CN108247233B - Method for preparing alkali-washing brazing flux-free or vacuum brazing sheet - Google Patents
Method for preparing alkali-washing brazing flux-free or vacuum brazing sheet Download PDFInfo
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- CN108247233B CN108247233B CN201711327691.6A CN201711327691A CN108247233B CN 108247233 B CN108247233 B CN 108247233B CN 201711327691 A CN201711327691 A CN 201711327691A CN 108247233 B CN108247233 B CN 108247233B
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- brazing
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- aluminum
- alkali
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- 238000005219 brazing Methods 0.000 title claims abstract description 103
- 238000005406 washing Methods 0.000 title claims abstract description 37
- 238000000034 method Methods 0.000 title claims abstract description 29
- 239000010410 layer Substances 0.000 claims abstract description 53
- 238000004140 cleaning Methods 0.000 claims abstract description 31
- 229910045601 alloy Inorganic materials 0.000 claims abstract description 22
- 239000000956 alloy Substances 0.000 claims abstract description 22
- 239000012792 core layer Substances 0.000 claims abstract description 21
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims abstract description 18
- 238000003466 welding Methods 0.000 claims abstract description 12
- 239000002253 acid Substances 0.000 claims abstract description 11
- 239000003513 alkali Substances 0.000 claims abstract description 11
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 9
- 238000000137 annealing Methods 0.000 claims abstract description 8
- 239000011856 silicon-based particle Substances 0.000 claims abstract description 8
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 claims abstract description 6
- 238000005266 casting Methods 0.000 claims abstract description 6
- 238000005098 hot rolling Methods 0.000 claims abstract description 6
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 claims abstract description 5
- 239000004115 Sodium Silicate Substances 0.000 claims abstract description 5
- 229910017604 nitric acid Inorganic materials 0.000 claims abstract description 5
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 claims abstract description 5
- 229910052911 sodium silicate Inorganic materials 0.000 claims abstract description 5
- KCXVZYZYPLLWCC-UHFFFAOYSA-N EDTA Chemical class OC(=O)CN(CC(O)=O)CCN(CC(O)=O)CC(O)=O KCXVZYZYPLLWCC-UHFFFAOYSA-N 0.000 claims abstract description 4
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical class CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 claims abstract description 4
- 239000003960 organic solvent Substances 0.000 claims abstract description 4
- 238000002360 preparation method Methods 0.000 claims abstract description 4
- 238000004381 surface treatment Methods 0.000 claims abstract description 4
- AEQDJSLRWYMAQI-UHFFFAOYSA-N 2,3,9,10-tetramethoxy-6,8,13,13a-tetrahydro-5H-isoquinolino[2,1-b]isoquinoline Chemical compound C1CN2CC(C(=C(OC)C=C3)OC)=C3CC2C2=C1C=C(OC)C(OC)=C2 AEQDJSLRWYMAQI-UHFFFAOYSA-N 0.000 claims abstract description 3
- 238000005097 cold rolling Methods 0.000 claims abstract description 3
- 229910000029 sodium carbonate Inorganic materials 0.000 claims abstract description 3
- FQENQNTWSFEDLI-UHFFFAOYSA-J sodium diphosphate Chemical compound [Na+].[Na+].[Na+].[Na+].[O-]P([O-])(=O)OP([O-])([O-])=O FQENQNTWSFEDLI-UHFFFAOYSA-J 0.000 claims abstract description 3
- 239000000176 sodium gluconate Substances 0.000 claims abstract description 3
- 235000012207 sodium gluconate Nutrition 0.000 claims abstract description 3
- 229940005574 sodium gluconate Drugs 0.000 claims abstract description 3
- 239000001488 sodium phosphate Substances 0.000 claims abstract description 3
- 229910000162 sodium phosphate Inorganic materials 0.000 claims abstract description 3
- 229940048086 sodium pyrophosphate Drugs 0.000 claims abstract description 3
- 235000019818 tetrasodium diphosphate Nutrition 0.000 claims abstract description 3
- 239000001577 tetrasodium phosphonato phosphate Substances 0.000 claims abstract description 3
- RYFMWSXOAZQYPI-UHFFFAOYSA-K trisodium phosphate Chemical compound [Na+].[Na+].[Na+].[O-]P([O-])([O-])=O RYFMWSXOAZQYPI-UHFFFAOYSA-K 0.000 claims abstract description 3
- 229910000838 Al alloy Inorganic materials 0.000 claims description 22
- 229910052782 aluminium Inorganic materials 0.000 claims description 19
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 18
- 239000011777 magnesium Substances 0.000 claims description 15
