Rare earth target material binding glue and binding method thereof

Abstract

The invention relates to the technical field of conductive adhesives, and provides a rare earth target binding adhesive and a rare earth target binding method. The rare earth target material binding glue comprises first binding glue and second binding glue, and the first binding glue comprises 10-30 parts of first resin, 50-80 parts of rare earth metal coated copper powder, 1-10 parts of a first electric conduction and heat conduction additive, 1-5 parts of a first interface modifier and 2.5-9 parts of a first auxiliary agent; the second binding glue comprises 30-60 parts of second resin, 25-50 parts of copper-coated rare earth metal powder, 1-10 parts of a second electric conduction and heat conduction additive, 1-5 parts of a second interface modifier and 2.5-9 parts of a second auxiliary agent. The first binding glue is used for being coated on the inner surface of the rare earth target material tube, the second binding glue is used for being coated on the outer surface of the copper back tube, the rare earth metal coated copper powder and the copper coated rare earth metal powder are high in binding strength, good in electric conduction and heat conduction performance and high in high-temperature-resistant strength, the difference of thermal expansion coefficients can be reduced through the rare earth metal coated copper powder and the copper coated rare earth metal powder, and target material deformation is prevented.

Description

[0001] Priority declaration

[0002] This application claims the priority of the Chinese patent application filed with the China Patent Office on September 26, 2024, with application number 202411352509.2 and application name “A rare earth target binding glue and binding method thereof”, the entire contents of which are incorporated by reference in this application. Technical Field

[0003] The present application belongs to the technical field of conductive adhesives, and in particular, relates to a rare earth target material binding adhesive and a binding method thereof. Background Art

[0004] At present, the binding methods of rare earth targets mainly include indium binding and binding glue binding. Among them, indium binding has the widest application range, but indium metal is expensive, and this binding method leads to excessively high cost of rare earth targets; and during the binding process, indium liquid leaks from the edge of the rare earth target, which easily causes the binding rate to be too low; in addition, there are problems such as insufficient indium binding strength and insufficient high temperature resistance. The existing binding glues mainly include conductive silver glue, silver-coated copper glue, graphite glue, etc. However, conductive silver glue and silver-coated copper glue are prone to silver migration at high temperatures, resulting in poor conductivity of the binding glue; graphite glue uses graphite as a conductive additive, and its structural characteristics are limited in graphite glue, resulting in poor conductivity; in addition, the resins in these binding glues are mainly silicone resins or epoxy resins, which have poor long-term high temperature resistance.

[0005] Therefore, it is of great significance to develop a rare earth target binding glue with high binding strength, good electrical and thermal conductivity, and high high temperature resistance. Summary of the invention

[0006] The purpose of the present application is to provide a rare earth target material binding glue and a binding method thereof, aiming to solve the problems of insufficient high temperature resistance, insufficient binding strength and poor electrical and thermal conductivity of the existing rare earth target material binding method.

[0007] In order to achieve the above application purpose, the technical solution adopted in this application is as follows:

[0008] In a first aspect, the present application provides a rare earth target material binding glue, including a first binding glue and a second binding glue, wherein the first binding glue and the second binding glue are measured in independent parts by weight, respectively.

[0009] The first binding glue comprises the following components: 10 to 30 parts of a first resin, 50 to 80 parts of rare earth metal-coated copper powder, 1 to 10 parts of a first conductive and thermal conductive additive, 1 to 5 parts of a first interface modifier, and 2.5 to 9 parts of a first auxiliary agent;

[0010] The second binding glue includes the following components: 30-60 parts of a second resin, 25-50 parts of copper-coated rare earth metal powder, 1-10 parts of a second conductive and thermal conductive additive, 1-5 parts of a second interface modifier and 2.5-9 parts of a second auxiliary agent.

[0011] In a second aspect, the present application provides a rare earth target binding method, comprising the following steps:

[0012] Provide the rare earth target material binding glue of the present application, as well as the copper backing tube and the rare earth target material tube;

[0013] Uniformly coating the first binding glue on the inner surface of the rare earth target tube to form a first glue layer;

[0014] Evenly coating the second binding adhesive on the outer surface of the copper back tube to form a second adhesive layer;

[0015] The rare earth target tube is sleeved outside the copper back tube, and rotated to make the first adhesive layer and the second adhesive layer bonded, and then left to stand and solidify to obtain a rare earth target;

[0016] Wherein, the thickness of the first adhesive layer is 1-10 μm, and the thickness of the second adhesive layer is 1-3 mm.

[0017] Compared with the prior art, this application has the following beneficial effects:

[0018] The first aspect of the present application provides a rare earth target material binding glue, wherein the first binding glue is used to coat the inner surface of the rare earth target material tube, and the rare earth metal-coated copper powder contained therein is used as a conductive and thermally conductive filler to provide basic electrical and thermal conductivity properties, while reducing the difference in thermal expansion coefficient between the rare earth target material tube and the binding glue, effectively preventing deformation of the target material tube, the first conductive and thermally conductive additive can enhance the electrical and thermal conductivity, stabilize heat transfer, and prevent local overheating from damaging the target material, the first interface modifier can corrode the inner surface of the rare earth target material tube to roughen the surface, facilitating the penetration of the first binding glue, thereby enhancing the bonding force between the target material tube and the binding glue and improving the binding strength; the second binding glue contained therein is used to coat the outer surface of the copper back tube, and the copper-coated rare earth metal powder contained therein is used as a conductive and thermally conductive filler to provide basic electrical and thermal conductivity properties, while reducing the difference in thermal expansion coefficient between the rare earth target material tube and the binding glue, effectively preventing deformation of the target material tube, the first conductive and thermally conductive additive can enhance the electrical and thermal conductivity, stabilize heat transfer, and prevent local overheating from damaging the target material, the first interface modifier can corrode the inner surface of the rare earth target material tube to roughen the surface, thereby facilitating the penetration of the first binding glue, thereby enhancing the bonding force between the target material tube and the binding glue and improving the binding strength; the second binding glue contained therein is used to coat the outer surface of the copper back tube, and the copper-coated rare earth metal powder contained therein is used as a conductive and thermally conductive filler to provide basic electrical and thermal conductivity properties, while reducing the difference in thermal expansion coefficient between the rare earth target material tube and the binding glue, The difference in thermal expansion coefficient between the first and second binding adhesives can effectively prevent the copper back tube from deforming. The second conductive and thermal conductive additive can enhance the electrical and thermal conductivity, stabilize heat transfer, and prevent local overheating from damaging the target material. The second interface modifier can corrode the outer surface of the copper back tube to roughen the surface, making it easier for the second binding adhesive to penetrate, thereby further enhancing the bonding force between the copper back tube and the binding adhesive and improving the binding strength. Therefore, the first binding adhesive and the second binding adhesive of the present application can reduce the difference in thermal expansion coefficient and prevent the target material from deforming. On the other hand, the defects and holes at the interface between the first binding adhesive layer and the rare earth target tube, the first binding adhesive layer and the second binding adhesive layer, and the copper back tube and the second binding adhesive layer are significantly reduced, which increases the conductive contact points and reduces the thermal conductivity barriers, thereby achieving stronger binding strength, better electrical and thermal conductivity, and higher high temperature resistance.

[0019] The second aspect of the present application provides a rare earth target material binding method, wherein a first binding glue containing rare earth metal-coated copper powder is uniformly coated on the inner surface of the rare earth target material tube, and a second binding glue containing copper-coated rare earth metal powder is uniformly coated on the outer surface of the copper back tube, and then the rare earth target material tube is sleeved outside the copper back tube, which can not only realize the bonding of the copper back tube and the rare earth target material tube to form a target material, but also reduce the difference in thermal expansion coefficient and prevent deformation of the target material. In addition, the binding method has a simple process, is easy to operate, has a low cost, and has high binding strength, good electrical and thermal conductivity, and high high temperature resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0021] Figure 1 This is a SEM image of the first binding glue after curing in the rare earth target binding glue provided in Example 1 of the present application; DETAILED DESCRIPTION

[0022] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0023] In a first aspect, an embodiment of the present application provides a rare earth target material binding glue, including a first binding glue and a second binding glue, wherein the first binding glue and the second binding glue are measured in independent parts by weight, respectively.

[0024] The first binding glue comprises the following components: 10 to 30 parts of a first resin, 50 to 80 parts of rare earth metal-coated copper powder, 1 to 10 parts of a first conductive and thermal conductive additive, 1 to 5 parts of a first interface modifier, and 2.5 to 9 parts of a first auxiliary agent;

[0025] The second binding glue includes the following components: 30-60 parts of a second resin, 25-50 parts of copper-coated rare earth metal powder, 1-10 parts of a second conductive and thermal conductive additive, 1-5 parts of a second interface modifier and 2.5-9 parts of a second auxiliary agent.

[0026] The rare earth target material binding glue provided in the embodiment of the present application comprises a first binding glue used for coating on the inner surface of the rare earth target material tube, and the rare earth metal-coated copper powder contained therein is used as a conductive and thermally conductive filler to provide basic properties of conductivity and thermal conductivity, and at the same time can reduce the difference in thermal expansion coefficient between the rare earth target material tube and the binding glue, and effectively prevent the target material tube from deformation, the first conductive and thermally conductive additive can enhance the conductivity and thermal conductivity, stabilize heat transfer, and prevent local overheating from damaging the target material, the first interface modifier can corrode the inner surface of the rare earth target material tube to roughen the surface, and facilitate the penetration of the first binding glue, thereby enhancing the bonding force between the target material tube and the binding glue and improving the binding strength; the second binding glue contained therein is used for coating on the outer surface of the copper back tube, and the copper-coated rare earth metal powder contained therein is used as a conductive and thermally conductive filler to provide basic properties of conductivity and thermal conductivity, and at the same time can reduce the difference in thermal expansion coefficient between the rare earth target material tube and the binding glue, and at the same time can reduce the difference in thermal expansion coefficient between the rare earth target material tube and the binding glue, and at the same time can reduce the difference in thermal expansion coefficient between the rare earth target material tube and the binding glue, and at the same time can reduce the difference between the ... The difference in thermal expansion coefficient between the first and second binding adhesives can effectively prevent the copper back tube from deforming. The second conductive and thermally conductive additive can enhance the electrical and thermal conductivity, stabilize heat transfer, and prevent local overheating from damaging the target material. The second interface modifier can corrode the outer surface of the copper back tube to roughen the surface, making it easier for the second binding adhesive to penetrate, thereby further enhancing the bonding force between the copper back tube and the binding adhesive and improving the binding strength. Therefore, the first binding adhesive and the second binding adhesive of the present application can reduce the difference in thermal expansion coefficient and prevent deformation of the target material on the one hand, and significantly reduce the defects and holes at the interface between the first binding adhesive layer and the rare earth target tube, the first binding adhesive layer and the second binding adhesive layer, and the copper back tube and the second binding adhesive layer on the other hand, increase the conductive contact points and reduce thermal conductivity barriers, and therefore have stronger binding strength, better electrical and thermal conductivity, and higher high temperature resistance.

[0027] First binding glue:

[0028] In an embodiment, the particle size of the rare earth metal-coated copper powder is 20-50 μm, for example, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, 50 μm, etc.

[0029] In an embodiment, the copper content of the rare earth metal coated copper powder is 60-80wt%, such as 60wt%, 65wt%, 70wt%, 75wt%, 80wt%, etc. Within this copper content range, the thermal expansion coefficient between the rare earth target tube and the binding glue is small.

