A high-hydrophilic nickel-silver alloy, a preparation method and application thereof

Abstract

The application provides a high-hydrophilic nickel-silver alloy and a preparation method and application thereof, a nickel metal is used as a base body, and metal silver is deposited on the surface of the base body as a plating layer, the water contact angle of the alloy surface is less than 90 DEG, the nickel-silver alloy obtained by a traditional preparation method cannot obtain good hydrophilicity, and thus the use of the nickel-silver alloy in many fields is limited, and the nickel-silver alloy has the defects of being limited in use. Through the process of heat treatment after silver plating on the surface of the nickel base body, the prepared nickel-silver alloy has high hydrophilicity, and through regulation and control of the treatment process, super-hydrophilicity can even be realized, so that the nickel-silver alloy can play a greater role in the field of surface heat transfer, and has important significance.

Description

Technical Field

[0001] This invention belongs to the field of hydrophilic alloy preparation technology, specifically relating to a highly hydrophilic nickel-silver alloy, its preparation method, and its application. Background Technology

[0002] Nickel-silver alloy is a high-quality alloy material composed of silver and nickel, possessing excellent corrosion resistance, heat resistance, and good electrical conductivity. It is widely used in industries such as electronics, metallurgy, and chemicals, and is an important material for many high-end products. Nickel-silver alloy also exhibits excellent weldability and machinability, allowing it to adapt to various process requirements.

[0003] Hydrophilic alloy surfaces exhibit many superior properties, particularly in improving surface heat exchange efficiency. In recent years, numerous studies have also demonstrated the significant role of hydrophilic surfaces in promoting heat transfer, leading to their widespread application in various heat transfer fields.

[0004] For nickel-silver alloys, a hydrophilic surface can reduce the formation of bubbles and water films on the material surface. During heat transfer, bubbles and water films can affect heat transfer and reduce heat transfer efficiency. By making the surface of nickel-silver alloys hydrophilic, the formation of bubbles and water films can be reduced, and heat transfer efficiency can be improved, which is of great significance for its application.

[0005] Currently, there are no literature reports or patented technologies for improving the hydrophilicity of nickel-silver alloy surfaces. Therefore, there is a need to develop a simple and easy-to-implement method to improve the hydrophilicity of nickel-silver alloy surfaces. Summary of the Invention

[0006] The purpose of this section is to outline some aspects of embodiments of the present invention and to briefly describe some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of this application, to avoid obscuring the purpose of these documents; however, such simplifications or omissions should not be construed as limiting the scope of the invention.

[0007] In view of the problems existing in the above and / or prior art, the present invention is proposed.

[0008] Therefore, the purpose of this invention is to overcome the shortcomings of the prior art and provide a highly hydrophilic nickel-silver alloy, wherein the alloy uses nickel metal as a substrate, and metallic silver is deposited on the surface of the substrate as a coating, and the water contact angle of the alloy surface is <90°.

[0009] Another object of the present invention is to provide a method for preparing a highly hydrophilic nickel-silver alloy.

[0010] To solve the above-mentioned technical problems, the present invention provides the following technical solution: including,

[0011] Remove oil and oxide layer from the surface of the nickel substrate, clean and dry to obtain a pretreated nickel substrate;

[0012] By electroplating metallic silver onto the pretreated nickel substrate and then subjecting it to overheating, a highly hydrophilic nickel-silver alloy is obtained.

[0013] In a preferred embodiment of the preparation method of the highly hydrophilic nickel-silver alloy of the present invention, the method for removing surface oil stains of the nickel substrate includes removal by alkaline solution, emulsifier or organic solvent, and the oxide layer of the nickel substrate is removed by acidic solution.

[0014] As a preferred embodiment of the preparation method of the highly hydrophilic nickel-silver alloy of the present invention, the electroplating method uses silver salt as silver source, succinimide as main complexing agent, and citric acid, ethylenediaminetetraacetic acid and sodium pyrophosphate as auxiliary complexing agents, and the electroplating is carried out in the voltage range of -0.1 to -1V.

[0015] In a preferred embodiment of the method for preparing the highly hydrophilic nickel-silver alloy of the present invention, the silver source includes one of silver sulfate, silver nitrate, or silver chloride.

