A method for rigidly limiting low-stress bonding of vulnerable materials

Abstract

This invention discloses a method for low-stress bonding of vulnerable materials with rigid restraint, applied to quartz ceramic radomes. The method is suitable for bonding vulnerable materials and metal structures with simple surface structures, high processing precision, and assembly structures where the rigid restraint can be easily removed after the adhesive layer cures. This method controls the gap between the vulnerable material and the metal material through rigid restraint to meet design requirements and ensures a uniform gap. This allows the expansion stress of the metal structure to be released into the adhesive layer, thereby reducing the transmission of expansion stress to the vulnerable material. This invention provides a simple and clear method for low-stress bonding of vulnerable materials with rigid restraint, fundamentally solving the problem of cracking due to temperature changes after bonding and assembling vulnerable materials.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of radomes, in particular to a method for bonding fragile materials with steel limiting and low stress. BACKGROUND

[0002] In order to meet the wave permeability of different wave bands, more and more fragile materials are selected, such as quartz ceramic, silicon nitride, magnesium fluoride, zinc sulfide and yttrium magnesium complex phase. These materials are brittle materials and cannot be punched and assembled by screwing. Therefore, the metal materials are bonded and then assembled by screwing.

[0003] After being bonded by using the traditional bonding technology, the following problems exist: a) the coaxiality of the fragile material and the metal material cannot be guaranteed; b) the expansion stress of the metal causes the fragile material to crack due to the influence of temperature. The expansion coefficients of different materials are different, and the expansion stress is inevitable. The coaxiality of the two and the release of the expansion stress of the metal are the keys to the bonding of the fragile material. SUMMARY

[0004] The application aims to provide a method for bonding fragile materials with steel limiting and low stress. The thickness of the glue layer is effectively controlled by the steel limiting, the expansion stress of the metal is released in the glue layer, the uniformity of the glue layer is effectively controlled to guarantee the coaxiality of the two, and the technical problems that the coaxiality cannot be guaranteed and the fragile material is prone to cracking during bonding in the prior art are solved.

[0005] In order to achieve the above-mentioned purpose, the application adopts the following technical scheme:

[0006] The application provides a method for bonding fragile materials with steel limiting and low stress, which is applied to a quartz ceramic radome and includes the following steps:

[0007] Step S1, designing the thickness of the glue layer: according to the structure characteristics, thermal expansion coefficients and the like of the adhesive, the fragile material and the metal material structure, the effective thickness of the glue layer is designed and calculated through simulation;

[0008] Step S2, matching and processing: according to the designed effective thickness of the glue layer, the gap between the fragile material and the metal material structure is matched and processed;

[0009] Step S3, matching and assembling: the steel limiting is matched and assembled with the fragile material and the metal material structure, and the matching gap is verified;

[0010] Step S4, gluing: the adhesive is applied to the bonding surfaces of the fragile material and the metal material structure, and the thickness of the single-side glue layer is greater than the gap between the two;

[0011] Step S5, Assembly: Install the rigid limiter between the metal material structure and the vulnerable material after applying adhesive according to the markings. Perform the butt joint installation of the vulnerable material and the metal material structure and apply pressure. Pull the rigid limiter to judge whether the two are tightly fitted.

[0012] Step S6, Removal: Pull out the rigid limiter between the vulnerable material and the metal material structure and remove the limiter.

[0013] By designing an effective adhesive layer thickness, the expansion stress of the metal is released into the effective adhesive layer thickness, reducing the stress transmitted to vulnerable materials.

[0014] In some embodiments, the calculated effective adhesive layer thickness is 0.5 mm.

[0015] In some embodiments, the gaps in the processing of vulnerable materials and metal structures include the following steps:

[0016] Structural dimensions of rough-machined, easily damaged materials and metal structures;

[0017] After rough machining is completed, fine machining is performed according to the designed effective adhesive layer thickness to make the assembly gap between the two equal to the effective adhesive layer thickness.

