CN115415700A - Electrostatic spraying aluminum soldering flux and preparation method thereof - Google Patents
Electrostatic spraying aluminum soldering flux and preparation method thereof Download PDFInfo
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- 229910052782 aluminium Inorganic materials 0.000 title claims abstract description 123
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 title claims abstract description 123
- 230000004907 flux Effects 0.000 title claims abstract description 104
- 238000005476 soldering Methods 0.000 title claims abstract description 48
- 238000007590 electrostatic spraying Methods 0.000 title claims abstract description 32
- 238000002360 preparation method Methods 0.000 title abstract description 9
- 238000007716 flux method Methods 0.000 title description 2
- 238000005219 brazing Methods 0.000 claims abstract description 51
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 25
- NROKBHXJSPEDAR-UHFFFAOYSA-M potassium fluoride Chemical compound [F-].[K+] NROKBHXJSPEDAR-UHFFFAOYSA-M 0.000 claims abstract description 22
- 239000002245 particle Substances 0.000 claims abstract description 20
- IOUCSUBTZWXKTA-UHFFFAOYSA-N dipotassium;dioxido(oxo)tin Chemical compound [K+].[K+].[O-][Sn]([O-])=O IOUCSUBTZWXKTA-UHFFFAOYSA-N 0.000 claims abstract description 19
- IRPGOXJVTQTAAN-UHFFFAOYSA-N 2,2,3,3,3-pentafluoropropanal Chemical compound FC(F)(F)C(F)(F)C=O IRPGOXJVTQTAAN-UHFFFAOYSA-N 0.000 claims abstract description 16
- KLZUFWVZNOTSEM-UHFFFAOYSA-K Aluminum fluoride Inorganic materials F[Al](F)F KLZUFWVZNOTSEM-UHFFFAOYSA-K 0.000 claims abstract description 16
- 238000002844 melting Methods 0.000 claims abstract description 14
- 230000008018 melting Effects 0.000 claims abstract description 14
- 239000011698 potassium fluoride Substances 0.000 claims abstract description 11
- 235000003270 potassium fluoride Nutrition 0.000 claims abstract description 11
- 238000006243 chemical reaction Methods 0.000 claims abstract description 8
- 239000002002 slurry Substances 0.000 claims abstract description 7
- 238000001035 drying Methods 0.000 claims abstract description 4
- 239000007921 spray Substances 0.000 claims description 16
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 claims description 10
- 239000000203 mixture Substances 0.000 claims description 8
- 238000003756 stirring Methods 0.000 claims description 8
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 claims description 4
- WNROFYMDJYEPJX-UHFFFAOYSA-K aluminium hydroxide Chemical compound [OH-].[OH-].[OH-].[Al+3] WNROFYMDJYEPJX-UHFFFAOYSA-K 0.000 claims description 4
- 238000004519 manufacturing process Methods 0.000 claims description 4
- 238000002156 mixing Methods 0.000 claims description 4
- 238000009736 wetting Methods 0.000 claims description 3
- 238000000034 method Methods 0.000 abstract description 33
- 238000005260 corrosion Methods 0.000 abstract description 8
- 230000007797 corrosion Effects 0.000 abstract description 8
- 239000004744 fabric Substances 0.000 abstract description 7
- 238000005507 spraying Methods 0.000 abstract description 7
- 238000003466 welding Methods 0.000 abstract description 7
- 230000008569 process Effects 0.000 abstract description 5
- 238000003786 synthesis reaction Methods 0.000 abstract description 3
- 239000011248 coating agent Substances 0.000 abstract 1
- 238000000576 coating method Methods 0.000 abstract 1
- 230000002194 synthesizing effect Effects 0.000 abstract 1
- 230000000052 comparative effect Effects 0.000 description 33
- 238000001179 sorption measurement Methods 0.000 description 21
- 239000000843 powder Substances 0.000 description 20
- 238000000227 grinding Methods 0.000 description 8
- 229910052751 metal Inorganic materials 0.000 description 8
- 239000002184 metal Substances 0.000 description 8
- 238000005516 engineering process Methods 0.000 description 6
- 238000005303 weighing Methods 0.000 description 6
- 238000009826 distribution Methods 0.000 description 5
- 239000000463 material Substances 0.000 description 5
- 239000000243 solution Substances 0.000 description 5
- 239000000126 substance Substances 0.000 description 5
- 238000012360 testing method Methods 0.000 description 5
- 239000010953 base metal Substances 0.000 description 4
- 238000011156 evaluation Methods 0.000 description 4
- 230000000007 visual effect Effects 0.000 description 4
- 229910045601 alloy Inorganic materials 0.000 description 3
- 239000000956 alloy Substances 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 230000005684 electric field Effects 0.000 description 3
