An efficient and environmentally friendly low-temperature cleaning system and method for stainless steel oxide layers

Abstract

The present invention relates to an efficient and environmentally friendly low-temperature cleaning system and method for stainless steel oxide layers. The system includes: an electrochemical vibration cleaning device for performing electrochemical vibration cleaning on stainless steel materials; a spray cleaning device for performing spray cleaning on the stainless steel materials after electrochemical vibration cleaning; a blowing and drying device for drying the stainless steel materials after spray cleaning; and a support and transmission device for supporting and transmitting the stainless steel materials. The electrochemical vibration cleaning device, the spray cleaning device, and the blowing and drying device are arranged in sequence along the transmission direction of the support and transmission device. Compared with the prior art, the present invention has the characteristics of high efficiency, good controllability, batch production ability, safety and environmental friendliness in cleaning and removing the oxide layers generated during the raw material production and preparation of stainless steel, high-temperature processing of products, and high-temperature application conditions of products.

Description

Technical Field

[0001] The present invention relates to the technical field of surface treatment of metal materials, and particularly relates to an efficient and environment-friendly low-temperature cleaning system and method for stainless steel oxide layers. Background Art

[0002] Stainless steel materials have good corrosion resistance, high electrical conductivity, good mechanical strength and forming and processing properties, and thus are widely used in various industrial fields. In proton exchange membrane fuel cells, which are considered to be one of the future ultimate energy conversion devices, bipolar plates need to have excellent corrosion resistance, electrical conductivity and mechanical strength. At the same time, in order to achieve high-performance fuel cell design and promote the commercial application of fuel cells, bipolar plate materials also need to have good forming and processing properties. Since stainless steel materials have good corrosion resistance and electrical conductivity, high mechanical strength and good processing and forming properties, they are considered to be one of the main materials for preparing bipolar plates of proton exchange membrane fuel cells. To further improve the forming properties of stainless steel bipolar plates, some researchers have recently proposed a method for preparing stainless steel bipolar plates by high-temperature thermoforming process. Although the high-temperature thermoforming process can better improve the forming properties of stainless steel bipolar plates and realize the structural design of high-performance fuel cells, a difficult-to-remove oxide layer will be formed on the stainless steel bipolar plates during the high-temperature forming process, and the electrical conductivity of the bipolar plates will be significantly reduced. Therefore, it is necessary to remove the oxide layer on the surface of the stainless steel bipolar plates. In addition, an oxide layer will be formed on the surface of stainless steel during the processes such as rolling production of stainless steel sheets, hot forming and processing of stainless steel products at high temperature, and use of stainless steel products in high-temperature environments. In most cases, the oxide layer on the surface of stainless steel needs to be removed to meet the requirements of further processing and preparation or use.