[0018] In some embodiments, the rigid limiter is pre-assembled with vulnerable materials and metal structures for assembly, and the fitting clearance is verified, including the following steps:

[0019] Several rigid limiters made of enameled wire are placed on the bottom surface and side wall of the metal material structure;

[0020] By connecting the metal material structure with the vulnerable material, and pulling the rigid limit of the enameled wire, it can be determined whether the two are tightly connected.

[0021] Adjust the pressure position until all rigid limiters of the enameled wire are fully compressed;

[0022] All the rigid limiters of the enameled wire are pressed down, which satisfies the fit clearance requirements;

[0023] Once the clearance meets the requirements, mark the position of the rigid limit, and then disassemble to prepare for adhesive application.

[0024] In some embodiments, a plurality of rigid enameled wire supports are placed on the bottom surface and sidewalls of the metal material structure, including:

[0025] Eight rigid limiters are placed on the bottom surface of the metal structure;

[0026] Three rigid limiters are placed on the sidewall of the metal structure.

[0027] In some embodiments, before applying adhesive to the bonding surfaces of the vulnerable materials and the metal materials, the following steps are also included:

[0028] S3-1. Cleaning of bonding surfaces: Roughen the bonding surfaces of metal structures and easily damaged materials, and remove surface dirt and excess material with anhydrous ethanol cotton yarn;

[0029] S3-2, Primer application: Apply primer to the bonding surfaces of vulnerable materials and metal structures;

[0030] S3-3. Adhesive preparation: Prepare the adhesive according to the mixing ratio and operating instructions in the adhesive instructions.

[0031] In some embodiments, primer coating includes:

[0032] First, prepare the NJD-9 primer according to the ratio and stir it evenly. Apply the NJD-9 primer and let it air dry at room temperature for 45 minutes.

[0033] Then, apply NJD-11 primer and let it air dry at room temperature for 45 minutes.

[0034] In some embodiments, the compounding process includes compounding silicone rubber in a ratio of base paste: vulcanizing agent: catalyst = 100: 0.4-0.5: 1.0-1.1, and stirring until homogeneous and removing air bubbles.

[0035] In some embodiments, the assembly and disassembly steps also include:

[0036] S7. Curing: Allow to cure at room temperature for 7 days.

[0037] In some embodiments, the dismantling step further includes:

[0038] S8. Cleaning steps, including:

[0039] Use a single-edged blade to clean the excess adhesive squeezed out from the upper and lower surfaces of the joint between vulnerable materials and metal structures.

[0040] Compared with the prior art, the present invention has the following beneficial effects:

[0041] The present invention provides a method for low-stress bonding of vulnerable materials with rigid restraint. By pre-designing the adhesive layer thickness, the expansion stress of the metal is released into the effective adhesive layer thickness, reducing the stress transmitted to the vulnerable material. Adhesive is applied to both the bonding surfaces of the vulnerable material and the metal structure, solving the problem of insufficient adhesive and improving the wettability of the bonding surfaces, as well as increasing the drop speed during docking. The rigid restraint ensures uniform adhesive layer thickness and coaxiality of the vulnerable material and the metal structure. During docking, the rigid restraint is moved to determine whether the two are tightly bonded, ensuring coaxiality of the vulnerable material and the metal structure, and also ensuring uniform adhesive layer thickness. After assembly, removing the rigid restraint removes stress-relieving points. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of a product bonding process provided by an embodiment of the present invention, which involves a method for rigidly limiting low-stress bonding of vulnerable materials.

[0043] Figure 2 for Figure 1 A schematic diagram showing a partial cross-section of the middle section;

[0044] Figure 3 This is a flowchart illustrating a method for rigidly limiting low-stress bonding of vulnerable materials, provided as an embodiment of the present invention.

[0045] In the diagram: 1. Quartz ceramic cover; 2. Invar connecting ring; 3. Silicon rubber; 4. Rigid limiter of enameled wire. Detailed Implementation

[0046] Exemplary embodiments will be described more fully below with reference to the accompanying drawings; however, these exemplary embodiments may be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that the invention will be thorough and complete, and that those skilled in the art will fully understand the scope of the invention.

[0047] Where there is no conflict, the embodiments of the present invention and the features thereof can be combined with each other.