[0030] In an embodiment, the rare earth metal-coated copper powder is selected from at least one of dysprosium-coated copper powder, terbium-coated copper powder, and dysprosium-terbium-coated copper powder. Adding these rare earth metal-coated copper powders as the main filler provides basic electrical and thermal properties, and enables the binding glue to achieve a uniform transition between the rare earth target tube and the copper backing tube, thereby achieving better electrical and thermal conductivity.

[0031] In an embodiment, the first interface modifier includes a silane coupling agent (KH550), phosphoric acid, zinc oxide and nitrite in a mass ratio of (2-5) / (1-3) / (1-2) / (0.5-1); wherein the nitrite may be sodium nitrite. Phosphoric acid, zinc oxide and nitrite can phosphate the inner surface of the rare earth target tube, and form a zinc phosphate complex affinity layer connecting the rare earth metal target tube and the binding glue on the surface of the rare earth metal target tube, thereby achieving the effect of enhancing bonding through chemical forces; at the same time, the silane coupling agent can react with the surface of the rare earth target tube to form a dense passivation film with a spatial network structure, and can also react with the binding glue coating to form a network interpenetrating structure, thereby significantly improving the bonding performance of the binding glue coating on the surface of the rare earth target tube.

[0032] In an embodiment, the first conductive and thermally conductive additive includes acetylene black, Al2O3, ZnO and MgO in a mass ratio of (0.5-2) / (1-3) / (1-5) / (1-8); under the interaction of these specific contents of conductive and thermally conductive additives, the electrical and thermal conductivity can be enhanced, the heat transfer can be stabilized, and local overheating can be prevented from causing damage to the rare earth target tube.

[0033] In an embodiment, the first resin includes a silicone resin modified by a polyimide resin and an epoxy resin in a mass ratio of (3-5) / (1-2); wherein the step of preparing the silicone resin modified by a polyimide resin includes: adding the polyimide resin to the silicone resin according to the mass ratio of the polyimide resin to the silicone resin (1-5) / (95-99), stirring at high speed, and centrifuging to obtain the silicone resin modified by a polyimide resin. Using the silicone resin as the base resin to form a resin of a conductive elastomer can relieve the stress between the interface of the rare earth target tube and the copper back tube, so that the rare earth target tube will not be off-target during thermal expansion, and adding a small amount of polyimide resin to modify the silicone resin can enhance the binding strength and improve the ultra-high temperature stability, so that the binding glue can be used for a long time in a high temperature environment. The epoxy resin is selected from any one or more combinations of bisphenol A epoxy resin, bisphenol F epoxy resin, hydrogenated bisphenol A epoxy resin, hydrogenated bisphenol F epoxy resin, alicyclic epoxy resin and bisphenol A diglycidyl ether.

[0034] In the embodiment, the first auxiliary agent includes 2 to 6 parts of a curing agent and 0.5 to 3 parts of an antioxidant. The curing agent includes dicyandiamide, latent modified imidazole, and liquid aluminum dihydrogen phosphate in a mass ratio of (0.6 to 2) / (0.4 to 1) / (1 to 3); dicyandiamide and latent modified imidazole have a certain latency and can be slowly cured at room temperature, so there is no need for heating and curing, which can reduce energy consumption and simplify the process; liquid aluminum dihydrogen phosphate can react with the oxide on the surface of the rare earth metal-coated copper powder at room temperature to generate insoluble phosphates, thereby forming a dense and solid phosphate protective layer, and the resin can also seal it, which plays a role in enhancing high temperature resistance and corrosion resistance; the antioxidant is selected from at least one of sodium phosphite, potassium phosphite, and ammonium phosphite.

[0035] In an embodiment, the viscosity of the first binding glue is 8000-15000 cps.

[0036] The preparation method of the above-mentioned first binding glue specifically includes the following steps: weighing 10-30 parts of the first resin, 50-80 parts of rare earth metal-coated copper powder, 1-10 parts of the first conductive and thermally conductive additive, 1-5 parts of the first interface modifier, 2-6 parts of the curing agent and 0.5-3 parts of the antioxidant; adding the curing agent, the first interface modifier, the first conductive and thermally conductive additive and the rare earth metal-coated copper powder to the first resin in sequence and stirring, then slurrying, and then adding the antioxidant and stirring evenly to obtain the first binding glue. Among them, the specific materials and contents of the first resin, the rare earth metal-coated copper powder, the first conductive and thermally conductive additive, the first interface modifier, the curing agent and the antioxidant are as described above and will not be repeated here.

[0037] In an embodiment, the steps of preparing rare earth metal coated copper powder include: dissolving a rare earth metal source in a solvent, then adding copper powder and a reducing agent for reduction reaction, and then filtering, purifying, and drying to obtain rare earth metal coated copper powder. The rare earth metal source is selected from at least one of terbium nitrate, terbium chloride, dysprosium nitrate, and dysprosium chloride; the solvent is selected from deionized water; the reducing agent is selected from sodium borohydride; the pH value of the reduction reaction is 9 to 11, the temperature is 40 to 70°C, and the time is 0.5 to 3 hours. The reaction conditions are helpful to accelerate the deposition of rare earth metals and obtain a uniform rare earth metal coating layer.

[0038] Specifically, the rare earth metal source is dissolved in deionized water to prepare a rare earth metal source solution of the required concentration. The concentration can be adjusted according to actual needs, generally between 0.01M and 0.1M; copper powder is added to the rare earth metal salt solution, and it is necessary to ensure that the solution completely immerses the copper powder. Sodium hydroxide or ammonia water can be used to adjust the pH value of the reduction reaction solution. In order to ensure the uniformity of rare earth metal deposition, a magnetic stirrer can be used to slightly stir the reaction solution during the reduction reaction. Purification can be done by thoroughly rinsing with deionized water to remove unreacted rare earth metal sources on the surface. Drying can be done by blowing the powder surface dry with nitrogen or drying at low temperature.