[0003] The chemical composition of the oxide layer on the stainless steel surface is mainly composed of two or more combinations of substances such as Fe2O3, Fe3O4, FeO, Cr2O3, NiO, Cr2O3·FeO, and Ni·Fe2O3. Moreover, the chemical composition and composition structure of the oxide layer on the stainless steel surface change with the heating temperature and heating time. At lower temperatures, the oxide layer on the stainless steel surface is mainly composed of Fe2O3, Fe3O4, and Cr2O3, and this oxide layer is generally thin and dense. As the forming or heating temperature increases, spinel structures such as FeO or Cr2O3·FeO, Ni·Fe2O3 may form inside the stainless steel oxide layer. At the same time, with the increase in temperature and heating time, the thickness of the oxide layer will continuously increase. Therefore, it is more difficult to remove the oxide film formed on stainless steel under high-temperature or long-time heating conditions. For the removal of the stainless steel oxide layer, pickling (HNO3+HF, H2SO4+HNO3+HCl, etc.) or mechanical treatment (shot peening, polishing, etc.) methods are generally used at present. Chinese patent document CN111155119A proposes a method for cleaning the oxide layer on the surface of a stainless steel sensor. Although this method does not require the use of hydrofluoric acid, it still requires a mixed solution of nitric acid, sulfuric acid, and potassium dichromate, and at the same time, the solution needs to be heated to 80°C to 120°C. Chinese patent document CN109112552A discloses a cleaning agent and cleaning method for the oxide layer on the stainless steel surface. Although this method does not contain hydrofluoric acid, which is highly harmful to the environment and human health, it contains relatively high concentrations of hydrochloric acid, hydrogen peroxide, and hexamethylenetetramine, which have a certain degree of impact on the human body and the environment. Moreover, hexamethylenetetramine is flammable and explosive, and there is a risk of explosion when used simultaneously with hydrogen peroxide. Chinese patent document CN100577880C discloses an acid cleaning solution and acid cleaning method for removing the oxide layer of hot-rolled chromium-containing stainless steel using sulfuric acid as the pickling medium and hydrochloride salts of fatty amines as additives. Although this method does not use nitric acid and hydrofluoric acid, its treatment time is long, the efficiency is low, and the operation needs to be carried out under the condition of 80°C to 90°C. Chinese patent document CN107779882A invented a cleaning solution mainly composed of organic compounds and a method for removing the oxide layer on the surface of a stainless steel workpiece by immersing the stainless steel workpiece in this solution at room temperature. However, its oxide layer cleaning time is long, and the organic substances contained are harmful to the environment and the human body to a certain extent. Chinese patent document CN103820797A invented an oxide layer cleaning solution and cleaning method mainly composed of cyclodextrin, organic acid, and a composite surfactant. The cleaning time of this invention is relatively short, and the cleaning solution is less harmful to the environment. However, the preparation process of the cleaning solution is relatively complex, the preparation time is long, and the cleaning solution needs to be heated to a certain temperature to improve the cleaning efficiency.Chinese patent document CN105586603A discloses a method for removing the oxide layer on the surface of stainless steel by combining an alkaline salt bath and pickling. Although this method can effectively remove the oxide layer on the surface of stainless steel, the salt bath process needs to be carried out at a high temperature, and the oxide layer removal time is relatively long. Chinese patent document CN110508630A discloses a method for physically and mechanically removing the oxide layer on the surface of stainless steel. This method does not require the use of acids and organic solvents, has a good environmental protection effect, and is less harmful to the human body. However, this method cannot process materials with high surface quality requirements or workpieces with relatively complex shapes, nor can it be used for removing the oxide layer on the surface of ultra-thin stainless steel plates. Chinese patent document CN112267122A proposes a cleaning solution and method for the oxide layer on the surface of stainless steel. This method can relatively effectively remove the oxide layer. However, a relatively large amount of ammonium bifluoride needs to be added to the cleaning solution in this method, which is harmful to both the human body and the environment. In addition, Chinese patent documents CN113584493A and CN113584498A respectively propose a cold rolling and hot rolling stainless steel pickling process and equipment. The main principle is to use the annealing temperature to increase the pickling reaction rate, thereby reducing energy consumption. However, the hydrochloric acid used in this method is likely to generate irritating acid mist at a relatively high temperature of the strip steel, which is harmful to both the human body and the environment. At the same time, the method in this patent is mainly used for stainless steel strips, and it is difficult to remove the oxide layer on the surface of stainless steel workpieces with relatively complex shapes. Chinese patent document CN207057087U discloses a device for removing the oxide layer on the surface of stainless steel. However, this device is mainly used for stainless steel plates, and certain plastic deformation may occur to the stainless steel substrate during the oxide layer removal process. Chinese patent document CN208695746U discloses a device for removing the oxide layer on the surface of stainless steel. This device is mainly used for removing the oxide layer on stainless steel tools and cannot achieve batch removal of the oxide layer on the surfaces of stainless steel plates, wires, profiles, etc. Chinese patent document CN213351974U discloses a device for removing the oxide layer on the surface of stainless steel coils. This device uses a physical grinding method to remove the oxide layer, and it is difficult to remove the oxide layer on ultra-thin stainless steel strip materials or plates with high surface quality requirements. Chinese patent document CN111519238A proposes a method and equipment for electrolytically removing the oxide layer on the surface of stainless steel. However, this method needs to heat the solution to 40°C to 70°C, the oxide layer removal time is relatively long, and the energy consumption is relatively high.

[0004] Therefore, overcoming the deficiencies of existing methods and devices and achieving efficient, safe, and environmentally friendly removal of the oxide layer on the surface of stainless steel not only can improve the quality and production efficiency of thermoformed bipolar plates for proton exchange membrane fuel cells, but also has great significance in improving the quality of stainless steel raw materials and products, enhancing the production capacity of stainless steel products, improving the working environment of workers, and protecting the natural environment. Summary of the Invention

[0005] The object of the present invention is to overcome the defects of the above-mentioned existing technologies and provide an efficient and environmentally friendly low-temperature cleaning system and method for stainless steel oxide layers, which can be applied to the cleaning and removal of oxide layers on the surfaces of fuel cell hot-formed stainless steel parts (such as hot-formed stainless steel bipolar plates), and can also be used for the cleaning and removal of oxide layers during the production of stainless steel strips, sheets, profiles, pipes and wires. At the same time, it can also be used for the cleaning and removal of oxide layers generated during the hot processing or high-temperature use of other stainless steel products.

[0006] The object of the present invention can be achieved by the following technical solutions:

[0007] An efficient and environmentally friendly low-temperature cleaning system for stainless steel oxide layers, the system includes:

[0008] An electrochemical vibration cleaning device for electrochemically vibrating and cleaning stainless steel materials;

[0009] A spray cleaning device for spray cleaning the stainless steel materials after electrochemical vibration cleaning;

[0010] A blast drying device for drying the stainless steel materials after spray cleaning;

[0011] A support transmission device for supporting and transmitting stainless steel materials, and the electrochemical vibration cleaning device, the spray cleaning device and the blast drying device are arranged in sequence along the transmission direction of the support transmission device.

[0012] Preferably, the electrochemical vibration cleaning device includes an electrochemical vibration cleaning tank, an electrochemical cleaning solution, an ultrasonic vibrator, a voltage and current control component and an electrochemical cleaning solution replenishment and recovery component. The electrochemical cleaning solution is placed in the electrochemical vibration cleaning tank, the ultrasonic vibrator is arranged on the electrochemical vibration cleaning tank, the voltage and current control component is installed in the electrochemical vibration cleaning tank to control the current density passing through the stainless steel materials, and the electrochemical cleaning solution replenishment and recovery component is connected to the electrochemical vibration cleaning tank.