[0016] In a preferred embodiment of the preparation method of the highly hydrophilic nickel-silver alloy of the present invention, the concentration of the silver source is 0.001-1 mol / L, the concentration of the main complexing agent is 0.001-1 mol / L, and the concentration of the auxiliary complexing agent is 0.001-1 mol / L.

[0017] In a preferred embodiment of the preparation method of the highly hydrophilic nickel-silver alloy of the present invention, the electroplating temperature is 20-50°C, the electroplating time is 5-30 min, and the pH is 7-10.

[0018] This invention can also deposit metallic silver on the surface of a nickel-based metal by chemical plating, including,

[0019] Using silver salt as the silver source, succinimide as the main complexing agent, tartrate, ethylenediaminetetraacetic acid, and citric acid as auxiliary complexing agents, and hypophosphite, sodium borohydride, and borane as reducing agents, chemical plating is carried out by reacting for 5–30 minutes.

[0020] In a preferred embodiment of the preparation method of the highly hydrophilic nickel-silver alloy of the present invention, the concentration of silver salt is 0.001-1 mol / L, the concentration of main complexing agent is 0.001-1 mol / L, the concentration of auxiliary complexing agent is 0.001-1 mol / L, and the concentration of reducing agent is 0.001-1 mol / L during the chemical plating process.

[0021] In a preferred embodiment of the preparation method of the highly hydrophilic nickel-silver alloy of the present invention, the overheating treatment is carried out in a reducing atmosphere or an inert atmosphere.

[0022] In a preferred embodiment of the preparation method of the highly hydrophilic nickel-silver alloy of the present invention, the overheating temperature is 200-1100°C and the overheating time is 30-480 min.

[0023] Another object of the present invention is to provide an application of a highly hydrophilic nickel-silver alloy as a heat transfer material.

[0024] Beneficial effects of this invention:

[0025] Traditional methods for preparing nickel-silver alloys often fail to achieve adequate hydrophilicity, thus limiting their application in many fields. This invention, however, utilizes a process of silver plating followed by heat treatment on a nickel substrate to produce a nickel-silver alloy with high hydrophilicity, enabling it to play a greater role in areas such as surface heat transfer. Attached Figure Description

[0026] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein:

[0027] Figure 1 The results are the water contact angle test results of the alloy surface obtained in Example 1 of this invention.

[0028] Figure 2 The results are the water contact angle test results of the alloy surface obtained in Example 2 of this invention.

[0029] Figure 3 The results are the water contact angle test results of the alloy surface obtained in Example 3 of this invention.

[0030] Figure 4 The results are the water contact angle test results of the alloy surface obtained in Example 4 of this invention.

[0031] Figure 5 The results of the water contact angle test on the alloy surface obtained in Example 5 of this invention are shown.

[0032] Figure 6 The results are the water contact angle test results of the alloy surface prepared in Comparative Example 1 of this invention.

[0033] Figure 7 The results are the water contact angle test results of the alloy surface obtained in Comparative Example 2 of this invention. Detailed Implementation

[0034] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the examples in the specification.

[0035] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0036] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0037] Example 1

[0038] 1) Using nickel mesh as the substrate, pre-treat it by using ethanol and acetone to remove surface oil and sulfuric acid to remove surface oxides;

[0039] 2) Using silver nitrate at a concentration of 0.01 mol / L as the silver source, succinimide at a concentration of 0.01 mol / L as the main complexing agent, and citric acid at a concentration of 0.01 mol / L as the auxiliary complexing agent, the nickel substrate was electroplated for 5 min at a voltage of -0.3 V, at an electroplating temperature of 25 °C and a pH of 9, to obtain a nickel substrate with a silver coating on the surface.

[0040] 3) The nickel-silver alloy of this embodiment was subjected to superheat treatment in a reducing atmosphere of 5% hydrogen and 95% argon at a temperature of 200°C for 30 minutes. The resulting alloy was named Ni-Ag@1.

[0041] The water contact angle test results of the alloy surface obtained in this embodiment are as follows: Figure 1 As shown in the figure, the surface water contact angle is 0°, indicating that the prepared nickel-silver alloy has superhydrophilicity.