[0039] In an embodiment, before adding the copper powder to the rare earth metal source solution, the method further includes: briefly treating the copper powder in dilute hydrochloric acid or dilute nitric acid to remove the oxide layer on the surface, and then thoroughly rinsing with deionized water. This step helps to expose the clean copper surface and promote the subsequent terbium deposition.

[0040] In an embodiment, after the drying step, the process further comprises: heating the rare earth metal coated copper powder to 200-300° C. in an inert atmosphere or a reducing atmosphere for 1-2 hours. The adhesion and uniformity of the rare earth metal layer can be enhanced by subsequent heat treatment of the rare earth metal coated copper powder.

[0041] Second binding glue:

[0042] In an embodiment, the particle size of the copper-coated rare earth metal powder is 0.1 to 5 μm, such as 0.1 μm, 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, etc.;

[0043] In an embodiment, the rare earth metal content in the copper-coated rare earth metal powder is 50-70wt%, for example 50wt%, 55wt%, 60wt%, 65wt%, 70wt%, etc.; within this rare earth metal content range, the thermal expansion coefficient between the copper back tube and the binding glue is small.

[0044] In an embodiment, the copper-coated rare earth metal powder is selected from at least one of copper-coated dysprosium powder, copper-coated terbium powder, and copper-coated dysprosium-terbium powder. Adding these copper-coated rare earth metal powders as the main filler provides basic electrical and thermal properties, and enables the binding glue to achieve a uniform transition between the copper backing tube and the rare earth target tube, thereby achieving better electrical and thermal conductivity.

[0045] In an embodiment, the second interface modifier includes a silane coupling agent, phosphoric acid, zinc oxide and nitrite in a mass ratio of (2-5) / (1-3) / (1-2) / (0.5-1); phosphoric acid, zinc oxide and nitrite can phosphate the inner surface of the copper back tube, and form a zinc phosphate complex affinity layer connecting the copper back tube and the rubber on the surface of the copper back tube, thereby achieving the effect of enhancing adhesion through chemical force; at the same time, the silane coupling agent can react with the surface of the copper back tube to form a dense passivation film with a spatial network structure, and can also react with the binding glue coating to form a network interpenetrating structure, thereby significantly improving the bonding performance of the binding glue coating on the surface of the copper back tube.

[0046] In an embodiment, the second conductive and thermally conductive additive includes acetylene black, Al2O3, ZnO and MgO in a mass ratio of (0.5-2) / (1-3) / (1-5) / (1-8); under the interaction of these specific contents of conductive and thermally conductive additives, the electrical and thermal conductivity can be enhanced, the heat transfer can be stabilized, and local overheating can be prevented from causing damage to the rare earth target tube.

[0047] In an embodiment, the second resin includes a silicone resin modified by a polyimide resin and an epoxy resin in a mass ratio of (3-5) / (1-2); wherein the step of preparing the silicone resin modified by a polyimide resin includes: adding the polyimide resin to the silicone resin in a mass ratio of (1-5) / (95-99) and stirring at high speed, and centrifugally degassing to obtain the silicone resin modified by a polyimide resin. Using silicone resin as a base resin to form a resin of a conductive elastomer can relieve the stress between the interface of the rare earth target tube and the copper back tube, so that the rare earth target tube will not be off-target during thermal expansion, and adding a small amount of polyimide resin to modify the silicone resin can enhance the binding strength and improve the ultra-high temperature stability, so that the binding glue can be used for a long time in a high temperature environment. The epoxy resin is selected from any one or more combinations of bisphenol A epoxy resin, bisphenol F epoxy resin, hydrogenated bisphenol A epoxy resin, hydrogenated bisphenol F epoxy resin, alicyclic epoxy resin and bisphenol A diglycidyl ether.

[0048] In the embodiment, the second auxiliary agent includes 2 to 6 parts of a curing agent and 0.5 to 3 parts of an antioxidant; wherein the curing agent includes dicyandiamide, latent modified imidazole, and liquid aluminum dihydrogen phosphate in a mass ratio of (0.6 to 2) / (0.4 to 1) / (1 to 3); dicyandiamide and latent modified imidazole have a certain latency and can be slowly cured at room temperature, so there is no need for heating and curing, which can reduce energy consumption and simplify the process flow; liquid aluminum dihydrogen phosphate can react with oxides on the surface of copper-coated rare earth metal powder at room temperature to generate insoluble phosphates, thereby forming a dense and solid phosphate protective layer, and the resin can also seal it, thereby enhancing high temperature resistance and corrosion resistance; the antioxidant is selected from at least one of sodium phosphite, potassium phosphite, and ammonium phosphite;

[0049] In an embodiment, the viscosity of the second binding glue is 800-10000 cps, and this viscosity range is conducive to uniform coating of the first binding glue and achieving thinner coating.

[0050] The preparation method of the above-mentioned second binding glue specifically includes the following steps: weighing 30-60 parts of a second resin, 25-50 parts of copper-coated rare earth metal powder, 1-10 parts of a second conductive and thermally conductive additive, 1-5 parts of a second interface modifier, 2-6 parts of a curing agent and 0.5-3 parts of an antioxidant; adding the curing agent, the second interface modifier, the second conductive and thermally conductive additive and the copper-coated rare earth metal powder to the second resin in sequence and stirring them, then slurrying, and then adding an antioxidant and stirring evenly to obtain a second binding glue; wherein the specific materials and contents of the second resin, copper-coated rare earth metal powder, the second conductive and thermally conductive additive, the second interface modifier, the curing agent and the antioxidant are as described above and will not be repeated here.

