 is that the volume fraction of sulfuric acid in the stainless steel electrolytic polishing treatment solution is 800 mL / L.

[0153] The rest of the preparation methods and parameters were the same as those in Example 1.

[0154] Comparative Example 5

[0155] The difference between this comparative example and Example 1 is that the volume fraction of phosphoric acid in the stainless steel electrolytic polishing treatment solution is 100 mL / L.

[0156] The rest of the preparation methods and parameters were the same as those in Example 1.

[0157] Comparative Example 6

[0158] The difference between this comparative example and Example 1 is that the volume fraction of phosphoric acid in the stainless steel electrolytic polishing treatment solution is 400 mL / L.

[0159] The rest of the preparation methods and parameters were the same as those in Example 1.

[0160] Combination Figures 1 to 6 It can be seen that the surface roughness of the stainless steel electrolyte barrel after polishing based on the stainless steel electrolytic polishing treatment liquid formula provided by the present invention is at least two orders of magnitude lower than the original surface roughness, and the dimensional accuracy and shape accuracy can be controlled within 0.01 mm.

[0161] It can be seen from Examples 1 and 4 that if the current density of the electrolytic polishing treatment is too large, too much oxygen will be released from the anode, causing the electrolyte to nearly boil, thus affecting the polishing quality.

[0162] It can be seen from Examples 1 and 5-6 that during the electrolytic polishing process, it is most ideal to maintain the electrolyte temperature between 50 and 75° C. A low temperature will slow down the polishing rate and reduce the surface brightness; a high temperature will accelerate the corrosion of the electrolyte on the workpiece, resulting in excessive corrosion and may cause the decomposition of the active ingredients of the electrolyte.

[0163] It can be seen from Example 1 and Examples 7-8 that if the electrolytic polishing treatment time is too short, the surface of the stainless steel electrolyte barrel will be insufficiently polished and rough, the metal removal amount may be insufficient, affecting the processing quality, and the electrolyte may not be fully utilized, resulting in waste. If the electrolytic polishing treatment time is too long, it may lead to over-polishing, reduced surface roughness, and even pits; the metal may be excessively dissolved, affecting dimensional accuracy; excessive electrolyte consumption increases costs.

[0164] It can be seen from Example 1 and Comparative Examples 1-2 that if saccharin is not included, the electrolyte has poor stability and is prone to precipitation, resulting in unstable polishing effect and affecting the surface quality of the workpiece; if citric acid is not included, the electrolyte has poor stability and the surface quality of the workpiece is unstable.

[0165] It can be seen from Example 1 and Comparative Examples 3-4 that if the sulfuric acid content in the stainless steel electrolytic polishing treatment solution is too low, it will cause uneven corrosion of the electrolytic surface; conversely, if the sulfuric acid content is too high, the polishing speed will be too fast, which will accelerate the corrosion of the stainless steel electrolyte barrel.

[0166] It can be seen from Example 1 and Comparative Examples 5-6 that if the phosphoric acid content in the stainless steel electrolytic polishing treatment solution is too low, the polishing speed will be accelerated, which is not conducive to the leveling and polishing effects; if the phosphoric acid content is too high, the brightness will decrease and the polishing speed will slow down.

[0167] The applicant declares that the present invention illustrates the process method of the present invention through the above-mentioned embodiments, but the present invention is not limited to the above-mentioned process steps, that is, it does not mean that the present invention must rely on the above-mentioned process steps to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of the raw materials selected by the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A stainless steel electrolytic polishing treatment liquid, characterized in that: The stainless steel electrolytic polishing treatment liquid comprises sulfuric acid, phosphoric acid, citric acid and saccharin; The volume fraction of the sulfuric acid is 600-700 mL / L, the volume fraction of the phosphoric acid is 200-300 mL / L, the volume fraction of the citric acid is 10-15 mL / L, and the mass concentration of the saccharin is 0.1-0.3 mg / L.