- 239000000945 filler Substances 0.000 description 3
- 229910000838 Al alloy Inorganic materials 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 1
- CRTPOZARBMQHRY-UHFFFAOYSA-L [F-].[Al+3].[F-].[K+] Chemical compound [F-].[Al+3].[F-].[K+] CRTPOZARBMQHRY-UHFFFAOYSA-L 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 230000003213 activating effect Effects 0.000 description 1
- 230000004913 activation Effects 0.000 description 1
- 239000004411 aluminium Substances 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 239000012295 chemical reaction liquid Substances 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 230000005686 electrostatic field Effects 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 238000005304 joining Methods 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 238000007711 solidification Methods 0.000 description 1
- 230000008023 solidification Effects 0.000 description 1
- 230000002195 synergetic effect Effects 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K35/00—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting
- B23K35/22—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting characterised by the composition or nature of the material
- B23K35/36—Selection of non-metallic compositions, e.g. coatings, fluxes; Selection of soldering or welding materials, conjoint with selection of non-metallic compositions, both selections being of interest
- B23K35/3601—Selection of non-metallic compositions, e.g. coatings, fluxes; Selection of soldering or welding materials, conjoint with selection of non-metallic compositions, both selections being of interest with inorganic compounds as principal constituents
- B23K35/3603—Halide salts
- B23K35/3605—Fluorides
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K35/00—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting
- B23K35/40—Making wire or rods for soldering or welding
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Inorganic Chemistry (AREA)
- Coating By Spraying Or Casting (AREA)
Abstract
The invention provides an electrostatic spraying aluminum soldering flux and a preparation method thereof. The electrostatic spraying aluminum soldering flux comprises potassium fluoride, aluminum fluoride and potassium stannate, wherein the weight percentage of the potassium fluoride is as follows: aluminum fluoride: potassium stannate = (41.0-47.0): (52.0-58.0): (0.2 to 2.5); the melting point is 560-575 ℃; the water content is 0.0 to 0.9wt percent; the median particle diameter is 11-16 μm. The preparation method of the electrostatic spraying aluminum brazing flux adopts a chemical synthesis method: firstly, synthesizing a slurry aluminum brazing flux through a chemical reaction; then drying and crushing the slurry aluminum soldering flux; and finally, carrying out particle size classification on the crushed aluminum soldering flux by using an airflow particle size classifier to obtain a target product. The electrostatic spraying aluminum brazing flux has the characteristics of enhanced capability of removing an oxide film on the surface of aluminum and no corrosion after welding; and in the electrostatic fabric spraying process, the coating has good dispersibility, fluidity and adsorbability.
Description
Technical Field
The invention belongs to the technical field of brazing, and particularly relates to an electrostatic spraying aluminum brazing flux and a preparation method thereof.
Background
Aluminum and its alloys have become more and more widely used in modern industries due to their small specific gravity, high thermal conductivity, high rigidity, and low cost.
There are many methods and techniques for joining aluminum and its alloys. The brazing has the advantages of small deformation of base materials, accurate size, high joint strength and the like, plays an important role in the connection of aluminum and aluminum alloy, and is widely applied.
Because the surface of the aluminum and the aluminum alloy is covered by a layer of compact oxide film, aluminum soldering flux is necessary to be supplemented for the smooth soldering. Through the action of removing the oxidation film of the aluminum soldering flux, the melted aluminum soldering flux can be wetted and distributed on the base metal, and a soldered joint is formed after cooling and solidification, so that soldering is completed. Therefore, brazing aluminum and its alloys, aluminum flux is indispensable and very important!