[0042] Example 2

[0043] 1) Using nickel mesh as the substrate, pre-treat it by using ethanol and acetone to remove surface oil and sulfuric acid to remove surface oxides;

[0044] 2) Using silver nitrate as the silver source, succinimide as the main complexing agent, and citric acid as the auxiliary complexing agent, the concentrations of silver nitrate, succinimide, and citric acid were 0.01 mol / L. The nickel substrate was electroplated for 5 min at a voltage of -0.3 V, at a plating temperature of 25 °C, and at pH = 9, to obtain a nickel substrate with a silver coating on its surface.

[0045] 3) Heat treatment was carried out in a reducing atmosphere of 5% hydrogen and 95% argon at a temperature of 400℃ for 30 min. The resulting sample was named Ni-Ag@2.

[0046] The water contact angle test results of the alloy surface obtained in this embodiment are as follows: Figure 2 As shown in the figure, the surface water contact angle is 0°, indicating that the prepared nickel-silver alloy has superhydrophilicity.

[0047] Example 3

[0048] 1) Using nickel mesh as the substrate, pre-treat it by using ethanol and acetone to remove surface oil and sulfuric acid to remove surface oxides;

[0049] 2) Using silver nitrate as the silver source, succinimide as the main complexing agent, and citric acid as the auxiliary complexing agent, the concentrations of silver nitrate, succinimide, and citric acid were 0.01 mol / L. The nickel substrate was electroplated for 5 min at a voltage of -0.3 V, at a plating temperature of 25 °C, and at pH = 9, to obtain a nickel substrate with a silver coating on its surface.

[0050] 3) Heat treatment was carried out in a reducing atmosphere of 5% hydrogen and 95% argon at a temperature of 200℃ for 60 min. The resulting sample was named Ni-Ag@3.

[0051] The water contact angle test results of the alloy surface obtained in this embodiment are as follows: Figure 3 As shown in the figure, the surface water contact angle is 0°, indicating that the prepared nickel-silver alloy has superhydrophilicity.

[0052] Example 4

[0053] 1) Using nickel mesh as the substrate, pre-treat it by using ethanol and acetone to remove surface oil and sulfuric acid to remove surface oxides;

[0054] 2) Using silver nitrate at a concentration of 0.01 mol / L as the silver source, succinimide at a concentration of 0.01 mol / L as the main complexing agent, and citric acid at a concentration of 0.01 mol / L as the auxiliary complexing agent, the nickel substrate was electroplated for 5 min at a voltage of -0.3 V, at an electroplating temperature of 25 °C and a pH of 9, to obtain a nickel substrate with a silver coating on the surface.

[0055] 3) The nickel-silver alloy of this embodiment was obtained by superheating in a reducing atmosphere of 5% hydrogen and 95% argon at a temperature of 200°C for 15 minutes.

[0056] The surface contact angle was tested, and the results are as follows: Figure 4 As shown in the figure, the results indicate that its surface water contact angle is 72.3°, indicating high hydrophilicity.

[0057] Example 5

[0058] In this embodiment, metallic silver is deposited on the substrate surface using a chemical plating method, specifically as follows:

[0059] 1) Using nickel sheets as the substrate, pre-treat them by using ethanol and acetone to remove surface oil and sulfuric acid to remove surface oxides;

[0060] 2) Using silver chloride at a concentration of 0.1 mol / L as the silver source, succinimide at a concentration of 0.1 mol / L as the main complexing agent, citric acid at a concentration of 0.1 mol / L as the auxiliary complexing agent, and borane at a concentration of 0.1 mol / L as the reducing agent, a nickel substrate with a silver layer on its surface is obtained by electroless plating.

[0061] 3) The alloy of this embodiment is obtained by superheating in a reducing atmosphere of 5% hydrogen and 95% argon at a temperature of 200°C for 30 minutes.

[0062] The surface contact angle was tested, and the results are as follows: Figure 5 As shown in the figure, the results indicate that its surface water contact angle is 68.3°, indicating high hydrophilicity.

