Composite insulating material for cabinet type current transformer and preparation method of composite insulating material

Abstract

The invention discloses a composite insulating material for a cabinet type current transformer. The composite insulating material comprises a substrate; a Cu layer on the substrate; a CuAl layer on the Cu layer; a first Al (2-x) GdxO3 layer on the CuAl layer; an Al < 2-y > Sm < y > O < 3 > layer on the first Al < 2-x > Gd < x > O < 3 > layer; a second Al (2-z) GdzO3 layer on the Al (2-y) SmyO3 layer; and an Al2O3 layer on the second Al (2-z) Gd (z) O3 layer. According to the composite insulating material, through film layer stacking structure design and technological parameter design, the aluminum oxide layer located on the outermost layer in the composite film layers can be in an amorphous state, the oxidation resistance of the aluminum oxide film layers is greatly improved, in addition, the composite film layers also have the oxidation resistance, and therefore the composite insulating material is suitable for being used for a large-scale production line. The oxidation resistance of the epoxy resin can also be improved.

Description

Technical Field

[0001] The invention relates to the technical field of layered materials, in particular to a composite insulating material for a cabinet-type current transformer and a preparation method thereof. Background Art

[0002] The cabinet current transformer is a core device for current measurement, protection and control in the power system. It is usually integrated in the distribution cabinet, ring network cabinet or switch cabinet, and undertakes the key function of converting high voltage or large current signals into low voltage and small current signals. There are a large number of insulating materials in the cabinet current transformer. One of the main insulating materials is epoxy resin. It is well known that the cabinet current transformer may operate in a high temperature and high humidity working environment. Epoxy resin is prone to oxidation reaction in a high temperature and high humidity environment. The mechanical properties of the oxidized epoxy resin decrease and the material itself cracks, causing material failure. The traditional method is to enhance the oxidation resistance of epoxy resin by using additives, but this method has limited ability to improve the oxidation resistance of epoxy resin. It has been found that the oxidation resistance of epoxy resin can be improved by plating aluminum oxide on the surface of epoxy resin, but when plating aluminum oxide, the film layer is prone to crystalline aluminum oxide, which leads to the limited improvement of the oxidation resistance of epoxy resin by aluminum oxide film. Summary of the invention

[0003] The present invention provides a composite insulating material for a cabinet current transformer. The composite insulating material of the present invention is designed through film layer stacking structure design and process parameter design so that the outermost aluminum oxide layer in the composite film layer of the present invention can be in an amorphous state, which greatly improves the antioxidant capacity of the aluminum oxide film layer. In addition, the composite film layer of the present invention itself also has antioxidant capacity and can also improve the antioxidant property of epoxy resin.

[0004] The present invention provides a composite insulating material for a cabinet-type current transformer, wherein the composite insulating material comprises:

[0005] substrate;

[0006] Cu layer on the substrate;

[0007] A CuAl layer on the Cu layer;

[0008] The first Al on the CuAl layer 2-x G x O 3 layer;

[0009] In the first Al 2-x G x O 3 Al on the layer 2-y Sm y O3 layer;

[0010] In Al 2-y Sm y O 3 The second Al 2-z G z O 3 Layer; and

[0011] In the second Al 2-z G z O 3 Al on the layer 2 O 3 layer.

[0012] In a preferred embodiment, the first Al 2-x G x O 3 The layer is formed on the CuAl layer by the following method:

[0013] The first Al layer was deposited on the CuAl layer by magnetron sputtering. 2-x G x O 3 layer, wherein the sputtering target is Al 2-x G x O 3 Target material, wherein x=0.05-0.1, wherein the power type is RF power supply, the sputtering power is 50-100W, the sputtering voltage is 200-300V, the argon gas flow rate is 20-30sccm, and the sputtering temperature is 80-100°C.

[0014] In a preferred embodiment, Al 2-y Sm y O 3 The layer is formed on the first Al 2-x G x O 3 On the layer:

[0015] The magnetron sputtering method was used to deposit the first Al 2-x G x O 3 Al is deposited on the layer 2-y Sm y O 3 layer, wherein the sputtering target is Al 2- y Sm y O 3 Target material, wherein y=0.02-0.04, wherein the power type is RF power supply, the sputtering power is 60-120W, the sputtering voltage is 200-300V, the argon gas flow rate is 20-30sccm, and the sputtering temperature is 80-100°C.

