CN107779030B - A method for preparing durable superamphiphobic surface of high-strength aluminum alloy - Google Patents

Abstract

The invention provides a method for preparing a durable super-amphiphobic surface of a high-strength aluminum alloy, which includes two steps of immersion treatment in a zirconium-manganese salt mixed solution and coating treatment with a hydrophobic and oleophobic sol, wherein the immersion treatment in a high-strength aluminum alloy The aluminum alloy surface constructs a film layer with a specific micro/nano structure and good protective effect. Hydrophobic and oleophobic sol coating treatment can endow the film layer with super-hydrophobic and super-oleophobic super-amphiphobic function, making the high-strength aluminum alloy have excellent self-protection properties. Cleaning, anti-corrosion, pollution resistance, drag reduction and other capabilities. The super-amphiphobic surface of the high-strength aluminum alloy prepared by the invention has good durability, and can withstand various severe tests such as high temperature and low temperature, strong acid and strong alkali, friction and wear, ultraviolet radiation, high-pressure water column impact, and immersion in strong corrosive media, and is expected to be obtained in many fields. application. The preparation method of the invention has simple process and convenient operation, and is suitable for processing high-strength aluminum alloy workpieces of various sizes and shapes.

Description

A method for preparing durable superamphiphobic surface of high-strength aluminum alloy

technical field

The invention belongs to the technical field of metal material surface treatment, and in particular relates to a method for preparing a durable super-amphiphobic surface of high-strength aluminum alloy.

Background technique

The wettability of a material surface has an important influence on its application. Superamphiphobic surface refers to a type of surface that is both superhydrophobic and superoleophobic, and the contact angles of this type of surface with water and oil are both greater than 150°. Compared with a single super-hydrophobic surface, this type of super-amphiphobic surface has a stronger self-cleaning function, and its performance in anti-corrosion, stain resistance, and drag reduction is also superior. However, due to the lower surface tension of oil phase substances than water, the preparation of such superamphiphobic surfaces is more difficult.

High-strength aluminum alloy has the advantages of light weight, high specific strength and high specific stiffness, and is widely used in various fields of national economy and national defense construction. The Al-Zn-Mg-Cu series aluminum alloy (7×××) represented by 7075 aluminum alloy is the most important series of high-strength aluminum alloy, which is mainly used in the main load-bearing structure of advanced major equipment such as aircraft, such as skin, Key parts such as bulkheads and spars. In view of the excellent self-cleaning, anti-corrosion, pollution resistance, drag reduction and other abilities of super-amphiphobic surface, the preparation of durable super-amphiphobic surface of high-strength aluminum alloy is expected to significantly improve the service of advanced major equipment composed of it in complex and harsh natural environments. Quality, greatly reducing the economic losses and casualties caused by its corrosion damage.

Although there have been a few reports on the preparation of super-amphiphobic aluminum surfaces, such as Chinese patent CN 106381492A "a method for preparing a super-amphiphobic aluminum surface" and CN 106040561A "a method for preparing aluminum flakes on a super-amphiphobic layer surface", However, high-strength aluminum alloys, especially 7××× Al-Zn-Mg-Cu alloys, contain a large number of alloy phases, resulting in very uneven microstructures, which greatly increases the difficulty of preparing durable super-amphiphobic surfaces on their surfaces. Therefore, it is of great significance to develop durable superamphiphobic surfaces for high-strength aluminum alloys, especially 7××× Al-Zn-Mg-Cu alloys.

Contents of the invention

In view of the above-mentioned deficiencies in the prior art, the purpose of the present invention is to provide a method for preparing a durable superamphiphobic surface of a high-strength aluminum alloy, especially a 7××× series Al-Zn-Mg-Cu alloy, to solve the problem of the current high-strength aluminum alloy In particular, there is a serious lack of preparation technology for the super-amphiphobic surface of the 7××× series Al-Zn-Mg-Cu alloy.

