Nickel-titanium oxide layer cleaning solution, preparation method thereof and application thereof

Abstract

This application relates to a nickel-titanium oxide layer cleaning solution, its preparation method, and its application. The cleaning solution comprises the following raw materials: HNO3 450-480 ml / L, H2SO4 150-180 ml / L, NaHF 24-6 g / L, NaNO2 0.6-1 g / L, C6H5N3 0.6-0.7 g / L, 1-hydroxymethylbenzotriazole 0-0.5 g / L, and the balance being deionized water. The cleaning solution is prepared by accurately weighing each raw material according to the specified ratio, stirring and mixing them thoroughly to obtain the nickel-titanium oxide layer cleaning solution. The cleaning solution can be used to clean the oxide layer on the surface of nickel-titanium alloy materials. The cleaning solution in this application can quickly and uniformly remove the oxide layer on the surface of nickel-titanium materials, while simultaneously inhibiting hydrogen ion penetration into the substrate to prevent hydrogen embrittlement, greatly reducing the corrosion of the substrate by the cleaning solution and lowering the risk of corrosion.

Description

Technical Field

[0001] This application relates to the field of cleaning solutions, and in particular to a nickel-titanium oxide layer cleaning solution, its preparation method, and its application. Background Technology

[0002] Nickel-titanium alloys possess excellent strain resistance and good biocompatibility, making them ideal materials for medical device design. For example, nickel-titanium materials are used to create nickel-titanium stents for treating stenosis and occlusion of cardiovascular and cerebrovascular vessels. However, after implantation, if the surface of the nickel-titanium stent is not smooth enough, biological reactions can easily occur, leading to blood clotting and vascularization around the stent, potentially resulting in new thrombi. Therefore, to ensure a sufficiently smooth surface, nickel-titanium stents require electrochemical polishing before molding. To ensure the quality of this electrochemical polishing, the oxide layer formed on the surface after cutting the stent needs to be removed.

[0003] During laser cutting of nickel-titanium alloys, the high temperature and speed cause the cut edges to absorb oxygen, forming an oxide layer. This oxide layer, formed in a high-temperature air environment, exists in multiple layers, making it more firmly attached to the nickel-titanium alloy surface. Effective removal requires a high-strength cleaning agent. Currently, acidic cleaning solutions are commonly used to clean nickel-titanium supports to remove the oxide layer. However, during the cleaning process, strong acid oxidation can easily lead to severe corrosion of the substrate. Furthermore, hydrogen released during the oxidation-reduction process can easily penetrate into the substrate, causing hydrogen embrittlement and resulting in product breakage and failure.

[0004] In order to control hydrogen embrittlement and reduce substrate corrosion, this application provides a nickel-titanium oxide cleaning solution, its preparation method, and its application. Summary of the Invention

[0005] In order to control hydrogen embrittlement during the cleaning of nickel-titanium materials and reduce substrate corrosion, this application provides a nickel-titanium oxide layer cleaning solution, its preparation method, and its application.

[0006] In a first aspect, this application provides a nickel-titanium oxide layer cleaning solution, which adopts the following technical solution: A nickel-titanium oxide layer cleaning solution comprises the following raw materials: HNO3 450-480 ml / L, H2SO4 150-180 ml / L, NaHF 24-6 g / L, NaNO2 0.6-1 g / L, C6H5N3 0.6-0.7 g / L, 1-hydroxymethylbenzotriazole 0-0.5 g / L, hexamethylenetetramine 0-0.3 g / L, and the balance being deionized water.

[0007] By adopting the above technical solution, the oxide layer generated on the surface of the nickel-titanium substrate when it is cut to form a support mainly consists of nickel monoxide and titanium dioxide. Nickel monoxide can react with sulfuric acid to form nickel sulfate, and titanium dioxide can react with sulfuric acid to form titanium sulfate. Sodium hydrofluoric acid can decompose into sodium fluoride and hydrogen fluoride in water, and fluoride ions can form stable complexes with nickel and titanium ions. During the pickling process, benzotriazole can interact with nickel and titanium to form a precipitate protective film on the substrate surface, thereby playing a corrosion inhibition role and reducing the possibility of excessive corrosion of the substrate. Sodium nitrite can form an insoluble oxide film on the substrate surface, and the insoluble oxide film covering the metal surface plays a corrosion inhibition and protection role.