- 229910052749 magnesium Inorganic materials 0.000 claims description 12
- 239000000047 product Substances 0.000 claims description 12
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 claims description 10
- 239000002131 composite material Substances 0.000 claims description 10
- 229910052710 silicon Inorganic materials 0.000 claims description 10
- 239000011701 zinc Substances 0.000 claims description 10
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 8
- 239000010703 silicon Substances 0.000 claims description 8
- 229910052725 zinc Inorganic materials 0.000 claims description 7
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 claims description 6
- 229910052742 iron Inorganic materials 0.000 claims description 5
- 239000000203 mixture Substances 0.000 claims description 5
- UIIMBOGNXHQVGW-UHFFFAOYSA-M Sodium bicarbonate Chemical compound [Na+].OC([O-])=O UIIMBOGNXHQVGW-UHFFFAOYSA-M 0.000 claims description 4
- SNAAJJQQZSMGQD-UHFFFAOYSA-N aluminum magnesium Chemical compound [Mg].[Al] SNAAJJQQZSMGQD-UHFFFAOYSA-N 0.000 claims description 4
- 239000008139 complexing agent Substances 0.000 claims description 4
- -1 aluminum manganese Chemical compound 0.000 claims description 3
- 229910052797 bismuth Inorganic materials 0.000 claims description 3
- 230000000536 complexating effect Effects 0.000 claims description 3
- 239000002244 precipitate Substances 0.000 claims description 3
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 2
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 claims description 2
- 229910052802 copper Inorganic materials 0.000 claims description 2
- 239000010949 copper Substances 0.000 claims description 2
- 239000003921 oil Substances 0.000 claims description 2
- 235000017557 sodium bicarbonate Nutrition 0.000 claims description 2
- 229910000030 sodium bicarbonate Inorganic materials 0.000 claims description 2
- 239000007921 spray Substances 0.000 claims description 2
- 125000003158 alcohol group Chemical group 0.000 claims 1
- 230000007797 corrosion Effects 0.000 abstract description 7
- 238000005260 corrosion Methods 0.000 abstract description 7
- 230000000694 effects Effects 0.000 abstract description 5
- UIIMBOGNXHQVGW-DEQYMQKBSA-M Sodium bicarbonate-14C Chemical compound [Na+].O[14C]([O-])=O UIIMBOGNXHQVGW-DEQYMQKBSA-M 0.000 abstract 1
- 239000000463 material Substances 0.000 description 11
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 10
- 230000004907 flux Effects 0.000 description 10
- 239000001301 oxygen Substances 0.000 description 10
- 229910052760 oxygen Inorganic materials 0.000 description 10
- 230000000052 comparative effect Effects 0.000 description 7
- 239000002585 base Substances 0.000 description 6
- 238000006243 chemical reaction Methods 0.000 description 6
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 4
- 239000012535 impurity Substances 0.000 description 4
- 239000012298 atmosphere Substances 0.000 description 3
- 239000011159 matrix material Substances 0.000 description 3
- 239000000758 substrate Substances 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 229910000861 Mg alloy Inorganic materials 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 159000000011 group IA salts Chemical class 0.000 description 2
- 239000011261 inert gas Substances 0.000 description 2
- 238000011031 large-scale manufacturing process Methods 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 230000003472 neutralizing effect Effects 0.000 description 2
- 239000013049 sediment Substances 0.000 description 2
- 238000006557 surface reaction Methods 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- KRHYYFGTRYWZRS-UHFFFAOYSA-M Fluoride anion Chemical compound [F-] KRHYYFGTRYWZRS-UHFFFAOYSA-M 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- 150000003841 chloride salts Chemical class 0.000 description 1
- 238000004320 controlled atmosphere Methods 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 230000001627 detrimental effect Effects 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 150000002222 fluorine compounds Chemical class 0.000 description 1
- 230000004927 fusion Effects 0.000 description 1
- 239000008187 granular material Substances 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 239000000395 magnesium oxide Substances 0.000 description 1
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 1
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- SKFYTVYMYJCRET-UHFFFAOYSA-J potassium;tetrafluoroalumanuide Chemical compound [F-].[F-].[F-].[F-].[Al+3].[K+] SKFYTVYMYJCRET-UHFFFAOYSA-J 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 238000012797 qualification Methods 0.000 description 1