2. The stainless steel electrolytic polishing treatment liquid according to claim 1, characterized in that: The stainless steel electrolytic polishing treatment liquid also contains an additive; Preferably, the auxiliary agent includes a brightener; Preferably, the volume fraction of the auxiliary agent is 0.2-0.5 mL / L.

3. A method for preparing a stainless steel electrolytic polishing treatment solution as claimed in claim 1, characterized in that: The preparation method comprises the following steps: The stainless steel electrolytic polishing treatment liquid is prepared by mixing sulfuric acid, phosphoric acid, citric acid and saccharin.

4. A method for using the stainless steel electrolytic polishing treatment solution according to claim 1 or 2, characterized in that: The method of use comprises the following steps: The waste stainless steel electrolyte barrel is pretreated, and then the stainless steel electrolytic polishing treatment liquid is used to perform electrolytic polishing treatment on the pretreated stainless steel electrolyte barrel, and then post-processing is performed to obtain a qualified workpiece.

5. The method of use according to claim 4, characterized in that: The pretreatment steps include pre-cleaning, manual polishing, water washing, degreasing and rust removal, and pickling in sequence; Preferably, the temperatures of the washing solutions for the pre-washing, water washing and acid washing are independently 15-25°C, and the washing time is independently 15-20s; Preferably, during the degreasing and rust removal process, the operating temperature is 50-60° C. and the operating time is 20-30 min.

6. The method of use according to claim 4 or 5, characterized in that: During the electrolytic polishing process, the pretreated stainless steel electrolyte barrel is hung in the stainless steel electrolytic polishing treatment solution, and the hanging tooling is made of titanium mesh.

7. The method of use according to any one of claims 4 to 6, characterized in that: The specific parameters of the electrolytic polishing process include: The cathode materials include titanium mesh and copper, the voltage is 6-15V, and the current density is 18-24A / dm 2 The electrolytic polishing treatment time is 15-30min, and the working temperature of the stainless steel electrolytic polishing treatment solution is 50-75℃.

8. The method of use according to any one of claims 4 to 7, characterized in that: The post-treatment steps include neutralization treatment, sealing treatment and drying treatment performed in sequence; Preferably, the specific method of the neutralization treatment includes: Place the stainless steel electrolyte barrel after electrolytic polishing in the cleaning tank, adjust the pH value, soak for 3-5 minutes, and then wash with water; Preferably, during the sealing process, hot water is used to clean the stainless steel electrolyte barrel after the neutralization treatment; Preferably, the temperature of the hot water is 70-80°C, and the cleaning time of the hot water is 3-5 minutes; Preferably, the temperature of the drying treatment is 50-60° C., and the drying time is 15-30 min.

9. The method of use according to any one of claims 4 to 8, characterized in that: The method of use comprises the following steps: (1) Pretreatment: Pre-clean the used stainless steel electrolyte barrels to remove the logos, offset printing on the barrels and impurities, dust and particles in the gaps of the skirts; Manually polish the pre-cleaned stainless steel electrolyte barrels to repair surface scratches, roughening and excessive corrosion; Wash the hand-polished stainless steel electrolyte barrel with water to rinse away the dust and particles left after polishing; The washed stainless steel electrolyte barrel is degreased and derusted, and then placed in a pickling tank for pickling and derusting; (2) Electrolytic polishing treatment: The stainless steel electrolytic polishing treatment liquid is used to electrolytically polish the pretreated stainless steel electrolyte barrel, wherein the cathode material includes titanium mesh and copper, the voltage is 6-15V, and the current density is 18-24A / dm 2 ; (3) Post-processing: Place the stainless steel electrolyte barrel after electrolytic polishing in a cleaning tank for neutralization, adjust the pH value, soak for 3-5 minutes, and then wash with water; Use hot water to seal the stainless steel electrolyte barrel. The temperature of the hot water is 70-80℃ and the cleaning time of the hot water is 3-5min. The sealed stainless steel electrolyte barrel is dried at a temperature of 50-60°C for 15-30 minutes.

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