A method for optimizing the alkali pickling surface of titanium plate

Abstract

The invention discloses a method for optimizing the surface of a titanium plate by alkali pickling, comprising the following steps: S1, framing; S2, alkali washing; S3, water washing; S4, material lifting and stringing; S5, pickling; S6, washing with dilute sulfuric acid. The invention provides a method for optimizing the surface of a titanium plate by alkali pickling. By optimizing the contact mode between a titanium alloy plate and a pickled titanium rod and combining the method of adding a material lifting and stringing during the pickling process, the obvious color difference caused by uneven liquid reception at the contact part between the plate and the titanium rod in the process, commonly known as the rod print in the industry, is effectively eliminated. The titanium rod is spot welded to change the contact mode between the titanium rod and the titanium alloy plate from line contact to point contact, which can reduce the generation of the rod print to a certain extent. Adding a material lifting and stringing during the pickling process can effectively improve the plate surface color difference caused by uneven corrosion rate at the contact part between the titanium alloy plate and the titanium rod.

Description

Technical Field

[0001] The invention relates to the field of metal material surface treatment, in particular to a method for optimizing the alkali pickling surface of a titanium plate. Background Art

[0002] Titanium and titanium alloy plates have the characteristics of high specific strength, high specific modulus, good corrosion resistance and good creep resistance, and have become the preferred materials in the aerospace field. In recent years, with the rapid development of economy and technology and the steady progress of aerospace industry, the requirements for the comprehensive performance of titanium alloy materials have also increased. Titanium alloy plates are very easy to form a dense oxide layer on the surface after heat treatment. The oxide layer will not only affect the process performance of the material, but also affect subsequent welding and other processes. Therefore, in order to remove the oxide layer on the surface of the material and obtain a smooth surface, the commonly used methods are sandblasting, alkaline pickling, grinding and polishing, and laser cleaning. Alkaline pickling Due to its high production efficiency and stable surface quality, it is widely used in the industrial production of titanium alloy plates. Most of the current alkaline pickling processes can thoroughly clean the surface oxide scale and effectively improve the surface over-acid phenomenon. However, during the alkaline pickling process, it is inevitable that the corrosion rate of the titanium alloy plate at the contact point between the titanium rod and the plate is inconsistent with that of other places, resulting in obvious color difference on the surface of the plate after alkaline pickling, that is, vertical marks, commonly known as rod marks in the industry, and the faster the pickling reaction speed and the longer the pickling time, the more obvious the rod marks will be. Therefore, for finished plates, it is very necessary to eliminate the rod marks in the alkaline pickling process.

[0003] Pangang Group Jiangyou Great Wall Special Steel Co., Ltd. proposed an alkaline pickling method for titanium alloy in its invention with publication number CN101709474A, which mainly involves 1 to 3 alkaline washing and water washing, then pickling, passivation and whitening, and during the passivation and whitening process, by controlling the concentration of Fe2+ / Fe3+ in the solution, the oxide scale on the surface of the titanium alloy after alkaline pickling is completely washed away, the surface is grayish white, and the surface quality is good.

[0004] Baoji Huaye Titanium Nickel Metal Co., Ltd. proposed a titanium plate alkaline pickling method including alkaline washing, water washing, acid washing and alkaline pickling in an invention with publication number CN109306494A. The alkaline molten liquid is composed of a mixture of 95-98% sodium hydroxide and 2-5% sodium nitrate by weight, and the acid solution is composed of a mixture of 25-33% nitric acid and 67-75% water by weight. This method can effectively improve the over-acid phenomenon on the surface of titanium alloy after alkaline pickling.

[0005] In summary, from the existing technical data, the surface quality of titanium alloy after alkali pickling can be improved by controlling the process, temperature, concentration and time of alkali pickling. However, the alkali pickling process of titanium alloy plates still has the following problems to be solved:

[0006] Titanium alloy sheet production adopts framed alkaline pickling, and titanium plates are separated by titanium rods. During pickling, the corrosion rate of the contact position between the titanium plate and the titanium rod is inconsistent with that of other places, resulting in rod marks on the plate after pickling;

[0007] After pickling, the titanium alloy plate is directly washed with clean water and dried. Incomplete cleaning will cause residual acid to form acid stains on the surface of the plate. Incomplete drying will cause acid reflux due to moisture during subsequent storage and transportation.