[0051] In the embodiment, the step of preparing the copper-coated rare earth metal powder includes: dissolving the copper source in a solvent, then adding the rare earth metal powder, performing a replacement reaction, and then filtering, purifying, and drying to obtain the copper-coated rare earth metal powder. The filtrate of this embodiment is a rare earth metal salt solution, which can be used as a raw material for preparing the rare earth metal-coated copper powder in the embodiment of the present application, that is, it can be used instead of the rare earth metal source solution, so the raw material cost can be reduced.

[0052] In the embodiment, the pH value of the replacement reaction is 4 to 7, the temperature is 50 to 80° C., and the time is 1 to 4 hours;

[0053] In an embodiment, after the drying step, the method further comprises: heating the copper-coated rare earth metal powder to 200-300° C. in an inert atmosphere or a reducing atmosphere for 1-2 hours. The subsequent heat treatment of the copper-coated rare earth metal powder can enhance the adhesion and uniformity of the rare earth metal layer.

[0054] A second aspect of an embodiment of the present application provides a rare earth target binding method, comprising the following steps:

[0055] S01: providing the rare earth target material binding glue, copper backing tube, and rare earth target material tube according to the embodiment of the present application;

[0056] S02: uniformly coating the first binding glue on the inner surface of the rare earth target tube to form a first glue layer;

[0057] S03: evenly coating the second binding adhesive on the outer surface of the copper back tube to form a second adhesive layer;

[0058] S04: putting a rare earth target tube on the outside of the copper back tube, and bonding the first adhesive layer and the second adhesive layer, and then standing and curing to obtain a rare earth target;

[0059] The thickness of the first adhesive layer is 1-10 μm, and the thickness of the second adhesive layer is 1-3 mm.

[0060] The rare earth target material binding method provided in the embodiment of the present application is to uniformly coat the inner surface of the rare earth target material tube with a first binding glue containing rare earth metal-coated copper powder, and uniformly coat the outer surface of the copper backing tube with a second binding glue containing copper-coated rare earth metal powder, and then sleeve the rare earth target material tube outside the copper backing tube, which can not only realize the bonding of the copper backing tube and the rare earth target material tube to form a target material, but also reduce the difference in thermal expansion coefficient and prevent deformation of the target material. In addition, the binding method is simple in process, easy to operate, low in cost, and has high binding strength, good electrical and thermal conductivity, and high high temperature resistance.

[0061] In an embodiment, the rare earth target tube may be a terbium target tube, a dysprosium target tube, or an alloy target tube containing dysprosium and / or terbium.

[0062] The following describes the invention in conjunction with specific embodiments.

[0063] Rare earth target material binding glue example:

[0064] Example 1

[0065] This embodiment provides a rare earth target material binding glue, including a first binding glue and a second binding glue, the first binding glue and the second binding glue are respectively calculated in independent parts by weight.

[0066] The first binding glue includes 16 parts of polyimide resin modified silicone resin, 4 parts of bisphenol A epoxy resin, 65 parts of terbium copper powder, 7 parts of a first conductive and thermally conductive additive, 3 parts of a first interface modifier, 5 parts of a curing agent and 2 parts of an antioxidant; wherein the first conductive and thermally conductive additive is composed of acetylene black, Al2O3, ZnO and MgO in a mass ratio of 1 / 2 / 3 / 5, the first interface modifier is composed of KH550, phosphoric acid, zinc oxide and sodium nitrite in a mass ratio of 4.5 / 2.5 / 1.5 / 0.8, the curing agent is composed of dicyandiamide, latent modified imidazole and liquid aluminum dihydrogen phosphate in a mass ratio of 1.5 / 0.8 / 2, the antioxidant is sodium phosphite, the D50 particle size of the terbium copper powder is 3.2μm, the copper content in the terbium copper powder is 71wt%, and the viscosity of the first binding glue is 11500cps;

[0067] The second binding glue includes 36 parts of polyimide resin modified silicone resin, 9 parts of bisphenol A epoxy resin, 38 parts of copper-coated terbium powder, 7 parts of a second conductive and thermally conductive additive, 3 parts of a second interface modifier, 5 parts of a curing agent and 2 parts of an antioxidant; wherein the second conductive and thermally conductive additive is composed of acetylene black, Al2O3, ZnO and MgO in a mass ratio of 1 / 2 / 3 / 5, the second interface modifier is composed of KH550, phosphoric acid, zinc oxide and sodium nitrite in a mass ratio of 4.5 / 2.5 / 1.5 / 0.8, the curing agent is composed of dicyandiamide, latent modified imidazole and liquid aluminum dihydrogen phosphate in a mass ratio of 1.5 / 0.8 / 2, the antioxidant is sodium phosphite, the D50 particle size of the copper-coated terbium powder is 2.8μm, the terbium content in the copper-coated terbium powder is 61wt%, and the viscosity of the second binding glue is 8300cps;

[0068] The steps for preparing the first binding glue and the second binding glue are as follows:

[0069] Preparation of polyimide resin modified silicone resin: according to the mass ratio of polyimide resin to silicone resin being 3 / 97, adding polyimide resin into silicone resin and stirring at high speed, and then centrifugally degassing to obtain polyimide resin modified silicone resin;

[0070] Preparation of terbium-coated copper powder: dissolving terbium nitrate in deionized water, then adding copper powder and sodium borohydride, heating the reaction system to 55°C, and adjusting the pH value of the reaction system to 10 with sodium hydroxide, stirring for reduction reaction for 2 hours, standing for 1 hour and then filtering, washing the filter residue with deionized water, and then drying with nitrogen, and finally heating to 250°C in an argon-hydrogen mixed atmosphere and keeping the temperature for 1.5 hours to obtain terbium-coated copper powder;

[0071] Preparation of copper-coated terbium powder: dissolve copper nitrate in deionized water, then add terbium powder, heat the reaction system to 60°C, control the pH value of the reaction system to 5.5, stir to carry out replacement reaction for 2 hours, let stand for 1 hour and then filter, rinse the filter residue with deionized water, then blow dry with nitrogen, and finally heat to 250°C in an argon-hydrogen mixed atmosphere and keep warm for 1.5 hours to obtain copper-coated terbium powder;