- 239000010731 rolling oil Substances 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 229910000679 solder Inorganic materials 0.000 description 1
- 238000010301 surface-oxidation reaction Methods 0.000 description 1
- 239000002341 toxic gas Substances 0.000 description 1
- 238000012546 transfer Methods 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
- B23K35/24—Selection of soldering or welding materials proper
- B23K35/28—Selection of soldering or welding materials proper with the principal constituent melting at less than 950 degrees C
- B23K35/286—Al as the principal constituent
- B23K35/288—Al as the principal constituent with Sn or Zn
-
- 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
- B23K1/00—Soldering, e.g. brazing, or unsoldering
- B23K1/20—Preliminary treatment of work or areas to be soldered, e.g. in respect of a galvanic coating
-
- 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
- B23K1/00—Soldering, e.g. brazing, or unsoldering
- B23K1/20—Preliminary treatment of work or areas to be soldered, e.g. in respect of a galvanic coating
- B23K1/206—Cleaning
-
- 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
- B23K35/02—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting characterised by mechanical features, e.g. shape
- B23K35/0222—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting characterised by mechanical features, e.g. shape for use in soldering, brazing
- B23K35/0233—Sheets, foils
- B23K35/0238—Sheets, foils layered
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)
Abstract
The invention discloses a preparation method of an alkali-washing brazing flux-free or vacuum brazing sheet, which comprises the following steps: the method comprises the following steps of casting an ingot by alloy casting equipment, respectively annealing a core layer and a brazing layer, then hot rolling the core layer and the brazing layer into a sheet, welding the layers together, hot rolling, then cold rolling, finally annealing, and carrying out surface treatment before welding, and comprises the following steps: (1) cleaning the surface of the alkali-washed brazing flux-free or vacuum brazing plate by using an organic solvent; (2) washing the product of the step (1) with alkali liquor: 0-5 wt% of sodium gluconate, 0-5 wt% of sodium pyrophosphate, 0-10 wt% of sodium carbonate, 0-3 wt% of sodium phosphate, 0-10 wt% of sodium bicarbonate, 0-1 wt% of NaOH and 0-5 wt% of sodium silicate; (3) washing the product of the step (2) by using a saturated EDTA solution or a saturated isopropanol solution; (4) acid washing the product obtained in the step (3) by using a nitric acid solution; (5) and (5) washing with water. The invention has less corrosion to silicon particles, less pollution, good brazing gap guarantee and good effect.
Description
Technical Field
The invention relates to a preparation method of an alkali-washing brazing flux-free or vacuum brazing sheet.
Background
The development of the flux heat transfer industry requires the lowest possible final cost to manufacture high quality materials and components, heat exchanger brazing being most often produced in an atmosphere of nitrogen and containing the least possible amount of oxygen impurities. This process is known as controlled atmosphere brazing ("CAB") and also includes Al-K-F based fluxes, such as applied Nocolok flux, which are decomposed by adding a brazing flux, dissolved to remove oxide films to form a wet, molten solder.
Post-braze flux residues, however, are generally considered to be detrimental to heat exchangers because they may spread over brazed aluminum surfaces or plugged internal channels, thereby preventing efficient heat exchange with the heat exchanger. The fluoride flux post-braze residue adheres tightly to the surface of the aluminum component, does not readily dissolve, for some complex structures such as honeycomb, complex or narrow passages in the heat exchanger, and can only be mechanically wiped off, easily retaining a large residue, and is difficult to clean completely. And in the brazing process with the brazing flux, a large amount of toxic gas is generated, and the health and safety of operators are seriously damaged. In addition, during the brazing process, the flux remaining inside the tubes accelerates the corrosion rate of the material, resulting in perforation of the heat exchanger, reducing the service life of the heat exchanger.