[0016] In a preferred embodiment, the second Al 2-z G z O 3 The layer is formed on the Al 2-y Sm y O 3 On the layer:

[0017] Magnetron sputtering was used to deposit Al 2-y Sm y O 3 The second Al layer is deposited on 2-z G z O 3 layer, wherein the sputtering target is Al 2- z G z O 3 Target material, wherein z=0.12-0.16, wherein the power type is RF power supply, the sputtering power is 60-120W, the sputtering voltage is 350-500V, the argon gas flow rate is 20-30sccm, and the sputtering temperature is 80-100°C.

[0018] In a preferred embodiment, Al 2 O 3 The layer is formed on the second Al 2-z G z O 3 On the layer:

[0019] The second Al 2-z G z O 3 Al is deposited on the layer 2 O 3 layer, wherein the sputtering target is Al 2 O 3 Target material, wherein the power type is RF power supply, the sputtering power is 50-100W, the sputtering voltage is 200-300V, the argon gas flow rate is 20-30sccm, and the sputtering temperature is 130-150°C.

[0020] In a preferred embodiment, the first Al 2-x G x O 3 The thickness of the layer is 20-30nm, Al 2-y Sm y O 3 The thickness of the layer is 20-30nm, and the second Al 2-z G z O 3 The thickness of the layer is 30-40nm, Al 2 O3 The thickness of the layer is 200-300 nm.

[0021] The present invention provides a method for preparing a composite insulating material for a cabinet-type current transformer, comprising:

[0022] forming a Cu layer on a substrate;

[0023] forming a CuAl layer on the Cu layer;

[0024] The first Al layer is formed on the CuAl layer. 2-x G x O 3 layer;

[0025] In the first Al 2-x G x O 3 Al 2-y Sm y O 3 layer;

[0026] In Al 2-y Sm y O 3 The second Al 2-z G z O 3 Layer; and

[0027] In the second Al 2-z G z O 3 Al 2 O 3 layer.

[0028] In a preferred embodiment, a first Al layer is formed on the CuAl layer. 2-x G x O 3 Layers include:

[0029] The first Al layer was deposited on the CuAl layer by magnetron sputtering. 2-x G x O 3 layer, wherein the sputtering target is Al 2-x G x O 3 Target material, wherein x=0.05-0.1, wherein the power type is RF power supply, the sputtering power is 50-100W, the sputtering voltage is 200-300V, the argon gas flow rate is 20-30sccm, and the sputtering temperature is 80-100°C.

[0030] In a preferred embodiment, in the first A1 2-x G x O3 Al 2-y Sm y O 3 Layers include:

[0031] The magnetron sputtering method was used to deposit the first Al 2-x G x O 3 Al is deposited on the layer 2-y Sm y O 3 layer, wherein the sputtering target is Al 2- y Sm y O 3 Target material, wherein y=0.02-0.04, wherein the power type is RF power supply, the sputtering power is 60-120W, the sputtering voltage is 200-300V, the argon gas flow rate is 20-30sccm, and the sputtering temperature is 80-100°C.

[0032] In a preferred embodiment, in Al 2-y Sm y O 3 The second Al 2-z G z O 3 Layers include:

[0033] Magnetron sputtering was used to deposit Al 2-y Sm y O 3 The second Al layer is deposited on 2-z G z O 3 layer, wherein the sputtering target is Al 2- z G z O 3 Target material, wherein z=0.12-0.16, wherein the power type is RF power supply, the sputtering power is 60-120W, the sputtering voltage is 350-500V, the argon gas flow rate is 20-30sccm, and the sputtering temperature is 80-100°C.

[0034] Compared with the prior art, the present invention has the following advantages: the composite insulating material of the present invention, through the film layer stacking structure design and process parameter design, makes the outermost aluminum oxide layer in the composite film layer of the present invention be in an amorphous state, which greatly improves the antioxidant capacity of the aluminum oxide film layer; in addition, the composite film layer of the present invention itself also has antioxidant capacity and can also improve the antioxidant property of epoxy resin. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a schematic diagram of the membrane layer structure of an embodiment of the present invention.