To achieve the above object, the present invention adopts the following technical solutions:

A method for preparing a durable super-amphiphobic surface of a high-strength aluminum alloy, comprising the steps of:

①Zirconium-manganese salt mixed solution soaking treatment: immerse the clean high-strength aluminum alloy workpiece in the zirconium-manganese salt mixed solution with a pH value of 2.0-4.0 and a temperature of 40-60°C for 10-30 minutes, take out the workpiece and pure water wash and dry;

The zirconium-manganese salt mixed solution is formed by mixing zirconium sulfate and manganese chloride in a molar ratio of 2 to 4:1, and the concentration is 0.05 to 0.15 mol/L when converted into zirconium sulfate; the pH value of the solution is determined by the concentration Adjust for 0.5mol/L hydrofluoric acid;

② Hydrophobic and oleophobic sol coating and curing: drop an appropriate amount of silane coupling agent KH-550 into the hydrophobic and oleophobic sol, stir rapidly and vigorously, and then evenly apply to the surface of the high-strength aluminum alloy workpiece after step ①. Place it at room temperature for 12 hours, and then dry it at 60-80°C for 4-6 hours to obtain a durable super-amphiphobic surface of high-strength aluminum alloy; wherein, the volume ratio of the added silane coupling agent KH-550 to the sol is 1:200; 0.02-0.1L sol is coated on the surface of high-strength aluminum alloy workpiece per square meter.

Further, the preparation process of the hydrophobic and oleophobic sol is: adding 0.1 to 0.3 mol of octadecyl methacrylate into 500 mL of ethylene glycol ether, and ultrasonically mixing to obtain solution A; heating solution A to 70°C , blow nitrogen, then add 0.4-0.6g of azobisisobutyronitrile to solution A, and keep stirring for 1-2 hours to obtain solution B; Put the ethylene glycol ether solution of ethoxysilane into solution B, and mix it uniformly by ultrasonic to obtain solution C; place solution C at 70°C for 2 to 4 hours to obtain a hydrophobic and oleophobic sol; the ethylene glycol ether solution The concentration of vinyltriethoxysilane in the medium is 0.1-0.3mol/L.

The high-strength aluminum alloy is a 7××× series Al-Zn-Mg-Cu aluminum alloy.

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

1. The present invention uses zirconium-manganese salt mixed solution soaking treatment to construct a film layer with a specific micro/nano structure and good protective effect on the surface of high-strength aluminum alloy, and then endows the film layer with super-hydrophobic and super-repellent properties through hydrophobic and oleophobic sol coating treatment. The super-amphiphobic function of oil makes the high-strength aluminum alloy have excellent self-cleaning, anti-corrosion, pollution resistance, drag reduction and other abilities.

2. The super-amphiphobic surface of the high-strength aluminum alloy prepared by the present invention has good durability, and can withstand various severe tests such as high temperature and low temperature, strong acid and strong alkali, friction and wear, ultraviolet radiation, high-pressure water column impact, and immersion in strong corrosive media. fields have been applied.

3. The preparation method of the present invention has simple process and convenient operation, does not require special experimental conditions such as high temperature and power supply, is suitable for processing high-strength aluminum alloy workpieces of various sizes and shapes, and is easy for large-scale industrial production.

Detailed ways

The present invention will be further described in detail below in conjunction with specific examples.

It should be noted that these examples are only used to illustrate the present invention, rather than to limit the present invention, and the simple improvement of the method under the premise of the present invention all belongs to the protection scope of the present invention.

Process the 7075 or 7B04 high-strength aluminum alloy into a workpiece with a specification of 50mm×50mm×2.0mm, and polish it with 200#, 400#, 600#, 800#, 1200# water sandpaper in turn until the surface is smooth and flat, rinse it with water and put it in acetone Ultrasonic cleaning was performed for 5 minutes to obtain a workpiece with a clean surface.

Example 1:

The surface-cleaned 7075 high-strength aluminum alloy workpiece is subjected to the following treatments in sequence:

①Zirconium-manganese salt mixed solution soaking treatment: immerse the workpiece in the zirconium-manganese salt mixed solution with a pH value of 2.0 and a temperature of 40°C for 20 minutes, take out the workpiece, wash it with pure water and dry it;

The zirconium-manganese salt mixed solution is formed by mixing zirconium sulfate and manganese chloride in a molar ratio of 4:1, converted into the content of zirconium sulfate, and the concentration is 0.10mol/L; the pH value of the solution is 0.5mol/L by concentration. L of hydrofluoric acid to adjust.