In the 70's of the 20 th century, vacuum or inert gas shielded brazing processes were emerging. The process utilizes the diffusion phenomenon of magnesium and the characteristic that the magnesium is easy to volatilize from the aluminum-magnesium alloy and pierce through an oxide film on the surface of the aluminum-magnesium alloy to enable the brazing filler metal to flow. The process eliminates the necessity of removing residues after the brazing of chlorides and fluorides, and reduces the influence of brazing and corrosion on aluminum alloy and heat conduction of a radiator. However, the requirements for the vacuum degree and the oxygen content of the brazing process are strict, and the development is slow for a while. In recent years, the requirements for the degree of vacuum and the oxygen content are reduced due to the addition of an intermediate layer or a covering layer and the addition of Bi and Mg elements to a brazing layer, and a fluxless brazing technology is developed and is expected by customers. However, these fluxless brazing techniques have drawbacks and need to be improved,
WO 2010052231 a1 and CN 103347643 a provide a flux-free material structure, respectively, both of which are flux-free material with the brazing layer on the outermost side, and when the oxygen content of the brazing atmosphere is high, the brazing layer contains magnesium and diffuses for a long time to form a large amount of magnesium oxide, and also to hinder the fusion of the brazing joint. In addition, although the requirements on the vacuum degree and the oxygen content are high, the requirements are that the vacuum degree and the oxygen content are several ppm, the oxygen content outside the brazing piece is several ppm, the inner part is a closed space, the outer part is equivalent to an open space, the outer space of the brazing piece is infinite relative to the inner space, so that the inner part is welded well, the outer part is oxidized seriously due to the relatively high oxygen content, a thicker oxide film is formed, the welding quality is poor, and the bottleneck problem of the prior brazing flux-free industry is solved.
In response to this problem, it is a critical need in the industry to develop a new method for reducing or eliminating the effect of oxide film. US2015053751a1 discloses a method of alkaline cleaning, but the material alloy is free of magnesium, there is no volatilization of magnesium and no reaction of several ppm of oxygen or water vapor outside the braze, it is difficult to remove the effect of oxygen in the outside space on the oxide film, resulting in braze still being unsatisfied.
Disclosure of Invention
The invention aims to provide a method for preparing alkali-washing brazing flux-free or vacuum brazing sheets, which overcomes the defects in the prior art.
The alkali-washing brazing flux-free or vacuum brazing material comprises a brazing layer and a core layer;
one side or two sides of the core layer are brazing layers;
preferably, the brazing core further comprises a brazing inner layer, wherein the brazing inner layer is arranged between the brazing layer and the core layer;
the core layer is as follows: 1xxx or 3xxx or 5xxx or 6xxx or 7 xxx;
the term 1xxx represents aluminum alloy 1-series alloys, i.e., commercially pure aluminum;
the term 3xxx stands for aluminum alloy 3-series alloys, a series of alloys with aluminum manganese as the major element;
the term 5xxx stands for aluminum alloy 5-series alloys, a series of alloys with aluminum magnesium as the major element;
the term 6xxx stands for aluminum alloy 6-series alloys, a series of alloys with aluminum, silicon, magnesium as the main element;
the term 7xxx stands for aluminum alloy 7-series alloys, a series of alloys with aluminum, zinc, magnesium, copper as the major element.