[0036] Figure 2 is the XRD pattern of a position of a sample prepared through an embodiment of the present invention.

[0037] Figure 3 is the XRD pattern of another position of a sample prepared through an embodiment of the present invention.

[0038] Figure 4 is the TEM photo of a comparative example.

[0039] Figure 5 is the TEM photo of another comparative example. Detailed Embodiments

[0040] The following will describe in detail the detailed embodiments of the present invention with reference to the accompanying drawings. However, it should be understood that the protection scope of the present invention is not limited by the detailed embodiments.

[0041] Figure 1 is a schematic diagram of the film layer structure of an embodiment of the present invention. As shown in the figure, the composite insulating material for a cabinet-type current transformer of the present invention includes: a substrate, a Cu layer, a CuAl layer, a first Al 2-x Gd x O 3 layer, an Al 2-y Sm y O 3 layer, a second Al 2- z Gd z O 3 layer, and an Al 2 O 3 layer. Among them, in one example, the substrate can be an epoxy resin board. Before depositing the Cu layer, the substrate can be subjected to known pretreatment, such as surface polishing, cleaning, etc. of the substrate.

[0042] Embodiment 1

[0043] A composite insulating material for a cabinet-type current transformer is provided, including: a substrate; a Cu layer on the substrate; a CuAl layer on the Cu layer; a first Al 2-x Gd x O 3 layer on the first Al 2-x Gd x O 3 layer; an Al 2-y Sm y O 3 layer on the Al 2-y Sm y O 3 layer; a second Al2-z G z O 3 layer; and in the second Al 2-z G z O 3 Al on the layer 2 O 3 Layer. In one example, the substrate can be an epoxy resin board. Before depositing the Cu layer, the substrate can be subjected to known pretreatment, such as polishing and cleaning the substrate surface. In one example, the thickness of the Cu layer can be 10-20nm (10nm is taken in various embodiments and comparative examples of the present invention). The main function of the Cu layer is that the Cu film has good film-forming properties on the surface of the epoxy resin and can easily form a continuous crack-free film layer on the surface of the epoxy resin. Therefore, the Cu film can be used as the deposition basis for other subsequent film layers. The magnetron sputtering process of the Cu layer itself is as follows: the sputtering target material is a Cu target, wherein the power supply type is an RF power supply, the sputtering power is 100W, the sputtering voltage is 400V, the argon gas flow rate is 20-30sccm, and the sputtering temperature is 100°C. The main function of the CuAl layer is a transition layer, because Cu and Al 2-x G x O 3 The lattice parameters of the layers are quite different. If Al is plated directly on the Cu layer, 2-x G x O 3 The CuAl layer may cause excessive interfacial stress, resulting in film rupture. The plating process of the CuAl layer can be consistent with the plating process of the Cu layer. The plating process of the Cu layer and the CuAl layer itself has little effect on the effect of the present invention. In the subsequent embodiments and comparative examples, unless otherwise indicated, the plating process of the Cu layer and the CuAl layer is consistent with that of Example 1.

[0044] First Al 2-x G x O 3 The layer is formed on the CuAl layer by the following method: a first Al 2-x G x O 3 layer, wherein the sputtering target is Al 2-x G x O 3 Target material, wherein x=0.05, wherein the power source type is RF power source, the sputtering power is 50W, the sputtering voltage is 200V, the argon gas flow rate is 20sccm, and the sputtering temperature is 80°C. In one example, Al 2-x G x O 3 The target material can be purchased directly from non-ferrous metal companies. This type of target material is generally formed by powder metallurgy.

[0045] Al 2-y Sm y O 3 The layer is formed on the first Al 2-x G x O 3 On the first Al layer: magnetron sputtering 2-x G x O 3 Al is deposited on the layer 2-y Sm y O 3 layer, wherein the sputtering target is Al 2-y Sm y O 3 Target material, where y=0.02, where the power type is RF power, the sputtering power is 60W, the sputtering voltage is 200V, the argon gas flow rate is 20sccm, and the sputtering temperature is 80°C. In one example, Al 2-y Sm y O 3 The target material can be purchased directly from non-ferrous metal companies. This type of target material is generally formed by powder metallurgy.