② Hydrophobic and oleophobic sol coating and curing: drop an appropriate amount of silane coupling agent KH-550 into the hydrophobic and oleophobic sol, stir rapidly and vigorously, and then evenly apply to the surface of the high-strength aluminum alloy workpiece after step ①. Place it at room temperature for 12 hours, and then dry it at 60°C for 6 hours to obtain a durable super-amphiphobic surface of 7075 high-strength aluminum alloy; wherein, the volume ratio of the added silane coupling agent KH-550 to the sol is 1:200 , each square meter of high-strength aluminum alloy workpiece surface coated with 0.1L sol.

The preparation process of the hydrophobic and oleophobic sol is as follows: add 0.2 mol of octadecyl methacrylate to 500 mL of ethylene glycol ether, and mix it by ultrasonic to obtain a solution A; heat the solution A to 70° C., and blow in nitrogen gas , then add 0.5g of azobisisobutyronitrile in solution A, and continue to stir for 1.5 hours to obtain solution B; under the condition of continuous nitrogen flow, use a constant pressure funnel to dropwise add vinyl triethyl ether with a concentration of 0.2mol/L Put the ethylene glycol ethyl ether solution of oxysilane into solution B, and ultrasonically mix to obtain solution C; place solution C at 70°C for 3 hours to obtain a hydrophobic and oleophobic sol.

The inspection procedure of high-strength aluminum alloy durability super-amphiphobic surface is as follows (other embodiments are the same):

a. Super-amphiphobic function test Using the German Dataphysics OCA20 video optical contact angle measuring instrument to measure the static contact angle and rolling angle of 2 μL water droplets (pure water) and oil droplets (n-hexane) on the surface of high-strength aluminum alloy workpieces to evaluate its hydrophobic and oleophobic function , the surface with a static contact angle greater than 150° and a rolling angle less than 10° is considered a superphobic surface, and the surface with a larger static contact angle and a smaller rolling angle has a better superphobic effect.

b. Durability test adopts high temperature and low temperature test, strong acid and strong alkali test, friction and wear test, ultraviolet radiation test, high pressure water column impact test, strong corrosive medium immersion test to test the durability of the super amphiphobic surface of high strength aluminum alloy, before and after the above test The change of the static contact angle and rolling angle of water and oil on the surface of the workpiece, if the change is less than 10°, indicates that the durability of the super amphiphobic surface of the high-strength aluminum alloy is excellent, and the smaller the change, the better the durability. The specific method is as follows:

(1) High-temperature and low-temperature test: the high-strength aluminum alloy workpiece processed by the method of the present invention is placed in 200°C (high temperature) and -100°C (low temperature) environment for 48 hours respectively, and the static state of water and oil on the surface of the workpiece before and after the high-temperature and low-temperature test is tested. Changes in contact angle and rolling angle.

(2) Strong acid and strong alkali test: the high-strength aluminum alloy workpiece processed by the inventive method was respectively immersed in 1.0mol/L nitric acid solution (pH=1) and 1.0mol/L sodium hydroxide solution (pH=14) for 48 hours , Test the changes of the static contact angle and rolling angle of water and oil on the surface of the workpiece before and after the strong acid and strong alkali test.

(3) Friction and wear test: 100# metallographic sandpaper is tiled on the desktop, and one side of the high-strength aluminum alloy workpiece after the process of the present invention contacts the sandpaper (this face is the working surface), applying a fixed pressure of 1.0kPa, dragging distance 1 meter, dragging speed 5mms- ¹ , reciprocating dragging horizontally and vertically 50 times each, test the changes of the static contact angle and rolling angle of water and oil on the surface of the workpiece before and after the friction and wear test.

(4) Ultraviolet radiation test: the high-strength aluminum alloy workpiece processed by the method of the present invention is subjected to ultraviolet radiation, the wavelength of the ultraviolet light source is 254nm, the workpiece is placed at a distance of 2 to 3 cm from the light source, and the radiation time is 48 hours, before and after the ultraviolet radiation test. Changes in the static contact angle and rolling angle of water and oil on the workpiece surface.

