An assembly and integration method for a high-precision neutron supermirror guide tube

Abstract

The present invention relates to an assembly and integration method for a high-precision neutron supermirror duct. The method includes: placing multiple neutron supermirror reflecting surfaces on a reference panel with high flatness, and placing a long back plate thereon. Between the long back plate and the reference panel, a neutron duct wall is formed. Then, four neutron duct walls are jointly abutted against a high-precision support body. After measurement to ensure dimensional accuracy, the four neutron supermirror duct walls are fixed into a whole, cured, and the support body is removed to obtain a neutron supermirror duct. Finally, a high-precision U-shaped fixture is machined, and the relative attitude between two neutron supermirror ducts is adjusted to complete the alignment of the two neutron supermirror ducts. Compared with the prior art, the advantages of the present invention are that by real-time measurement, parameters such as the duct diameter size, parallelism, and perpendicularity are ensured to be in the order of dozens of micrometers, the flatness of the duct wall reaches the sub-milliarcsecond level, and the high-precision support body can be reused, which is easy for batch production.

Description

Technical Field

[0001] The present invention relates to the field of precision instrument and equipment manufacturing, and particularly to an assembly and integration method for a high-precision neutron supermirror duct. Background Art

[0002] Neutron scattering technology requires a continuous generation of neutrons from a neutron source. Currently, neutron sources in the world are divided into two categories. One is a spallation neutron source, which generates neutrons by accelerating protons with an accelerator to bombard a metal target. The other is a reactor neutron source, which generates neutrons based on uranium fission. Whether it is a spallation neutron source or a reactor neutron source, multiple neutron supermirror ducts are required to lead out as many neutrons generated by the neutron source to the outside as possible to ensure the neutron flux. Therefore, neutron supermirror ducts have become an essential scientific instrument and equipment in neutron physics engineering.

[0003] Due to the limitations of coating technology, currently, in neutron supermirror ducts, multiple neutron supermirrors are generally spliced to form a relatively long neutron duct wall, and four neutron duct walls are further integrated into a neutron supermirror duct. On this basis, multiple neutron supermirror ducts are assembled and used. Since the neutron reflection of the neutron supermirror is realized based on the Bragg diffraction of multiple layers of films under grazing incidence conditions, and the working cross-section of the neutron supermirror is very small under grazing incidence conditions, extremely high requirements are imposed on the accuracy of neutron supermirror splicing, neutron duct wall integration, and neutron supermirror duct assembly (such as aperture size, parallelism, perpendicularity, and duct wall flatness, duct assembly accuracy, etc.). For example, requirements for aperture size, parallelism, and perpendicularity reach the order of dozens of micrometers, and the requirement for duct wall flatness reaches the order of sub-milliradians. This poses very high requirements for the assembly and integration accuracy of neutron supermirror ducts, and currently, there is a lack of effective assembly and integration methods. For example, invention patents such as ZL201810345548.8 and ZL201911001268.6, ZL201810345551.X and ZL201810345550.5 only support and adjust the already prepared neutron supermirror ducts, and do not involve the high-precision assembly of the neutron supermirror ducts themselves. Summary of the Invention

[0004] The purpose of the present invention is to overcome the above-mentioned defects existing in the prior art and provide an assembly and integration method for a high-precision neutron supermirror duct. This method can achieve the high-precision assembly and integration of neutron supermirror ducts, and at the same time can be quickly implemented and is easy to realize the mass production of neutron supermirror ducts.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] The present invention provides an assembly and integration method for a high-precision neutron supermirror duct, and the specific steps include:

[0007] S1: Assembling the neutron guide tube wall: Place at least one neutron supermirror on the reference panel, and place a long backplate on the neutron supermirror. The length of the long backplate is shorter than the total length of the neutron supermirror, and the protruding part of the neutron supermirror serves as the reserved neutron supermirror adjustment surface. Inject glue between the long backplate and the reference panel, and after curing, obtain the neutron guide tube wall;

[0008] S2: Assembling the neutron supermirror guide tube: Repeat S1 to assemble the neutron supermirror guide tube wall, and obtain four neutron supermirror guide tube walls. Press the four neutron supermirror guide tube walls against a high-precision machining fixture that matches the design dimensions of the four neutron supermirror guide tube walls. Measure the dimensions, parallelism, and perpendicularity parameters between the four neutron supermirror guide tube walls, and adjust their precision to meet the design requirements. Then fix the four neutron supermirror guide tube walls by injecting glue or tightening with screws, and then remove the high-precision machining fixture to obtain the neutron supermirror guide tube;