[0046] Second Al 2-z G z O 3 The layer is formed on the Al 2-y Sm y O 3 On the layer: magnetron sputtering is used on Al 2-y Sm y O 3 The second Al layer is deposited on 2-z G z O 3 layer, wherein the sputtering target is Al 2-z G z O 3 Target material, wherein z=0.12, wherein the power type is RF power supply, the sputtering power is 60W, the sputtering voltage is 350V, the argon gas flow rate is 20sccm, and the sputtering temperature is 80°C. In one example, Al 2-z G z O 3 The target material can be purchased directly from non-ferrous metal companies. This type of target material is generally formed by powder metallurgy.

[0047] Al 2 O 3 The layer is formed on the second Al 2-z G z O 3 On the second Al layer: magnetron sputtering is used2-z G z O 3 Al is deposited on the layer 2 O 3 layer, wherein the sputtering target is Al 2 O 3 The target material is a radio frequency power source, the sputtering power is 50W, the sputtering voltage is 200V, the argon gas flow rate is 20sccm, and the sputtering temperature is 130°C. In the prior art CN218730955U, it is proposed to form amorphous Al by radio frequency sputtering. 2 O 3 However, the prior art does not disclose what process parameters can be used to form amorphous Al 2 O 3 In fact, the existing technology generally adopts the method of single atomic layer deposition to form amorphous Al 2 O 3 (For example, refer to CN108847443A), because this deposition method has a slow deposition rate and is easy to control Al 2 O 3 However, the deposition speed of magnetron sputtering itself is fast, and it is difficult to control Al during the deposition process. 2 O 3 The crystal form of Al 2 O 3 In other words, it is difficult to form a large area of ​​Al by magnetron sputtering deposition. 2 O 3 If the deposition rate is reduced to achieve the formation of a large area of ​​Al by magnetron sputtering deposition, 2 O 3 The slower deposition rate will offset the advantages of magnetron sputtering. 2 O 3 The film is amorphous Al 2 O 3 This is because the crystalline Al 2 O 3 Since there are many grain boundaries in the film, the materials in the grain boundaries are generally deviated from Al 2 O 3 This causes oxygen, water vapor and other molecules to corrode the grain boundaries faster. At this time, oxygen, water vapor and other molecules can easily corrode Al along the grain boundaries. 2 O 3 The film penetrates, and Al 2 O 3 The protective effect of the film on the epoxy resin disappears. 2 O 3The film itself loses its effect on improving the oxidation resistance of epoxy resin. The inventors of the present invention have found that if Al is formed on some rare earth doped film layers, 2 O 3 Film, then Al 2 O 3 The film is more likely to form an amorphous state, which may be due to the lattice structure of the rare earth doped film itself preventing the crystalline Al 2 O 3 Film formation; Specifically, according to the explanation of crystallization thermodynamics, the necessary condition for crystallization is the formation of crystal nuclei, but the formation of crystal nuclei requires that the Gibbs free energy of crystal nuclei is less than 0 (that is, if the Gibbs free energy of crystal nuclei is greater than 0, then crystal nuclei cannot be formed without external intervention). The Gibbs free energy of crystal nuclei is related to Al 2 O 3 The interaction between the film and the electron cloud of the rare earth doped film layer is related to the interaction between the film and the electron cloud of the rare earth doped film layer. Because crystallization is essentially a redistribution of electron cloud overlap, if the energy of electron cloud overlap after crystallization is lower than that of electron cloud overlap in the amorphous state, then a crystal nucleus will appear, otherwise no crystal nucleus will appear. The lattice structure of the rare earth doped film layer itself (and the specific electron cloud shape brought by it) may make Al in the amorphous state 2 O 3 The energy of the electron cloud overlap between the film and the rare earth doped film layer is lower. Therefore, the lattice structure of the rare earth doped film layer itself prevents the crystalline Al 2 O 3 It should be understood that the above explanation is only a possible explanation for the experimental phenomenon, and other explanations for the experimental phenomenon may also be reasonable.