[0072] Weigh each component according to the first binding adhesive formula of this embodiment; then sequentially add a curing agent, a first interface modifier, a first conductive and thermally conductive additive, and terbium-coated copper powder to a polyimide resin-modified silicone resin and stir evenly, then add bisphenol A epoxy resin and mix evenly, centrifuge and degas to obtain a primary slurry; then perform three-roll pulping on the primary slurry, then add an antioxidant and stir evenly to obtain a first binding adhesive;

[0073] According to the second binding adhesive formula of this embodiment, each component is weighed; then the curing agent, the second interface modifier, the second conductive and thermal conductive additive and the copper-coated terbium powder are sequentially added to the polyimide resin-modified silicone resin and stirred evenly, then the bisphenol A epoxy resin is added and mixed evenly, and centrifugal degassing is performed to obtain a primary slurry; then the primary slurry is subjected to three-roll slurrying, and then an antioxidant is added and stirred evenly to obtain a second binding adhesive.

[0074] Example 2

[0075] This embodiment provides a rare earth target material binding glue, which is different from the embodiment 1 in that:

[0076] The first binding glue contains 8 parts of polyimide resin-modified silicone resin, 2 parts of bisphenol A epoxy resin, and 80 parts of terbium-coated copper powder. The viscosity of the first binding glue is 14500 cps.

[0077] The second binding adhesive contains 24 parts of polyimide resin-modified silicone resin, 6 parts of bisphenol A epoxy resin, and 50 parts of copper-coated terbium powder. The viscosity of the second binding adhesive is 9800 cps.

[0078] Example 3

[0079] This embodiment provides a rare earth target material binding glue, which is different from the embodiment 1 in that:

[0080] The first binding glue contains 24 parts of polyimide resin-modified silicone resin, 6 parts of bisphenol A epoxy resin, and 50 parts of terbium-coated copper powder. The viscosity of the first binding glue is 9800 cps.

[0081] The second binding adhesive contains 48 parts of polyimide resin-modified silicone resin, 12 parts of bisphenol A epoxy resin, and 25 parts of copper-coated terbium powder. The viscosity of the second binding adhesive is 1300 cps.

[0082] Example 4

[0083] This embodiment provides a rare earth target material binding glue, which is different from the embodiment 1 in that:

[0084] In the first binding glue, the copper content of the terbium-coated copper powder is 61wt%; in the second binding glue, the terbium content of the copper-coated terbium powder is 52wt%;

[0085] To prepare terbium-coated copper powder, the reduction reaction is carried out for 2.5 hours; to prepare copper-coated terbium powder, the replacement reaction is carried out for 3.5 hours.

[0086] Example 5

[0087] This embodiment provides a rare earth target material binding glue, which is different from the embodiment 1 in that:

[0088] In the first binding glue, the copper content of the terbium-coated copper powder is 78wt%; in the second binding glue, the terbium content of the copper-coated terbium powder is 69wt%;

[0089] To prepare terbium-coated copper powder, the reduction reaction is carried out for 1 hour; to prepare copper-coated terbium powder, the replacement reaction is carried out for 1 hour.

[0090] Example 6

[0091] This embodiment provides a rare earth target material binding glue, which is different from the embodiment 1 in that:

[0092] In the first binding glue, dysprosium-coated copper powder is used to replace terbium-coated copper powder; in the second binding glue, copper-coated dysprosium powder is used to replace copper-coated terbium powder;

[0093] To prepare dysprosium-coated copper powder, dysprosium nitrate is used instead of terbium nitrate; to prepare copper-coated dysprosium powder, dysprosium powder is used instead of terbium powder.

[0094] Example 7

[0095] This embodiment provides a rare earth target material binding glue, which is different from the embodiment 1 in that:

[0096] In the first binding glue, the first interface modifier is composed of phosphoric acid, zinc oxide and sodium nitrite in a mass ratio of 2.5 / 1.5 / 0.8; in the second binding glue, the second interface modifier is composed of phosphoric acid, zinc oxide and sodium nitrite in a mass ratio of 2.5 / 1.5 / 0.8.

[0097] Example 8

[0098] This embodiment provides a rare earth target material binding glue, which is different from the embodiment 1 in that:

[0099] In the first binding glue, the first interface modifier is selected from KH550; in the second binding glue, the second interface modifier is selected from KH550.

[0100] Example 9

[0101] This embodiment provides a rare earth target material binding glue, which is different from the embodiment 1 in that:

[0102] In the first binding adhesive and the second binding adhesive, the curing agent is composed of dicyandiamide and latent modified imidazole in a mass ratio of 1.5 / 0.8.

[0103] Example 10

[0104] This embodiment provides a rare earth target material binding glue, which is different from the embodiment 1 in that:

[0105] In both the first binding adhesive and the second binding adhesive, the polyimide resin-modified silicone resin is replaced by silicone resin.

[0106] Comparative Example 1

[0107] This comparative example provides a conductive silver paste, which includes 76 parts of micron silver powder, 24 parts of bisphenol A epoxy resin, 1 part of dicyandiamide (curing agent), 0.1 parts of 1-cyanoethyl-2-ethyl-4-methylimidazole (accelerator), and 1.5 parts of 1,4-butanediol diglycidyl ether (diluent).

[0108] Comparative Example 2

[0109] This comparative example provides a rare earth target material binding glue, which is different from Example 1 in that:

[0110] The rare earth target material binding glue only includes the first binding glue.

[0111] Comparative Example 3

[0112] This comparative example provides a rare earth target material binding glue, which is different from Example 1 in that:

[0113] The rare earth target material binding glue only includes the second binding glue.

