CN-116558326-B - Heat exchanger and composite material for heat exchanger

CN116558326BCN 116558326 BCN116558326 BCN 116558326BCN-116558326-B

Abstract

The heat exchanger provided by the application is provided with a channel for fluid circulation, and comprises a substrate and a hydrophobic coating layer which is coated on at least part of the surface of the substrate, wherein the hydrophobic coating layer comprises a low-surface-energy silane material and a filler dispersed in the low-surface-energy silane material, the filler comprises at least two types of particles, and the shapes of the at least two types of particles are different. The particles with different shapes are compounded, so that the particles have good filling effect in the hydrophobic coating, the compactness of the coating is improved, the barrier effect of the hydrophobic coating on corrosive media is improved, and the corrosion resistance of the heat exchanger is improved. The composite material provided by the application comprises a solvent, a low-surface-energy silane material and a filler, wherein the filler comprises at least two particles, and the shapes of the at least two particles are different. The composite material forms an anti-corrosion coating containing particles with at least two shapes, and the anti-corrosion performance of the heat exchanger is improved.

Inventors

TANG JIANHUA
YU SHURUI
HUANG HAI
HUANG NINGJIE

Assignees

浙江三花智能控制股份有限公司

Dates

Publication Date: 20260505
Application Date: 20220127

Claims (10)

1. A heat exchanger having a channel for fluid communication, the heat exchanger comprising a substrate and a hydrophobic coating layer disposed on at least a portion of the surface of the substrate, wherein the hydrophobic coating layer comprises a low surface energy silane-based material and a filler dispersed in the low surface energy silane-based material, the filler comprising at least two particles, each of the at least two particles having a different shape, at least one of the at least two particles having an irregular shape, the at least two particles comprising a first particle and a second particle, the first particle being a regular shape particle, the second particle being an irregular shape particle; The method of manufacturing the heat exchanger comprises preparing a composite material that can be used to form the hydrophobic coating, the preparation of the composite material comprising the steps of: Weighing 96.5-99 parts of solvent, 0.5-1.5 parts of the low-surface-energy silane material, 0.5-2 parts of the first particle powder, and stirring to obtain sol A; and taking 97-99.4 parts of sol A, adding 0.5-2 parts of the first particle powder and 0.1-1 part of the second particle powder, and stirring to obtain the composite material.
2. The heat exchanger of claim 1, wherein the at least two particles are poorly soluble or poorly soluble compounds in water.
3. The heat exchanger according to claim 2, wherein at least one of the at least two types of particles has a regular shape selected from one of spherical, ellipsoidal, rod-like, needle-like, plate-like, columnar, hexahedral, tetrahedral, dendritic, and three-dimensional dendritic.
4. The heat exchanger of claim 3, wherein the at least two particles each have a different chemical composition, and the irregularly shaped particles are selected from one of aluminum oxide, zinc oxide, zirconium oxide, titanium oxide, silicon oxide, lanthanum oxide, cerium oxide, praseodymium oxide, boron nitride, and barium sulfate; the regular-shape particles are selected from one of aluminum oxide, zinc oxide, zirconium oxide, titanium oxide, silicon oxide, lanthanum oxide, cerium oxide, praseodymium oxide, boron nitride, graphene oxide, carbon nanotubes and barium sulfate.
5. The heat exchanger of claim 1, wherein the at least two types of particles each have a particle size in the range of 10 to 100 nm.
6. The heat exchanger according to claim 1, wherein at least part of the surface of at least one of the at least two particles is grafted with a hydrophobic group selected from at least one of a hydrocarbon group, a halogen atom and a nitro group.
7. The heat exchanger of claim 1, wherein the low surface energy silane-based material comprises silane having a hydrophobic group grafted to a surface thereof, the hydrophobic group being selected from at least one of a hydrocarbon group, a halogen atom, and a nitro group.
8. The heat exchanger of claim 1, wherein at least a portion of the surface of the substrate is coated with a rare earth conversion coating comprising a rare earth compound, and wherein at least a portion of the rare earth conversion coating is located between the substrate and the hydrophobic coating.
9. The heat exchanger according to any one of claims 1 to 8, wherein the heat exchanger comprises a header, fins and a plurality of heat exchange tubes, the heat exchange tubes are fixed to the header, the inner cavities of the heat exchange tubes are communicated with the inner cavities of the header, at least part of the fins are fixed between two adjacent heat exchange tubes, and the substrate comprises a substrate of at least one of the header, the heat exchange tubes and the fins.
10. A composite material for a heat exchanger is characterized by comprising a solvent, a low-surface-energy silane material and a filler, wherein the filler comprises at least two types of particles, the shapes of the at least two types of particles are different, at least one of the at least two types of particles is irregularly shaped, the at least two types of particles comprise a first type of particles and a second type of particles, the first type of particles are irregularly shaped particles, and the second type of particles are irregularly shaped particles; the preparation of the composite material comprises the following steps: weighing 96.5-99 parts of the solvent, 0.5-1.5 parts of the low-surface-energy silane material and 0.5-2 parts of the first particle powder, and stirring to obtain sol A; Taking 97-99.4 parts of sol A, adding 0.5-2 parts of the first particle powder and 0.1-1 part of the second particle powder, and stirring to obtain a composite material; The composite material also has at least one of the following technical characteristics a-f: a. The solvent is at least one selected from ethanol, methanol and isopropanol; b. The low-surface energy silane material comprises silane with a surface grafted with hydrophobic groups, wherein the hydrophobic groups are selected from at least one of hydrocarbon groups, halogen atoms and nitro groups; c. the at least two particles are poorly soluble or poorly soluble compounds in water; d. The shape of at least one of the at least two particles is a regular shape, and the regular shape is one selected from sphere, ellipsoid, rod, needle, sheet, column, hexahedron, tetrahedron, dendrite and three-dimensional dendrite; e. the particle size range of the at least two particles is 10-100 nm; f. At least part of the surface of at least one of the at least two particles is grafted with a hydrophobic group selected from at least one of a hydrocarbon group, a halogen atom and a nitro group.