[0008] When removing the oxide layer on the surface of nickel-titanium materials using strong oxidizing acids, it is crucial to minimize the generation of hydrogen to avoid damaging the internal structure of the nickel-titanium material. Nickel-titanium is a superelastic material, and its interior is highly sensitive to hydrogen ions; even small amounts or trace amounts can easily lead to brittle fracture. This application selects nitric acid as the primary oxidant. The nitric acid reacts with the oxides in the oxide layer, dissolving it and preferentially removing most of the oxide layer from the nickel-titanium material surface. Sulfuric acid and sodium hydrofluoric acid, which are relatively less corrosive, are then used to further remove the oxide layer. Additionally, the oxide layer contains a small amount of elemental nickel-titanium and contains micropores and fine cracks. The cleaning solution can react with the elemental nickel-titanium in the oxide layer and the substrate through these micropores and cracks, generating hydrogen gas. The expansion pressure of the hydrogen gas causes the oxide layer to peel off from the substrate surface. Then, the corrosion-inhibiting effects of sodium nitrite and benzotriazole are used to form a protective film on the substrate surface to prevent hydrogen ions from penetrating into the substrate. This achieves oxide layer removal while simultaneously reducing hydrogen embrittlement and corrosion of the substrate.

[0009] In one specific feasible implementation, the following raw materials are included: HNO3 460 ml / L, H2SO4 174 ml / L, NaHF 25 g / L, NaNO2 1 g / L, C6H5N3 0.6 g / L, with the balance being deionized water.

[0010] In one specific feasible implementation, the following raw materials are included: HNO3 450-480 ml / L, H2SO4 150-180 ml / L, NaHF 24-6 g / L, NaNO2 0.6-1 g / L, C6H5N3 0.6-0.7 g / L, 1-hydroxymethylbenzotriazole 0.3-0.5 g / L, and the balance being deionized water.

[0011] By adopting the above technical solution, 1-hydroxymethylbenzotriazole, compared with C6H5N3, has a hydroxymethyl group attached to the benzene ring, making it more reactive than C6H5N3. During use, the cleaning solution is generally heated to improve the cleaning effect and speed. While increasing the temperature accelerates the cleaning process, it also increases the corrosion rate of the acid on the nickel-titanium substrate. When the operating temperature rises, the more reactive 1-hydroxymethylbenzotriazole plays a major role in corrosion inhibition, ensuring that a protective film can form on the substrate surface in a timely manner, thereby reducing the possibility of hydrogen ions penetrating into the substrate and causing corrosion.

[0012] In one specific implementation scheme, the mass ratio of C6H5N3 to 1-hydroxymethylbenzotriazole is (1.2-1.5):1.

[0013] In one specific implementation scheme, the mass ratio of C6H5N3 to 1-hydroxymethylbenzotriazole is 1.5:1.

[0014] By adopting the above technical solution, C6H5N3 and 1-hydroxymethylbenzotriazole are compounded in a specific ratio. When the operating temperature is relatively low, the C6H5N3 with a higher proportion plays the main role in corrosion inhibition. When the temperature rises, the more active 1-hydroxymethylbenzotriazole participates in the protection of the substrate and plays the main protective role, thereby achieving the protection of the substrate surface and reducing the possibility of the substrate being severely corroded.

[0015] In one specific feasible implementation, the following raw materials are included: HNO3 450-480 ml / L, H2SO4 150-180 ml / L, NaHF 24-6 g / L, NaNO2 0.6-1 g / L, C6H5N3 0.6-0.7 g / L, 1-hydroxymethylbenzotriazole 0.3-0.5 g / L, hexamethylenetetramine 0.1-0.3 g / L, and the balance being deionized water.

[0016] By employing the above technical solution, hexamethylenetetramine can adsorb onto the substrate surface to form a protective film, thereby reducing the corrosion of the substrate by the cleaning solution and preventing hydrogen ions from penetrating into the substrate. When the temperature rises, hexamethylenetetramine can synergistically work with benzotriazole and 1-hydroxymethylbenzotriazole to rapidly form a protective film on the substrate surface, thus reducing the possibility that the increased activity of the cleaning solution at higher temperatures will accelerate substrate corrosion.

[0017] In one specific feasible implementation, the following raw materials are included: HNO3 460 ml / L, H2SO4 174 ml / L, NaHF 25 g / L, NaNO2 1 g / L, C6H5N3 0.6 g / L, 1-hydroxymethylbenzotriazole 0.5 g / L, hexamethylenetetramine 0.2 g / L, and the balance being deionized water.