[0009] S3: Assembling two neutron supermirror guide tubes: Repeat S2 to assemble the neutron supermirror guide tube, and obtain two supermirror guide tubes. Place a high-precision machining U-shaped fixture with machining dimensions matching the neutron supermirror guide tube on the reserved neutron supermirror adjustment surface; Place the two neutron supermirror guide tubes in sequence, and adjust the relative posture between the two neutron supermirror guide tubes so that the high-precision machining U-shaped fixture can clamp the reserved neutron supermirror adjustment surfaces of the two neutron supermirror guide tubes at the same time, and complete the adjustment of the two neutron supermirror guide tubes;

[0010] S4: Repeat S1 and S2 to obtain the required number of neutron supermirror guide tubes, and repeat S3 to assemble multiple neutron supermirror guide tubes to meet different length requirements for the neutron supermirror guide tubes.

[0011] Further, in S2, the dimensional accuracy between the four neutron supermirror guide tube walls is measured in real time by a coordinate measuring machine or a laser tracker and then corrected.

[0012] Further, test the high-precision machining fixture, the neutron supermirror guide tube wall, and the diameter of the neutron supermirror guide tube by a coordinate measuring machine to ensure that the surface shape accuracy of the neutron supermirror guide tube wall is in the order of hundreds of microns and the diameter of the neutron supermirror guide tube reaches within fifty microns.

[0013] Further, calibrate by a coordinate measuring machine to establish the relative position relationship between the target component and the target seat in three-dimensional space. Adjust the position of the target component by adjusting the target seat, and calibrate the neutron supermirror and the high-precision machining fixture to obtain the theoretical position coordinates of the neutron supermirror guide tube target seat and the high-precision machining fixture target seat in space.

[0014] Further, when performing three - coordinate testing on the S2 using a coordinate measuring machine after calibration, first, adjust the positioning and assemble the neutron supermirror catheter. Place the neutron supermirror on the catheter support steel plate fixed on the horizontal reference platform, and splice the neutron supermirrors to form a neutron supermirror catheter with the four sides of the highly calibrated high - precision processing support body as the reference, and then fix the neutron supermirror catheter. Secondly, use three - coordinate testing to adjust the attitude of the assembled neutron supermirror catheter unit: adjust the screw so that the coordinate measurement value of the neutron supermirror target seat deviates from the theoretical coordinate by less than 0.05 mm, and then inject glue to fix the neutron supermirror catheter. Then conduct a review. Use a three - coordinate measuring arm to measure the target seat on the inner wall of the neutron supermirror catheter for the neutron supermirror catheter after gluing, and review the spatial position accuracy of the core components to ensure that the coordinate error between its measurement value and the theoretical value is less than 0.05 mm. Finally, disassemble. After completing the attitude adjustment, inject glue at the glue injection port to form a fixing glue layer to fix the catheter. Then, let the catheter stand still. After the glue solidifies, remove the high - precision processing support body and the catheter support steel plate in sequence.

[0015] Further, the neutron supermirror is made of float glass coated with Ni / Ti or Ni / N / Ti multilayer film.

[0016] Further, the long backplane is made of tempered glass, stainless steel or aluminum alloy material.

[0017] Further, the glue is made of epoxy resin or ultraviolet photosensitive glue material.

[0018] Further, the reference panel is a reference panel using a plasticizing process.

[0019] Further, inject liquid nitrogen into the high - precision processing support body to cool it and then remove the high - precision processing support body.

[0020] Compared with the prior art, the present invention has the following advantages:

[0021] (1) High precision in neutron supermirror splicing, neutron catheter wall integration, and neutron supermirror catheter assembly. Through the coordinated cooperation of the reference panel with high flatness, the long backplane, and the high - precision support body, as well as the real - time measurement of the coordinate measuring machine and the laser tracker, the present invention ensures that the accuracy of the aperture size, parallelism, and perpendicularity of the neutron supermirror catheter reaches the order of several tens of micrometers, and the flatness of the catheter wall reaches the order of sub - milliradians. Through this alignment method, a neutron supermirror catheter with ultra - high precision is obtained.