Description

Heat exchanger and composite material for heat exchanger Technical Field The invention relates to the technical field of heat exchange devices, in particular to a heat exchanger and a composite material for the heat exchanger. Background In the related art, a hydrophobic sol is coated on the surface of a heat exchanger to form a hydrophobic coating. The hydrophobic coating enables the corrosive solution to have a larger contact angle on the surface of the heat exchanger, is not easy to spread, and reduces the direct contact area between the corrosive solution and the surface of the heat exchanger. In addition, the hydrophobic coating itself also has a certain barrier effect against corrosive media. Therefore, the hydrophobic coating can improve the corrosion resistance of the heat exchanger. In order to increase the compactness of the hydrophobic coating and improve the barrier effect of the hydrophobic coating, fillers can be added into the hydrophobic sol to increase the compactness of the hydrophobic coating. Currently, most studies focus on the effect of filler content on the corrosion protection of hydrophobic coatings, but less on the effect of the shape of the particles contained in the constituent fillers on the corrosion protection of hydrophobic coatings. In order to further improve the corrosion resistance of the heat exchanger, the related technology can also start from the particle shape, and improve the corrosion resistance of the heat exchanger. Disclosure of Invention The application aims to provide a heat exchanger with good corrosion resistance, and correspondingly, the application also provides a composite material for the heat exchanger. The application provides a heat exchanger with a channel for fluid circulation, comprising a substrate and a hydrophobic coating layer coated on at least part of the surface of the substrate, wherein the hydrophobic coating layer comprises a low-surface-energy silane material and a filler dispersed in the low-surface-energy silane material, and the filler comprises at least two particles, and the shapes of the at least two particles are different. The hydrophobic coating comprises a low-surface-energy silane material and a filler, wherein particles contained in the filler are filled in a network structure of the low-surface-energy silane material, and the low-surface-energy silane material is firmly combined with a heat exchanger matrix. The microporous defects or voids in low surface energy silane-based materials have a wide variety of shapes. The filler in the hydrophobic coating comprises at least two particles, the particle shapes of the at least two particles are different, and the particles with different shapes are compounded, so that the particles have good filling effect in the hydrophobic coating, the compactness of the coating is improved, the barrier effect of the hydrophobic coating on corrosive media is improved, and the corrosion resistance of the heat exchanger is improved. The application also provides a composite material for a heat exchanger, the composite material comprises a solvent, a low-surface-energy silane material and a filler, the filler comprises at least two particles, and the shapes of the at least two particles are different. The composite material of the application forms an anti-corrosion coating containing particles with at least two shapes on the surface of the heat exchanger, thereby improving the corrosion resistance of the heat exchanger. Drawings FIG. 1 is a schematic representation of the microscopic morphology of irregularly shaped particles in one embodiment of the present application; FIG. 2 is a schematic representation of the microscopic morphology of three-dimensional dendritic particles in one embodiment of the present application; FIG. 3 is a schematic view of a heat exchanger according to an embodiment of the present application; FIG. 4 is an enlarged schematic view of a portion of the assembled structure of the heat exchanger of FIG. 3; FIG. 5 is a schematic cross-sectional view of a hydrophobic coating on a surface of a heat exchanger matrix in accordance with one embodiment of the present application; FIG. 6 is a schematic cross-sectional view of a hydrophobic coating and rare earth conversion coating on the surface of a heat exchanger matrix in accordance with one embodiment of the present application; FIG. 7 is a graph showing the surface topography of the samples of comparative example 1 and comparative example 2 in a 48h salt spray test of the present application; FIG. 8 is a surface topography of samples of comparative example 1 and comparative example 2 in a 96h salt spray test of the present application; FIG. 9 shows the surface topography of the samples of example 1 and comparative example 1 in a 96h salt spray test according to the present application. Detailed Description For a better understanding of the technical solution of the present application, the following detailed description of the