[0048] First Al 2-x G x O 3 The thickness of the layer is 20nm, Al 2-y Sm y O 3 The thickness of the layer is 20nm, and the second Al 2-z G z O 3 The thickness of the layer is 30nm, Al 2 O 3 The thickness of the layer is 200 nm.

[0049] In order to verify that the method of the present invention can form amorphous Al 2 O 3 The samples were subjected to XRD experiments. Figure 2 and Figure 3 is the obtained XRD pattern. Figure 2 and Figure 3The preparation method of the sample is as follows: first, the composite insulating material of Example 1 is cut into two pieces by a mechanical cutting method, and each composite insulating material is processed as follows: first, the composite insulating material is thinned to less than 0.2 mm by mechanical means such as grinding (it should be understood that the material on one side of the substrate should be ground off), and then the composite insulating material is ion-thinned by an ion etcher until the amorphous Al 2 O 3 Substrate, Cu layer, CuAl layer, first Al 2-x G x O 3 Layer, Al 2-y Sm y O 3 Layer, second Al 2-z G z O 3 The layers are polished or etched away, and part of the amorphous Al 2 O 3 The membrane was separated and XRD test was performed on the sample. The test results of one sample are shown in Figure 2 , the test results of another sample are shown in Figure 3 It can be clearly seen from the figure that the XRD diffraction spectrum shows an obvious amorphous diffraction package and does not have any crystalline diffraction peak. Therefore, the method of the present invention can form amorphous Al 2 O 3 membrane.

[0050] The oxidation resistance test of Example 1 is carried out as follows: first, the original tensile strength of the composite insulating material just prepared is tested, and then the side of the epoxy resin coated with the film layer is contacted with potassium permanganate, the temperature is maintained at 70°C, and the oxidation time is 1000h. Then, the composite insulating material is taken out and the residual tensile strength of the composite insulating material is tested. Finally, the ratio of ((original tensile strength-residual tensile strength) / original tensile strength) is calculated and defined as the tensile strength change rate ratio. The ratio reflects the degree of oxidation of the epoxy resin. The tensile strength change rate ratio of the sample of Example 1 is 6%.

[0051] Example 2

[0052] Provided is a composite insulating material for a cabinet-type current transformer, comprising: a substrate; a Cu layer on the substrate; a CuAl layer on the Cu layer; a first Al 2-x G x O 3 Layer; in the first Al 2-x G x O 3 Al on the layer 2-y Sm y O3 Layer; in Al 2-y Sm y O 3 The second Al 2-z G z O 3 layer; and in the second Al 2-z G z O 3 Al on the layer 2 O 3 layer.

[0053] First Al 2-x G x O 3 The layer is formed on the CuAl layer by the following method: a first Al 2-x G x O 3 layer, wherein the sputtering target is Al 2-x G x O 3 Target material, wherein x=0.1, wherein the power type is RF power supply, the sputtering power is 100 W, the sputtering voltage is 300 V, the argon gas flow rate is 30 sccm, and the sputtering temperature is 100 °C.

[0054] Al 2-y Sm y O 3 The layer is formed on the first Al 2-x G x O 3 On the first Al layer: magnetron sputtering 2-x G x O 3 Al is deposited on the layer 2-y Sm y O 3 layer, wherein the sputtering target is Al 2-y Sm y O 3 target material, wherein y=0.04, wherein the power type is RF power supply, the sputtering power is 120W, the sputtering voltage is 300V, the argon gas flow rate is 30sccm, and the sputtering temperature is 100°C.

[0055] Second Al 2-z G z O 3 The layer is formed on the Al 2-y Sm y O 3 On the layer: magnetron sputtering is used on Al 2-y Sm y O3 The second Al layer is deposited on 2-z G z O 3 layer, wherein the sputtering target is Al 2-z G z O 3 Target material, wherein z=0.16, wherein the power type is RF power supply, the sputtering power is 120W, the sputtering voltage is 500V, the argon gas flow rate is 30sccm, and the sputtering temperature is 100°C.