[0008] Therefore, it is necessary to provide a method for optimizing the alkali pickling surface of titanium plates to solve the above technical problems. Summary of the invention

[0009] The invention provides a method for optimizing the alkali pickling surface of a titanium plate, which solves the problem of plate surface color difference caused by uneven liquid reception at the contact part between the plate and the titanium rod in the process.

[0010] In order to solve the above technical problems, the present invention provides a method for optimizing the alkali pickling surface of a titanium plate, comprising the following steps:

[0011] S1. Frame loading: whiten the surface of the finished plate, load the titanium alloy plate into the alkali-acid washing frame, and load one titanium alloy plate into each grid of the alkali-acid washing frame, with the spacing between each grid not less than 100 mm;

[0012] S2, alkali washing: after the titanium alloy plate inside the alkali pickling material frame in S1 is installed, the titanium alloy plate is immersed in an alkali melt at 470-490° C., wherein the alkali melt is composed of a mixture of 7-12% sodium nitrate and 88-93% sodium hydroxide by weight, and the alkali washing time is 1-30 minutes;

[0013] S3, water washing: immersing the titanium alloy plate after alkali washing in S2 in a water tank at room temperature, and washing the alkali melt on the surface of the titanium alloy plate with water;

[0014] S4, lifting and stringing: adjust the lifting frame of the titanium alloy plate washed with water in S3, and move the titanium alloy plate in the alkali-acid washing frame by about the position of a titanium rod, so as to avoid the color difference of the plate surface caused by the uneven corrosion rate of the contact part between the titanium alloy plate and the titanium rod in this process;

[0015] S5, pickling: soaking the washed and stripped titanium alloy plate in an acidic solution containing 2-5% hydrofluoric acid and 20-40% nitric acid with the remainder being water, the pickling time being 1-3 minutes;

[0016] S6. Washing with dilute sulfuric acid: Soak the pickled titanium alloy plate in a dilute sulfuric acid aqueous solution with a concentration of 20% and a temperature below 40°C for no more than 2 minutes. Rinse the titanium alloy plate that has passed through the dilute sulfuric acid tank with water to remove the acid marks remaining on the surface. Use a clean cloth to wipe off the alkali and acid on the top of the alkaline pickling frame to prevent alkali and acid dripping from contaminating the surface of the titanium alloy plate. Then dry it and remove the frame.

[0017] Preferably, the alkali pickling material frame in S1 can be divided into 1 to 3 rows of frames per grid according to the actual size of different plates. The pickled titanium rod is spot welded to change the contact mode between the titanium alloy plate and the titanium rod from line contact to point contact, which can reduce the generation of rod marks to a certain extent.

[0018] Preferably, in S2, no alkali washing is performed on medium and thick plates and titanium alloy plates such as TB5 and Ti230 that are easy to absorb hydrogen.

[0019] Preferably, the titanium alloy plate 2 after pickling in S5 is pickled for the second time according to S5, so as to be applicable to the situation where the thickness of the titanium alloy plate does not meet the requirements. The titanium alloy plate after the second pickling according to S5 can also be pickled for the third time according to S5, so as to be applicable to the situation where the thickness of the titanium alloy plate still does not meet the requirements. Before each pickling, the material lifting and stringing step must be performed.

[0020] Preferably, in said S6, the pickled titanium alloy plate is washed with dilute sulfuric acid to pre-neutralize the residual acid attached to the surface, so as to avoid acid reflux on the surface of the titanium alloy plate due to incomplete washing during direct water washing.

[0021] Preferably, the wiping of the alkali pickling material frame and the drying of the titanium alloy plate in S6 requires the use of a processing device, the processing device includes a workbench, three sets of conveyor belts are installed on the surface of the workbench, a drying hood is installed at the center of the surface of the workbench, an adjusting device is provided on one side of the top of the drying hood, a wiping assembly is provided at one end of the adjusting device, the wiping assembly includes a U-shaped fixing frame, wiping cotton is bonded to both sides and the top of the inner wall of the U-shaped fixing frame, dryers are installed on both sides and the top of the inner wall of the drying hood, and a controller is installed on the top of the drying hood.

[0022] Preferably, the adjusting device comprises a hydraulic telescopic rod, the top end of the hydraulic telescopic rod is connected to a connecting frame, and one end of the connecting frame is connected to the center position of the surface of the U-shaped fixing frame.

[0023] Preferably, movable components are provided on both sides of the drying hood, and the movable components include two movable plates. The surface of the drying hood is provided with movable through grooves adapted to the movable plates.