[0013] Preferably, the electrochemical cleaning solution replenishment and recovery component includes an electrochemical cleaning solution recovery, treatment and replenishment tank, and the electrochemical cleaning solution recovery, treatment and replenishment tank contains a replenishment cleaning solution. The electrochemical cleaning solution recovery, treatment and replenishment tank is connected to the electrochemical vibration cleaning tank through a liquid supply pipeline and a recovery pipeline.

[0014] Preferably, the spray cleaning device includes a spray cleaning tank and cleaning nozzles. The cleaning nozzles are distributed on the top and bottom of the spray cleaning tank and are used to spray the front and back sides of the stainless steel materials.

[0015] Preferably, the air-blowing drying device includes an air-blowing drying box and air-blowing fans, and the air-blowing fans are distributed at the top and bottom of the air-blowing drying box for air-blowing drying of the front and back sides of the stainless steel material.

[0016] Preferably, the electro-chemical cleaning solution includes an H2SO4 solution with a mass fraction of 1% to 40%.

[0017] Preferably, the spray cleaning solution in the spray cleaning device includes a NaHCO3 solution with a mass fraction of 1% to 10% or clear water.

[0018] Preferably, the system further includes a stainless steel material clamping and winding device, and two sets of the stainless steel material clamping and winding devices are provided and distributed at the head and tail ends of the transmission line of the support transmission device.

[0019] An efficient and environmentally friendly low-temperature cleaning method for stainless steel oxide layers, the method comprising:

[0020] S1. Prepare an H2SO4 solution with a mass fraction of 1% to 40% as the electro-chemical vibration cleaning solution;

[0021] S2. Place the stainless steel material to be cleaned in an electro-chemical vibration cleaning tank, add the prepared electro-chemical vibration cleaning solution, and turn on the ultrasonic vibrator;

[0022] S3. Apply a voltage to the stainless steel material and monitor the current density passing through the stainless steel material;

[0023] S4. After the electro-chemical vibration cleaning is completed, spray and clean the stainless steel material with a NaHCO3 solution with a mass fraction of 1% to 10% or clear water to remove the residual sulfuric acid solution on the surface of the stainless steel material;

[0024] S5. Perform air-blowing drying treatment on the spray-cleaned stainless steel material;

[0025] S6. Wind and package the cleaned stainless steel material.

[0026] Preferably, when the mass fraction of H2SO4 in the electro-chemical vibration cleaning solution is less than 1%, or the total mass fraction of Fe 2+ 、Fe 3+ is higher than 2%, the solution in the electro-chemical vibration cleaning tank is recycled, the contents of H2SO4 and Fe 2+ 、Fe 3+ in the solution are adjusted, and the electro-chemical vibration cleaning solution in the electro-chemical vibration cleaning tank is supplemented.

[0027] Compared with the prior art, the present invention has the following advantages:

[0028] (1) The stainless steel oxide layer cleaning system and method in the present invention are easy to operate and use, can be carried out at room temperature, and can efficiently remove oxide layers of different thicknesses on the surface of stainless steel.

[0029] (2) The stainless steel oxide layer cleaning system and method in the present invention can achieve batch removal of the surface oxide layer generated during the high-temperature production and preparation of stainless steel strips, sheets, wires, pipes, and profiles.

[0030] (3) The stainless steel oxide layer cleaning system and method in the present invention have a wide range of applications. They can not only clean and remove the surface oxide layer generated during the high-temperature production and preparation of stainless steel strips, sheets, wires, pipes, and profiles, but also remove the surface oxide layer of hot-formed stainless steel components, such as the surface oxide layer of hot-formed stainless steel bipolar plates. At the same time, they can also clean and remove the surface oxide layer formed when stainless steel components are used in a high-temperature environment.

[0031] (4) The stainless steel oxide layer cleaning system and method in the present invention are safe and environmentally friendly. The container solution only contains a low concentration of sulfuric acid solution, without harmful acidic substances such as hydrofluoric acid and hydrochloric acid to the human body. No toxic or harmful gases are generated during the cleaning process, which is harmless to the health of operating workers and is beneficial to environmental protection. Brief Description of the Drawings

[0032] Figure 1 It is a schematic structural diagram of an efficient and environmentally friendly low-temperature cleaning system for stainless steel oxide layers;

[0033] Figure 2 It is a flow block diagram of an efficient and environmentally friendly low-temperature cleaning method for stainless steel oxide layers;

[0034] Figure 3 Comparison chart of the corrosion performance of SS316L stainless steel after removing oxide layers formed at different temperatures.

[0035] In the figure, 101 and 601 are stainless steel material clamping and winding devices, 201 is a support and transmission device, 301 is an electrochemical vibration cleaning tank, 302 is an electrochemical cleaning solution, 303 and 304 are voltage loading modules, 305 is a current monitoring system, 306 is an ultrasonic vibrator, 307 is an electrochemical cleaning solution recycling, treatment, and replenishment tank, 308 is a replenishing cleaning solution, 401 is a spray cleaning tank, 402 is a spray cleaning solution, 403 is a cleaning nozzle, 501 is a blast drying oven, and 502 is a blast fan. Detailed Embodiments

[0036] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. Note that the following description of the embodiments is only illustrative in nature, and the present invention is not intended to limit the objects to which it applies or its uses, and the present invention is not limited to the following embodiments.