[0056] Al 2 O 3 The layer is formed on the second Al 2-z G z O 3 On the second Al layer: magnetron sputtering is used 2-z G z O 3 Al is deposited on the layer 2 O 3 layer, wherein the sputtering target is Al 2 O 3 Target material, wherein the power type is RF power supply, the sputtering power is 100W, the sputtering voltage is 300V, the argon gas flow rate is 30sccm, and the sputtering temperature is 150°C.

[0057] First Al 2-x G x O 3 The thickness of the layer is 30nm, Al 2-y Sm y O 3 The thickness of the layer is 30nm, and the second Al 2-z G z O 3 The thickness of the layer is 40nm, Al 2 O 3 The thickness of the layer was 300 nm. The tensile strength change ratio of the sample of Example 2 was 7%.

[0058] Example 3

[0059] Provided is a composite insulating material for a cabinet-type current transformer, comprising: a substrate; a Cu layer on the substrate; a CuAl layer on the Cu layer; a first Al 2-x G x O 3 Layer; in the first Al 2-x G x O 3 Al on the layer 2-y Sm y O 3 Layer; in Al2-y Sm y O 3 The second Al 2-z G z O 3 layer; and in the second Al 2-z G z O 3 Al on the layer 2 O 3 layer.

[0060] First Al 2-x G x O 3 The layer is formed on the CuAl layer by the following method: a first Al 2-x G x O 3 layer, wherein the sputtering target is Al 2-x G x O 3 Target material, wherein x=0.07, wherein the power type is RF power supply, the sputtering power is 75W, the sputtering voltage is 250V, the argon gas flow rate is 30sccm, and the sputtering temperature is 90°C.

[0061] Al 2-y Sm y O 3 The layer is formed on the first Al 2-x G x O 3 On the first Al layer: magnetron sputtering 2-x G x O 3 Al is deposited on the layer 2-y Sm y O 3 layer, wherein the sputtering target is Al 2-y Sm y O 3 target material, wherein y=0.03, wherein the power type is RF power supply, the sputtering power is 100 W, the sputtering voltage is 250 V, the argon gas flow rate is 30 sccm, and the sputtering temperature is 90 °C.

[0062] Second Al 2-z G z O 3 The layer is formed on the Al 2-y Sm y O 3 On the layer: magnetron sputtering is used on Al 2-y Sm y O 3 The second Al layer is deposited on2-z G z O 3 layer, wherein the sputtering target is Al 2-z G z O 3 Target material, wherein z=0.14, wherein the power type is RF power supply, the sputtering power is 100W, the sputtering voltage is 400V, the argon gas flow rate is 30sccm, and the sputtering temperature is 90°C.

[0063] Al 2 O 3 The layer is formed on the second Al 2-z G z O 3 On the second Al layer: magnetron sputtering is used 2-z G z O 3 Al is deposited on the layer 2 O 3 layer, wherein the sputtering target is Al 2 O 3 Target material, wherein the power type is RF power supply, the sputtering power is 70W, the sputtering voltage is 250V, the argon gas flow rate is 30sccm, and the sputtering temperature is 140°C.

[0064] First Al 2-x G x O 3 The thickness of the layer is 25nm, Al 2-y Sm y O 3 The thickness of the layer is 25nm, and the second Al 2-z G z O 3 The thickness of the layer is 35nm, Al 2 O 3 The thickness of the layer was 250 nm. The tensile strength change ratio of the sample of Example 1 was 6%.

[0065] Comparative Example 1

[0066] The composite insulating material does not include the Cu layer on the substrate, and the CuAl layer is directly formed on the substrate, and other process parameters refer to Example 1. Obvious cracks can be observed on the obtained composite insulating material.

[0067] Comparative Example 2

[0068] The composite insulating material does not include a CuAl layer, and other process parameters refer to Example 1. Obvious cracks can be observed on the obtained composite insulating material.