[0018] By adopting the above technical solution and optimizing the raw material ratio, the cleaning solution can effectively remove the oxide layer on the surface of nickel-titanium alloy at 60℃. After cleaning with the cleaning solution, the surface of nickel-titanium alloy is smooth and flat, and the surface roughness value can reach 1.21μm. At the same time, the nickel-titanium alloy is subjected to minimal corrosion and no hydrogen embrittlement fracture occurs.

[0019] Secondly, this application provides a method for preparing a nickel-titanium oxide layer cleaning solution, which adopts the following technical solution: a method for preparing a nickel-titanium oxide layer cleaning solution, wherein each raw material is accurately weighed according to the ratio, and the raw materials are stirred and mixed to obtain a nickel-titanium oxide layer cleaning solution.

[0020] Thirdly, this application provides a method for applying a nickel-titanium oxide layer cleaning solution, employing the following technical solution: An application of a nickel-titanium oxide layer cleaning solution for removing oxide layers from the surface of nickel-titanium alloy materials.

[0021] In one specific feasible implementation, when using a nickel-titanium oxide cleaning solution to clean nickel-titanium alloy materials, the temperature is controlled at 55-60℃.

[0022] By employing the above technical solution, when the temperature is too low, the cleaning solution removes the oxide layer slowly and incompletely. When the temperature is too high, the activity of the acid in the cleaning solution increases. Although this can speed up the cleaning process, the nickel-titanium substrate, which is sensitive to hydrogen ions, becomes more easily penetrated by hydrogen ions, and the degree of corrosion is more significantly aggravated. In addition, nitric acid will also decompose at excessively high temperatures, causing the cleaning solution to lose its cleaning effectiveness. By controlling the appropriate temperature, not only can the oxide layer on the surface of the nickel-titanium material be fully removed, but the possibility of corrosion of the nickel-titanium substrate can also be reduced.

[0023] In summary, this application includes at least one of the following beneficial technical effects: 1. This application uses HNO3, H2SO4, NaHF2, NaNO2, C6H5N3 and water in a specific ratio to prepare a cleaning solution, which can not only fully remove the oxide layer on the surface of nickel-titanium substrate, but also effectively inhibit hydrogen ions from penetrating into the substrate and causing hydrogen embrittlement, thus effectively reducing the possibility of substrate corrosion. 2. This application uses a combination of 1-hydroxymethylbenzotriazole and C6H5N3, which enables the cleaning solution to effectively remove the oxide layer on the nickel-titanium surface even when the operating temperature of the cleaning solution changes, while also effectively reducing the possibility of substrate corrosion. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the oxide layer on the surface of the sample after laser cutting; Figure 2This is a surface view of the sample after polishing when the oxide layer on the sample surface has not been removed; Figure 3 This is a surface view of the sample after the oxide layer was removed and then polished. Figure 4 This is a surface view of the sample in Example 1 after cleaning with the cleaning solution; Figure 5 This is a surface view of the sample in Example 1 after it has been cleaned and then polished. Figure 6 This is a surface view of the sample in Comparative Example 6 after cleaning with the cleaning solution. Figure 7 This is a surface view of the sample in Comparative Example 7 after cleaning with the cleaning solution; Figure 8 This is a surface view of the sample in Comparative Example 8 after cleaning with the cleaning solution; Figure 9 This is a surface view of the sample in Comparative Example 9 after cleaning with the cleaning solution; Figure 10 This is a surface view of the sample in Comparative Example 10 after cleaning with the cleaning solution; Figure 11 The image shows the hydrogen embrittlement fracture phenomenon that occurred after the sample in Comparative Example 11 was bent following cleaning with the cleaning solution. Figure 12 This is a surface view of the sample in Comparative Example 12 after cleaning with the cleaning solution; Figure 13 This is a surface view of the sample in Comparative Example 14 after cleaning with the cleaning solution. Figure 14 This is a surface view of the sample in Comparative Example 15 after cleaning with the cleaning solution; Figure 15 This is a surface view of the sample in Comparative Example 16 after cleaning with the cleaning solution. Figure 16 This is a diagram showing the corrosion on the surface of the sample in Comparative Example 17 after cleaning with the cleaning solution. Figure 17 The image shows the oxide layer on the surface of the sample in Comparative Example 17 after cleaning with the cleaning solution. Figure 18 The image shows the hydrogen embrittlement fracture of the sample in Comparative Example 17 after cleaning with the cleaning solution. Figure 19 This is a surface view of the sample in Comparative Example 18 after cleaning with the cleaning solution; Figure 20 This is a surface view of the sample in Comparative Example 19 after cleaning with the cleaning solution. Detailed Implementation

[0025] The following is in conjunction with the appendix Figure 1-20 The present application will be further described in detail with reference to the embodiments.