[0037] As Figure 1 , the present invention provides an efficient and environmentally friendly low-temperature cleaning system for stainless steel oxide layers, and the system includes:

[0038] An electrochemically vibrated cleaning device for electrochemically vibrating and cleaning stainless steel materials;

[0039] A spray cleaning device for spray cleaning the stainless steel materials after electrochemically vibrated cleaning;

[0040] A blast drying device for drying the stainless steel materials after spray cleaning;

[0041] A support and transmission device 201 for supporting and transmitting stainless steel materials, and the electrochemically vibrated cleaning device, the spray cleaning device, and the blast drying device are arranged in sequence along the transmission direction of the support and transmission device 201.

[0042] The electrochemically vibrated cleaning device includes an electrochemically vibrated cleaning tank 301, an electrochemically cleaning solution 302, an ultrasonic vibrator 306, a voltage and current control component, and an electrochemically cleaning solution replenishment and recovery component. The electrochemically cleaning solution 302 is placed in the electrochemically vibrated cleaning tank 301, the ultrasonic vibrator 306 is arranged on the electrochemically vibrated cleaning tank 301, the voltage and current control component is installed in the electrochemically vibrated cleaning tank 301 to control the current density passing through the stainless steel materials, and the electrochemically cleaning solution replenishment and recovery component is connected to the electrochemically vibrated cleaning tank 301. The voltage and current control component, the ultrasonic vibrator 306, and the electrochemically vibrated cleaning tank 301 can be integrally designed and manufactured, or a split design can be adopted. The electrochemically cleaning solution 302 includes an H2SO4 solution with a mass fraction of 1% to 40%. The electrochemically cleaning solution replenishment and recovery component includes an electrochemically cleaning solution recovery, treatment, and replenishment tank 307, and a replenishment cleaning solution 308 is placed in the electrochemically cleaning solution recovery, treatment, and replenishment tank 307. The electrochemically cleaning solution recovery, treatment, and replenishment tank 307 is connected to the electrochemically vibrated cleaning tank 301 through a liquid supply pipeline and a recovery pipeline. The voltage and current control component includes voltage loading modules 303, 304, and a current monitoring module 305. The voltage loading modules 303, 304 apply a voltage to the stainless steel materials, and the current monitoring module 305 monitors the current density passing through the stainless steel materials. The voltage and current control component can automatically adjust the applied voltage and current, and ensure that the current density passing through the stainless steel sample to be cleaned remains within the optimal electrochemically vibrated cleaning current density range. Moreover, the ultrasonic vibration system can adjust the amplitude and frequency according to the solution volume and parameter settings in the electrochemically cleaning tank. The electrochemically cleaning solution replenishment and recovery component can replenish the electrochemically cleaning solution 302 in the electrochemically vibrated cleaning tank 301 after monitoring that the concentration of the electrochemically cleaning solution 302 is lower than a specific value, and can simultaneously recover and treat the waste liquid of the low-concentration electrochemically cleaning solution 302.

[0043] The spray cleaning device includes a spray cleaning tank 401 and cleaning nozzles 403. The cleaning nozzles 403 are distributed on the top and bottom of the spray cleaning tank 401 and are used to spray both sides of the stainless steel material. The spray cleaning solution 402 in the spray cleaning device includes a NaHCO3 solution with a mass fraction of 1% - 10% or clean water.

[0044] The air-blowing drying device includes an air-blowing drying box 501 and air-blowing fans 502. The air-blowing fans 502 are distributed on the top and bottom of the air-blowing drying box 501 and are used to blow-dry both sides of the stainless steel material.

[0045] When batch removing the oxide layer on the surface of stainless steel strips, plates, wires, pipes and profiles, the support transmission device 201 can be used for automatic transmission. For the removal of the oxide layer on the surface of small or complex stainless steel workpieces, manual or robotic transfer can be used. The support transmission device can use a conveyor belt, and the conveyor belt runs through the electrochemical vibration cleaning device, the spray cleaning device, and the air-blowing drying device to form an automatic production line.

[0046] The system also includes a stainless steel material clamping and winding device. There are two groups of stainless steel material clamping and winding devices, numbered 101 and 601 in the figure, which are distributed at the head and tail ends of the transmission line of the support transmission device 201. When batch removing the oxide layer on the surface of stainless steel strips, plates, wires, pipes and profiles, the stainless steel material clamping and winding devices 101 and 601 can be used for clamping and winding. The stainless steel material clamping and winding devices 101 and 601 are existing mechanical components.

[0047] As Figure 2 shown, the present invention also provides an efficient and environmentally friendly low-temperature cleaning method for stainless steel oxide layers. This method is based on the above-mentioned efficient and environmentally friendly low-temperature cleaning system for stainless steel oxide layers, and this method includes the following main steps:

[0048] S1. Prepare an H2SO4 solution with a mass fraction of 1% - 40% as the electrochemical vibration cleaning solution;

[0049] S2. Place the stainless steel material to be cleaned in the electrochemical vibration cleaning tank 301, add the prepared electrochemical vibration cleaning solution, and turn on the ultrasonic vibrator 306;

[0050] S3. Apply a voltage to the stainless steel material and monitor the current density passing through the stainless steel material;

[0051] S4. After the electrochemical vibration cleaning is completed, spray and clean the stainless steel material with a NaHCO3 solution with a mass fraction of 1% - 10% or clean water to remove the residual sulfuric acid solution on the surface of the stainless steel material;

[0052] S5. Perform air-blowing drying treatment on the spray-cleaned stainless steel material;

[0053] S6. The stainless steel materials after coiling, encapsulating and cleaning are obtained.

