Medium-temperature type anti-corrosion fluoroaluminate soldering flux and preparation method thereof

Abstract

The invention relates to medium-temperature type anti-corrosion fluoroaluminate soldering flux and a preparation method thereof. The soldering flux takes lithium-settling mother liquor obtained by extracting lithium from Jiangxi lepidolite as a base solution; the base solution is subjected to impurity removal to obtain a solution rich in k, Rb and Cs as a raw material solution; one or more of aluminum fluoride, potassium fluoride, rubidium fluoride and cesium fluoride are dosed and added to prepare mixed type soldering flux; the added metal salts can be extracted from the lepidolite. The lepidolite is rich in rubidium and cesium, so that the production cost of the novel soldering flux is greatly reduced, and the Jiangxi lepidolite realizes resource maximum utilization. The medium-temperature type anti-corrosion fluoroaluminate soldering flux is suitable for welding aluminum alloy and high-magnesium alloy, and has special activity on alloy with high magnesium content.

Description

technical field

[0001] The invention relates to a brazing flux, in particular to a medium-temperature anti-corrosion flux suitable for welding aluminum alloys and high-magnesium alloys and a preparation method thereof. Background technique

[0002] The brazing method is to use a material with a lower melting point than the base metal as the solder, heat the weldment and the solder to the melting point of the solder but lower than the melting temperature of the base metal, and use the wetting of the liquid solder to fill the joint gap, and the base metal Interdiffusion of materials so that the same or different alloys can be combined. It is widely used in various technical fields, from precious metals to common alloy materials, such as welding of gold and silver, welding of automobiles, heat exchanger pipes, etc.

[0003] According to the melting point of the solder used, brazing is usually divided into hard brazing and soft brazing with a limit of 450°C. In aluminum flux, ...

Examples

Embodiment 1

[0054] Preparation of brazing flux: take 1 in Table 2 # The solution is the raw material solution, quantitatively take 1000mL, weigh quantitative AlCl 3 ﹒ 6H 2 Add O1081g and KF 126.11g to the raw material solution, and then add ionized water to dissolve to make a solution. After the dissolution is completed, add 745mL of hydrofluoric acid solution drop by drop, while stirring continuously, so that the two fully react, and the flocculated slurry is filtered , washed and dried to get Rb 3 AlF 6 -RbAlF 4 -Cs 3 AlF 6 -K 3 AlF 6 Quaternary eutectic new brazing flux, then crushed and sieved to obtain 1 # sample. Control the mass ratio of RbF to 30.74wt.%, the mass ratio of KF to 20.66wt.%, AlF 3 The mass ratio is 40.85wt.%, and the mass fraction of CsF is 6.88wt.%.

Embodiment 2

[0056] Preparation of brazing flux: 2 in Table 2 # The solution is the raw material solution, quantitatively take 1000mL, weigh quantitative AlCl 3 ﹒ 6H 2 Add 3.45g of O1563.45g, 194.55g of KF and 585.55g of CsF to the raw material solution, and then add ionized water to dissolve to make a solution. After the dissolution is completed, add 1014mL of hydrofluoric acid solution drop by drop, while stirring continuously to make the two fully react , the obtained flocculation slurry was filtered, washed and dried to obtain Rb 3 AlF 6 -CsAlF 4 -Cs 3 AlF 6 -K 3 AlF 6 Quaternary eutectic new brazing flux, then crushed and sieved to obtain 2 # sample. Control the mass ratio of CsF to 40wt.%, the mass ratio of KF to 15wt.%, the mass ratio of RbF to 15wt.%, AlF 3 The mass ratio is 38.95wt.%.