[0026] All raw materials used in this application are commercially available. Example

[0027] Example 1 A nickel-titanium oxide cleaning solution comprises the following raw materials: HNO3 450 ml / L, H2SO4 150 ml / L, NaHF 24 g / L, NaNO2 0.6 g / L, C6H5N 30.7 g / L, with the balance being deionized water.

[0028] During preparation, each raw material is accurately weighed, stirred and mixed to obtain a nickel-titanium oxide layer cleaning solution.

[0029] When using the nickel-titanium oxide cleaning solution to remove the oxide layer on the surface of nickel-titanium alloy materials, the temperature of the cleaning solution should be controlled at 55℃.

[0030] Example 2 A nickel-titanium oxide cleaning solution comprises the following raw materials: HNO3 460 ml / L, H2SO4 174 ml / L, NaHF 25 g / L, NaNO2 1 g / L, C6H5N 30.6 g / L, with the balance being deionized water.

[0031] During preparation, each raw material is accurately weighed, stirred and mixed to obtain a nickel-titanium oxide layer cleaning solution.

[0032] When using the nickel-titanium oxide cleaning solution to remove the oxide layer on the surface of nickel-titanium alloy materials, the temperature of the cleaning solution should be controlled at 55℃.

[0033] Example 3 A nickel-titanium oxide cleaning solution comprises the following raw materials: HNO3 480 ml / L, H2SO4 180 ml / L, NaHF 26 g / L, NaNO2 0.8 g / L, C6H5N 30.7 g / L, with the balance being deionized water.

[0034] During preparation, each raw material is accurately weighed, stirred and mixed to obtain a nickel-titanium oxide layer cleaning solution.

[0035] When using the nickel-titanium oxide cleaning solution to remove the oxide layer on the surface of nickel-titanium alloy materials, the temperature of the cleaning solution should be controlled at 55℃.

[0036] Example 4 A nickel-titanium oxide cleaning solution comprises the following raw materials: HNO3 460 ml / L, H2SO4 174 ml / L, NaHF 25 g / L, NaNO2 1 g / L, C6H5N 30.6 g / L, with the balance being deionized water.

[0037] During preparation, each raw material is accurately weighed, stirred and mixed to obtain a nickel-titanium oxide layer cleaning solution.

[0038] When using the nickel-titanium oxide cleaning solution to remove the oxide layer on the surface of nickel-titanium alloy materials, the temperature of the cleaning solution should be controlled at 58℃.

[0039] Example 5 A nickel-titanium oxide cleaning solution comprises the following raw materials: HNO3 460 ml / L, H2SO4 174 ml / L, NaHF 25 g / L, NaNO2 1 g / L, C6H5N 30.6 g / L, with the balance being deionized water.

[0040] During preparation, each raw material is accurately weighed, stirred and mixed to obtain a nickel-titanium oxide layer cleaning solution.

[0041] When using the nickel-titanium oxide cleaning solution to remove the oxide layer on the surface of nickel-titanium alloy materials, the temperature of the cleaning solution should be controlled at 60℃.

[0042] Example 6 A nickel-titanium oxide cleaning solution comprises the following raw materials: HNO3 460 ml / L, H2SO4 174 ml / L, NaHF 25 g / L, NaNO2 1 g / L, C6H5N3 0.6 g / L, 1-hydroxymethylbenzotriazole 0.5 g / L, and the balance being deionized water.

[0043] During preparation, each raw material is accurately weighed, stirred and mixed to obtain a nickel-titanium oxide layer cleaning solution.

[0044] When using the nickel-titanium oxide cleaning solution to remove the oxide layer on the surface of nickel-titanium alloy materials, the temperature of the cleaning solution should be controlled at 55℃.

[0045] Example 7 A nickel-titanium oxide cleaning solution comprises the following raw materials: HNO3 460 ml / L, H2SO4 174 ml / L, NaHF 25 g / L, NaNO2 1 g / L, C6H5N3 0.7 g / L, 1-hydroxymethylbenzotriazole 0.4 g / L, and the balance being deionized water.

[0046] During preparation, each raw material is accurately weighed, stirred and mixed to obtain a nickel-titanium oxide layer cleaning solution.

[0047] When using the nickel-titanium oxide cleaning solution to remove the oxide layer on the surface of nickel-titanium alloy materials, the temperature of the cleaning solution should be controlled at 55℃.