[0048] As used herein, the term “and / or” includes any and all combinations of one or more related enumerated entries.

[0049] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. The singular forms “a” and “the” used herein are also intended to include the plural forms unless the context clearly indicates otherwise. It will also be understood that when the terms “comprising” and / or “made of” are used in this specification, the presence of the stated features, integrals, steps, operations, elements, and / or components is specified, but the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or groups thereof is not excluded.

[0050] Unless otherwise specified, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art. It will also be understood that terms such as those defined in commonly used dictionaries should be understood to have the meaning consistent with their meaning in the context of the relevant art and the invention, and will not be understood to have an idealized or overly formal meaning unless expressly so defined herein.

[0051] To effectively control the coaxiality between the quartz ceramic cover and the Invar connecting ring, and to avoid the impact of metal expansion stress release on the expansion stress of the quartz ceramic cover, this invention provides a method for rigidly limiting low-stress bonding of vulnerable materials. To enable those skilled in the art to better understand the technical solution, the method for rigidly limiting low-stress bonding of vulnerable materials provided by this invention will be described in detail below with reference to the accompanying drawings.

[0052] like Figure 3 As shown, this invention provides a method for rigidly limiting low-stress bonding of vulnerable materials, applied to quartz ceramic radomes, comprising the following steps:

[0053] Step S1: Design the adhesive layer thickness: Based on the structural characteristics and thermal expansion coefficients of the adhesive, vulnerable materials, and metal materials, simulation is performed to design and calculate the effective adhesive layer thickness. By designing the effective adhesive layer thickness for vulnerable materials and metal materials, the expansion stress of the metal is released into the effective adhesive layer thickness, reducing the stress transmitted to the vulnerable materials. In some embodiments, the designed effective adhesive layer thickness is 0.5mm, meaning that the adhesive layer thickness between the vulnerable materials and the calculated material structure is uniform without any gradual changes. In this case, it is convenient for the rigid limit to be pulled out.

[0054] Specifically, in this embodiment, the vulnerable material is a quartz ceramic cover 1, the metal material structure is an Invar connecting ring 2, and the adhesive is HM-301 silicone rubber 3. That is to say, based on the structural characteristics and thermal expansion coefficients of HM-301 silicone rubber 3, quartz ceramic cover 1, and Invar connecting ring 2, the effective adhesive layer thickness is designed and calculated to be 0.5mm. It should be noted here that the 0.5mm thickness refers to the adhesive layer thickness between quartz ceramic cover 1 and Invar connecting ring 2.

[0055] Step S2, Matching and Processing: Based on the designed effective adhesive layer thickness, match the gap between the quartz ceramic cover 1 and the Invar connecting ring 2, and select the corresponding specification of rigid limiter according to the gap; it should be noted here that the rigid limiter is the rigid limiter 4 of the enameled wire;

[0056] Step S3, Assembly: Pre-assemble the rigid limiter 4 of the enameled wire with the quartz ceramic cover 1 and the Invar connecting ring 2, and verify the fit clearance;

[0057] The specific assembly steps are as follows:

[0058] like Figure 1 and Figure 2 As shown, according to the designed effective adhesive layer thickness, a suitable rigid limiter 4 for the enameled wire is placed on the bonding bottom end face and side wall of the Invar connecting ring 2, respectively. It should be noted that "suitable" means that the specification of the placed rigid limiter 4 for the enameled wire is equal to the designed effective adhesive layer thickness, so as to ensure that the rigid limiter 4 for the enameled wire can be equal to the effective adhesive layer thickness when pressure is applied.

[0059] After all the rigid limiters 4 of the enameled wires have been placed, install the quartz ceramic cover 1;

[0060] After placing the quartz ceramic cover 1 on the Invar connecting ring 2, pull the rigid limit 4 of the enameled wire to press it down. When all the rigid limit 4s of the enameled wire are pressed down, it indicates that the fit clearance between the quartz ceramic cover 1 and the Invar connecting ring 2 meets the requirements. Then mark the placement position of the rigid limit 4 of the enameled wire, then remove the quartz ceramic cover 1 from the Invar connecting ring 2, and then remove the rigid limit 4 of the enameled wire to complete the disassembly and prepare for gluing.