[0024] Preferably, a limiting device is provided on the surface of the workbench and above the conveyor belt, the limiting device comprises a double-headed hydraulic telescopic rod, both ends of the double-headed hydraulic telescopic rod are connected to movable rods via connecting blocks, the opposite ends of the two movable rods are connected to limiting plates, a fixing ring is installed at the center position of the surface of the double-headed hydraulic telescopic rod, and the fixing ring is connected to the bottom of the workbench via a connecting block.

[0025] Preferably, a disassembly assembly is provided between the connecting frame and the U-shaped fixing frame, the disassembly assembly includes a disassembly sleeve, a disassembly block is provided inside the disassembly sleeve, one end of the disassembly block is connected to one end of the connecting frame, and a bolt is provided between the disassembly sleeve and the disassembly block.

[0026] Compared with the related art, the method for optimizing the alkali pickling surface of titanium plate provided by the present invention has the following beneficial effects:

[0027] The present invention provides a method for optimizing the alkali pickling surface of a titanium plate, which can effectively eliminate the generation of rod marks on the surface of the titanium alloy plate by optimizing the contact mode between the titanium alloy plate and the titanium rod, changing the line contact to point contact.

[0028] By adding the material lifting and stringing method in the pickling process, the color difference of the plate surface caused by the uneven corrosion rate of the contact part between the titanium alloy plate and the titanium rod in the process is further eliminated;

[0029] The residual acid attached to the surface of the titanium alloy plate after pickling is pre-neutralized with dilute sulfuric acid to avoid the formation of acid stains due to incomplete washing during direct water washing. The residual acid marks on the surface are then rinsed with water to avoid acid back phenomenon.

[0030] This method is suitable for titanium alloy plates of different specifications and different surface conditions, and is suitable for batch and engineering treatment of the surface quality of titanium alloy plates. The invention content clarifies the detailed parameters such as the ratio, temperature, time, method, etc. in the alkaline acid pickling process. It is easy to operate and has strong practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 A schematic structural diagram of a first embodiment of a method for optimizing the alkaline pickling surface of a titanium plate provided by the present invention;

[0032] Figure 2 A schematic structural diagram of a second embodiment of a method for optimizing the alkali pickling surface of a titanium plate provided by the present invention;

[0033] Figure 3 for Figure 2 An enlarged schematic diagram of part A is shown;

[0034] Figure 4 for Figure 2 An enlarged schematic diagram of part B is shown;

[0035] Figure 5 for Figure 2 An enlarged schematic diagram of part C is shown;

[0036] Figure 6 for Figure 2 A schematic diagram of the overall three-dimensional structure of the device shown;

[0037] Figure 7 A schematic structural diagram of a third embodiment of a method for optimizing the alkaline pickling surface of a titanium plate provided by the present invention.

[0038] Numbers in the figure: 1. Alkali pickling material frame; 2. Titanium alloy plate; 3. Workbench; 4. Conveyor belt;

[0039] 5. Adjustment device; 51. Hydraulic telescopic rod; 52. Connecting frame;

[0040] 6. Wiping assembly; 61. U-shaped fixing frame; 62. Wiping cotton;

[0041] 7. Drying hood; 8. Dryer; 9. Controller;

[0042] 10. Limiting device; 101. Double-head hydraulic telescopic rod; 102. Movable rod; 103. Limiting plate; 104. Fixed ring;

[0043] 11. Disassembly assembly; 111. Disassembly sleeve; 112. Disassembly block; 113. Bolt;

[0044] 12. Titanium rod;

[0045] 13. movable assembly; 131. movable plate; 132. movable through slot. DETAILED DESCRIPTION

[0046] The present invention will be further described below in conjunction with the accompanying drawings and implementation modes.

[0047] First embodiment

[0048] Please refer to Figure 1 ,in, Figure 1 A schematic diagram of the structure of a first embodiment of a method for optimizing the alkali pickling surface of a titanium plate provided by the present invention. A method for optimizing the alkali pickling surface of a titanium plate comprises the following steps:

[0049] S1. Frame loading: whiten the surface of the finished plate, load the titanium alloy plate into the alkali-acid washing frame, and load one titanium alloy plate into each grid of the alkali-acid washing frame, with the spacing between each grid not less than 100 mm;

[0050] S2, alkali washing: after the titanium alloy plate inside the alkali pickling material frame in S1 is installed, the titanium alloy plate is immersed in an alkali melt at 470-490° C., wherein the alkali melt is composed of a mixture of 7-12% sodium nitrate and 88-93% sodium hydroxide by weight, and the alkali washing time is 1-30 minutes;