(5) High-pressure water column impact test The high-strength aluminum alloy workpiece processed by the inventive method is subjected to high-pressure water column impact, water pressure 200kPa, release height 1 meter, reciprocating 50 times, test the static contact of workpiece surface water and oil before and after the high-pressure water column impact test Angle, roll angle changes.

(6) strong corrosive medium immersion test immerse the high-strength aluminum alloy workpiece processed by the inventive method in the sodium chloride corrosive medium of 50 ± 5g/L with a pH value of 3.2 ± 0.1 (adjusted by glacial acetic acid) at 35 ± 2°C 720 hours, test the changes of the static contact angle and rolling angle of water and oil on the surface of the workpiece before and after the strong corrosive medium immersion test.

The above-mentioned super-amphiphobic function and its durability test results show that the surface of the 7075 high-strength aluminum alloy workpiece treated by the method of the present invention is a super-amphiphobic surface: the static contact angle and rolling angle of water droplets on the surface are 157° and 2° respectively , the static contact angle and rolling angle of oil droplets on its surface are 152° and 3° respectively; before and after high temperature and low temperature test, strong acid and strong alkali test, friction and wear test, ultraviolet radiation test, high pressure water column impact test, strong corrosive medium immersion test The changes in the static contact angle and rolling angle of water and oil on the surface of the workpiece are both less than 5°, showing excellent durability.

Example 2:

The 7B04 high-strength aluminum alloy workpiece with a clean surface is subjected to the following treatments in sequence:

①Zirconium-manganese salt mixed solution soaking treatment: immerse the workpiece in the zirconium-manganese salt mixed solution with a pH value of 4.0 and a temperature of 60°C for 10 minutes, take out the workpiece, wash it with pure water and dry it;

The zirconium-manganese salt mixed solution is formed by mixing zirconium sulfate and manganese chloride in a molar ratio of 2:1, converted into the content of zirconium sulfate, and the concentration is 0.05mol/L; the pH value of the solution is 0.5mol/L by concentration. L of hydrofluoric acid to adjust.

② Hydrophobic and oleophobic sol coating and curing: drop an appropriate amount of silane coupling agent KH-550 into the hydrophobic and oleophobic sol, stir rapidly and vigorously, and then evenly apply to the surface of the high-strength aluminum alloy workpiece after step ①. Place it at room temperature for 12 hours, and then dry it at 80°C for 4 hours to obtain a durable super-amphiphobic surface of 7B04 high-strength aluminum alloy; wherein, the volume ratio of the added silane coupling agent KH-550 to the sol is 1:200 , per square meter of high-strength aluminum alloy workpiece surface coated with 0.33L sol.

The preparation process of the hydrophobic and oleophobic sol is as follows: add 0.1 mol of octadecyl methacrylate to 500 mL of ethylene glycol ether, and mix it by ultrasonic to obtain a solution A; heat the solution A to 70° C., and blow in nitrogen gas , then add 0.4g of azobisisobutyronitrile in solution A, and continue to stir for 1 hour to obtain solution B; under the condition of continuous nitrogen flow, use a constant pressure funnel dropwise to add vinyl triethyl ether with a concentration of 0.1mol/L Put the ethylene glycol ethyl ether solution of oxysilane into solution B, and ultrasonically mix to obtain solution C; place solution C at 70°C for 2 hours to obtain a hydrophobic and oleophobic sol.

The super-amphiphobic function and its durability test results show that the surface of the 7B04 high-strength aluminum alloy workpiece processed by the method of the present invention is a super-amphiphobic surface: the static contact angle and rolling angle of water droplets on the surface are 163° and 1° respectively, The static contact angle and rolling angle of oil droplets on its surface are 156° and 2° respectively; before and after high temperature and low temperature test, strong acid and strong alkali test, friction and wear test, ultraviolet radiation test, high pressure water column impact test, strong corrosive medium immersion test Both the static contact angle and rolling angle of water and oil on the surface change less than 5°, showing excellent durability.