[0061] In some embodiments, before applying adhesive to the bonding surfaces of the quartz ceramic cover 1 and the Invar connecting ring 2, the following steps are also included:

[0062] S3-1. Cleaning the bonding surfaces: Roughen the bonding surfaces of the quartz ceramic cover 1 and the Invar connecting ring 2, and remove surface dirt and excess material with anhydrous ethanol cotton yarn.

[0063] S3-2, Primer application: Apply primer to the bonding surfaces of the quartz ceramic cover 1 and the Invar connecting ring 2 to improve the bonding strength;

[0064] S3-3. Rubber preparation: Prepare the rubber according to the preparation ratio and operating instructions in the HM-301 silicone rubber instruction manual.

[0065] Specifically, prepare the primer NJD-9 according to the ratio of A:B / 49:1 and stir it evenly.

[0066] In some embodiments, primer coating includes:

[0067] First, apply NJD-9 primer and let it air dry at room temperature for 45 minutes.

[0068] Then, apply NJD-11 primer and let it air dry at room temperature for 45 minutes.

[0069] Specifically, apply primer NJD-9 to the bonding surface of the quartz ceramic cover 1 and the Invar connecting ring 2, and let it air dry at room temperature for 45 minutes. Then apply primer NJD-11 and let it air dry at room temperature for 45 minutes.

[0070] In some embodiments, the compounding process includes compounding silicone rubber in a ratio of base paste: vulcanizing agent: catalyst = 100: 0.4-0.5: 1.0-1.1, and stirring until homogeneous and removing air bubbles.

[0071] The rigid limiter 4 of the enameled wire is pre-assembled with the quartz ceramic cover 1 and the Invar steel connecting ring 2 for assembly. The fitting clearance is verified, including the following steps:

[0072] Several rigid limiters 4 made of enameled wire are placed on the bottom end face and side wall of Invar connecting ring 2;

[0073] Connect the Invar connecting ring 2 to the quartz ceramic cover 1, and pull the rigid limit 4 of the enameled wire to determine whether the two are tightly connected.

[0074] Adjust the pressure position until all the rigid limiters 4 of the enameled wire are fully compressed;

[0075] All the rigid limiters 4 of the enameled wire are pressed down, which means that the fit clearance requirements are met;

[0076] Once the clearance meets the requirements, mark the position of the rigid limit, and then disassemble to prepare for adhesive application.

[0077] Several rigid enameled wire stops are placed on the bottom end face and side wall of the Invar connecting ring 2, including:

[0078] Eight rigid limiters are placed on the bottom end face of the Invar connecting ring 2;

[0079] Three rigid limiters are placed on the side wall of Invar connecting ring 2.

[0080] Step S4, Applying Adhesive: Apply adhesive to the bonding surfaces of the quartz ceramic cover 1 and the Invar connecting ring 2 respectively. The thickness of the adhesive layer on one side should be greater than the gap between the two. Specifically, the thickness of the adhesive layer on one side should be greater than 0.5 mm. It should be noted that the adhesive layer on one side refers to the thickness of the adhesive layer applied to the surfaces of the quartz ceramic cover 1 and the Invar connecting ring 2. By applying adhesive to both bonding surfaces of the quartz ceramic cover 1 and the Invar connecting ring 2, the wettability of the bonding surfaces of the quartz ceramic cover 1 and the Invar connecting ring 2 is improved, and the problem of insufficient adhesive is solved.

[0081] Step S5, Assembly: Install the rigid limiter 4 of the enameled wire between the glued metal structure and the vulnerable material according to the markings. Perform the butt joint installation of the vulnerable material and the metal structure, and apply pressure together. Specifically, the assembly steps are to place the rigid limiter in the marked positions according to the assembly sequence in Step S2, and then install the vulnerable material.

[0082] Step S6, Removal: Pull out the rigid limiter between the vulnerable material and the metal material structure and remove the limiter.

[0083] In some embodiments, the assembly and disassembly steps also include:

[0084] S7. Curing: Specifically, allow to cure at room temperature for 7 days.