[0048] Example 8 A nickel-titanium oxide cleaning solution comprises the following raw materials: HNO3 460 ml / L, H2SO4 174 ml / L, NaHF 25 g / L, NaNO2 1 g / L, C6H5N3 0.7 g / L, 1-hydroxymethylbenzotriazole 0.3 g / L, and the balance being deionized water.

[0049] During preparation, each raw material is accurately weighed, stirred and mixed to obtain a nickel-titanium oxide layer cleaning solution.

[0050] When using the nickel-titanium oxide cleaning solution to remove the oxide layer on the surface of nickel-titanium alloy materials, the temperature of the cleaning solution should be controlled at 55℃.

[0051] Example 9 A nickel-titanium oxide cleaning solution comprises the following raw materials: HNO3 460 ml / L, H2SO4 174 ml / L, NaHF 25 g / L, NaNO2 1 g / L, C6H5N3 0.6 g / L, 1-hydroxymethylbenzotriazole 0.4 g / L, and the balance being deionized water.

[0052] During preparation, each raw material is accurately weighed, stirred and mixed to obtain a nickel-titanium oxide layer cleaning solution.

[0053] When using the nickel-titanium oxide cleaning solution to remove the oxide layer on the surface of nickel-titanium alloy materials, the temperature of the cleaning solution should be controlled at 55℃.

[0054] Example 10 A nickel-titanium oxide cleaning solution comprises the following raw materials: HNO3 460 ml / L, H2SO4 174 ml / L, NaHF 25 g / L, NaNO2 1 g / L, C6H5N3 0.69 g / L, 1-hydroxymethylbenzotriazole 0.41 g / L, and the balance being deionized water.

[0055] During preparation, each raw material is accurately weighed, stirred and mixed to obtain a nickel-titanium oxide layer cleaning solution.

[0056] When using the nickel-titanium oxide cleaning solution to remove the oxide layer on the surface of nickel-titanium alloy materials, the temperature of the cleaning solution should be controlled at 55℃.

[0057] Example 11 A nickel-titanium oxide cleaning solution comprises the following raw materials: HNO3 460 ml / L, H2SO4 174 ml / L, NaHF 25 g / L, NaNO2 1 g / L, C6H5N3 0.7 g / L, 1-hydroxymethylbenzotriazole 0.4 g / L, and the balance being deionized water.

[0058] During preparation, each raw material is accurately weighed, stirred and mixed to obtain a nickel-titanium oxide layer cleaning solution.

[0059] When using the nickel-titanium oxide cleaning solution to remove the oxide layer on the surface of nickel-titanium alloy materials, the temperature of the cleaning solution should be controlled at 58℃.

[0060] Example 12 A nickel-titanium oxide cleaning solution comprises the following raw materials: HNO3 460 ml / L, H2SO4 174 ml / L, NaHF 25 g / L, NaNO2 1 g / L, C6H5N3 0.7 g / L, 1-hydroxymethylbenzotriazole 0.4 g / L, and the balance being deionized water.

[0061] During preparation, each raw material is accurately weighed, stirred and mixed to obtain a nickel-titanium oxide layer cleaning solution.

[0062] When using the nickel-titanium oxide cleaning solution to remove the oxide layer on the surface of nickel-titanium alloy materials, the temperature of the cleaning solution should be controlled at 60℃.

[0063] Example 13 An application of the nickel-titanium oxide cleaning solution prepared in Example 1 is used to remove the oxide layer on the surface of nickel-titanium alloy materials.

[0064] Comparative Example Comparative Example 1 A nickel-titanium oxide cleaning solution comprises the following raw materials: 600 ml / L H2SO4, 24 g / L NaHF, 0.6 g / L NaNO2, 0.7 g / L C6H5N3, with the balance being deionized water.

[0065] During preparation, each raw material is accurately weighed, stirred and mixed to obtain a nickel-titanium oxide layer cleaning solution.

[0066] Comparative Example 2 A nickel-titanium oxide cleaning solution comprises the following raw materials: 600 ml / L HNO3, 24 g / L NaHF, 0.6 g / L NaNO2, 0.7 g / L C6H5N3, with the balance being deionized water.

[0067] During preparation, each raw material is accurately weighed, stirred and mixed to obtain a nickel-titanium oxide layer cleaning solution.