The brazing layer comprises the following components in percentage by mass:
5-15% of Si, less than 0.3% of Fe, 0-2% of Mg, 0-5% of Zn, 0-0.3% of Bi0 and the balance of aluminum;
when the brazing inner layer is arranged, the brazing inner layer comprises the following components in percentage by mass:
5-15% of Si, less than 0.3% of Fe, 0-2% of Mg, 0-5% of Zn, 0-0.3% of Bi0 and the balance of aluminum;
the brazing layer comprises the following components in percentage by mass:
si3-11%, Fe not more than 0.3%, Bi0-0.3%, Zn 0-1%, and the balance of aluminum;
preferably, the brazing layer comprises the following components in percentage by mass:
si 3-10%, Fe not more than 0.3%, Bi 0-0.2%, Zn 0-1%, and the balance of aluminum;
more preferably, the brazing layer contains the following components in percentage by mass:
4.5 to 10 percent of Si, less than or equal to 0.26 percent of Fe, 0 to 0.15 percent of Bi0, 0 to 1 percent of Zn, and the balance of aluminum;
the multi-layer aluminum alloy brazing flux-free material comprises the following components in percentage by weight:
the composite ratio of the brazing outer layer is 0.1-10%, and the preferred composite ratio is 0.2-5%;
the composite ratio of the brazing layer is 5-20%, and the preferred composite ratio is 6-12%;
the balance is the core layer composite ratio.
The composite ratio refers to the percentage of each layer of material in the aluminum alloy composite material, namely the percentage of each layer of thickness in the total thickness.
The total thickness of the alkali-washing brazing-flux-free or vacuum brazing plate is 0.1mm to 3 mm;
the preparation method of the alkali-cleaning brazing-flux-free or vacuum brazing sheet comprises the following steps:
casting an ingot by using alloy casting equipment, carrying out homogenizing annealing on the core layer and the brazing layer at 480-500 ℃ for 1-2 h respectively, then carrying out hot rolling to form a sheet, welding the layers together, carrying out hot rolling at 480-500 ℃, then carrying out cold rolling, and finally annealing, wherein the annealing temperature is 350 ℃, and the annealing time is 1-2 h, so that the product can be obtained.
The alkali-cleaning brazing-flux-free or vacuum brazing sheet is suitable for preparing a heat exchanger.
The mechanical property of the alkali-washing brazing flux-free or vacuum brazing sheet can be ensured, the possibility of alkali washing can be realized in large-scale production, the alkali-washing aluminum alloy needs economic scale, the large-scale production in batches is met, an oxide film is removed, and the condition that no brazing flux exists and good welding can be realized under the inert gas atmosphere or vacuum brazing condition is ensured.
For the aluminum alloy brazing flux-free material produced in large scale, a plurality of steps are required for treatment, rolling oil is more or less remained in the rolling process, and surface treatment is required before welding, wherein the treatment method comprises the following steps:
(1) cleaning oil stains on the surface: cleaning the surface of the alkali-washed brazing-flux-free or vacuum brazing sheet by using an organic solvent such as alcohol, acetone and the like;
(2) and (3) alkaline washing, namely washing the product in the step (1) by adopting an alkaline liquor component with the following mixture ratio: 0-5 wt% of sodium gluconate, 0-5 wt% of sodium pyrophosphate, 0-10 wt% of sodium carbonate, 0-3 wt% of sodium phosphate and 0-10 wt% of sodium bicarbonate;
then adding 0-1 wt% of NaOH and 0-5 wt% of sodium silicate, preferably the weight content of NaOH is less than 0.5%, adding sodium silicate can play a role in inhibiting corrosion, controlling reaction rate and preventing over-high alkalinity from reacting with silicon.
The cleaning temperature is 30-90 ℃, and the cleaning time is 20-90 seconds;
(3) cleaning with a complexing agent, namely performing complexing cleaning on the product in the step (2) by adopting a saturated EDTA solution or a saturated isopropanol solution;
(4) acid washing, namely, adopting nitric acid solution with weight concentration of 0.05-1% to carry out acid washing on the product obtained in the step (3), cleaning residual oxides and impurities on the surface, or neutralizing alkali;
(5) and (3) washing with water to remove acid, such as surface sediments, further cleaning the surface by a spray gun washing method during washing with water, removing surface sediments, and then cleaning the surface with alcohol.
The invention has less corrosion to silicon particles, does not generate blackening phenomenon, can remove oxide films, has more uniform surface reaction, thus the clearance of parts after stamping is more uniform, and ensures good weldability. No impurity ions are attached to the surface. The strong base cleans the corroded silicon particles, the blackening phenomenon is obviously generated by the reaction of the strong base and silicon, and a large amount of corrosion products are obviously deposited on the surface of the aluminum alloy.