[0114] Comparative Example 4

[0115] This comparative example provides a rare earth target material binding glue, which is different from Example 1 in that:

[0116] The first binding glue does not contain a first interface modifier; the second binding glue does not contain a second interface modifier.

[0117] Comparative Example 5

[0118] This comparative example provides a rare earth target material binding glue, which is different from Example 1 in that:

[0119] The first binding glue contains 8 parts of the first resin and 85 parts of the terbium-coated copper powder; the second binding glue contains 25 parts of the second resin and 55 parts of the copper-coated terbium powder.

[0120] Comparative Example 6

[0121] This comparative example provides a rare earth target material binding glue, which is different from Example 1 in that:

[0122] The first binding glue contains 35 parts of the first resin and 45 parts of the terbium-coated copper powder; the second binding glue contains 65 parts of the second resin and 20 parts of the copper-coated terbium powder.

[0123] Related performance test analysis:

[0124] 1. The surface morphology of the first binding glue after curing in the binding glue provided in Example 1 was tested using a scanning electron microscope. The test results are as follows: Figure 1 As shown:

[0125] from Figure 1It can be seen that the terbium-coated copper powder (metal filler) is dendritic, which can increase the contact area in the resin carrier, form an effective and continuous current conduction, and facilitate heat conduction. In addition, the surface of the terbium-coated copper powder is evenly wrapped by conductive and thermal conductive additives, interface modifiers and resins, which can prevent the metal filler from being oxidized at high temperatures, thereby forming a stable binding structure. In addition, from the morphological point of view, the surface roughness is relatively large, which can increase the contact with the target tube interface and improve the binding strength.

[0126] 2. The test samples made of the binding glue provided in Examples 1 to 10 and Comparative Examples 1 to 6 were respectively subjected to room temperature curing time, electrical conductivity, thermal conductivity, and high temperature tensile tests using a Leeb hardness tester (the hardness was tested once every two hours, and when the hardness was greater than 600HL, it was determined to be completely cured), a resistance testing device, a thermal conductivity meter, and a tensile testing machine; specifically, for Examples 1 to 10 and Comparative Examples 4 to 6, the second binding glue was first coated on the substrate surface, and then the first binding glue was coated on the surface of the second binding glue coating; for Comparative Examples 1, 2, and 3, the conductive silver glue, the first binding glue, and the second binding glue were respectively coated on different substrate surfaces; after room temperature curing, 16 test samples with a size of 30 mm×20 mm×3 mm were obtained;

[0127] 3. According to the ASTM D1002 test method, the binding strength test was performed on the binding glue provided in Examples 1 to 10 and Comparative Examples 1 to 6; specifically, for Examples 1 to 10 and Comparative Examples 4 to 6, the first binding glue was coated on the surface of one of the metal bonding test boards, and the second binding glue was coated on the surface of the other metal bonding test board; for Comparative Examples 1, 2, and 3, the conductive silver glue, the first binding glue, and the second binding glue were coated on the surfaces of the two metal bonding test boards, respectively; the two metal bonding test boards were bonded and cured to obtain a test sample;

[0128] The test results (based on Comparative Example 1, the test values ​​are increments relative to Comparative Example 1) are shown in Table 1 below:

[0129] Table 1

[0130]

[0131] It can be seen from Table 1 that the electrical conductivity, thermal conductivity, shear strength and high-temperature tensile force of the binding glue provided in Examples 1 to 10 after curing at room temperature are significantly better than those of Comparative Example 1 (conductive silver glue), and Comparative Example 1 cannot be cured at room temperature and needs to be cured at a higher temperature, indicating that the binding glue provided in the present application can be cured at room temperature, has low energy consumption, simple process, good electrical and thermal conductivity, high binding strength and high high temperature resistance, and can be used instead of conductive silver glue.

[0132] The electrical conductivity, thermal conductivity, shear strength and high-temperature tensile strength of the binding glue provided in Example 1 are significantly better than those in Examples 7, 8 and Comparative Example 4, especially the shear strength and high-temperature tensile strength, indicating that the phosphoric acid, zinc oxide and nitrite in the interface modifier can phosphate the metal surface, forming a zinc phosphate complex affinity layer connecting the metal and the binding glue on the metal surface, thereby enhancing the binding strength; at the same time, the silane coupling agent can react with the metal surface to form a dense passivation film with a spatial network structure, and can also react with the binding glue coating to form a network interpenetrating structure, which is more conducive to the uniform distribution of metal fillers, thereby improving the binding strength, high temperature stability, and electrical and thermal conductivity.

[0133] The room temperature curing time of the binding glue provided in Example 1 is appropriate and significantly shorter than that of Example 9 (which does not contain liquid aluminum dihydrogen phosphate curing agent), indicating that dicyandiamide, latent modified imidazole and liquid aluminum dihydrogen phosphate can play a synergistic role in the curing process and promote resin curing; and the electrical conductivity, thermal conductivity, shear strength and high-temperature tensile force are also significantly better than those in Example 9. This is mainly due to the reaction of liquid aluminum dihydrogen phosphate with the oxide on the surface of terbium-coated copper powder to form an insoluble phosphate protective layer which is sealed by resin, thereby enhancing high temperature resistance and corrosion resistance, thereby forming a stable and effective conductive network.

[0134] The room temperature curing time of the binding glue provided in Example 1 is significantly shorter than that in Example 10 (silicone resin is added), and the electrical conductivity, thermal conductivity, shear strength and high-temperature tensile force are also significantly better than those in Example 10, indicating that the silicone resin modified with polyimide resin has a better curing effect and can shorten the curing time. At the same time, the modification of the silicone resin with polyimide resin can effectively enhance the binding strength and improve the ultra-high temperature stability.

[0135] The electrical conductivity, thermal conductivity, shear strength and high-temperature tensile force of the binding glue provided in Example 1 are significantly better than those of Comparative Examples 2 and 3, indicating that the binding glue of the present application contains the first binding glue and the second binding glue, which can significantly reduce defects and holes at each interface, increase conductive contact points and reduce thermal conductivity barriers, and therefore has better electrical and thermal conductivity and binding strength.