[0069] Comparative Example 3

[0070] Composite insulating materials include: substrate, Cu layer, CuAl layer, Al 2-y Sm y O 3 Layer, second Al 2-z G z O 3 Layer and Al 2 O 3 The other process parameters refer to Example 1. The tensile strength change ratio of the sample in Comparative Example 3 is 13%. The reason for the change in the tensile strength change ratio is that Al 2 O 3 In order to verify this conclusion, the present invention conducted a TEM test on the sample of Comparative Example 3, and the results are as follows: Figure 4 As shown, the TEM photo clearly shows the crystal grains (i.e. black dots, if it is amorphous Al 2 O 3 The film will not have any contrast change in the TEM image, and should be uniformly gray. The grain size in the image is about 10nm. The reason for the formation of crystallization is that due to the lack of the first Al 2-x G x O 3 layer, which leads to the second Al 2- z G z O 3 The lattice structure and electron cloud overlap of the layer change. At this time, the amorphous Al 2 O 3 Film and second Al 2-z G z O 3 When the layers come into contact, the overlap of the electron clouds of the two may not be in the lowest energy state, so Al 2 O 3 The film may be crystallized.

[0071] Comparative Example 4

[0072] The composite insulating material includes: a substrate, a Cu layer, a CuAl layer, a first Al 2-x G x O 3 Layer, second Al 2-z G z O 3 Layer and Al 2 O 3 The other process parameters refer to Example 1. The tensile strength change rate ratio of the sample of Comparative Example 4 is 15%.

[0073] Comparative Example 5

[0074] The composite insulating material includes: a substrate, a Cu layer, a CuAl layer, a first Al2-x G x O 3 Layer, Al 2-y Sm y O 3 Layer, second Al 2- z G z O 3 Layer and Al 2 O 3 The other process parameters refer to Example 1. The tensile strength change ratio of the sample in Comparative Example 5 is 20%. The sample in Comparative Example 5 was tested by TEM, and the results are as follows: Figure 5 As shown, it can be seen that the Al 2 O 3 The grain size of the layer is significantly increased and the crystallization trend is more obvious, which may be the reason why the oxidation resistance of comparative example 5 is poor.

[0075] Comparative Example 6

[0076] The first Al layer was deposited on the CuAl layer by magnetron sputtering. 2-x G x O 3 layer, wherein the sputtering target is Al 2-x G x O 3 Target material, wherein x=0.2, and other process parameters refer to Example 1. The tensile strength change ratio of the sample of Comparative Example 6 is 10%.

[0077] Comparative Example 7

[0078] Magnetron sputtering was used to deposit Al 2-y Sm y O 3 The second Al layer is deposited on 2-z G z O 3 layer, wherein the sputtering target is Al 2- z G z O 3 Target material, wherein z=0.08, and other process parameters refer to Example 1. The tensile strength change ratio of the sample of Comparative Example 7 is 14%.

[0079] Comparative Example 8

[0080] The first Al layer was deposited on the CuAl layer by magnetron sputtering. 2-x G x O 3 layer, wherein the sputtering target is Al 2-x G x O 3The target material, sputtering power is 200W, sputtering voltage is 400V, and magnetron sputtering method is used on the first Al 2-x G x O 3 Al is deposited on the layer 2- y Sm y O 3 The sputtering power is 200 W, the sputtering voltage is 400 V, and other process parameters refer to Example 1. The film layer of Comparative Example 8 has obvious cracks.

[0081] It should be understood that the above specific embodiments of the present invention are only used to illustrate or explain the principles of the present invention, and do not constitute a limitation of the present invention. Therefore, any modifications, equivalent substitutions, improvements, etc. made without departing from the spirit and scope of the present invention should be included in the protection scope of the present invention. In addition, the appended claims of the present invention are intended to cover all changes and modifications that fall within the scope and boundaries of the appended claims, or the equivalent forms of such scope and boundaries.

Claims

1. A composite insulating material for a cabinet-type current transformer, wherein: The composite insulating material comprises: substrate; a Cu layer on the substrate; a CuAl layer on the Cu layer; The first Al on the CuAl layer 2-x G x O3 layer; In the first Al 2-x G x Al on O3 layer 2-y Sm y O3 layer; In the Al 2-y Sm y The second Al on the O3 layer 2-z G z O3 layer; and In the second Al 2-z G z Al2O3 layer on O3 layer.