Taking an aluminum heat exchanger in the modern automobile industry as an example, a layer of aluminum brazing filler metal is pressed and coated on the surface of a plurality of base metals. During brazing, only one layer of aluminum brazing flux is coated on the workpiece, and the workpiece is brazed by utilizing a protective atmosphere continuous tunnel furnace brazing process.
The aluminum brazing flux distribution technology is generally divided into two types: wet and dry processes. The invention relates to a corresponding electrostatic spraying material distribution technology, belonging to a dry method. The wet method and the dry method have the characteristics of distribution technology and are suitable for different conditions; different material distribution technologies have different requirements on the physical and chemical properties of the aluminum brazing flux. The aluminum brazing flux has special physical and chemical properties and can be well suitable for the electrostatic spraying cloth technology.
The electrostatic spraying equipment mainly comprises a control box, a spray gun, a powder supply barrel, a powder dispersing device, a powder conveying pipe, an air compressor and the like.
The principle and the process of the electrostatic spraying cloth technology are as follows:
firstly, a metal spray cup and a polar needle at the head of the spray gun are connected with a high-voltage cathode, and a sprayed workpiece is grounded to form an anode, so that a stronger electrostatic electric field can be formed between the metal spray cup and the polar needle.
Then, by utilizing the principle of high-voltage electrostatic corona electric field, the powder is conveyed from the powder supply barrel, the powder dispersing device and the powder conveying pipe to the metal spray cup at the head of the spray gun by compressed air. Because the metal spray cup and the electrode needle are connected with the high-voltage negative electrode, corona discharge is generated, dense negative charges are generated around the metal spray cup and the electrode needle, the powder is charged with negative charges, and enters an electrostatic field with high electric field strength.
Finally, the powder directionally flies to the surface of the grounded workpiece under the dual functions of the electrostatic attraction and the compressed air driving force, and a uniform and firm adsorption powder layer is formed on the surface, so that the electrostatic spraying and distribution of the powder are completed.
Disclosure of Invention
The invention aims to provide a novel electrostatic spraying aluminum soldering flux which is well suitable for electrostatic spraying cloth and has strong capability of removing an oxide film on the surface of aluminum during brazing. The aluminum soldering flux can overcome the problems of poor dispersibility, flowability and adsorbability of the conventional aluminum soldering flux in electrostatic spraying cloth and poor capability of removing an oxide film on the surface of aluminum in subsequent brazing.
In order to achieve the purpose, the invention adopts the following technical scheme: an electrostatic spraying aluminum soldering flux comprises potassium fluoride, aluminum fluoride and potassium stannate, and the weight percentage of the aluminum soldering flux is as follows: aluminum fluoride: potassium stannate = (41.0 to 47.0): (52.0-58.0): (0.2 to 2.5); the melting point of the electrostatic spraying aluminum soldering flux is 560-575 ℃; the water content of the electrostatic spraying aluminum soldering flux is 0.0-0.9 wt%; the median particle diameter (also called D50 particle diameter) of the electrostatic spraying aluminum soldering flux is 11-16 mu m.
According to the invention, a small amount of potassium stannate is added into a potassium fluoride-aluminum fluoride system, so that the removal capability of the aluminum soldering flux on the surface oxide films of the mother material aluminum and the aluminum soldering flux can be effectively improved. During soldering, after the aluminum soldering flux is melted, the tin in the potassium stannate can be replaced by the aluminum in the base metal and the aluminum soldering flux, and chemical activation is performed to promote the oxide film to loosen and break, so that the removal capability of the aluminum soldering flux on the oxide film is improved. However, the amount of potassium stannate added should not be too great, which would otherwise increase the melting point of the flux significantly. When the melting point of the brazing flux obviously exceeds 575 ℃, the synergistic effect between the aluminum brazing flux and the aluminum brazing filler metal is not favorably exerted, and the melting of the aluminum brazing filler metal and the wetting of a base metal are seriously disturbed.
