Medium-temperature anti-corrosion fluoroaluminate 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 flux for brazing, 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 parent material as the solder, heat the solder and solder to the melting point of the solder but lower than the melting temperature of the parent material, and use the wetting effect of the liquid solder to fill the joint gap, and the parent The technology of mutual diffusion of materials to make the same or different alloy constructions combined. It is widely used in various technical fields, from precious metals to common alloy materials, such as the welding of gold and silver, the welding of automobiles and heat exchanger pipes and so on.

[0003] According to the melting point of the solder used, brazing is usually divided into brazing and soldering with...

Examples

Embodiment 1

[0054] Preparation of flux: Take 1 in Table 2 # The solution is the raw material solution, take 1000mL quantitatively, and weigh the quantitative AlCl separately 3 ﹒ 6H 2 Add O1081g and KF 126.11g to the raw material solution, and then add ionized water to dissolve it to make a solution. After the dissolution is complete, add 745mL of hydrofluoric acid solution dropwise, while stirring continuously to make the two fully react, and the flocculated slurry is filtered. , Washing and drying to get Rb 3 AlF 6 -RbAlF 4 -Cs 3 AlF 6 -K 3 AlF 6 New quaternary eutectic 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 40.85 wt.%, and the mass fraction of CsF is 6.88 wt.%.

Embodiment 2

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

Embodiment 3

[0058] Preparation of flux: Take 3 in Table 2 # The solution is the raw material solution, take 1000mL quantitatively, and then add LiF 12.5g, KF143g, CsF100g and AlCl 3 ﹒ 6H 2 O 1400g is heated and stirred to dissolve. When it is completely dissolved, slowly add 774mL of hydrofluoric acid while stirring continuously to make the two fully react. The flocculated slurry is filtered, washed and dried to obtain a new mixed fluoroaluminate flux. Then crush and sieving to obtain 3 # sample. Control the mass ratio of RbF to 24wt.%, CsF to 15.5wt.%, KF to 18.75wt.%, AlF 3 The mass ratio is 43 wt.%, the mass fraction of NaF is 0.5 wt.%, and the mass fraction of LiF is 1.5 wt.%. The preparation of fluoroaluminate by using lithium precipitation mother liquor greatly shortens the process flow and reduces the production cost to facilitate industrial production. The modified fluoroaluminate flux has stronger corrosion resistance.

Technical field

[0001] The invention relates to a flux for brazing, 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 parent material as the solder, heat the solder and solder to the melting point of the solder but lower than the melting temperature of the parent material, and use the wetting effect of the liquid solder to fill the joint gap, and the parent The technology of mutual diffusion of materials to make the same or different alloy constructions combined. It is widely used in various technical fields, from precious metals to common alloy materials, such as the welding of gold and silver, the welding of automobiles and heat exchanger pipes and so on.

[0003] According to the melting point of the solder used, brazing is usually divided into brazing and soldering with...

Examples

Embodiment 1

[0054] Preparation of flux: Take 1 in Table 2 # The solution is the raw material solution, take 1000mL quantitatively, and weigh the quantitative AlCl separately 3 ﹒ 6H 2 Add O1081g and KF 126.11g to the raw material solution, and then add ionized water to dissolve it to make a solution. After the dissolution is complete, add 745mL of hydrofluoric acid solution dropwise, while stirring continuously to make the two fully react, and the flocculated slurry is filtered. , Washing and drying to get Rb 3 AlF 6 -RbAlF 4 -Cs 3 AlF 6 -K 3 AlF 6 New quaternary eutectic 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 40.85 wt.%, and the mass fraction of CsF is 6.88 wt.%.

Embodiment 2

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

Embodiment 3

[0058] Preparation of flux: Take 3 in Table 2 # The solution is the raw material solution, take 1000mL quantitatively, and then add LiF 12.5g, KF143g, CsF100g and AlCl 3 ﹒ 6H 2 O 1400g is heated and stirred to dissolve. When it is completely dissolved, slowly add 774mL of hydrofluoric acid while stirring continuously to make the two fully react. The flocculated slurry is filtered, washed and dried to obtain a new mixed fluoroaluminate flux. Then crush and sieving to obtain 3 # sample. Control the mass ratio of RbF to 24wt.%, CsF to 15.5wt.%, KF to 18.75wt.%, AlF 3 The mass ratio is 43 wt.%, the mass fraction of NaF is 0.5 wt.%, and the mass fraction of LiF is 1.5 wt.%. The preparation of fluoroaluminate by using lithium precipitation mother liquor greatly shortens the process flow and reduces the production cost to facilitate industrial production. The modified fluoroaluminate flux has stronger corrosion resistance.

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