The invention utilizes medium-strength alkaline salts to replace strong alkali, and thoroughly overcomes the defects of non-ideal strong alkali cleaning effect, serious pollution, high risk and the like. Because the strong base not only reacts with alumina, but also easily reacts with silicon, the strong base makes the part surface corrode very unevenly, is difficult to guarantee good brazing gap, through utilizing medium strength alkaline salt, greatly reduced basicity at first does not react with silicon, has realized the naked hourglass of silicon granule again, secondly the reaction is even, and reaction rate is not too big again, can control, has guaranteed good brazing gap.
From the actual situation, the method for cleaning the aluminum alloy brazing flux-free or vacuum brazing parts greatly improves the quality qualification rate of the brazing flux-free or vacuum brazed welding seams to more than 98 percent; the fluidity of the brazing material is also increased, through experimental comparison, alkali washing is not carried out, a surface oxidation film hinders the flow of the brazing liquid, and a T-shaped experimental welding joint is shorter; as shown in fig. 3, the oxide film severely impedes the flux flow and does not allow the flux to contact the aluminum substrate. After the alkali washing method is used, the oxide film is removed, the bare leaked silicon and the aluminum alloy matrix have lower melting points and do not have the oxide film to hinder the fluidity, and the volatilization of magnesium also promotes the flow of the brazing liquid. Therefore, the T-shaped experimental welding joint is greatly lengthened, and a good effect is achieved as shown in FIG. 4.
Drawings
FIG. 1 shows the surface morphology of an aluminum alloy substrate without alkaline cleaning according to the present invention, wherein the oxide film obscures the morphology of the aluminum alloy substrate.
FIG. 2 is a surface morphology of an aluminum alloy after alkaline cleaning, which is clearly found that the method of the present invention exposes silicon particles outside the aluminum matrix, and the silicon particles are not corroded by NaOH, and the aluminum alloy surface matrix has a clear morphology.
FIG. 3 shows the brazing performance of the alkali-free T-shaped test.
FIG. 4 is a graph of T-shape test braze performance after alkaline cleaning using the present invention.
Fig. 5 is a schematic view of a case where only one brazing layer is included.
Fig. 6 is a schematic view of a structure including two brazing layers.
Fig. 7 is a schematic view of a structure in which a brazing inner layer and a brazing layer are provided on a side including a core layer.
Fig. 8 is a schematic view of a structure in which a brazing inner layer and a brazing layer are provided on one side of a core layer and a brazing layer is provided on the other side.
Fig. 9 is a schematic view of a structure including a core layer provided with a brazing inner layer and a brazing layer on both sides.
Detailed Description
Referring to fig. 5 to 9, the alkali-wash fluxless or vacuum brazing material includes a brazing layer and a core layer, wherein the brazing layer is disposed on one side or both sides of the core layer;
preferably, the brazing core further comprises a brazing inner layer, wherein the brazing inner layer is arranged between the brazing layer and the core layer;
examples 1 to 10 and comparative examples 1 to 2
TABLE 1
The cleaning method comprises the following steps:
(1) examples 1, 3, 5, 7, 9 and comparative example 1 use alcohol, examples 2, 4, 6, 8, 10 and comparative example 2 use acetone to clean the surface of the flux-free or vacuum brazing sheet;
(2) washing the product in the step (1) by alkali by adopting the components in the mixture ratio of examples 1-10 in the table 1; then adding sodium hydroxide and sodium silicate according to the mixture ratio of the embodiment, wherein the cleaning temperature and the cleaning time are shown in the table 1;
(3) cleaning with a complexing agent, namely performing complexing cleaning on the product in the step (2) by adopting a saturated EDTA solution or a saturated isopropanol solution;
(4) acid washing, namely, carrying out acid washing on the product obtained in the step (3) by adopting a 0.1 wt% nitric acid solution, and cleaning residual oxides, impurities and neutralizing alkali on the surface;
(5) and (3) washing with water to remove acid, wherein if the flow rate is slow in the alkali washing process, the surface precipitate cannot be removed, a step of surface cleaning is added during the water washing process to remove the surface precipitate, and then the surface is cleaned with alcohol.