Further, the inventors found, in further studies on the electrostatic spray cloth, that: the water content of the aluminum brazing flux is not too high, and is preferably close to no water. Therefore, on one hand, the electrification performance of the aluminum soldering flux is better; on the other hand, the aluminum soldering flux powder is easy to bond and agglomerate due to the excessively high water content, so that the spraying is discontinuous and uneven, and even the phenomenon of frequent nozzle blocking occurs. In addition, the particle size of the aluminum soldering flux is also an important influence factor, and the particle size is too small, the sphericity is not good, the aluminum soldering flux is easy to agglomerate, the flowing of the aluminum soldering flux in an electrostatic spraying conveying pipeline is influenced, so that the aluminum soldering flux is not conveyed smoothly, and further, the continuous and stable spraying cannot be carried out; the aluminum brazing flux has the advantages that the particle size is too large, the relative contact area between the aluminum brazing flux and a workpiece is reduced, the adsorption force of the aluminum brazing flux to the workpiece is weakened, the aluminum brazing flux is easy to desorb in the moving process of the workpiece, the powdering rate of the aluminum brazing flux is reduced, and the problem that an oxide film on the surface of aluminum cannot be sufficiently and completely removed easily occurs.
Preferably, in the aluminum brazing flux, the weight ratio of potassium fluoride: aluminum fluoride: potassium stannate =44.8:54.0:1.2. at this ratio, the aluminum flux has a better ability to remove oxide films on the aluminum surface.
The invention also provides a preparation method of the electrostatic spraying aluminum brazing flux, which comprises the following steps:
(1) Mixing water and potassium stannate uniformly, wherein the weight ratio of potassium stannate: water =1 (1-3), then, hydrofluoric acid solution with mass concentration of 40% is added with stirring until the reaction is completed;
(2) Wetting aluminum hydroxide with water, aluminum hydroxide: water =1 (2-3);
(3) Adding hydrofluoric acid solution with the mass concentration of 40% into the mixture obtained in the step (2) by stirring until the reaction is complete, then adding the mixture obtained in the step (1), and stirring and mixing uniformly;
(4) Stirring and adding a potassium hydroxide solution with the mass concentration of 30% in the step (3) until the reaction is complete to obtain a slurry aluminum soldering flux;
(5) Drying the slurry aluminum soldering flux to obtain a block aluminum soldering flux;
(6) Crushing the block aluminum brazing flux obtained in the step (5) by using a crusher to obtain powdery aluminum brazing flux;
(7) And (3) carrying out two-stage particle size classification on the powdery aluminum soldering flux obtained in the step (6) by using an airflow particle size classifier to obtain the electrostatic spraying aluminum soldering flux with the median particle size of 11-16 mu m, the water content of not more than 0.9% and the melting point of 560-575 ℃.
It should be noted that:
(1) In the step (4) of the preparation method, after the potassium hydroxide solution is added, precipitates are continuously separated out from the reaction liquid, and after the reaction is completed, the slurry aluminum brazing flux is generated;
(2) The hydrofluoric acid solution and the potassium hydroxide solution in the preparation method are corresponding aqueous solutions;
(3) The aluminum brazing flux prepared by the preparation method has no corrosivity on aluminum materials before and after welding.
Compared with the prior art, the invention has the beneficial effects that:
(1) The aluminum brazing flux has accurate and uniform chemical components, strong capability of removing an oxide film and no corrosion after welding;
(2) The aluminum brazing flux has good dispersibility, smooth flow, difficult nozzle blockage and strong continuity of spraying operation in the process of electrostatic spraying and distributing;
(3) The aluminum soldering flux has high powder applying rate on the surface of the workpiece, good uniformity, firm adsorption and difficult powder shedding.
Drawings
FIG. 1 is a graph showing the results of experiments on the ability of removing an oxide film on the surface of aluminum and the corrosion after welding of the aluminum brazing flux obtained in examples 1 to 3 and comparative examples 1 to 6.
FIG. 2 is a graph showing the effect of electrostatic spraying of the aluminum flux obtained in example 2.
FIG. 3 is a surface view of a workpiece before and after spraying with the aluminum flux of example 2.
Detailed Description
To better illustrate the objects, technical solutions and advantages of the present invention, further examples and comparative examples are provided below. It should be noted that the examples are not intended to limit the invention in any way; the related reagents and equipment related by the invention are all general knowledge in the technical field and can be purchased in the market.