[0136] The electrical conductivity and thermal conductivity of the binding glue provided in Examples 1 to 3 are significantly better than those in Comparative Examples 5 and 6, indicating that the first resin and terbium-coated copper powder are within the scope of the embodiments of the present application, which is more conducive to the uniform distribution of the terbium-coated copper powder in the resin matrix to form a continuous conductive network, thereby having better electrical and thermal conductivity.

[0137] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A rare earth target material binding glue, characterized in that: It includes a first binding glue and a second binding glue, wherein the first binding glue and the second binding glue are measured in independent parts by weight, The first binding glue comprises the following components: 10 to 30 parts of a first resin, 50 to 80 parts of rare earth metal-coated copper powder, 1 to 10 parts of a first conductive and thermal conductive additive, 1 to 5 parts of a first interface modifier, and 2.5 to 9 parts of a first auxiliary agent; The second binding glue includes the following components: 30-60 parts of a second resin, 25-50 parts of copper-coated rare earth metal powder, 1-10 parts of a second conductive and thermal conductive additive, 1-5 parts of a second interface modifier and 2.5-9 parts of a second auxiliary agent.

2. The rare earth target binding glue according to claim 1, characterized in that: The particle size of the rare earth metal coated copper powder is 20 to 50 μm; and / or, the copper content in the rare earth metal-coated copper powder is 60-80wt%; And / or, the rare earth metal coated copper powder is selected from at least one of dysprosium coated copper powder, terbium coated copper powder and dysprosium-terbium coated copper powder.

3. The rare earth target binding glue according to claim 2, characterized in that: The steps of preparing the rare earth metal coated copper powder include: dissolving a rare earth metal source in a solvent, then adding copper powder and a reducing agent to carry out a reduction reaction, and then filtering, purifying and drying to obtain the rare earth metal coated copper powder.

4. The rare earth target binding glue according to claim 3, characterized in that: At least one of the following conditions is met: The rare earth metal source is selected from at least one of terbium nitrate, terbium chloride, dysprosium nitrate and dysprosium chloride; The reducing agent is selected from sodium borohydride; The pH value of the reduction reaction is 9-11, the temperature is 40-70°C, and the time is 0.5-3h; After the drying step, the method further comprises: heating the rare earth metal-coated copper powder to 200-300° C. in an inert atmosphere or a reducing atmosphere for 1-2 hours.

5. The rare earth target binding glue according to claim 1, characterized in that: The particle size of the copper-coated rare earth metal powder is 0.1 to 5 μm; and / or, the rare earth metal content in the copper-coated rare earth metal powder is 50-70wt%; And / or, the copper-coated rare earth metal powder is selected from at least one of copper-coated dysprosium powder, copper-coated terbium powder, and copper-coated dysprosium-terbium powder.

6. The rare earth target binding glue according to claim 5, characterized in that: The steps of preparing the copper-coated rare earth metal powder include: dissolving a copper source in a solvent, then adding the rare earth metal powder, performing a replacement reaction, and then filtering, purifying and drying to obtain the copper-coated rare earth metal powder.

7. The rare earth target binding glue according to claim 6, characterized in that: The pH value of the replacement reaction is 4 to 7, the temperature is 50 to 80° C., and the time is 1 to 4 hours; And / or, after the drying step, the method further comprises: heating the copper-coated rare earth metal powder to 200-300° C. in an inert atmosphere or a reducing atmosphere and keeping the temperature for 1-2 hours.

8. The rare earth target binding glue according to claim 1, characterized in that: At least one of the following conditions is met: The first interface modifier and the second interface modifier each independently include a silane coupling agent, phosphoric acid, zinc oxide and nitrite in a mass ratio of (2-5) / (1-3) / (1-2) / (0.5-1); The first conductive and thermally conductive additive and the second conductive and thermally conductive additive each independently comprise acetylene black, Al2O3, ZnO and MgO in a mass ratio of (0.5-2) / (1-3) / (1-5) / (1-8); The first resin and the second resin each independently include a polyimide resin-modified silicone resin and an epoxy resin in a mass ratio of (3-5) / (1-2); The first auxiliary agent and the second auxiliary agent each independently include 2 to 6 parts of a curing agent and 0.5 to 3 parts of an antioxidant; The viscosity of the first binding glue is 8000-15000 cps, and the viscosity of the second binding glue is 800-10000 cps.

9. The rare earth target binding glue according to claim 8, characterized in that: At least one of the following conditions is met: The curing agent comprises dicyandiamide, latent modified imidazole and liquid aluminum dihydrogen phosphate in a mass ratio of (0.6-2) / (0.4-1) / (1-3); The antioxidant is selected from at least one of sodium phosphite, potassium phosphite and ammonium phosphite; The step of preparing the polyimide resin modified silicone resin comprises: adding the polyimide resin to the silicone resin according to the mass ratio of polyimide resin to silicone resin being (1-5) / (95-99), stirring at high speed, and centrifugally degassing to obtain the polyimide resin modified silicone resin.

10. A rare earth target binding method, characterized in that: The following steps are involved: Provide the rare earth target material binding adhesive as claimed in any one of claims 1 to 9, as well as a copper backing tube and a rare earth target material tube; Uniformly coating the first binding glue on the inner surface of the rare earth target tube to form a first glue layer; Evenly coating the second binding adhesive on the outer surface of the copper back tube to form a second adhesive layer; The rare earth target tube is sleeved outside the copper back tube, and rotated to make the first adhesive layer and the second adhesive layer bonded, and then left to stand and solidify to obtain a rare earth target; Wherein, the thickness of the first adhesive layer is 1-10 μm, and the thickness of the second adhesive layer is 1-3 mm.

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