[0063] Comparative Example 1

[0064] The difference between this comparative example and Example 1 is that the electroplating voltage in step 2) is adjusted to -1.2V, specifically:

[0065] 1) Using nickel mesh as the substrate, pre-treat it by using ethanol and acetone to remove surface oil and sulfuric acid to remove surface oxides;

[0066] 2) Using silver nitrate at a concentration of 0.01 mol / L as the silver source, succinimide at a concentration of 0.01 mol / L as the main complexing agent, and citric acid at a concentration of 0.01 mol / L as the auxiliary complexing agent, the nickel substrate was electroplated for 5 min at a voltage of -1.2 V, at an electroplating temperature of 25 °C and a pH of 9, to obtain a nickel substrate with a silver coating on the surface.

[0067] 3) The nickel-silver alloy of this comparative example was obtained by superheating in a reducing atmosphere of 5% hydrogen and 95% argon at a temperature of 200°C for 30 minutes.

[0068] The water contact angle test results of the alloy surface prepared in this comparative example are as follows: Figure 6 As shown, the results indicate that the surface water contact angle is 109°, indicating that the prepared nickel-silver alloy is hydrophobic.

[0069] Comparative Example 2

[0070] The difference between this comparative example and Example 1 is that the overheating temperature in step 3) is adjusted to 100°C. Specifically:

[0071] 1) Using nickel mesh as the substrate, pre-treat it by using ethanol and acetone to remove surface oil and sulfuric acid to remove surface oxides;

[0072] 2) Using silver nitrate at a concentration of 0.01 mol / L as the silver source, succinimide at a concentration of 0.01 mol / L as the main complexing agent, and citric acid at a concentration of 0.01 mol / L as the auxiliary complexing agent, the nickel substrate was electroplated for 5 min at a voltage of -3V, at a plating temperature of 25℃ and a pH of 9, to obtain a nickel substrate with a silver coating on the surface.

[0073] 3) The nickel-silver alloy of this comparative example was obtained by superheating in a reducing atmosphere of 5% hydrogen and 95% argon at a temperature of 100°C for 30 minutes.

[0074] The water contact angle test results of the alloy surface prepared in this comparative example are as follows: Figure 7 As shown, the results indicate that the surface water contact angle is 103°, indicating that the prepared nickel-silver alloy is hydrophobic.

[0075] Example 7

[0076] The difference between this embodiment and Embodiment 1 is that the electroplating voltage in step 2) is adjusted to -0.6V, -0.8V, and -1V respectively, specifically:

[0077] 1) Using nickel mesh as the substrate, pre-treat it by using ethanol and acetone to remove surface oil and sulfuric acid to remove surface oxides;

[0078] 2) Using silver nitrate at a concentration of 0.01 mol / L as the silver source, succinimide at a concentration of 0.01 mol / L as the main complexing agent, and citric acid at a concentration of 0.01 mol / L as the auxiliary complexing agent, the nickel substrate was electroplated for 5 min at voltages of -0.6 V, -0.8 V, and -1 V, respectively, at an electroplating temperature of 25 °C and pH = 9, to obtain a nickel substrate with a silver coating on the surface.

[0079] 3) The nickel-silver alloy of this embodiment is obtained by superheating in a reducing atmosphere of 5% hydrogen and 95% argon at a temperature of 200°C for 30 minutes.

[0080] The hydrophilicity of the nickel-silver alloy in this embodiment was measured, and the results showed that the surface water contact angle was between 10° and 90°, exhibiting high hydrophilicity.

[0081] Example 8

[0082] The difference between this embodiment and Embodiment 1 is that the heat treatment temperatures in step 3) are adjusted to 600℃, 800℃, and 1000℃ respectively. Specifically:

[0083] 1) Using nickel mesh as the substrate, pre-treat it by using ethanol and acetone to remove surface oil and sulfuric acid to remove surface oxides;

[0084] 2) Using silver nitrate at a concentration of 0.01 mol / L as the silver source, succinimide at a concentration of 0.01 mol / L as the main complexing agent, and citric acid at a concentration of 0.01 mol / L as the auxiliary complexing agent, the nickel substrate was electroplated for 5 min at a voltage of -0.3 V, at an electroplating temperature of 25 °C and a pH of 9, to obtain a nickel substrate with a silver coating on the surface.