[0085] Specifically, the demolition process also includes:

[0086] S8. Cleaning steps, including:

[0087] Cleaning excess adhesive squeezed out from the upper and lower end faces of the joint surfaces of vulnerable materials and metal structures using a single-edged blade also includes the following steps:

[0088] The present invention provides a method for achieving low-stress bonding using rigid limiting, which is applicable to assembly structures with simple bonding surfaces, high processing precision, and easy removal of rigid limiting components after the adhesive layer has cured.

[0089] The present invention provides a method for low-stress bonding of vulnerable materials with rigid restraint. By pre-designing the adhesive layer thickness, the expansion stress of the metal is released into the effective adhesive layer thickness, reducing the stress transmitted to the vulnerable material. Adhesive is applied to both the bonding surfaces of the vulnerable material and the metal structure, solving the problem of insufficient adhesive and improving the wettability of the bonding surfaces, as well as increasing the drop speed during docking. The rigid restraint ensures uniform adhesive layer thickness and coaxiality of the vulnerable material and the metal structure. During docking, the rigid restraint is moved to determine whether the two are tightly bonded, ensuring coaxiality of the vulnerable material and the metal structure, and also ensuring uniform adhesive layer thickness. After assembly, removing the rigid restraint removes stress-relieving points.

[0090] Example embodiments have been disclosed herein, and while specific terminology has been used, it is for general illustrative purposes only and should not be construed as limiting. In some embodiments, it will be apparent to those skilled in the art that features, characteristics, and / or elements described in connection with particular embodiments may be used alone, or in combination with features, characteristics, and / or elements described in connection with other embodiments, unless otherwise expressly indicated. Therefore, those skilled in the art will understand that various changes in form and detail may be made without departing from the scope of the invention as set forth by the appended claims.

Claims

1. A method for low stress bonding of a fragile material with a steel stopper, characterized in that, The application is applied to a quartz ceramic radome, and comprises the following steps: Step S1, designing the glue layer thickness: according to the adhesive, the vulnerable material, the structure characteristics and the thermal expansion coefficient of the metal material structure, the effective glue layer thickness is designed and calculated through simulation; Step S2, matching processing: according to the designed effective glue layer thickness, the gap between the vulnerable material and the metal material structure is matched and processed; Step S3, assembling: the steel limit is pre-assembled with the vulnerable material and the metal material structure, the assembly gap is verified, and the steel limit is marked; Step S4, gluing: the adhesive is applied to the bonding surfaces of the vulnerable material and the metal material structure, and the single-side glue layer thickness is greater than the gap between the two; Step S5, assembling: the steel limit is installed between the metal material structure and the vulnerable material after the glue is applied, the vulnerable material and the metal material structure are connected and installed, and the steel limit is pulled out to determine whether the two are tightly combined; Step S6, disassembling: the steel limit between the vulnerable material and the metal material structure is pulled out, and the limit is disassembled; The steel limit is pre-assembled with the vulnerable material and the metal material structure, the assembly gap is verified, and the assembly gap is verified, and the assembly gap is verified, and the assembly gap is verified, and the assembly gap is verified, and the assembly gap is verified, and the assembly gap is verified, and the assembly gap is verified, and the assembly gap is verified, and the assembly gap is verified, and the assembly gap is verified, and the assembly gap is 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The method of claim 1, wherein the method further comprises: ​ 3. The method of claim 1, wherein the method further comprises: ​ ​ ​ 4. The method of claim 1, wherein the method further comprises: ​ ​ ​ 5. The method of claim 1, wherein the method further comprises: ​ ​ ​ ​ 6. The method of claim 5, wherein the method further comprises: ​ ​ ​ 7. The method of claim 5, wherein the method further comprises: ​ 8. The method of claim 1, wherein the method further comprises: ​ S7, curing, air curing at room temperature for 7 days.

9. The method of claim 1, wherein the method further comprises: The removal step further comprises: S8, a cleaning step, comprising: Extruding excess glue from the upper and lower end faces of the joint between the fragile material and the metal material structure using a single-sided blade.

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