[0054] In the above process, to improve the cleaning efficiency and reduce the concentration of the H2SO4 solution at the same time, the mass fraction of the cleaning solution should be controlled at 2% - 15%.

[0055] A voltage of 0.5 - 24 V is applied to the stainless steel materials to ensure that the current density passing through the stainless steel to be cleaned is 1 - 300 mA·cm -2 , and under the above conditions, the stainless steel materials to be cleaned are subjected to electro - chemical vibration cleaning for 0.5 - 30 min.

[0056] In another preferred embodiment, to improve the cleaning efficiency and reduce the energy consumption during the cleaning process, the voltage applied by the voltage loading system to the stainless steel materials to be cleaned should be controlled at 1 - 12 V to ensure that the current density passing through the stainless steel to be cleaned is 10 - 200 mA·cm -2 , and under the above conditions, the stainless steel materials to be cleaned are subjected to electro - chemical vibration cleaning for 1 - 10 min.

[0057] When the mass fraction of H2SO4 in the electro - chemical vibration cleaning solution is lower than 1%, or the total mass fraction of Fe 2+ 、Fe 3+ is higher than 2%, the solution in the electro - chemical vibration cleaning tank 301 is recycled, the contents of H2SO4 and Fe 2+ 、Fe 3+ in the solution are adjusted, and the electro - chemical vibration cleaning solution in the electro - chemical vibration cleaning tank 301 is supplemented.

[0058] In step S5, a blast drying device is used to blast - dry the stainless steel materials after spray cleaning, and the temperature and wind speed in the blast drying device can be automatically adjusted according to the requirements of the materials to be cleaned.

[0059] The following are several specific examples of cleaning using the high - efficiency and environmentally friendly low - temperature cleaning system for stainless steel oxide layers of the present invention:

[0060] Example 1:

[0061] (1) Prepare a sulfuric acid solution with a mass fraction of 4.76% as the electro - chemical vibration cleaning solution, and add the cleaning solution with a volume approximately three - quarters of that of the electro - chemical vibration cleaning tank 301 into the cleaning tank;

[0062] (2) Place the SS316L stainless steel thin plate heated to 900 °C and held for 5 min in the furnace into the electro - chemical vibration cleaning tank 301, and turn on the ultrasonic vibration system;

[0063] (3) Turn on the voltage loading system, apply a voltage of 2.0 V to the SS316L stainless steel thin plate to be cleaned, and ensure that the current density flowing through the SS316L stainless steel thin plate is 90 - 130 mA·cm -2 , and vibrate and clean for 2 min under this condition;

[0064] (4) After the electrochemical vibration cleaning is completed, rinse the SS316L stainless steel thin plate with deionized water;

[0065] (5) Use a blast drying system to dry the cleaned SS316L stainless steel thin plate and store it in a sealed plastic bag.

[0066] (6) Use a three-dimensional microscope to measure the surface roughness of the cleaned SS316L stainless steel thin plate, and the results are shown in Table 1 in the appendix.

[0067] Example 2:

[0068] (1) Prepare a sulfuric acid solution with a mass fraction of 4.76% as the electrochemical vibration cleaning solution, and add the cleaning solution with a volume of about three-quarters of the electrochemical vibration cleaning tank 301 to the cleaning tank;

[0069] (2) Place the SS316L stainless steel thin plate heated to 900 °C and held for 5 min in the furnace into the electrochemical vibration cleaning tank 301, and turn on the ultrasonic vibration system;

[0070] (3) Turn on the voltage loading system, apply a voltage of 2.0 V to the SS316L stainless steel thin plate to be cleaned, and ensure that the current density flowing through the SS316L stainless steel thin plate is 90 - 130 mA·cm -2 , and vibrate and clean for 3 min under this condition;

[0071] (4) After the electrochemical vibration cleaning is completed, rinse the SS316L stainless steel thin plate with deionized water;

[0072] (5) Use a blast drying system to dry the cleaned SS316L stainless steel thin plate and store it in a sealed plastic bag.

[0073] (6) Use a three-dimensional microscope to measure the surface roughness of the cleaned SS316L stainless steel thin plate, and the results are shown in Table 1 in the appendix.

[0074] Example 3:

[0075] (1) Prepare a sulfuric acid solution with a mass fraction of 4.76% as the electrochemical vibration cleaning solution, and add the cleaning solution with a volume of about three-quarters of the electrochemical vibration cleaning tank 301 to the cleaning tank;

[0076] (2) Place the SS316L stainless steel thin plate heated to 900 °C and held for 5 min in the furnace into the electrochemical vibration cleaning tank 301, and turn on the ultrasonic vibration system;

[0077] (3) Turn on the voltage loading system, apply a voltage of 2.0 V to the SS316L stainless steel thin plate to be cleaned, and ensure that the current density flowing through the SS316L stainless steel thin plate is 90 - 130 mA·cm -2 , and perform vibration cleaning for 5 min under this condition;

[0078] (4) After the electrochemical vibration cleaning is completed, rinse the SS316L stainless steel thin plate with deionized water;

[0079] (5) Use the air-blowing drying system to dry the cleaned SS316L stainless steel thin plate, and store it in a sealed plastic bag.