Example 1
The electrostatic spraying aluminum brazing flux of the embodiment comprises the following components: aluminum fluoride: potassium stannate =45.2, 54.6, prepared by the method of claim 3 of the present invention, to obtain an electrostatic spray aluminum flux having a median particle size of 13.5 μm, a water content of 0.6%, and a melting point of 562 ℃.
Example 2
The electrostatic spraying aluminum soldering flux of the embodiment comprises the following components: aluminum fluoride: potassium stannate =44.8, 1.2, prepared by the method of claim 3 of the present invention, to obtain an electrostatic spray aluminum flux with a median particle size of 13.4 μm, a water content of 0.6%, and a melting point of 565 ℃.
Example 3
The electrostatic spraying aluminum soldering flux of the embodiment comprises the following components: aluminum fluoride: potassium stannate =44.2, 53.3, 2.5, prepared by the method of claim 3 of the present invention, to obtain an electrostatic spray aluminum brazing flux with a median particle size of 13.2 μm, a water content of 0.6%, and a melting point of 569 ℃.
Comparative example 1
The aluminum flux composition of this comparative example was potassium fluoride: aluminum fluoride =45.3, and was prepared by the method described in claim 3 of the present invention, except that in the step (1), an aluminum flux having a median particle diameter of 13.4 μm, a water content of 0.6%, and a melting point of 561 ℃.
Comparative example 2
The aluminum flux composition of this comparative example was potassium fluoride: aluminum fluoride =42.4, and was prepared by the method according to claim 3 of the present invention, except that in the step (1), the aluminum flux having a median particle diameter of 13.5 μm, a water content of 0.6%, and a melting point of 570 ℃.
Comparative example 3
The aluminum flux composition of this comparative example was potassium fluoride: aluminum fluoride =46.8, and was prepared by the method according to claim 3 of the present invention, except that in the step (1), the aluminum flux having a median particle diameter of 13.3 μm, a water content of 0.6%, and a melting point of 566 ℃.
Comparative example 4
The aluminum brazing flux of this comparative example is different from that of comparative example 1 only in the manufacturing method. The method is a physical grinding method, namely, potassium fluoride and aluminum fluoride are directly ground in a grinding machine according to a certain proportion, and then are dried, crushed and screened.
Comparative example 5
The aluminum brazing flux of this comparative example is different only in the manufacturing method as compared with comparative example 2. The method is a physical grinding method, namely, potassium fluoride and aluminum fluoride are directly ground in a grinding machine according to a proportion, and then are dried, crushed and screened.
Comparative example 6
The aluminum brazing flux of this comparative example is different from that of comparative example 3 only in the manufacturing method. The method is a physical grinding method, namely, potassium fluoride and aluminum fluoride are directly ground in a grinding machine according to a proportion, and then are dried, crushed and screened.
The performance of examples 1 to 3 and comparative examples 1 to 6 was tested with respect to the ability to remove oxide film on the surface of aluminum and the post-weld corrosion property. The experimental method used was: 0.1g of the aluminum flux test sample was centrally stacked on a pure aluminum plate of 60mm × 60mm × 0.8mm, heated with a hydrogen flame for 45 seconds, and the test sample was observed for the oxide film removing ability on the pure aluminum plate and the corrosion condition thereafter, and the specific test results are shown in fig. 1 and the results are recorded in table 1.
TABLE 1 comparison of chemical Properties of examples and comparative examples
As can be seen from fig. 1 and table 1:
(1) The aluminum brazing flux of examples 1 to 3 has a stronger ability to remove an oxide film than that of comparative examples 1 to 3. This is mainly because potassium stannate exerts a specific activating action, and the higher the content of potassium stannate, the stronger the ability to remove the oxide film.
(2) Examples 1 to 3 and comparative examples 1 to 3, both had no corrosion after welding; in contrast, in comparative examples 4 to 6, corrosion occurred after welding. This indicates that the aluminum brazing flux prepared by the chemical synthesis method is superior to the aluminum brazing flux prepared by the physical grinding method. The aluminium brazing flux prepared by the chemical synthesis method has accurate and uniform components and no corrosion after welding.