[0068] Comparative Example 3 A nickel-titanium oxide cleaning solution comprises the following raw materials: HF 450 ml / L, H2SO4 150 ml / L, NaHF 24 g / L, NaNO2 0.6 g / L, C6H5N 30.7 g / L, with the balance being deionized water.

[0069] During preparation, each raw material is accurately weighed, stirred and mixed to obtain a nickel-titanium oxide layer cleaning solution.

[0070] Comparative Example 4 A nickel-titanium oxide cleaning solution comprises the following raw materials: HCl 450ml / L, H2SO4 150ml / L, NaHF 24g / L, NaNO2 0.6g / L, C6H5N 30.7g / L, with the balance being deionized water.

[0071] During preparation, each raw material is accurately weighed, stirred and mixed to obtain a nickel-titanium oxide layer cleaning solution.

[0072] Comparative Example 5 A nickel-titanium oxide cleaning solution comprises the following raw materials: oxalic acid 450 ml / L, H2SO4 150 ml / L, NaHF 24 g / L, NaNO2 0.6 g / L, C6H5N 30.7 g / L, with the balance being deionized water.

[0073] During preparation, each raw material is accurately weighed, stirred and mixed to obtain a nickel-titanium oxide layer cleaning solution.

[0074] Comparative Example 6 A nickel-titanium oxide cleaning solution comprises the following raw materials: 200 ml / L HNO3, 150 ml / L H2SO4, 24 g / L NaHF, 0.6 g / L NaNO2, 0.7 g / L C6H5N3, with the balance being deionized water.

[0075] During preparation, each raw material is accurately weighed, stirred and mixed to obtain a nickel-titanium oxide layer cleaning solution.

[0076] Comparative Example 7 A nickel-titanium oxide cleaning solution comprises the following raw materials: HNO3 350 ml / L, H2SO4 150 ml / L, NaHF 24 g / L, NaNO2 0.6 g / L, C6H5N 30.7 g / L, with the balance being deionized water.

[0077] During preparation, each raw material is accurately weighed, stirred and mixed to obtain a nickel-titanium oxide layer cleaning solution.

[0078] Comparative Example 8 A nickel-titanium oxide cleaning solution comprises the following raw materials: HNO3 550 ml / L, H2SO4 150 ml / L, NaHF 24 g / L, NaNO2 0.6 g / L, C6H5N 30.7 g / L, with the balance being deionized water.

[0079] Comparative Example 9 A nickel-titanium oxide cleaning solution comprises the following raw materials: HNO3 700 ml / L, H2SO4 150 ml / L, NaHF 24 g / L, NaNO2 0.6 g / L, C6H5N 30.7 g / L, with the balance being deionized water.

[0080] During preparation, each raw material is accurately weighed, stirred and mixed to obtain a nickel-titanium oxide layer cleaning solution.

[0081] Comparative Example 10 A nickel-titanium oxide cleaning solution comprises the following raw materials: HNO3 450 ml / L, H2SO4 120 ml / L, NaHF 24 g / L, NaNO2 0.6 g / L, C6H5N 30.7 g / L, with the balance being deionized water.

[0082] During preparation, each raw material is accurately weighed, stirred and mixed to obtain a nickel-titanium oxide layer cleaning solution.

[0083] Comparative Example 11 A nickel-titanium oxide cleaning solution comprises the following raw materials: HNO3 450 ml / L, H2SO4 200 ml / L, NaHF 24 g / L, NaNO2 0.6 g / L, C6H5N 30.7 g / L, with the balance being deionized water.

[0084] During preparation, each raw material is accurately weighed, stirred and mixed to obtain a nickel-titanium oxide layer cleaning solution.

[0085] Comparative Example 12 A nickel-titanium oxide cleaning solution comprises the following raw materials: HNO3 450 ml / L, H2SO4 150 ml / L, NaHF 22 g / L, NaNO2 0.6 g / L, C6H5N 30.7 g / L, with the balance being deionized water.

[0086] During preparation, each raw material is accurately weighed, stirred and mixed to obtain a nickel-titanium oxide layer cleaning solution.

[0087] Comparative Example 13 A nickel-titanium oxide cleaning solution comprises the following raw materials: HNO3 450 ml / L, H2SO4 150 ml / L, NaHF 28 g / L, NaNO2 0.6 g / L, C6H5N 30.7 g / L, with the balance being deionized water.

[0088] During preparation, each raw material is accurately weighed, stirred and mixed to obtain a nickel-titanium oxide layer cleaning solution.