[0022] (2) The high-precision body and external tooling can be reused, making it easy to quickly achieve the assembly and integration of neutron supermirror ducts and suitable for mass production. For the requirements of the caliber and length of neutron supermirror ducts with different design values, multi-dimensional adjustment of the body and external tooling can be relied on for coordination. The integrated assembly method of the present invention not only ensures the high precision of neutron supermirror ducts, but also ensures the rapidity of the process and operation. The reusable and replaceable tooling reduces costs while solving the problem of inability to produce in large quantities. Description of the Drawings

[0023] Figure 1 It is the reflectivity curve graph of the multi-layer film structure of the neutron supermirror reflecting surface.

[0024] Figure 2 It is the schematic diagram of the splicing of the neutron supermirror duct wall.

[0025] Figure 3 It is the schematic diagram of the high-precision machining body and an example of machining requirements.

[0026] Figure 4 It is the schematic diagram of the splicing of the neutron supermirror duct wall.

[0027] Figure 5 It is the schematic diagram of the overall structure of the neutron supermirror duct.

[0028] Figure 6 It is the schematic diagram of the machining requirements of the high-precision machining U-shaped fixture in the embodiment.

[0029] Figure 7 It is the schematic diagram of the high-precision machining U-shaped fixture clamping the neutron supermirror duct.

[0030] Figure 8 It is the 3D schematic diagram of the surface shape of the neutron supermirror duct wall (including the height at the joint).

[0031] Figure 9 It is the 3D schematic diagram of the caliber of the segmented focusing duct.

[0032] Reference Signs: 1. Long back plate; 2. Neutron supermirror; 3. High flatness reference panel; 4. Glue injection gap; 5. Reserved working surface of U-shaped fixture; 6. Contact surface between high-precision machining body and neutron supermirror duct wall; 7. High-precision machining body; 8. High-precision machining U-shaped fixture; 9. Contact surface between high-precision machining U-shaped fixture and alignment surface of neutron supermirror. Detailed Embodiments

[0033] The present invention will be described in detail below with reference to the drawings and specific embodiments. Features such as component models, material names, connection structures, control methods, algorithms, etc. that are not clearly described in the present technical solution are regarded as common technical features disclosed in the prior art.

[0034] Example 1

[0035] This example provides an assembly and integration method for a high-precision neutron supermirror catheter, and its steps are as follows:

[0036] S1: Assemble the neutron supermirror catheter wall: As Figure 2 shown, place two neutron supermirrors 2 on a high flatness reference panel 3, and place a long backplate 1 on the neutron supermirror 2. The length of the long backplate 1 is shorter than the total length of the neutron supermirror 2, so as to form a reserved U-shaped fixture working surface at both ends of the neutron supermirror catheter wall. Inject glue into the glue injection gap 4 between the long backplate 1 and the high flatness reference panel 3, and after curing, obtain the neutron supermirror catheter wall;

[0037] S2: Assemble the neutron supermirror catheter: Repeat S1 to assemble the neutron supermirror catheter wall to obtain four neutron supermirror catheter walls. Top the four neutron supermirror catheter walls against the contact surface 6 between the high-precision machined body and the neutron supermirror catheter wall that matches the design dimensions of the four neutron supermirror catheter walls. In this example, the dimension design of the high-precision machined body 7 is as Figure 3 shown. Measure the dimensions, parallelism, and perpendicularity parameters between the four neutron supermirror catheter walls, and adjust their accuracy to meet the design requirements. As Figure 4 shown, fix the four neutron supermirror catheter walls by injecting glue or tightening screws, and then remove the high-precision machined body 7 to obtain the neutron supermirror catheter, as Figure 5 shown;

[0038] S3: Assemble two neutron supermirror catheters: Repeat S2 to assemble the neutron supermirror catheter to obtain two neutron supermirror catheters. Place a high-precision machined U-shaped fixture 8 with machining dimensions matching the neutron supermirror catheter on the reserved U-shaped fixture working surface 5. The machining dimensions of the high-precision machined U-shaped fixture 8 are as Figure 6 shown; As Figure 7 shown, place the two neutron supermirror catheters in sequence, and adjust the relative attitude between the two neutron supermirror catheters. The high-precision machined U-shaped fixture 8 clamps the reserved U-shaped fixture working surface 5 of one neutron supermirror catheter, and at the same time clamps the other neutron supermirror catheter through the contact surface 9 between the high-precision machined U-shaped fixture and the neutron supermirror alignment surface to complete the alignment of the two neutron supermirror catheters;

[0039] S4: Repeat S1 and S2 to obtain the required number of neutron supermirror catheters, and repeat S3 to assemble multiple neutron supermirror catheters to meet different length requirements for the neutron supermirror catheters.