[0051] S3, water washing: immersing the titanium alloy plate after alkali washing in S2 in a water tank at room temperature, and washing the alkali melt on the surface of the titanium alloy plate with water;

[0052] S4, lifting and stringing: adjust the lifting frame of the titanium alloy plate washed with water in S3, and move the titanium alloy plate in the alkali-acid washing frame by about the position of a titanium rod, so as to avoid the color difference of the plate surface caused by the uneven corrosion rate of the contact part between the titanium alloy plate and the titanium rod in this process;

[0053] S5, pickling: soaking the washed and stripped titanium alloy plate in an acidic solution containing 2-5% hydrofluoric acid and 20-40% nitric acid with the remainder being water, the pickling time being 1-3 minutes;

[0054] S6. Washing with dilute sulfuric acid: Soak the pickled titanium alloy plate in a dilute sulfuric acid aqueous solution with a concentration of 20% and a temperature below 40°C for no more than 2 minutes. Rinse the titanium alloy plate that has passed through the dilute sulfuric acid tank with water to remove the acid marks remaining on the surface. Use a clean cloth to wipe off the alkali and acid on the top of the alkaline pickling frame to prevent alkali and acid dripping from contaminating the surface of the titanium alloy plate. Then dry it and remove the frame.

[0055] In S1, each grid of the alkali pickling material frame 1 can be divided into 1 to 3 rows of frames according to the actual size of different plates. The specific alkali pickling time is determined according to the grade, rolling method, surface quality and alkali solution concentration ratio of the titanium alloy plate.

[0056] The alkali pickling material frame in S1 can be divided into 1 to 3 rows of frames per grid according to the actual size of different plates. The pickled titanium rod is spot welded to change the contact mode between the titanium alloy plate and the titanium rod from line contact to point contact, which can reduce the generation of rod marks to a certain extent.

[0057] In the S2, the medium and thick plates and titanium alloy plates such as TB5 and Ti230 which are easy to absorb hydrogen are not subjected to alkali washing.

[0058] The titanium alloy plate 2 after pickling in S5 is pickled for the second time according to S5, which is suitable for the situation that the thickness of the titanium alloy plate does not meet the requirements. The titanium alloy plate after the second pickling according to S5 can also be pickled for the third time according to S5, which is suitable for the situation that the thickness of the titanium alloy plate still does not meet the requirements. Before each pickling, the material lifting and stringing step must be performed.

[0059] In S6, the pickled titanium alloy plate is washed with dilute sulfuric acid to pre-neutralize the residual acid attached to the surface, so as to avoid acid reflux on the surface of the titanium alloy plate caused by incomplete washing during direct water washing.

[0060] The titanium alloy used in the three groups of embodiments provided by the present invention is a Ti-6Al-4V alloy with a thickness of 1.0 mm and 6 mm and a TA15 alloy with a thickness of 1.0 mm (width 1000 mm, length 1000-2500 mm) obtained by rolling. The three types of plates are framed, alkali washed, water washed, material-lifted, pickled, and washed with dilute sulfuric acid, and the surfaces of the finished plates are finally obtained without rod marks.

[0061] Embodiment 1

[0062] The specific process of this embodiment is:

[0063] S1. Frame loading: The Ti-6Al-4V finished plate rolled to 1.0 mm thick (1000 mm wide × 2000 mm long) is subjected to surface whitening treatment, and the titanium alloy plate is loaded into the alkali pickling material frame, with one piece loaded in each grid, the spacing between each grid is 100 mm, and each grid is framed in 2 rows;

[0064] S2, alkali washing: immerse the material frame with Ti-6Al-4V titanium alloy plate in 450-480°C alkali melt, the alkali melt is composed of 8-10% sodium nitrate and 90-92% sodium hydroxide by weight, and the alkali washing time is 1-2 minutes, and the specific time depends on the surface quality;

[0065] S3, water washing: soaking the titanium alloy plate after alkali washing in a water tank at room temperature, and washing the alkali melt on the surface of the titanium alloy plate with water;

[0066] S4, lifting and positioning: adjust the lifting frame of the washed titanium alloy plate, and move the titanium alloy plate in the pickling frame by about one titanium rod to avoid the color difference of the plate surface caused by the uneven corrosion rate of the contact part between the titanium alloy plate and the titanium rod in this process;

[0067] S5. Pickling: The titanium alloy plate after water washing and material extraction is immersed in an acidic solution containing 3% hydrofluoric acid and 30-40% nitric acid and the balance is water, and the pickling time is 1-3 minutes;

[0068] S6. Washing with dilute sulfuric acid: Soak the pickled titanium alloy plate in a dilute sulfuric acid aqueous solution below 40°C and with a concentration of 20% for no more than 2 minutes. Rinse the titanium alloy plate that has passed through the dilute sulfuric acid tank with 60-90°C water to remove the acid marks remaining on the surface. Wipe off the alkali and acid on the top of the material frame with a clean cloth to prevent alkali and acid dripping from contaminating the surface of the plate. Dry it and then remove the frame.