Comparative example 7
Compared with example 2, the aluminum brazing flux of the comparative example has different water content: it was found to be 1.2%.
Comparative example 8
The aluminum flux of this comparative example is different from that of example 2 only in the median particle diameter: and 8 μm.
Comparative example 9
The aluminum flux of this comparative example was 19 μm different from that of example 2 only in the median particle diameter.
The effect of example 2 and comparative examples 7-9 on electrostatically sprayed fabrics was tested. The method is mainly compared with the flow smoothness, the adsorption capacity, the adsorption uniformity and the adsorption firmness of the aluminum soldering flux powder.
And (3) testing conditions: the size of the workpiece is 740mm multiplied by 400mm; the distance between the nozzle of the spray gun and the surface of the workpiece is 260mm; the pressure of the compressed air is 0.5MPa; the spray gun voltage was 60kV and the current was 55 μ A.
The detection method of the four indexes comprises the following steps:
(1) The flow smoothness is as follows: visual method, and evaluation by scoring. A score of 4-10 is set, where a higher score indicates a smoother, less clogged mouth.
(2) Adsorption capacity: weighing method and visual method, and the weighing data is used as the scoring basis for evaluation. Before spraying, the workpiece is weighed and marked as m 0 (ii) a After spraying, reweighing and recording as m 1 (ii) a Calculate m 1 ﹣m 0 。m 1 ﹣m 0 The maximum value of (2) is 10 minutes and the minimum value is 4 minutes, and the higher the fraction is, the better the adsorption is.
(3) Adsorption uniformity: visual method, and evaluation by scoring. A score of 4-10 is set, where a higher score indicates better adsorption uniformity.
(4) Firmness of adsorption: weighing method and visual method, and the weighing data is used as the scoring basis for evaluation. And (3) flatly placing the sprayed workpiece 200mm away from the ground, falling to the ground in a free-falling body mode, and weighing the powder falling condition of the workpiece. Before the workpiece falls to the ground, weighing and recording as m 0 (ii) a After landing, weigh again and record as m 1 (ii) a Calculate | m 1 ﹣m 0 |，|m 1 ﹣m 0 The minimum value of | is 10 points and the maximum value is 4 points, and the higher the score is, the less powder fall and the firmer the adsorption are.
The results of the specific tests are detailed in fig. 2 and are reported in table 2.
TABLE 2 comparison of Electrostatic spray effects of examples and comparative examples
| Smoothness of flow | Amount of adsorption | Uniformity of adsorption | Degree of firmness of adsorption | |
| Example 2 | 9 | 10 | 10 | 9 |
| Comparative example 7 | 4 | 4 | 4 | 10 |
| Comparative example 8 | 7 | 6 | 6 | 6 |
| Comparative example 9 | 10 | 5 | 7 | 4 |
As can be seen from the results of fig. 2 and table 2:
(1) The aluminum brazing flux powder has high water content, is easy to agglomerate and has poor electrification performance, so that the flowing smoothness, the adsorption quantity and the adsorption uniformity are poor; however, the adsorption firmness is the best and may be an indication of the water-binding capacity.
(2) The aluminum brazing flux powder is too fine and has poor sphericity, and can be agglomerated sometimes, so that various indexes are common.
(3) The aluminum brazing flux powder is too coarse and has good sphericity, so that the flowing smoothness is best; however, the relative contact area with the workpiece becomes smaller, resulting in general adsorption amount and adsorption uniformity and the worst adsorption firmness.
Finally, it should be noted that: the above examples are only used to illustrate the technical solutions of the present invention and do not limit the scope of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the true spirit and scope of the present invention.
Claims (3)
1. The electrostatic spraying aluminum soldering flux is characterized by comprising the following components in percentage by weight: aluminum fluoride: potassium stannate = (41.0 to 47.0): (52.0-58.0): (0.2-2.5); the melting point of the electrostatic spraying aluminum brazing flux is 560-575 ℃; the water content of the electrostatic spraying aluminum soldering flux is 0.0-0.9 wt%; the median particle size of the electrostatic spraying aluminum soldering flux is 11-16 mu m.
2. An electrostatic spray aluminum flux as defined in claim 1 wherein the ratio of potassium fluoride: aluminum fluoride: potassium stannate = 44.8.