[0085] 3) The nickel-silver alloy of this embodiment was obtained by superheating under a reducing atmosphere of 5% hydrogen and 95% argon at temperatures of 600℃, 800℃ and 1000℃ for 30 minutes.

[0086] The hydrophilicity of the nickel-silver alloy in this embodiment was measured, and the results showed that the surface water contact angle was between 10° and 90°, exhibiting high hydrophilicity.

[0087] Example 9

[0088] The difference between this embodiment and Embodiment 1 is that the heat treatment time in step 3) is adjusted to 120 min, 240 min, and 480 min, respectively. Specifically:

[0089] 1) Using nickel mesh as the substrate, pre-treat it by using ethanol and acetone to remove surface oil and sulfuric acid to remove surface oxides;

[0090] 2) Using silver nitrate at a concentration of 0.01 mol / L as the silver source, succinimide at a concentration of 0.01 mol / L as the main complexing agent, and citric acid at a concentration of 0.01 mol / L as the auxiliary complexing agent, the nickel substrate was electroplated for 5 min at a voltage of -0.3 V, at an electroplating temperature of 25 °C and a pH of 9, to obtain a nickel substrate with a silver coating on the surface.

[0091] 3) The nickel-silver alloy of this embodiment was obtained by superheating under a reducing atmosphere of 5% hydrogen and 95% argon at a temperature of 200°C and for a time of 120 min, 240 min and 480 min, respectively.

[0092] The hydrophilicity of the nickel-silver alloy in this embodiment was measured, and the results showed that the surface water contact angle was between 10° and 90°, exhibiting high hydrophilicity.

[0093] In summary, the method of this invention overcomes the shortcomings of traditional preparation methods, which fail to achieve good hydrophilicity in nickel-silver alloys, thus limiting their use in many fields. By utilizing a process of silver plating on a nickel substrate followed by heat treatment, the resulting nickel-silver alloy exhibits high hydrophilicity. Through process control, it is even possible to achieve superhydrophilicity, enabling it to play a greater role in areas such as surface heat transfer, which is of great significance.

[0094] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A highly hydrophilic nickel-silver alloy, characterized in that: The alloy uses nickel metal as a base, with a silver coating deposited on the base surface. The water contact angle on the alloy surface is <90°. The preparation method is as follows: Remove oil and oxide layer from the surface of the nickel substrate, clean and dry to obtain a pretreated nickel substrate; By depositing metallic silver on the surface of the pretreated nickel substrate by electroplating or chemical plating, and then subjecting it to overheating, a highly hydrophilic nickel-silver alloy is obtained. The electroplating method uses silver salt as the silver source, succinimide as the main complexing agent, and citric acid as the auxiliary complexing agent, and the electroplating is carried out in the voltage range of -0.1 to -1 V. The overheating treatment temperature is 200~1100 ℃, and the overheating treatment time is 30~480 min.

2. The highly hydrophilic nickel-silver alloy as described in claim 1, characterized in that: The method for removing surface oil stains from the nickel substrate includes removal by alkaline solution, emulsifier or organic solvent, and removal of the oxide layer of the nickel substrate by acidic solution.

3. The highly hydrophilic nickel-silver alloy as described in claim 1, characterized in that: The silver source is selected from silver sulfate, silver nitrate, or silver chloride.

4. The highly hydrophilic nickel-silver alloy as described in claim 1, characterized in that: The concentration of the silver source is 0.001–1 mol / L, the concentration of the main complexing agent is 0.001–1 mol / L, and the concentration of the auxiliary complexing agent is 0.001–1 mol / L.

5. The highly hydrophilic nickel-silver alloy as described in claim 4, characterized in that: The electroplating temperature is 20~50 ℃, the electroplating time is 5~30 min, and the pH is 7~10.

6. The highly hydrophilic nickel-silver alloy as described in claim 2, characterized in that: The overheating treatment is carried out in a reducing atmosphere or an inert atmosphere.

7. The application of the highly hydrophilic nickel-silver alloy as described in claim 1 as a heat transfer material.

Images