[0080] (6) Use a three-dimensional microscope to measure the surface roughness of the cleaned SS316L stainless steel thin plate, and the results are shown in Table 1 in the appendix.

[0081] Example 4:

[0082] (1) Prepare a sulfuric acid solution with a mass fraction of 4.76% as the electrochemical vibration cleaning solution, and add about three-quarters of the cleaning solution by volume of the electrochemical vibration cleaning tank 301 to the cleaning tank;

[0083] (2) Place the original SS316L stainless steel thin plate into the electrochemical vibration cleaning tank 301, and turn on the ultrasonic vibration system;

[0084] (3) Turn on the voltage loading system, apply a voltage of 2.0 V to the SS316L stainless steel thin plate to be cleaned for the first electrochemical vibration cleaning, and ensure that the current density flowing through the SS316L stainless steel thin plate is 90 - 130 mA·cm -2 , and perform vibration cleaning for 3 min under this condition;

[0085] (4) After the first electrochemical vibration cleaning is completed, replace the cleaning solution with a newly prepared sulfuric acid solution with a mass fraction of 4.76% for the second electrochemical vibration cleaning, apply 2.0 V to the SS316L stainless steel thin plate to be cleaned, and ensure that the current density flowing through the SS316L stainless steel thin plate is 90 - 130 mA·cm -2 , and perform vibration cleaning for 2 min under this condition;

[0086] (5) After the second electrochemical vibration cleaning is completed, rinse the SS316L stainless steel thin plate with deionized water;

[0087] (6) Use a blast drying system to dry the cleaned SS316L stainless steel thin plate and store it in a sealed plastic bag;

[0088] (7) Use a three-dimensional microscope to measure the surface roughness of the cleaned SS316L stainless steel thin plate, and the results are shown in Table 1;

[0089] (8) Use a three-electrode electrochemical workstation to test the corrosion resistance of the cleaned SS316L stainless steel thin plate, and the results are as Figure 3 shown.

[0090] Example 5:

[0091] (1) Prepare a sulfuric acid solution with a mass fraction of 4.76% as the electrochemical vibration cleaning solution, and add about three-quarters of the cleaning solution to the cleaning tank of the electrochemical vibration cleaning tank 301;

[0092] (2) Place the SS316L stainless steel thin plate heated and kept at 750 °C for 30 min in the electrochemical vibration cleaning tank 301, and turn on the ultrasonic vibration system;

[0093] (3) Turn on the voltage loading system, apply a voltage of 2.0 V to the SS316L stainless steel thin plate to be cleaned for the first electrochemical vibration cleaning, and ensure that the current density flowing through the SS316L stainless steel thin plate is 90 - 130 mA·cm -2 , and vibrate and clean for 3 min under this condition;

[0094] (4) After the first electrochemical vibration cleaning is completed, replace the cleaning solution with a newly prepared sulfuric acid solution with a mass fraction of 4.76% for the second electrochemical vibration cleaning. Apply 2.0 V to the SS316L stainless steel thin plate to be cleaned, and ensure that the current density flowing through the SS316L stainless steel thin plate is 90 - 130 mA·cm -2 , and vibrate and clean for 2 min under this condition;

[0095] (5) After the second electrochemical vibration cleaning is completed, rinse the SS316L stainless steel thin plate with deionized water;

[0096] (6) Use a blast drying system to dry the cleaned SS316L stainless steel thin plate and store it in a sealed plastic bag;

[0097] (7) Use a three-dimensional microscope to measure the surface roughness of the cleaned SS316L stainless steel thin plate, and the results are shown in Table 1;

[0098] (8) Use a three-electrode electrochemical workstation to test the corrosion resistance of the cleaned SS316L stainless steel thin plate, and the results are as Figure 3 shown.

[0099] Example 6:

[0100] (1) Prepare a sulfuric acid solution with a mass fraction of 4.76% as the electrochemically vibrated cleaning solution, and add the cleaning solution with a volume approximately three - quarters of the electrochemically vibrated cleaning tank 301 to the cleaning tank;

[0101] (2) Place the SS316L stainless steel thin plate heated and kept at 800 °C for 30 min in the electrochemically vibrated cleaning tank 301, and turn on the ultrasonic vibration system;

[0102] (3) Turn on the voltage loading system, apply a voltage of 2.0 V to the SS316L stainless steel thin plate to be cleaned for the first electrochemically vibrated cleaning, ensuring that the current density flowing through the SS316L stainless steel thin plate is 90 - 130 mA·cm -2 , and vibrate and clean for 3 min under this condition;

[0103] (4) After the first electrochemically vibrated cleaning is completed, replace the cleaning solution with a newly prepared sulfuric acid solution with a mass fraction of 4.76% for the second electrochemically vibrated cleaning. Apply 2.0 V to the SS316L stainless steel thin plate to be cleaned, ensuring that the current density flowing through the SS316L stainless steel thin plate is 90 - 130 mA·cm -2 , and vibrate and clean for 2 min under this condition;

[0104] (5) After the second electrochemically vibrated cleaning is completed, rinse the SS316L stainless steel thin plate with deionized water;

[0105] (6) Use a blast drying system to dry the cleaned SS316L stainless steel thin plate and store it in a sealed plastic bag;

[0106] (7) Use a three - dimensional microscope to measure the surface roughness of the cleaned SS316L stainless steel thin plate, and the results are shown in Table 1 in the appendix;

[0107] (8) Use a three - electrode electrochemical workstation to test the corrosion resistance of the cleaned SS316L stainless steel thin plate, and the results are as Figure 3 shown.