[0069] The 1.0×1000×2000mm Ti-6Al-4V plate produced by the method of Example 1 has good surface quality, no rod marks, and no acid stains.

[0070] Embodiment 2

[0071] The specific process of this embodiment is:

[0072] S1. Frame loading: The Ti-6Al-4V finished plate rolled to 6.0 mm thick (1000 mm wide × 2500 mm long) is subjected to surface whitening treatment, and the titanium alloy plate is loaded into the alkali pickling material frame, with one piece per grid, the spacing between each grid is 130 mm, and each grid is framed in one row;

[0073] S2. Pickling: Soak the titanium alloy plate in an acidic solution containing 3% hydrofluoric acid and 30-40% nitric acid with the balance being water. The total pickling time shall not exceed 15 minutes, and each pickling time is 1-3 minutes;

[0074] If the thickness of the plate after pickling does not meet the requirements, carry out material lifting and repeating step 2; if the thickness of the plate after the second pickling still does not meet the requirements, continue to carry out material lifting and repeating step 2;

[0075] S3. Washing with dilute sulfuric acid: Soak the pickled titanium alloy plate in a dilute sulfuric acid aqueous solution below 40°C and with a concentration of 20% for no more than 2 minutes. Rinse the titanium alloy plate that has passed through the dilute sulfuric acid tank with 60-90°C water to remove the acid marks remaining on the surface. Wipe the alkali and acid on the top of the material frame with a clean cloth to prevent alkali and acid dripping from contaminating the surface of the plate. Dry it and then remove the frame.

[0076] The 6.0×1000×2500mm Ti-6Al-4V plate produced by the method of Example 2 has good surface quality, no rod marks, and no acid stains.

[0077] Embodiment 3

[0078] The specific process of this embodiment is:

[0079] S1. Frame loading: perform surface whitening treatment on the TA15 finished plate rolled to 1.0 mm thick (1000 mm wide × 2000 mm long), load the titanium alloy plate into the alkali pickling material frame, load one piece per grid, the spacing between each grid is 100 mm, and each grid is framed in 2 rows;

[0080] S2, alkali washing: immerse the material frame with TA15 titanium alloy plate in 450-480°C alkali melt, the alkali melt is composed of 7-10% sodium nitrate and 90-93% sodium hydroxide by weight, the alkali washing time is about 1-2 minutes, and the specific time depends on the surface quality;

[0081] S3, water washing: soaking the titanium alloy plate after alkali washing in a water tank at room temperature, and washing the alkali melt on the surface of the titanium alloy plate with water;

[0082] S4, lifting and positioning: adjust the lifting frame of the washed titanium alloy plate, and move the titanium alloy plate in the pickling frame by about one titanium rod to avoid the color difference of the plate surface caused by the uneven corrosion rate of the contact part between the titanium alloy plate and the titanium rod in this process;

[0083] S5. Pickling: Immerse the washed and stripped titanium alloy plate in an acidic solution containing 3-5% hydrofluoric acid and 40% nitric acid with the remainder being water, and the pickling time is 1-3 minutes;

[0084] S6. Washing with dilute sulfuric acid: Soak the pickled titanium alloy plate in a dilute sulfuric acid aqueous solution below 40°C and with a concentration of 20% for no more than 2 minutes. Rinse the titanium alloy plate that has passed through the dilute sulfuric acid tank with 60-90°C water to remove the acid marks remaining on the surface. Wipe off the alkali and acid on the top of the material frame with a clean cloth to prevent alkali and acid dripping from contaminating the surface of the plate. Dry it and then remove the frame.

[0085] The 1.0×1000×2000mm TA15 plate produced by the method of Example 3 has good surface quality, no rod marks, and no acid stains.

[0086] Compared with the related art, the method for optimizing the alkali pickling surface of titanium plate provided by the present invention has the following beneficial effects:

[0087] The present invention provides a method for optimizing the alkali pickling surface of a titanium plate, which can effectively eliminate the generation of rod marks on the surface of the titanium alloy plate by optimizing the contact mode between the titanium alloy plate and the titanium rod, changing the line contact to point contact.