Example 3:

The surface-cleaned 7075 high-strength aluminum alloy workpiece is subjected to the following treatments in sequence:

①Zirconium-manganese salt mixed solution soaking treatment: immerse the workpiece in the zirconium-manganese salt mixed solution with a pH value of 3.0 and a temperature of 50°C for 30 minutes, take out the workpiece, wash it with pure water and dry it;

The zirconium-manganese salt mixed solution is formed by mixing zirconium sulfate and manganese chloride in a molar ratio of 3:1, converted into the content of zirconium sulfate, and the concentration is 0.15mol/L; the pH value of the solution is 0.5mol/L by concentration. L of hydrofluoric acid to adjust.

② Hydrophobic and oleophobic sol coating and curing: drop an appropriate amount of silane coupling agent KH-550 into the hydrophobic and oleophobic sol, stir rapidly and vigorously, and then evenly apply to the surface of the high-strength aluminum alloy workpiece after step ①. Place it at room temperature for 12 hours, and then dry it at 70°C for 5 hours to obtain a durable super-amphiphobic surface of 7075 high-strength aluminum alloy; wherein, the volume ratio of the added silane coupling agent KH-550 to the sol is 1:200 , 0.02L sol is coated on the surface of high-strength aluminum alloy workpiece per square meter.

The preparation process of the hydrophobic and oleophobic sol is as follows: add 0.3 mol of octadecyl methacrylate to 500 mL of ethylene glycol ethyl ether, and mix it by ultrasonic to obtain solution A; heat solution A to 70°C, and blow in nitrogen gas , then add 0.6g of azobisisobutyronitrile in solution A, and continue to stir for 2 hours to obtain solution B; under the condition of continuous nitrogen flow, use a constant pressure funnel dropwise to add vinyl triethyl ether with a concentration of 0.3mol/L Put the ethylene glycol ether solution of oxysilane into solution B, and mix it uniformly by ultrasonic to obtain solution C; place solution C at 70°C for 4 hours to obtain a hydrophobic and oleophobic sol.

The super-amphiphobic function and its durability test results show that the surface of the 7075 high-strength aluminum alloy workpiece processed by the method of the present invention is a super-amphiphobic surface: the static contact angle and rolling angle of water droplets on the surface are 161° and 2° respectively, The static contact angle and rolling angle of oil droplets on its surface are 154° and 3° respectively; before and after high temperature and low temperature test, strong acid and strong alkali test, friction and wear test, ultraviolet radiation test, high pressure water column impact test, strong corrosive medium immersion test Both the static contact angle and rolling angle of water and oil on the surface change less than 5°, showing excellent durability.

Example 4:

The 7B04 high-strength aluminum alloy workpiece with a clean surface is subjected to the following treatments in sequence:

①Zirconium-manganese salt mixed solution soaking treatment: immerse the workpiece in the zirconium-manganese salt mixed solution with a pH value of 3.0 and a temperature of 50°C for 20 minutes, take out the workpiece, wash it with pure water and dry it;

The zirconium-manganese salt mixed solution is formed by mixing zirconium sulfate and manganese chloride in a molar ratio of 4:1, converted into the content of zirconium sulfate, and the concentration is 0.10mol/L; the pH value of the solution is 0.5mol/L by concentration. L of hydrofluoric acid to adjust.

② Hydrophobic and oleophobic sol coating and curing: drop an appropriate amount of silane coupling agent KH-550 into the hydrophobic and oleophobic sol, stir rapidly and vigorously, and then evenly apply to the surface of the high-strength aluminum alloy workpiece after step ①. Place it at room temperature for 12 hours, and then dry it at 70°C for 5 hours to obtain a durable super-amphiphobic surface of 7B04 high-strength aluminum alloy; wherein, the volume ratio of the added silane coupling agent KH-550 to the sol is 1:200 , per square meter of high-strength aluminum alloy workpiece surface coated with 0.33L sol.