[0108] Example 7:

[0109] (1) Prepare a sulfuric acid solution with a mass fraction of 4.76% as the electrochemically vibrated cleaning solution, and add the cleaning solution with a volume approximately three - quarters of the electrochemically vibrated cleaning tank 301 to the cleaning tank;

[0110] (2) Place the SS316L stainless steel thin plate heated and kept at 850 °C for 30 min in the electrochemically vibrated cleaning tank 301, and turn on the ultrasonic vibration system;

[0111] (3) Turn on the voltage loading system, apply a voltage of 2.0 V to the SS316L stainless steel thin plate to be cleaned for the first electrochemical vibration cleaning, and ensure that the current density flowing through the SS316L stainless steel thin plate is 90 - 130 mA·cm -2 , and perform vibration cleaning for 3 min under this condition;

[0112] (4) After the first electrochemical vibration cleaning is completed, replace the cleaning solution with a newly prepared sulfuric acid solution with a mass fraction of 4.76% for the second electrochemical vibration cleaning. Apply 2.0 V to the SS316L stainless steel thin plate to be cleaned, and ensure that the current density flowing through the SS316L stainless steel thin plate is 90 - 130 mA·cm -2 , and perform vibration cleaning for 2 min under this condition;

[0113] (5) After the second electrochemical vibration cleaning is completed, rinse the SS316L stainless steel thin plate with deionized water;

[0114] (6) Use a blast drying system to dry the cleaned SS316L stainless steel thin plate and store it in a sealed plastic bag;

[0115] (7) Use a three-dimensional microscope to measure the surface roughness of the cleaned SS316L stainless steel thin plate, and the results are shown in Table 1 in the appendix;

[0116] (8) Use a three-electrode electrochemical workstation to test the corrosion resistance of the cleaned SS316L stainless steel thin plate, and the results are as Figure 3 shown.

[0117] Example 8:

[0118] (1) Prepare a sulfuric acid solution with a mass fraction of 4.76% as the electrochemical vibration cleaning solution, and add the cleaning solution with a volume approximately three-quarters of the electrochemical vibration cleaning tank 301 to the cleaning tank;

[0119] (2) Place the SS316L stainless steel thin plate heated and kept at 900 °C for 30 min in the electrochemical vibration cleaning tank 301, and turn on the ultrasonic vibration system;

[0120] (3) Turn on the voltage loading system, apply a voltage of 2.0 V to the SS316L stainless steel thin plate to be cleaned for the first electrochemical vibration cleaning, and ensure that the current density flowing through the SS316L stainless steel thin plate is 90 - 130 mA·cm -2 , and perform vibration cleaning for 3 min under this condition;

[0121] (4) After the first electrochemical vibration cleaning is completed, replace the cleaning solution with a newly prepared sulfuric acid solution with a mass fraction of 4.76% for the second electrochemical vibration cleaning. Apply 2.0 V to the SS316L stainless steel sheet to be cleaned, and ensure that the current density flowing through the SS316L stainless steel sheet is 90 - 130 mA·cm -2 , and perform vibration cleaning for 2 min under this condition;

[0122] (5) After the second electrochemical vibration cleaning is completed, rinse the SS316L stainless steel sheet with deionized water;

[0123] (6) Use a blast drying system to dry the cleaned SS316L stainless steel sheet and store it in a sealed plastic bag;

[0124] (7) Use a three-dimensional microscope to measure the surface roughness of the cleaned SS316L stainless steel sheet, and the results are shown in Table 1 in the appendix;

[0125] (8) Use a three-electrode electrochemical workstation to test the corrosion resistance of the cleaned SS316L stainless steel sheet, and the results are as Figure 3 shown.

[0126] Example 9:

[0127] (1) Place the original SS316L stainless steel sample in an alcohol solution and perform ultrasonic vibration cleaning for 5 min;

[0128] (2) Use a blast drying system to dry the cleaned SS316L stainless steel material and store it in a sealed plastic bag;

[0129] (3) Use a three-dimensional microscope to measure the surface roughness of the cleaned SS316L stainless steel material, and the results are shown in Table 1 in the appendix.

[0130] (4) Use a three-electrode electrochemical workstation to test the corrosion resistance of the cleaned SS316L stainless steel, and the results are as Figure 3 shown.

[0131] Example 10:

[0132] (1) Place the SS316L stainless steel sheet heated and held at 900 °C for 30 min in an alcohol solution and perform ultrasonic vibration cleaning for 5 min;

[0133] (2) Use a blast drying system to dry the cleaned SS316L stainless steel sheet and store it in a sealed plastic bag;

[0134] (3) Use a three-dimensional microscope to measure the surface roughness of the cleaned SS316L stainless steel sheet, and the results are shown in Table 1 in the appendix.

[0135] (4) The corrosion resistance of the cleaned SS316L stainless steel sheet was tested using a three-electrode electrochemical workstation, and the results are as Figure 3 shown.