[0040] Among them, in order to ensure the high precision required by the project, a coordinate measuring machine is used to test the high-precision machining support body, the wall of the neutron supermirror catheter, and the diameter of the neutron supermirror catheter, ensuring that the surface profile accuracy of the neutron supermirror catheter wall reaches the order of hundreds of micrometers and the diameter accuracy of the neutron supermirror catheter is within fifty micrometers. The parameters are shown in Table 1 for details.

[0041] Table 1 Parameters of the Port Diameter of the Neutron Supermirror Catheter

[0042]

[0043] The specific coordinate measuring steps include:

[0044] First: Calibration. The calibration is to establish the relative position relationship between the target component and the target seat in the three-dimensional space. By adjusting the target seat, the position of the target component is adjusted, and the neutron supermirror 2 and the high-precision machining support body 7 are calibrated. First, calibrate the neutron supermirror 2: Place the neutron supermirror 2 on the optical platform, use the measuring arm to measure the front and rear end faces and the inner side faces of the front and rear ends of the neutron supermirror 2, and then measure the target seat on the neutron supermirror 2 to establish the spatial position relationship between the inner size of the neutron supermirror catheter and the target seat on the neutron supermirror 2. Since the processing and splicing accuracy of the inner wall surface of the neutron supermirror catheter is high and the theoretical position of the inner wall surface in space is known, the theoretical position coordinates of the target seat of the neutron supermirror catheter in space can be obtained.

[0045] Secondly, calibrate the high-precision machining support body 7: Install the neutron supermirror 2 inside the outer support mechanism provided with the metal shell adjustment component to achieve basic coaxiality. Through the surface contact between the two, the wall of the neutron supermirror catheter and the high-precision machining support body 7 form an integral body without relative movement. Place the outer support mechanism equipped with the neutron supermirror 2 on the optical platform, use the measuring arm to measure the target seat of the high-precision machining support body 7 and the target seat of the inner wall of the neutron supermirror catheter, establish the theoretical position relationship between the target seats, and obtain the theoretical position coordinates of the target seat of the high-precision machining support body 7 in space.

[0046] Then, directly obtain the theoretical position coordinates of the bracket target seat in space using the drawing dimensions.

[0047] Second: Adjust the position and assemble the neutron supermirror catheter. First, place the catheter support steel plate on the horizontal reference platform and fix it with the reference block; then place a neutron supermirror on the catheter support steel plate, and use the four sides of the calibrated high-precision machining support body 7 as the reference to closely join multiple neutron supermirrors 2 in sequence against the reference surface to form a rectangular tubular neutron supermirror catheter; then clamp the surface contact pressing mechanism at both ends of the neutron supermirror catheter and press it tightly through the threaded fit with the catheter support steel plate to fix the neutron supermirror catheter and complete the assembly.

[0048] Third: Use three - coordinate measurement to adjust the attitude of the assembled neutron supermirror catheter unit, including: the position coordinates of the target seat, adjust the top adjustment screw, left - hand adjustment screw, and right - hand adjustment screw. When the deviation between the measured value of the target seat coordinates and the calibrated theoretical coordinates is less than 0.05 mm, the neutron supermirror 2 is installed in the theoretical position. Finally, inject glue at the glue injection port to form a glue layer with a thickness of 0.5 mm to fix the neutron supermirror catheter.