[0089] Comparative Example 14 A nickel-titanium oxide cleaning solution comprises the following raw materials: HNO3 460 ml / L, H2SO4 174 ml / L, NaHF 25 g / L, NaNO2 1 g / L, C6H5N 30.6 g / L, with the balance being deionized water.

[0090] During preparation, each raw material is accurately weighed, stirred and mixed to obtain a nickel-titanium oxide layer cleaning solution.

[0091] When using the nickel-titanium oxide cleaning solution to remove the oxide layer on the surface of nickel-titanium alloy materials, the temperature of the cleaning solution should be controlled at 25℃.

[0092] Comparative Example 15 A nickel-titanium oxide cleaning solution comprises the following raw materials: HNO3 460 ml / L, H2SO4 174 ml / L, NaHF 25 g / L, NaNO2 1 g / L, C6H5N 30.6 g / L, with the balance being deionized water.

[0093] During preparation, each raw material is accurately weighed, stirred and mixed to obtain a nickel-titanium oxide layer cleaning solution.

[0094] When using the nickel-titanium oxide cleaning solution to remove the oxide layer on the surface of nickel-titanium alloy materials, the temperature of the cleaning solution should be controlled at 50℃.

[0095] Comparative Example 16 A nickel-titanium oxide cleaning solution comprises the following raw materials: HNO3 460 ml / L, H2SO4 174 ml / L, NaHF 25 g / L, NaNO2 1 g / L, C6H5N 30.6 g / L, with the balance being deionized water.

[0096] During preparation, each raw material is accurately weighed, stirred and mixed to obtain a nickel-titanium oxide layer cleaning solution.

[0097] When using the nickel-titanium oxide cleaning solution to remove the oxide layer on the surface of nickel-titanium alloy materials, the temperature of the cleaning solution should be controlled at 70℃.

[0098] Comparative Example 17 A nickel-titanium oxide cleaning solution comprises the following raw materials: HF 300ml / L, HNO3 200ml / L, HCl 150ml / L, C6H5N 32g / L, with the balance being deionized water.

[0099] During preparation, each raw material is accurately weighed, stirred and mixed to obtain a nickel-titanium oxide layer cleaning solution.

[0100] When using the nickel-titanium oxide cleaning solution to remove the oxide layer on the surface of nickel-titanium alloy materials, the temperature of the cleaning solution should be controlled at 55℃.

[0101] Comparative Example 18 A nickel-titanium oxide layer cleaning solution comprises the following raw materials: concentrated nitric acid and concentrated hydrochloric acid in a volume ratio of 1:3, wherein the mass fraction of concentrated nitric acid is 65% and the mass fraction of concentrated hydrochloric acid is 35%.

[0102] During preparation, each raw material is accurately weighed, stirred and mixed to obtain a nickel-titanium oxide layer cleaning solution.

[0103] When using the nickel-titanium oxide cleaning solution to remove the oxide layer on the surface of nickel-titanium alloy materials, the temperature of the cleaning solution should be controlled at 55℃.

[0104] Comparative Example 19 A nickel-titanium oxide cleaning solution comprises the following raw materials: 550 ml / L H2SO4, 250 ml / L HCl, and the balance being deionized water.

[0105] During preparation, each raw material is accurately weighed, stirred and mixed to obtain a nickel-titanium oxide layer cleaning solution.

[0106] When using the nickel-titanium oxide cleaning solution to remove the oxide layer on the surface of nickel-titanium alloy materials, the temperature of the cleaning solution should be controlled at 55℃.

[0107] Performance testing A nickel-titanium alloy sample measuring 13 cm in length and 0.52 cm in width, prepared by laser cutting, was used. The oxide layer formed at the cut edge after laser cutting was as follows: Figure 1 As shown, electrochemical polishing is performed without removing the oxide layer, resulting in a rough and serrated surface on the polished material. Figure 2 After the oxide layer is removed, electrochemical polishing is performed, resulting in a smooth and delicate material surface, such as... Figure 3 The nickel-titanium alloy material samples with oxide layers were ultrasonically cleaned for 1 minute using the cleaning solutions in each example and each comparative example, and then electrochemically polished. The sample surface was observed under a microscope and the surface roughness was measured using a roughness meter after cleaning and polishing.

[0108] Table 1 Performance Test Results Referring to Table 1, compared with Comparative Examples 1 to 5 and Comparative Examples 17 to 19, the nickel-titanium oxide cleaning solutions in Examples 1 to 3 can effectively remove the oxide layer on the surface of nickel and titanium without causing corrosion or hydrogen embrittlement. This indicates that the cleaning solution disclosed in this application can effectively control the substrate from being corroded while removing the oxide layer, and can reduce the possibility of hydrogen ions penetrating into the substrate and causing hydrogen embrittlement.