[0088] By adding the material lifting and stringing method in the pickling process, the color difference of the plate surface caused by the uneven corrosion rate of the contact part between the titanium alloy plate and the titanium rod in the process is further eliminated;

[0089] The residual acid attached to the surface of the titanium alloy plate after pickling is pre-neutralized with dilute sulfuric acid to avoid the formation of acid stains due to incomplete washing during direct water washing. The residual acid marks on the surface are then rinsed with water to avoid acid back phenomenon.

[0090] This method is suitable for titanium alloy plates of different specifications and different surface conditions, and is suitable for batch and engineering treatment of the surface quality of titanium alloy plates. The invention content clarifies the detailed parameters such as the ratio, temperature, time, method, etc. in the alkaline acid pickling process. It is easy to operate and has strong practicality.

[0091] Second embodiment

[0092] Please refer to Figure 2 , Figure 3 , Figure 4 , Figure 5 and Figure 6 Based on the method for optimizing the alkali pickling surface of titanium plate provided by the first embodiment of the present application, the second embodiment of the present application proposes another method for optimizing the alkali pickling surface of titanium plate. The second embodiment is only a preferred method of the first embodiment, and the implementation of the second embodiment will not affect the independent implementation of the first embodiment.

[0093] Specifically, the second embodiment of the present application provides a method for optimizing the alkaline pickling surface of a titanium plate, which is different in that, in a method for optimizing the alkaline pickling surface of a titanium plate, a processing device is required to wipe the alkaline pickling material frame 1 and dry the titanium alloy plate 2 in S6, and the processing device includes a workbench 3, and three groups of conveyor belts 4 are installed on the surface of the workbench 3. A drying hood 7 is installed at the center position of the surface of the workbench 3, and an adjusting device 5 is provided on one side of the top of the drying hood 7. A wiping assembly 6 is provided at one end of the adjusting device 5, and the wiping assembly 6 includes a U-shaped fixing frame 61, and wiping cotton 62 is bonded to both sides and the top of the inner wall of the U-shaped fixing frame 61, and dryers 8 are installed on both sides and the top of the inner wall of the drying hood 7, and a controller 9 is installed on the top of the drying hood 7.

[0094] The adjusting device 5 comprises a hydraulic telescopic rod 51 , the top end of which is connected to a connecting frame 52 , and one end of the connecting frame 52 is connected to the center position of the surface of the U-shaped fixing frame 61 .

[0095] The hydraulic telescopic rod 51 is installed at the center position of one side of the top of the drying cover 7. The use of the hydraulic telescopic rod 51 facilitates the wiping assembly 6 to adjust the upper and lower positions through the connecting frame 52.

[0096] Movable components 13 are disposed on both sides of the drying cover 7 . The movable components 13 include two movable plates 131 . Movable through grooves 132 matched with the movable plates 131 are formed on the surface of the drying cover 7 .

[0097] A limiting device 10 is provided on the surface of the workbench 3 and above the conveyor belt 4. The limiting device 10 includes a double-headed hydraulic telescopic rod 101. Both ends of the double-headed hydraulic telescopic rod 101 are connected to movable rods 102 through connecting blocks. The opposite ends of the two movable rods 102 are connected to limiting plates 103. A fixing ring 104 is installed at the center position of the surface of the double-headed hydraulic telescopic rod 101. The fixing ring 104 is connected to the bottom of the workbench 3 through a connecting block.

[0098] When limiting the position of the alkali-acid pickling material frame 1 with the titanium alloy plate 2 moving on the surface of the conveyor belt 4, first start the double-headed hydraulic telescopic rod 101 to drive the limiting plate 103 to adjust through the movable rod 102. When the distance between the two limiting plates 103 is adjusted to a suitable distance, stop the operation of the double-headed hydraulic telescopic rod 101.