The preparation process of the hydrophobic and oleophobic sol is as follows: add 0.2 mol of octadecyl methacrylate to 500 mL of ethylene glycol ether, and mix it by ultrasonic to obtain a solution A; heat the solution A to 70° C., and blow in nitrogen gas , then add 0.5g of azobisisobutyronitrile in solution A, and continue to stir for 2 hours to obtain solution B; under the condition of continuous nitrogen flow, use a constant pressure funnel dropwise to add vinyl triethyl ether with a concentration of 0.2mol/L Put the ethylene glycol ethyl ether solution of oxysilane into solution B, and ultrasonically mix to obtain solution C; place solution C at 70°C for 3 hours to obtain a hydrophobic and oleophobic sol.

The super-amphiphobic function and its durability test results show that the surface of the 7B04 high-strength aluminum alloy workpiece processed by the method of the present invention is a super-amphiphobic surface: the static contact angle and rolling angle of water droplets on the surface are 162° and 2° respectively, The static contact angle and rolling angle of oil droplets on its surface are 155° and 3° respectively; before and after high temperature and low temperature test, strong acid and strong alkali test, friction and wear test, ultraviolet radiation test, high pressure water column impact test, strong corrosive medium immersion test Both the static contact angle and rolling angle of water and oil on the surface change less than 5°, showing excellent durability.

The above examples take 7075 and 7B04 high-strength aluminum alloys as the processing objects. It should be noted that the present invention is also applicable to other 7××× Al-Zn-Mg-Cu alloys, and also applicable to pure aluminum and non-7××× series High-strength aluminum alloy.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and other modifications or equivalent replacements based on the technical solutions of the present invention shall be covered by the claims of the present invention.

Claims (2)

1. a kind of preparation method of high strength alumin ium alloy durability super-double-hydrophobic surface, which comprises the steps of:

1. zirconium-manganese salt mixed solution immersion treatment: it is 2.0 ~ 4.0, temperature that clean high strength alumin ium alloy workpiece, which is immersed in pH value, It is 10 ~ 30 minutes in 40 ~ 60 °C of zirconiums-manganese salt mixed solution, takes out workpiece, pure water is cleaned and dried up；

By zirconium sulfate and manganese chloride, 2 ~ 4:1 is mixed the zirconium-manganese salt mixed solution in molar ratio, is converted into containing for zirconium sulfate Amount, concentration are 0.05 ~ 0.15mol/L；The solution ph is adjusted by the hydrofluoric acid that concentration is 0.5 mol/L；

2. hydrophobic oleophobic sol coating and solidification: appropriate silane resin acceptor kh-550 is added dropwise into hydrophobic oleophobic colloidal sol, it is acute rapidly Strong to stir evenly, then even application to step 1. treated high strength alumin ium alloy workpiece surface, workpiece is placed at room temperature 12 hours, 4 ~ 6 hours are dried at 60 ~ 80 DEG C to get high strength alumin ium alloy durability super-double-hydrophobic surface；Wherein, the silicon of addition The volume ratio of alkane coupling agent KH-550 and colloidal sol is 1:200；Every square metre of high strength alumin ium alloy workpiece surface coats 0.02 ~ 0.1L Colloidal sol；

The preparation section of the hydrophobic oleophobic colloidal sol are as follows: 0.1 ~ 0.3 mol octadecyl methacrylate is added to 500 In mL ethylene glycol ethyl ether, ultrasound is mixed, and obtains solution A；Solution A is heated to 70 DEG C, is passed through nitrogen, is then added in solution A Enter 0.4 ~ 0.6g azodiisobutyronitrile, persistently stirs 1 ~ 2 hour, obtain solution B；Persistently lead to nitrogen under the conditions of with constant pressure funnel by The ethylene glycol ethyl ethers ethereal solution of vinyltriethoxysilane is added dropwise into solution B in drop, and ultrasound mixes, and obtains solution C；By solution C 2 ~ 4 hours are placed at 70 DEG C to get hydrophobic oleophobic colloidal sol；The ethylene glycol ethyl ethers ethereal solution medium vinyl triethoxysilane Concentration is 0.1 ~ 0.3 mol/L.

2. a kind of preparation method of high strength alumin ium alloy durability super-double-hydrophobic surface according to claim 1, which is characterized in that The high strength alumin ium alloy is 7 ××× series A l-Zn-Mg-Cu line aluminium alloys.