[0049] Fourth: Re - check and disassembly and assembly. After gluing the neutron supermirror catheter, use a three - coordinate measuring arm to measure the target seat located on the inner wall of the neutron supermirror catheter. Re - check the spatial position accuracy of the core components. When it is determined that the coordinate error between the measured value and the theoretical value is less than 0.05 mm, the installation and adjustment work is completed. If the deviation between the measured value and the theoretical value is greater than 0.05 mm, it is necessary to destroy the calibration relationship between the neutron supermirror catheter and the integrated device. Directly fine - tune the neutron supermirror catheter through the adjustment screws in the integrated device adjustment component until the error between the measured value of the target seat on the inner wall of the neutron supermirror catheter and the calibrated theoretical value is less than 0.05 mm. And repeat the above - mentioned third step until the requirements are met.

[0050] Fifth: Disassembly and assembly. After the attitude adjustment is completed, inject glue at the glue injection port to form a fixing glue layer to achieve the fixation of the catheter. Finally, let the catheter stand still. After the glue solidifies, remove the high - precision processing support body and the catheter support steel plate in sequence.

[0051] Sixth: Assembly and adjustment. After the adjustment of the neutron supermirror catheter is completed, splice the two sections of the catheter into one section. Place the high - precision processed U - shaped clamp 8 at the reserved U - shaped clamp working surface 5 at the port docking. Place the two neutron supermirror catheters in sequence and adjust the relative attitude between the two neutron supermirror catheters so that the U - shaped clamp can clamp the two reserved U - shaped clamp working surfaces 5 simultaneously to complete the assembly and adjustment of the two neutron supermirror catheters.

[0052] Specifically, the parameters of the neutron supermirror catheter prepared by this method are designed and completed according to the specific standards of the project. The total length of a single neutron supermirror catheter is 1 meter, the caliber is 30 mm×30 mm, and the requirements for caliber size, parallelism, and perpendicularity reach the order of dozens of micrometers. The flatness requirement of the neutron supermirror catheter wall reaches the order of sub - milliradians. The specific content includes:

[0053] Design the neutron supermirror. The design of the neutron supermirror requires first purchasing the substrate material (size accuracy: 3 mm), using a high - precision surface grinder to precisely polish the substrate (size accuracy: 0.2 mm), and then performing complex - frequency ultrasonic cleaning on the polished substrate: ultrapure water→acid cleaning solution→ultrapure water→neutral cleaning solution→ultrapure water→nitrogen drying, so that the substrate waviness error ≤ 1.0×10 -4 ; Secondly, deposit on the substrate as Figure 1The nickel-titanium thin film with M = 2, Rc ≥ 87%, and uniformity ≥ 5% as shown; finally, two 500-mm neutron supermirrors 2 are inverted on the reference platform, glue is applied to the back of the neutron supermirrors, and the center of the backplane is made to coincide with the center of the neutron supermirrors through the splicing device. Under the dual action of external fixation and internal gluing, the splicing of the duct wall of the neutron supermirror unit is completed, forming a neutron supermirror unit duct wall with a total length of 1000 mm. The neutron supermirror unit duct wall meets the standards shown in Figure 8 , Figure 9 : the seam width of the two 500-mm supermirrors is ≤ 0.05 mm, the height difference at both ends of the seam is ≤ 0.01 mm, and the PV of the overall surface shape is ≤ 0.1 mm; the neutron supermirror duct meets the standards that the parallelism of the opposite surfaces of the two neutron supermirror unit duct walls is ≤ 1×10 -4 Rad, the perpendicularity of adjacent surfaces is ≤ 1×10 -4 Rad, and the dimensional accuracy of the duct interface is 0.01 mm.

[0054] The above description of the embodiments is for the convenience of those of ordinary skill in the art to understand and use the invention. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative efforts. Therefore, the present invention is not limited to the above embodiments, and the improvements and modifications made by those skilled in the art without departing from the scope of the present invention should be within the protection scope of the present invention.