[0099] The working principle of the method for optimizing the alkali pickling surface of titanium plate provided by the present invention is as follows:

[0100] During use, after the alkali pickling material frame 1 with the titanium alloy plate 2 is placed on the surface of the conveyor belt 4 on one side of the workbench 3, the hydraulic telescopic rod 51 is started to drive the U-shaped fixing frame 61 with the wiping cotton 62 to contact the top of the alkali pickling material frame 1 through the connecting frame 52, and then the conveyor belt 4 is started to drive the alkali pickling material frame 1 with the titanium alloy plate 2 to move toward the inside of the drying cover 7. When the alkali pickling material frame 1 with the titanium alloy plate 2 moves, the liquid on the top of the alkali pickling material frame 1 is wiped by the wiping cotton 62 inside the U-shaped fixing frame 61. After the liquid on the top of the alkali pickling material frame 1 with the titanium alloy plate 2 is wiped and moved to the inside of the drying cover 7, the drying cover 7 is closed by pushing the movable plate 131 to move inside the movable through groove 132. Finally, the controller 9 is started to open the dryer 8, and the alkali pickling material frame 1 with the titanium alloy plate 2 can be dried.

[0101] Compared with the related art, the method for optimizing the alkali pickling surface of titanium plate provided by the present invention has the following beneficial effects:

[0102] The present invention provides a method for optimizing the alkali pickling surface of a titanium plate. A drying hood 7 with a dryer 8 and an adjusting device 5 and a wiping component 6 are arranged on a workbench 3 with multiple conveyor belts 4 to cooperate with each other. After an alkali pickling material frame 1 with a titanium alloy plate 2 is placed on the surface of the conveyor belt 4, the liquid on the top of the alkali pickling material frame 1 can be automatically wiped dry and then transported to the inside of the drying hood 7 for drying.

[0103] Third embodiment

[0104] Please refer to Figure 7 Based on the method for optimizing the alkali pickling surface of titanium plate provided by the first embodiment of the present application, the third embodiment of the present application proposes another method for optimizing the alkali pickling surface of titanium plate. The third embodiment is only a preferred method of the first embodiment, and the implementation of the third embodiment will not affect the independent implementation of the first embodiment.

[0105] Specifically, the difference of the method for optimizing the alkaline pickling surface of a titanium plate provided in the third embodiment of the present application is that, in a method for optimizing the alkaline pickling surface of a titanium plate, a disassembly component 11 is arranged between the connecting frame 52 and the U-shaped fixing frame 61, and the disassembly component 11 includes a disassembly sleeve 111, and a disassembly block 112 is arranged inside the disassembly sleeve 111, one end of the disassembly block 112 is connected to one end of the connecting frame 52, and a bolt 113 is arranged between the disassembly sleeve 111 and the disassembly block 112.

[0106] One end of the disassembly sleeve 111 is connected to the center position of the surface of the U-shaped fixing frame 61, and a threaded hole compatible with the bolt 113 is opened between the disassembly sleeve 111 and the disassembly block 112. The disassembly sleeve 111 and the disassembly block 112 are connected by plugging and unplugging.

[0107] The working principle of the method for optimizing the alkali pickling surface of titanium plate provided by the present invention is as follows:

[0108] During use, when the U-shaped fixing frame 61 with the wiping cotton 62 is disassembled and replaced, the bolt 113 between the disassembly sleeve 111 and the disassembly block 112 is first removed. After the bolt 113 is removed, the U-shaped fixing frame 61 with the wiping cotton 62 is pulled to drive the disassembly sleeve 111 to separate from the disassembly block 111 at one end of the connecting frame 52.

[0109] Compared with the related art, the method for optimizing the alkali pickling surface of titanium plate provided by the present invention has the following beneficial effects:

[0110] The present invention provides a method for optimizing the alkali pickling surface of a titanium plate. A disassembly sleeve 111, a disassembly block 112 and a bolt 113 are arranged between a connecting frame 52 and a U-shaped fixing frame 61 so that the U-shaped fixing frame 61 with a wiping cotton 62 can be regularly disassembled for replacement.

[0111] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for optimizing the alkaline pickling surface of titanium plate, characterized in that: The following steps are involved: S1. Frame loading: whiten the surface of the finished plate, load the titanium alloy plate into the alkali-acid washing frame, and load one titanium alloy plate into each grid of the alkali-acid washing frame, with the spacing between each grid not less than 100 mm; S2, alkali washing: after the titanium alloy plate inside the alkali pickling material frame in S1 is installed, the titanium alloy plate is immersed in an alkali melt at 470-490° C., wherein the alkali melt is composed of a mixture of 7-12% sodium nitrate and 88-93% sodium hydroxide by weight, and the alkali washing time is 1-30 minutes; S3, water washing: immersing the titanium alloy plate after alkali washing in S2 in a water tank at room temperature, and washing the alkali melt on the surface of the titanium alloy plate with water; S4, lifting and stringing: adjust the lifting frame of the titanium alloy plate washed with water in S3, and move the titanium alloy plate in the alkali-acid washing frame by about the position of a titanium rod, so as to avoid the color difference of the plate surface caused by the uneven corrosion rate of the contact part between the titanium alloy plate and the titanium rod in this process; S5, pickling: soaking the washed and stripped titanium alloy plate in an acidic solution containing 2-5% hydrofluoric acid and 20-40% nitric acid with the remainder being water, the pickling time being 1-3 minutes; S6. Washing with dilute sulfuric acid: Soak the pickled titanium alloy plate in a dilute sulfuric acid aqueous solution with a concentration of 20% and a temperature below 40°C for no more than 2 minutes. Rinse the titanium alloy plate that has passed through the dilute sulfuric acid tank with water to remove the acid marks remaining on the surface. Use a clean cloth to wipe off the alkali and acid on the top of the alkaline pickling frame to prevent alkali and acid dripping from contaminating the surface of the titanium alloy plate. Then dry it and remove the frame.