Embodiment 3

[0058] Preparation of brazing flux: according to 3 in Table 2 # The solution is the raw material solution, quantitatively take 1000mL, then add LiF 12.5g, KF 143g, CsF100g and AlCl 3 ﹒ 6H 2 O 1400g was heated and stirred to dissolve, and after being completely dissolved, 774mL of hydrofluoric acid was slowly added, and at the same time, it was continuously stirred to make the two fully react, and the flocculated slurry was filtered, washed, and dried to obtain a new type of brazing flux mixed with fluoroaluminate. Then crush and sieve to obtain 3 # sample. Control the mass ratio of RbF to 24wt.%, the mass ratio of CsF to 15.5wt.%, the mass ratio of KF to 18.75wt.%, AlF 3 The mass ratio is 43wt.%, the mass fraction of NaF is 0.5wt.%, and the mass fraction of LiF is 1.5wt.%. The preparation of fluoroaluminate by using the lithium sinking mother liquor greatly shortens the process flow and reduces the production cost, which is beneficial to industrial production. The modifie...

technical field

[0001] The invention relates to a brazing flux, in particular to a medium-temperature anti-corrosion flux suitable for welding aluminum alloys and high-magnesium alloys and a preparation method thereof. Background technique

[0002] The brazing method is to use a material with a lower melting point than the base metal as the solder, heat the weldment and the solder to the melting point of the solder but lower than the melting temperature of the base metal, and use the wetting of the liquid solder to fill the joint gap, and the base metal Interdiffusion of materials so that the same or different alloys can be combined. It is widely used in various technical fields, from precious metals to common alloy materials, such as welding of gold and silver, welding of automobiles, heat exchanger pipes, etc.

[0003] According to the melting point of the solder used, brazing is usually divided into hard brazing and soft brazing with a limit of 450°C. In aluminum flux, ...

Examples

Embodiment 1

[0054] Preparation of brazing flux: take 1 in Table 2 # The solution is the raw material solution, quantitatively take 1000mL, weigh quantitative AlCl 3 ﹒ 6H 2 Add O1081g and KF 126.11g to the raw material solution, and then add ionized water to dissolve to make a solution. After the dissolution is completed, add 745mL of hydrofluoric acid solution drop by drop, while stirring continuously, so that the two fully react, and the flocculated slurry is filtered , washed and dried to get Rb 3 AlF 6 -RbAlF 4 -Cs 3 AlF 6 -K 3 AlF 6 Quaternary eutectic new brazing flux, then crushed and sieved to obtain 1 # sample. Control the mass ratio of RbF to 30.74wt.%, the mass ratio of KF to 20.66wt.%, AlF 3 The mass ratio is 40.85wt.%, and the mass fraction of CsF is 6.88wt.%.

Embodiment 2

[0056] Preparation of brazing flux: 2 in Table 2 # The solution is the raw material solution, quantitatively take 1000mL, weigh quantitative AlCl 3 ﹒ 6H 2 Add 3.45g of O1563.45g, 194.55g of KF and 585.55g of CsF to the raw material solution, and then add ionized water to dissolve to make a solution. After the dissolution is completed, add 1014mL of hydrofluoric acid solution drop by drop, while stirring continuously to make the two fully react , the obtained flocculation slurry was filtered, washed and dried to obtain Rb 3 AlF 6 -CsAlF 4 -Cs 3 AlF 6 -K 3 AlF 6 Quaternary eutectic new brazing flux, then crushed and sieved to obtain 2 # sample. Control the mass ratio of CsF to 40wt.%, the mass ratio of KF to 15wt.%, the mass ratio of RbF to 15wt.%, AlF 3 The mass ratio is 38.95wt.%.

Embodiment 3

[0058] Preparation of brazing flux: according to 3 in Table 2 # The solution is the raw material solution, quantitatively take 1000mL, then add LiF 12.5g, KF 143g, CsF100g and AlCl 3 ﹒ 6H 2 O 1400g was heated and stirred to dissolve, and after being completely dissolved, 774mL of hydrofluoric acid was slowly added, and at the same time, it was continuously stirred to make the two fully react, and the flocculated slurry was filtered, washed, and dried to obtain a new type of brazing flux mixed with fluoroaluminate. Then crush and sieve to obtain 3 # sample. Control the mass ratio of RbF to 24wt.%, the mass ratio of CsF to 15.5wt.%, the mass ratio of KF to 18.75wt.%, AlF 3 The mass ratio is 43wt.%, the mass fraction of NaF is 0.5wt.%, and the mass fraction of LiF is 1.5wt.%. The preparation of fluoroaluminate by using the lithium sinking mother liquor greatly shortens the process flow and reduces the production cost, which is beneficial to industrial production. The modifie...

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