[0136] Table 1 Surface quality of the SS316L stainless steel oxide layer under different cleaning conditions

[0137]

[0138]

[0139] The smaller the surface roughness, the higher the surface quality of the stainless steel. After cleaning under appropriate electrochemical cleaning processes and parameter conditions, the surface roughness of the stainless steel is smaller and the quality is higher. The data in Table 1 show that when directly cleaning with sulfuric acid at the said concentration without the electrochemical vibration process, the oxide layer cannot be removed and the roughness remains basically unchanged; when cleaning with sulfuric acid at the said concentration in the present invention with only electrochemistry without vibration, there are still a large number of visible oxide layers on the surface after cleaning. Therefore, the combination of electrochemistry and vibration in the present invention can greatly improve the cleaning quality.

[0140] The above embodiments are only examples and do not represent limitations on the scope of the present invention. These embodiments can also be implemented in various other ways and various omissions, substitutions, and changes can be made without departing from the technical idea of the present invention.

Claims

1. An efficient and environmentally friendly low-temperature cleaning method for stainless steel oxide layer, characterized in that, An efficient and environmentally friendly low-temperature cleaning system for stainless steel oxide layer is adopted, and the method includes: S1. Prepare an H2SO4 solution with a mass fraction of 1% - 40% as the electrochemical vibration cleaning solution; S2. Place the stainless steel material to be cleaned in the electrochemical vibration cleaning tank (301), add the prepared electrochemical vibration cleaning solution, and turn on the ultrasonic vibrator (306); S3. Apply a voltage to the stainless steel material and monitor the current density passing through the stainless steel material; S4. After the electrochemical vibration cleaning is completed, spray and clean the stainless steel material with a NaHCO3 solution with a mass fraction of 1% - 10% or clean water to remove the residual sulfuric acid solution on the surface of the stainless steel material; S5. Perform air-blowing drying treatment on the stainless steel material after spray cleaning; S6. Roll up and package the cleaned stainless steel material; When the mass fraction of H2SO4 in the electrochemically vibrated cleaning solution is less than 1%, or the total mass fraction of Fe 2+ and Fe 3+ is higher than 2%, the solution in the electrochemically vibrated cleaning tank (301) is recycled, the contents of H2SO4 and Fe 2+ and Fe 3+ in the solution are adjusted, and the electrochemically vibrated cleaning solution in the electrochemically vibrated cleaning tank (301) is replenished; The system includes: An electrochemical vibration cleaning device for performing electrochemical vibration cleaning on stainless steel materials; A spray cleaning device for spray cleaning the stainless steel material after electrochemical vibration cleaning; An air-blowing drying device for drying the stainless steel material after spray cleaning; A support and transmission device (201) for supporting and transmitting the stainless steel material, and the electrochemical vibration cleaning device, the spray cleaning device, and the air-blowing drying device are arranged in sequence along the transmission direction of the support and transmission device (201); the electrochemical vibration cleaning device includes an electrochemical vibration cleaning tank (301), an electrochemical cleaning solution (302), an ultrasonic vibrator (306), a voltage and current control component, and an electrochemical cleaning solution replenishment and recovery component. The electrochemical cleaning solution (302) is placed in the electrochemical vibration cleaning tank (301), the ultrasonic vibrator (306) is arranged on the electrochemical vibration cleaning tank (301), the voltage and current control component is installed in the electrochemical vibration cleaning tank (301) to control the current density passing through the stainless steel material, and the electrochemical cleaning solution replenishment and recovery component is connected to the electrochemical vibration cleaning tank (301); the electrochemical cleaning solution replenishment and recovery component includes an electrochemical cleaning solution recovery, treatment, and replenishment tank (307), and a replenishment cleaning solution (308) is placed in the electrochemical cleaning solution recovery, treatment, and replenishment tank (307). The electrochemical cleaning solution recovery, treatment, and replenishment tank (307) is connected to the electrochemical vibration cleaning tank (301) through a liquid supply pipeline and a recovery pipeline.

2. An efficient and environmentally friendly low-temperature cleaning method for stainless steel oxide layers according to claim 1, characterized in that, The spray cleaning device includes a spray cleaning tank (401) and cleaning nozzles (403), and the cleaning nozzles (403) are distributed on the top and bottom of the spray cleaning tank (401) for spraying both the front and back sides of the stainless steel material.

3. An efficient and environmentally friendly low-temperature cleaning method for stainless steel oxide layer according to claim 1, characterized in that, The air-blowing drying device includes an air-blowing drying box (501) and air-blowing fans (502), and the air-blowing fans (502) are distributed on the top and bottom of the air-blowing drying box (501) for air-blowing drying both the front and back sides of the stainless steel material.

4. An efficient and environmentally friendly low-temperature cleaning method for stainless steel oxide layer according to claim 1, characterized in that, The electrochemical cleaning solution (302) includes an H2SO4 solution with a mass fraction of 1% - 40%.

5. An efficient and environmentally friendly low-temperature cleaning method for stainless steel oxide layers according to claim 1, characterized in that, In the described spray cleaning device, the spray cleaning solution (402) includes a NaHCO₃ solution with a mass fraction of 1% - 10% or clean water.

6. An efficient and environmentally friendly low-temperature cleaning method for stainless steel oxide layer according to claim 1, characterized in that, The system further includes a stainless steel material clamping and winding device. Two sets of the stainless steel material clamping and winding devices are provided and distributed at the head and tail ends of the transmission line of the support transmission device (201).

Images