3. A method of making an electrostatically sprayed aluminum flux as set forth in any of claims 1 to 2, characterized by comprising the steps of:
(1) Mixing water and potassium stannate uniformly, wherein the weight ratio of potassium stannate: water =1 (1-3), then, adding hydrofluoric acid solution with mass concentration of 40% while stirring until the reaction is complete;
(2) Wetting aluminum hydroxide with water, aluminum hydroxide: water =1 (2 to 3);
(3) Adding a hydrofluoric acid solution with the mass concentration of 40% into the mixture obtained in the step (2) by stirring until the reaction is completed, then adding the mixture obtained in the step (1), and uniformly stirring and mixing the mixture;
(4) Stirring and adding a potassium hydroxide solution with the mass concentration of 30% in the step (3) until the reaction is complete to obtain a slurry aluminum soldering flux;
(5) Drying the slurry aluminum soldering flux to obtain a block aluminum soldering flux;
(6) Crushing the block aluminum soldering flux obtained in the step (5) by using a crusher to obtain powdery aluminum soldering flux;
(7) And (3) carrying out two-stage grain size classification on the powdery aluminum brazing flux obtained in the step (6) by using a flow grain size classifier to obtain the electrostatic spraying aluminum brazing flux with the median grain size of 11-16 mu m, the water content of not more than 0.9% and the melting point of 560-575 ℃.
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1125412A (en) * | 1993-06-15 | 1996-06-26 | 莱克泽技术有限公司 | A method of brazing |
| CN101486137A (en) * | 2008-12-25 | 2009-07-22 | 天津大学 | Novel insoluble aluminum brazing flux without corrosion and preparation method thereof |
| CN102423834A (en) * | 2011-09-30 | 2012-04-25 | 河海大学常州校区 | Highly-active soldering flux suitable for stepped brazing of magnesium-aluminum alloy and preparation method of highly-active soldering flux |
| CN105108371A (en) * | 2015-09-23 | 2015-12-02 | 苏州中焊超微复合材料有限公司 | Environment-friendly type self-brazing brazing filler metal |
| JP2019044247A (en) * | 2017-09-06 | 2019-03-22 | 石原ケミカル株式会社 | Heating type displacement tin plating method on aluminum base material |
| CN113242778A (en) * | 2018-12-20 | 2021-08-10 | 索尔维公司 | Brazing flux, brazing flux composition and manufacturing method |
| CN113921802A (en) * | 2021-09-30 | 2022-01-11 | 中国电子科技集团公司第十八研究所 | Aluminum alloy negative electrode material for battery, alkaline electrolyte corrosion inhibitor, preparation method and application |
-
2022
- 2022-09-27 CN CN202211181212.5A patent/CN115415700A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1125412A (en) * | 1993-06-15 | 1996-06-26 | 莱克泽技术有限公司 | A method of brazing |
| US5755374A (en) * | 1993-06-15 | 1998-05-26 | Lexor Technologies Limited | Method of brazing |
| CN101486137A (en) * | 2008-12-25 | 2009-07-22 | 天津大学 | Novel insoluble aluminum brazing flux without corrosion and preparation method thereof |
| CN102423834A (en) * | 2011-09-30 | 2012-04-25 | 河海大学常州校区 | Highly-active soldering flux suitable for stepped brazing of magnesium-aluminum alloy and preparation method of highly-active soldering flux |
| CN105108371A (en) * | 2015-09-23 | 2015-12-02 | 苏州中焊超微复合材料有限公司 | Environment-friendly type self-brazing brazing filler metal |
| JP2019044247A (en) * | 2017-09-06 | 2019-03-22 | 石原ケミカル株式会社 | Heating type displacement tin plating method on aluminum base material |
| CN113242778A (en) * | 2018-12-20 | 2021-08-10 | 索尔维公司 | Brazing flux, brazing flux composition and manufacturing method |
| CN113921802A (en) * | 2021-09-30 | 2022-01-11 | 中国电子科技集团公司第十八研究所 | Aluminum alloy negative electrode material for battery, alkaline electrolyte corrosion inhibitor, preparation method and application |
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