[0109] In conjunction with Examples 2, 4, 5, and Comparative Examples 14 to 16, exceeding the temperature range defined in this application resulted in incomplete removal of the oxide layer on the substrate surface or corrosion, which also affected the subsequent polishing effect. Analysis suggests that at excessively low temperatures, the activity of the active ingredients in the cleaning solution is low, failing to effectively dissolve and peel off the oxide layer from the substrate surface. At excessively high temperatures, although the increased activity of the cleaning solution can better dissolve and peel off the oxide layer, the degree of corrosion to the substrate also increases. Therefore, by limiting a suitable temperature range, the cleaning solution can achieve excellent removal of the oxide layer on the surface of nickel-titanium alloy materials.

[0110] In conjunction with Examples 2, 6 to 10, by adding 1-hydroxymethylbenzotriazole to combine it with C6H5N3, C6H5N3 plays the main role in corrosion inhibition at lower temperatures, while the more active 1-hydroxymethylbenzotriazole plays the main role in corrosion inhibition at higher temperatures. This allows a protective film to be formed on the substrate surface, reducing the possibility of the substrate being corroded or penetrated by hydrogen ions.

[0111] In conjunction with Examples 1, 6 to 9, the oxide layer on the surface of the samples in Examples 6 to 9 was not well removed, and even passivation occurred. The subsequent polishing effect was also relatively poor. This indicates that if the HNO3 content is too low, it cannot achieve the expected cleaning effect, and if the content is too high, it will cause corrosion or passivation. Only within the range defined in this application can the cleaning solution have an excellent cleaning effect on the samples.

[0112] As can be seen from Examples 1, 10 and 11, the content of H2SO4 affects the cleaning effect of the cleaning solution on the sample. By preparing the cleaning solution within the range defined in this application, the expected cleaning effect of the sample can be achieved better, while also reducing the possibility of corrosion of the substrate or hydrogen embrittlement.

[0113] In conjunction with Examples 1, 12, and 13, both excessively high and low NaHF2 content can affect the cleaning effect of the cleaning solution on the sample. Adding NaHF2 within the scope disclosed in this application can not only enable the cleaning solution to effectively remove the oxide layer on the sample surface and ensure the subsequent polishing effect, but also reduce the possibility of substrate corrosion.

[0114] To verify the wide applicability of the cleaning solution in this application, a nickel-titanium alloy sample that has not been laser-cut was taken. The sample had an oxide layer on its surface. The cleaning solution in Example 1 was used to clean the sample. After cleaning, it was observed that the oxide layer on the sample surface was completely removed, and the surface roughness value was 1.52 μm. This indicates that the cleaning solution in this application can effectively remove the oxide layer on the surface of nickel-titanium alloy, including the strong oxide layer generated at the cut edge during laser cutting and the oxide layer not generated by laser cutting.

[0115] The above are all preferred embodiments of this application and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made to the formula, principle and preparation method of this application should be covered within the scope of protection of this application.

Claims

1. An application of a nickel-titanium oxide layer cleaning solution, characterized in that: The nickel-titanium oxide cleaning solution consists of the following raw materials: HNO3 450-480 ml / L, H2SO4 150-180 ml / L, NaHF 24-6 g / L, NaNO2 0.6-1 g / L, C6H5N3 0.6-0.7 g / L, 1-hydroxymethylbenzotriazole 0.3-0.5 g / L, with the balance being deionized water; The preparation method of the nickel-titanium oxide layer cleaning solution is as follows: according to the ratio, accurately weigh each raw material, stir and mix each raw material to obtain the nickel-titanium oxide layer cleaning solution; The nickel-titanium oxide layer cleaning solution is used to clean nickel-titanium alloy materials and remove the oxide layer on the surface of the nickel-titanium alloy materials; the cleaning temperature is controlled at 58-60℃. The mass ratio of C6H5N3 to 1-hydroxymethylbenzotriazole is (1.2-1.5):

1.

2. The application of the nickel-titanium oxide layer cleaning solution according to claim 1, characterized in that: The mass ratio of C6H5N3 to 1-hydroxymethylbenzotriazole is 1.5:

1.

3. The application of the nickel-titanium oxide layer cleaning solution according to claim 1, characterized in that: The cleaning temperature is controlled at 60℃.

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