As can be seen from the above table, the corrosion of the examples 1-10 to silicon particles is small, the blackening phenomenon is not generated, the oxide film can be removed, the surface reaction is relatively uniform, the gaps of parts after stamping are relatively uniform, and the good weldability is ensured. Comparative example 1 is a comparative example in which no complexing agent is added, and aluminum ion precipitation on the surface affects subsequent welding, and comparative example 2 is a comparative example in which corrosive silicon particles are washed by strong base, the blackening phenomenon is obviously generated by the strong base compliance reaction, and the deposition surface is obvious.
Claims (8)
1. The preparation method of the alkali-washing brazing-flux-free or vacuum brazing sheet is characterized by comprising the following steps of: the method comprises the following steps of casting an ingot by alloy casting equipment, respectively annealing a core layer and a brazing layer, then hot rolling the core layer and the brazing layer into a sheet, welding the layers together, hot rolling, then cold rolling, finally annealing, and carrying out surface treatment before welding, and comprises the following steps:
(1) cleaning oil stains on the surface: cleaning the surface of the alkali-washed brazing flux-free or vacuum brazing plate by using an organic solvent;
(2) and (3) alkaline washing, namely washing the product in the step (1) by adopting an alkaline liquor component with the following mixture ratio: 1-5wt% of sodium gluconate, 1-5wt% of sodium pyrophosphate, 1-10wt% of sodium carbonate, 0.1-3 wt% of sodium phosphate and 0.1-10wt% of sodium bicarbonate;
then adding 0.4-1wt% of NaOH and 0.5-1wt% of sodium silicate; the cleaning temperature is 30-50 ℃, and the cleaning time is 20-50 seconds;
(3) cleaning with a complexing agent, namely performing complexing cleaning on the product in the step (2) by adopting a saturated EDTA solution or a saturated isopropanol solution;
(4) acid washing, namely, acid washing is carried out on the product obtained in the step (3) by adopting a nitric acid solution;
(5) washing with water to remove acid;
after surface treatment, silicon particles are exposed on the surface of the alkali-washed brazing-flux-free or vacuum brazing plate.
2. The method according to claim 1, wherein in step (1), the organic solvent is alcohol or acetone.
3. The method of claim 1, wherein in step (4), the product of step (3) is acid-washed with a nitric acid solution having a weight concentration of 0.05-1%.
4. The method of claim 1, wherein in step (5), the water is used to remove acid, such as surface precipitate, and the surface is further cleaned by a spray gun washing method during the water washing.
5. A method according to any one of claims 1 to 4, wherein the alkali-washed fluxless or vacuum brazing sheet comprises a brazing layer and a core layer;
one side or two sides of the core layer are brazing layers;
the core layer is as follows: 1xxx or 3xxx or 5xxx or 6xxx or 7 xxx;
the term 1xxx represents aluminum alloy 1-series alloys, i.e., commercially pure aluminum;
the term 3xxx stands for aluminum alloy 3-series alloys, a series of alloys with aluminum manganese as the major element;
the term 5xxx stands for aluminum alloy 5-series alloys, a series of alloys with aluminum magnesium as the major element;
the term 6xxx stands for aluminum alloy 6-series alloys, a series of alloys with aluminum, silicon, magnesium as the main element;
the term 7xxx stands for aluminum alloy 7-series alloys, a series of alloys with aluminum, zinc, magnesium, copper as the major element;
the brazing layer comprises the following components in percentage by mass:
5 to 15 percent of Si, less than 0.3 percent of Fe, 0 to 2 percent of Mg, 0 to 5 percent of Zn, 0 to 0.3 percent of Bi, and the balance of aluminum.
6. The method of claim 5, further comprising a braze inner layer disposed between the braze layer and the core layer.
7. The method of claim 6, wherein when provided with a braze inner layer, the braze inner layer comprises the following composition by mass percent:
5-15% of Si, less than 0.3% of Fe, 0-2% of Mg, 0-5% of Zn, 0-0.3% of Bi0 and the balance of aluminum;
the brazing layer comprises the following components in percentage by mass:
si3-11%, Fe not more than 0.3%, Bi0-0.3%, Zn 0-1%, and the balance of aluminum.
