CN-121972864-A - Brazing flux embedded aluminum-based composite material, preparation method thereof and heat exchanger component

CN121972864ACN 121972864 ACN121972864 ACN 121972864ACN-121972864-A

Abstract

A composite material of soldering flux embedded aluminium base is prepared through mixing soldering flux powder, inorganic filler, organic adhesive and solvent to prepare soldering flux slurry, coating the soldering flux slurry on the surface of aluminium alloy substrate, drying and solidifying to form soldering flux composite film layer, and arranging the aluminium alloy substrate with soldering flux composite film layer on surface opposite to the aluminium alloy substrate with high solidus line temperature. The preparation method can avoid complex procedures in the traditional process, can also avoid the flying and pollution of the brazing flux, and improves the uniformity of brazing flux distribution and interface bonding strength. The obtained composite material has good solder spreadability, low porosity and high joint strength in the brazing process.

Inventors

WANG SHIXIN
DING YUE
ZHOU SHUDE
PENG YIFENG
PENG QIAN

Assignees

新疆众和股份有限公司
石河子众和新材料有限公司

Dates

Publication Date: 20260505
Application Date: 20260302

Claims (10)

1. The preparation method of the soldering flux embedded aluminum-based composite material is characterized by comprising the following steps of: mixing brazing flux powder, inorganic filler, organic binder and solvent to prepare brazing flux slurry; Coating the brazing flux slurry on the surface of the brazing filler metal layer aluminum alloy substrate, and drying and curing to form a brazing flux composite film layer on the surface; And (3) placing the brazing filler metal layer aluminum alloy substrate with the brazing flux composite film layer formed on the surface and the structural core layer aluminum alloy substrate oppositely, enabling the brazing flux composite film layer to be located on one side, far away from the structural core layer aluminum alloy substrate, of the brazing filler metal layer aluminum alloy substrate, performing cast rolling compounding, enabling the brazing filler metal layer aluminum alloy substrate to cover the structural core layer aluminum alloy substrate, wherein the solidus temperature of the brazing filler metal layer aluminum alloy is lower than that of the structural core layer aluminum alloy, and preparing the brazing flux embedded aluminum-based composite material.
2. The method of manufacturing according to claim 1, wherein the mass ratio of the flux powder is 40 to 60wt%, the mass ratio of the inorganic filler is 8 to 18wt%, and the mass ratio of the organic binder is 1 to 8wt%, based on the total mass of the flux slurry.
3. The method of preparation of claim 1, wherein the method of preparation meets at least one of the following conditions: (1) The flux powder comprises fluoroaluminates; (2) The inorganic filler includes at least one of aluminum silicate and aluminosilica; (3) The organic binder includes at least one of carboxymethyl cellulose, polyvinyl alcohol, polyvinyl butyral, and hydroxypropyl methyl cellulose.
4. The method of preparation of claim 1, further satisfying at least one of the following conditions: (1) The coating method comprises at least one of knife coating, extrusion coating and spray coating; (2) The drying and curing comprises a plurality of sections of drying steps with different temperatures; (3) The casting temperature is 680-720 ℃.
5. The method according to claim 4, wherein the temperature of the first stage of drying is 50 to 70 ℃, the temperature of the second stage of drying is 80 to 100 ℃, and the temperature of the third stage of drying is 150 to 260 ℃.
6. A flux embedded aluminum matrix composite material, characterized in that it is prepared by the preparation method of any one of claims 1 to 5; The brazing flux embedded aluminum-based composite material comprises a structural core layer aluminum alloy substrate and a brazing filler metal layer aluminum alloy substrate positioned on the outer side of the structural core layer, wherein brazing flux powder is embedded in the surface layer, far away from the structural core layer, of the brazing filler metal layer aluminum alloy substrate.
7. The flux embedded aluminum matrix composite of claim 6, wherein the braze layer aluminum alloy substrate comprises an aluminum silicon based alloy and the structural core aluminum alloy substrate comprises an aluminum manganese based alloy.
8. The flux embedded aluminum matrix composite of claim 6, wherein the flux composite film has an areal density of 3 g/m 2 to 10 g/m 2 .
9. A heat exchanger component comprising the flux embedded aluminum matrix composite of any one of claims 6 to 8.
10. The heat exchanger component of claim 9, wherein the heat exchanger component comprises at least one of an evaporator flat tube, a condenser fin, and a battery cooling plate.