2. The method for optimizing the alkali pickling surface of titanium plate according to claim 1, characterized in that: The alkali pickling material frame in S1 can be divided into 1 to 3 rows of frames per grid according to the actual size of different plates. The pickled titanium rod is spot welded to change the contact mode between the titanium alloy plate and the titanium rod from line contact to point contact, which can reduce the generation of rod marks to a certain extent.

3. The method for optimizing the alkali pickling surface of titanium plate according to claim 1, characterized in that: In the S2, the medium and thick plates and titanium alloy plates such as TB5 and Ti230 which are easy to absorb hydrogen are not subjected to alkali washing.

4. The method for optimizing the alkali pickling surface of titanium plate according to claim 1, characterized in that: The titanium alloy plate 2 after pickling in S5 is pickled for the second time according to S5, which is suitable for the situation that the thickness of the titanium alloy plate does not meet the requirements. The titanium alloy plate after the second pickling according to S5 can also be pickled for the third time according to S5, which is suitable for the situation that the thickness of the titanium alloy plate still does not meet the requirements. Before each pickling, the material lifting and stringing step must be performed.

5. The method for optimizing the alkali pickling surface of titanium plate according to claim 1, characterized in that: In the step S6, the pickled titanium alloy plate is washed with dilute sulfuric acid to pre-neutralize the residual acid attached to the surface, so as to avoid acid reflux on the surface of the titanium alloy plate due to incomplete washing during direct water washing.

6. The method for optimizing the alkali pickling surface of titanium plate according to claim 1, characterized in that: In S6, a processing device is required for wiping the alkali-acid washing material frame and drying the titanium alloy plate. The processing device includes a workbench, three sets of conveyor belts are installed on the surface of the workbench, a drying hood is installed at the center of the workbench surface, an adjusting device is provided on one side of the top of the drying hood, a wiping assembly is provided at one end of the adjusting device, the wiping assembly includes a U-shaped fixing frame, wiping cotton is bonded to both sides and the top of the inner wall of the U-shaped fixing frame, dryers are installed on both sides and the top of the inner wall of the drying hood, and a controller is installed on the top of the drying hood.

7. The method for optimizing the alkali pickling surface of titanium plate according to claim 6, characterized in that: The adjusting device comprises a hydraulic telescopic rod, the top end of which is connected to a connecting frame, and one end of the connecting frame is connected to the center position of the surface of the U-shaped fixing frame.

8. The method for optimizing the alkali pickling surface of titanium plate according to claim 6, characterized in that: Both sides of the drying cover are provided with movable components, the movable components include two movable plates, and the surface of the drying cover is provided with movable through grooves adapted to the movable plates.

9. The method for optimizing the alkali pickling surface of titanium plate according to claim 6, characterized in that: A limiting device is arranged on the surface of the workbench and above the conveyor belt, and the limiting device includes a double-headed hydraulic telescopic rod, both ends of which are connected to movable rods via connecting blocks, and the opposite ends of the two movable rods are connected to limiting plates, and a fixing ring is installed at the center position of the surface of the double-headed hydraulic telescopic rod, and the fixing ring is connected to the bottom of the workbench via a connecting block.

10. The method for optimizing the alkali pickling surface of titanium plate according to claim 7, characterized in that: A disassembly assembly is arranged between the connecting frame and the U-shaped fixing frame, and the disassembly assembly includes a disassembly sleeve, a disassembly block is arranged inside the disassembly sleeve, one end of the disassembly block is connected to one end of the connecting frame, and a bolt is arranged between the disassembly sleeve and the disassembly block.

Images