8. A method according to claim 7, characterised in that the alkali wash fluxless or vacuum brazing sheet is compounded in the following ratios:
the composite ratio of the brazing inner layer is 0.1-10%; the composite ratio of the brazing layer is 5-20%, and the balance is the composite ratio of the core layer.
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101240437A (en) * | 2008-03-20 | 2008-08-13 | 北京航空航天大学 | Method for plating zinc-nickel alloy in alkaline electroplate liquid |
| JP2009301997A (en) * | 2008-06-17 | 2009-12-24 | Calsonic Kansei Corp | Manufacturing method of heat exchanger for fuel cell |
| CN102586763A (en) * | 2012-03-21 | 2012-07-18 | 成都青元泛镁科技有限公司 | Novel chemical nickel-plating method for magnesium alloy |
| CN102618897A (en) * | 2012-04-18 | 2012-08-01 | 西南大学 | Preparation method of magnesium alloy with super-hydrophobic coating on surface |
| CN106032966A (en) * | 2015-03-18 | 2016-10-19 | 东莞新科技术研究开发有限公司 | Method for cleaning heat exchangers |
| CN106476359A (en) * | 2016-09-23 | 2017-03-08 | 上海华峰新材料研发科技有限公司 | The multilayer of ladder silicone content is nothing the material and its preparation method and application of brazing flux |
| CN106944762A (en) * | 2017-04-26 | 2017-07-14 | 上海华峰新材料研发科技有限公司 | Low magnesium multilayer aluminium alloy brazing expansion material and its application |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS526344A (en) * | 1975-07-07 | 1977-01-18 | Mitsubishi Rayon Co | Surface treatment of aluminum products |
| CA2307879C (en) * | 1997-11-12 | 2009-12-22 | F. Hoffmann-La Roche Ag | Treatment of t-helper cell type 2 mediated immune diseases |
| CN100582305C (en) * | 2008-08-05 | 2010-01-20 | 沈阳飞机工业（集团）有限公司 | Method for removing impurity aluminum in alkaline complex compound mixing solution |
| HUE053338T2 (en) * | 2012-05-04 | 2021-06-28 | Hydro Aluminium Rolled Prod | Use of an aluminium clad sheet for fluxless brazing |
| CN104630900A (en) * | 2013-11-14 | 2015-05-20 | 江苏天宇光伏科技有限公司 | Surface texturing processing method of monocrystalline silicon solar cell |
| CN104525251A (en) * | 2014-12-29 | 2015-04-22 | 河北美邦工程科技有限公司 | In-situ supported forming preparation method of titanium silicon molecular sieve composite catalyst |
-
2017
- 2017-12-13 CN CN201711327691.6A patent/CN108247233B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101240437A (en) * | 2008-03-20 | 2008-08-13 | 北京航空航天大学 | Method for plating zinc-nickel alloy in alkaline electroplate liquid |
| JP2009301997A (en) * | 2008-06-17 | 2009-12-24 | Calsonic Kansei Corp | Manufacturing method of heat exchanger for fuel cell |
| CN102586763A (en) * | 2012-03-21 | 2012-07-18 | 成都青元泛镁科技有限公司 | Novel chemical nickel-plating method for magnesium alloy |
| CN102618897A (en) * | 2012-04-18 | 2012-08-01 | 西南大学 | Preparation method of magnesium alloy with super-hydrophobic coating on surface |
| CN106032966A (en) * | 2015-03-18 | 2016-10-19 | 东莞新科技术研究开发有限公司 | Method for cleaning heat exchangers |
| CN106476359A (en) * | 2016-09-23 | 2017-03-08 | 上海华峰新材料研发科技有限公司 | The multilayer of ladder silicone content is nothing the material and its preparation method and application of brazing flux |
| CN106944762A (en) * | 2017-04-26 | 2017-07-14 | 上海华峰新材料研发科技有限公司 | Low magnesium multilayer aluminium alloy brazing expansion material and its application |
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