Description

Brazing flux embedded aluminum-based composite material, preparation method thereof and heat exchanger component Technical Field The application relates to the technical field of electrochemical energy storage, in particular to a brazing flux embedded aluminum-based composite material, a preparation method thereof and a heat exchanger component. Background Aluminum alloy has become a core material for manufacturing key heat exchangers such as automobile radiators, air-conditioning condensers, aeroengine heat management components, new energy fuel cells/power cell heat exchangers and the like by virtue of low density, excellent heat conduction performance and good atmospheric corrosion resistance. However, the dense oxide film naturally formed on the surface thereof constitutes a major obstacle to the brazing process. The oxide film seriously hinders the spreading and wetting of the brazing filler metal, so that the defects of insufficient cold joint, air holes, insufficient bonding strength and the like are caused in the brazing joint, and the reliability and the service life of the heat exchanger are directly affected. At present, the industrial field mainly adopts a vacuum brazing technology to realize the connection of aluminum heat exchanger components, inhibits the regeneration of oxide films in a high vacuum environment, realizes good spreading by utilizing the low surface tension of brazing filler metal, and can obtain a high-quality joint, but the method relies on large-scale vacuum equipment, has long production period, is only suitable for small-batch and high-added-value products, and is difficult to meet the requirement of large-scale continuous production. Controlled Atmosphere Brazing (CAB) is another viable technical path, which requires flux spraying or coating under a protective atmosphere, and the structure of which is destroyed by chemical reaction of fluoride flux and oxide film. However, the technology has inherent defects that the uniformity of the coating is obviously influenced by the spraying parameters and the state of the base material, local overthickness or overthin easily occurs, brazing flux residues possibly cause corrosion, corrosion products are generated by reaction with an aluminum matrix in a high-temperature or humid environment, the cleanliness of the system is reduced, the conductivity of cooling liquid is improved, the local galvanic corrosion is further induced, the service life of the part is shortened, and in addition, the spraying process has insufficient flexibility and is difficult to integrate with the follow-up forming process efficiently. With the rapid development of new energy automobiles and fuel cell industries, heat exchangers are required to meet the requirements of high reliability, long service life and low maintenance, and brazing flux residues are required to be extremely low and uniformly distributed and are adapted to continuous production lines to realize high productivity. Therefore, it is necessary to provide a brazing technique that can overcome the limitations of the spraying process, achieve precise and uniform application of the brazing flux, and minimize harmful residues, so as to achieve the purposes of improving the reliability of the joint, adapting to efficient and continuous production, and meeting the requirements of a long-life system. Disclosure of Invention In view of the above, the present application provides a flux embedded aluminum matrix composite, a method for preparing the same, and a heat exchanger component, so as to solve the above technical problems. In order to achieve the aim, the first aspect of the application provides a preparation method of a brazing flux embedded aluminum-based composite material, which comprises the steps of mixing brazing flux powder, inorganic filler, an organic binder and a solvent to prepare brazing flux slurry, coating the brazing flux slurry on the surface of a brazing flux layer aluminum alloy substrate, drying and solidifying the brazing flux layer aluminum alloy substrate, forming a brazing flux composite film layer on the surface, placing the brazing flux layer aluminum alloy substrate, on which the brazing flux composite film layer is formed, and the structural core layer aluminum alloy substrate opposite to each other, so that the brazing flux composite film layer is located on one side, far away from the structural core layer aluminum alloy substrate, of the brazing flux layer aluminum alloy substrate, and performing cast-rolling compounding to enable the brazing flux layer aluminum alloy substrate to cover the structural core layer aluminum alloy substrate, wherein the solidus temperature of the brazing flux layer aluminum alloy is lower than that of the structural core layer aluminum alloy, and preparing the brazing flux embedded aluminum-based composite material. Based on the first aspect, in some embodiments, the mass of each component comprises, based on the total mass of the