Claims

1. An assembly and integration method for a high-precision neutron supermirror duct, characterized in that The specific steps include: S1: Assemble the neutron guide tube wall: Place at least one neutron supermirror on the reference panel, and place a long back plate on the neutron supermirror. The length of the long back plate is shorter than the total length of the neutron supermirror. The part of the neutron supermirror that extends beyond the long back plate serves as the reserved neutron supermirror alignment surface. Then, inject glue between the long back plate and the reference panel, and after curing, obtain the neutron guide tube wall. S2: Assemble the neutron supermirror tube: Repeat S1 to assemble the neutron supermirror tube wall, obtaining four neutron supermirror tube walls. Press the four neutron supermirror tube walls against a high-precision machining fixture that matches the designed dimensions of the neutron supermirror tube wall. Measure the dimensions, parallelism, and perpendicularity parameters between the four neutron supermirror tube walls, and adjust their precision to meet the design requirements. Then, fix the four neutron supermirror tube walls by injecting glue or using fasteners, and then remove the high-precision machining fixture to obtain the neutron supermirror tube. S3: Assemble two neutron supermirror tubes: Repeat S2 to assemble the neutron supermirror tube, obtaining two supermirror tubes. Place a high-precision machining U-shaped fixture with machining dimensions matching the neutron supermirror tube on the reserved neutron supermirror alignment surface. Place the two neutron supermirror tubes in sequence, and adjust the relative posture between the two neutron supermirror tubes so that the high-precision machining U-shaped fixture can simultaneously clamp the reserved neutron supermirror alignment surfaces of the two neutron supermirror tubes, completing the alignment of the two neutron supermirror tubes. S4: Based on the assembly requirements for the target quantity / length of the neutron supermirror tubes, repeat S3 to assemble multiple neutron supermirror tubes. In S2, the dimensional accuracy between the four neutron supermirror tube walls is corrected after being measured in real time by a coordinate measuring machine or a laser tracker. In S2, use a coordinate measuring machine to test the high-precision machining fixture, the neutron supermirror tube wall, and the neutron supermirror tube diameter, so that the surface shape accuracy of the neutron supermirror tube wall is on the order of hundreds of micrometers, and the neutron supermirror tube diameter is within fifty micrometers.

2. The assembly and integration method of a high-precision neutron supermirror catheter according to claim 1, characterized in that, In S2, before the coordinate measuring machine performs three-coordinate testing, calibrate it through the coordinate measuring machine to establish the relative position relationship between the target component and the target seat in three-dimensional space. Adjust the position of the target component by adjusting the target seat, and calibrate the neutron supermirror and the high-precision machining fixture to obtain the theoretical position coordinates of the neutron supermirror tube target seat and the high-precision machining fixture target seat in space.

3. The assembly and integration method of a high-precision neutron supermirror catheter according to claim 2, characterized in that, In S2, after calibration, when performing three-coordinate testing by the coordinate measuring machine, it includes the following steps: T1: Adjust the position and assemble the neutron supermirror tube. Place the neutron supermirror on the tube support steel plate on the horizontal reference platform, and splice the neutron supermirrors to form a neutron supermirror tube with the four sides of the calibrated high-precision machining fixture as the reference, and fix the neutron supermirror tube. T2: Use three-coordinate testing to adjust the posture of the assembled neutron supermirror tube unit: Make the coordinate measurement value of the neutron supermirror target seat deviate from the theoretical coordinate by less than 0.05 mm, and then inject glue to fix the neutron supermirror tube. T3: After the neutron supermirror catheter is glued, use a coordinate measuring arm to measure the target seat on the inner wall of the neutron supermirror catheter, review the spatial position accuracy of the core components, and ensure that the coordinate error between the measured value and the theoretical value is less than 0.05 mm. T4: After the attitude adjustment is completed, inject glue into the glue injection port to form a fixing glue layer to fix the catheter. Then, let the catheter stand still. After the glue solidifies, remove the high-precision processing support body and the catheter support steel plate in sequence.

4. The assembly and integration method of a high-precision neutron supermirror catheter according to claim 1, characterized in that In S1, the neutron supermirror uses float glass coated with Ni / Ti or Ni / N / Ti multilayer film.

5. An assembly and integration method for a high-precision neutron supermirror catheter according to claim 1, characterized in that, In S1, the long backplane uses tempered glass, stainless steel or aluminum alloy material.

6. The assembly and integration method of a high-precision neutron supermirror catheter according to claim 1, characterized in that In S1 and S2, the glue uses epoxy resin or ultraviolet photosensitive glue material.

7. An assembly and integration method for a high-precision neutron supermirror catheter according to claim 1, characterized in that In S1, the reference panel uses a reference panel with a plasticizing process.

8. The assembly and integration method of a high-precision neutron supermirror catheter according to claim 1, characterized in that In S2, after injecting liquid nitrogen into the high-precision processing support body to cool it, remove the high-precision processing support body.

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