2. The composite insulating material according to claim 1, wherein: The first Al 2-x G x The O3 layer is formed on the CuAl layer by the following method: The first Al layer is deposited on the CuAl layer by magnetron sputtering. 2-x G x O3 layer, where the sputtering target is Al 2- x G x O3 target material, wherein x=0.05-0.1, wherein the power source type is RF power source, the sputtering power is 50-100W, the sputtering voltage is 200-300V, the argon gas flow rate is 20-30sccm, and the sputtering temperature is 80-100℃.

3. The composite insulating material according to claim 1, wherein: The Al 2-y Sm y The O3 layer is formed on the first Al 2-x G x On the O3 layer: The first Al 2-x G x The Al 2-y Sm y O3 layer, where the sputtering target is Al 2-y Sm y O3 target material, wherein y=0.02-0.04, wherein the power source type is RF power source, the sputtering power is 60-120W, the sputtering voltage is 200-300V, the argon gas flow rate is 20-30sccm, and the sputtering temperature is 80-100℃.

4. The composite insulating material according to claim 1, wherein: The second Al 2-z G z The O3 layer is formed on the Al 2-y Sm y On the O3 layer: The Al 2-y Sm y The second Al 2-z G z O3 layer, where the sputtering target is Al 2-z G z O3 target, where z=0.12-0.16, where the power type is RF power, the sputtering power is 60-120W, the sputtering voltage is 350-500V, the argon flow rate is 20-30sccm, and the sputtering temperature is 80-100℃.

5. The composite insulating material according to claim 1, wherein: The Al2O3 layer is formed on the second Al 2-z G z On the O3 layer: The second Al 2-z G z The Al2O3 layer is deposited on the O3 layer, wherein the sputtering target is an Al2O3 target, wherein the power type is a radio frequency power supply, the sputtering power is 50-100W, the sputtering voltage is 200-300V, the argon gas flow rate is 20-30sccm, and the sputtering temperature is 130-150°C.

6. The composite insulating material according to claim 1, wherein: The first Al 2-x G x The thickness of the O3 layer is 20-30nm. 2-y Sm y The thickness of the O3 layer is 20-30nm, and the second Al 2-z G z The thickness of the O3 layer is 30-40 nm, and the thickness of the Al2O3 layer is 200-300 nm.

7. A method for preparing a composite insulating material for a cabinet current transformer, comprising: forming a Cu layer on a substrate; forming a CuAl layer on the Cu layer; A first Al layer is formed on the CuAl layer. 2-x G x O3 layer; In the first Al 2-x G x Al is formed on the O3 layer 2-y Sm y O3 layer; In the Al 2-y Sm y The second Al 2-z G z O3 layer; and In the second Al 2-z G z An Al2O3 layer is formed on the O3 layer.

8. The method according to claim 7, wherein: A first Al layer is formed on the CuAl layer. 2-x G x The O3 layer includes: The first Al layer is deposited on the CuAl layer by magnetron sputtering. 2-x G x O3 layer, where the sputtering target is Al 2- x G x O3 target material, wherein x=0.05-0.1, wherein the power source type is RF power source, the sputtering power is 50-100W, the sputtering voltage is 200-300V, the argon gas flow rate is 20-30sccm, and the sputtering temperature is 80-100℃.

9. The method according to claim 7, wherein: In the first Al 2-x G x Al is formed on the O3 layer 2-y Sm y The O3 layer includes: The first Al 2-x G x The Al 2-y Sm y O3 layer, where the sputtering target is Al 2-y Sm y O3 target material, wherein y=0.02-0.04, wherein the power source type is RF power source, the sputtering power is 60-120W, the sputtering voltage is 200-300V, the argon gas flow rate is 20-30sccm, and the sputtering temperature is 80-100℃.

10. The method according to claim 7, wherein: In the Al 2-y Sm y The second Al 2-z G z The O3 layer includes: The Al 2-y Sm y The second Al 2-z G z O3 layer, where the sputtering target is Al 2-z G z O3 target, where z=0.12-0.16, where the power type is RF power, the sputtering power is 60-120W, the sputtering voltage is 350-500V, the argon flow rate is 20-30sccm, and the sputtering temperature is 80-100℃.

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