Non-magnetic vacuum flange connector and manufacturing method

Abstract

The present application belongs to the technical field of optical glass vacuum chamber, and relates to a non-magnetic vacuum flange connecting piece and a manufacturing method. A sapphire glass piece with holes is used to connect between a non-magnetic metal CF flange and a hollow quartz glass round tube, the metal CF flange and the sapphire glass piece are welded together through a vacuum brazing process, the sapphire glass piece and the hollow quartz glass round tube are connected together through a photo-cementing method, and then a deep photo-cementing process is used to make the connection of the two after photo-cementing more firm, almost becoming an integral whole, thus forming a vacuum seal. Since the sapphire glass piece and the metal flange are connected and sealed through a vacuum brazing process, they have good high-temperature resistance, and the maximum baking temperature can reach 450 DEG C. After the other end of the connecting piece glass tube is deep photo-cemented with a processed vacuum glass chamber and then connected to a vacuum pumping device through the CF flange, an ultrahigh vacuum glass chamber can be made for cold atom vacuum experiments.

Description

Technical Field

[0001] This invention belongs to the field of optical glass vacuum cavity technology, and relates to a non-magnetic vacuum flange connector and its manufacturing method. Background Technology

[0002] It is widely used in cold atom ultra-high vacuum chambers. The cold atom vacuum chamber and the CF flange are connected by hollow glass. One end is glued to the hollow quartz glass tube. The glass tube needs to be sealed to the alloy CF flange before the CF flange can be connected to the vacuum equipment. After evacuation, the vacuum level needs to reach 1×10⁻⁶. -10 Currently, there are two methods for connecting the two components. One method involves high-temperature firing of a hollow glass tube and an alloy flange hollow tube together. The hollow tube of the alloy flange is typically made of 4J29 Kovar alloy, but this metal is magnetic and cannot be used in vacuum experiments where it is highly sensitive to cold atomic magnetism. The second method uses indium sealing or sealant sealing. However, since indium has a melting point of 156°C and sealant generally has a maximum temperature resistance of no more than 200°C, workpieces made using either sealing method cannot be used for high-temperature baking experiments above 200°C. Therefore, to achieve a non-magnetic metal flange connection at high temperatures, the metal flange material generally needs to be non-magnetic 316L or titanium alloy, and the hollow glass tube material generally needs to be quartz glass or borosilicate glass. However, due to the large difference in thermal expansion coefficients between titanium alloy and quartz glass or borosilicate glass, the hollow glass tube will crack after high-temperature firing and cooling to room temperature, rendering it unusable. Therefore, these two materials cannot be fired together at high temperatures. Thus, the solution lies in how to connect a non-magnetic metal CF flange and a hollow quartz glass tube together. Summary of the Invention

[0003] The purpose of this invention is to provide a non-magnetic vacuum flange connector and its manufacturing method, so as to solve the technical problem in the prior art that it is impossible to connect a non-magnetic metal CF flange and a hollow quartz glass tube together.

[0004] To achieve the above objectives, the present invention employs the following technical solution:

[0005] In a first aspect, this application discloses a method for manufacturing a non-magnetic vacuum flange connector, comprising:

[0006] After machining a through hole in the center of the sapphire glass sheet, a copper-based metal oxide film with a thickness of 0.08-0.12mm is sintered at high temperature on the outer cylindrical surface of the sapphire glass sheet; the two connecting surfaces at both ends of the sapphire glass sheet are polished to obtain the polished sapphire glass sheet; the CF flange and hollow quartz glass tube are pretreated.

[0007] One of the connecting surfaces of the polished sapphire glass sheet contacts the CF flange and is vacuum brazed to form an integral flange-glass sheet; the other connecting surface is polished to meet the requirements of the adhesive, forming the A side of the sapphire glass sheet;

[0008] The pre-treated hollow quartz glass tube is bonded to the A side of a sapphire glass sheet with a light adhesive to form a connector; the connector is then placed in a constant temperature furnace for constant temperature deepening of the light adhesive treatment to obtain a non-magnetic vacuum flange connector.

[0009] Preferably, after machining a through hole in the center of the sapphire glass sheet, chamfers are machined on both sides of the hole, and a step is machined on the side that contacts the CF flange to match the CF flange; the inner wall of the through hole and the chamfers on both sides are polished until there are no visible pits.

[0010] Preferably, a copper-based metal oxide film with a thickness of 0.08-0.12 mm is sintered at high temperature on the outer cylindrical surface of the sapphire glass sheet, specifically including:

[0011] Apply high-temperature resistant sintering prevention paste evenly to the two connecting surfaces and the stepped circular surface of the sapphire glass sheet;

[0012] After the high-temperature sintering prevention paste has cured, the sapphire glass slide is placed in a vacuum furnace and heated to 1050-1200℃. A copper-based metal oxide film with a thickness of 0.08-0.12mm is uniformly sintered on the outer surface. The high-temperature sintering prevention paste applied to the sapphire glass slide is then scraped off.

[0013] Preferably, the two connecting surfaces at both ends of the sapphire glass sheet are first ground and then polished, with each surface having a thickness of 0.1-0.15mm removed; the A surface of the sapphire glass sheet is free of scratches under a 20x microscope.

[0014] Preferably, the pretreatment of the CF flange specifically involves machining a flange knife edge on one side of the CF flange and machining a stepped hole on the other side to match the sapphire glass sheet.

[0015] Preferably, one connecting surface of the polished sapphire glass sheet contacts the CF flange, and the flange-glass sheet are formed by vacuum brazing, specifically including:

[0016] The polished sapphire glass sheet is placed in the stepped hole of the CF flange. A ring of amorphous copper solder sheet is placed in the gap between the sapphire glass sheet and the CF flange. A layer of oxygen-free copper brazing paste is evenly applied above the gap to form the component to be processed.

[0017] The components to be processed are placed in a vacuum brazing furnace and heated to 630-710℃. Vacuum brazing yields an integrated flange-glass sheet.

[0018] Preferably, the pretreated hollow quartz glass tube specifically includes:

[0019] Take a hollow glass tube made of quartz glass, and grind and polish both ends until they meet the requirements for gloss adhesive, requiring aperture N=-0.2 and defect level II; under a 20x microscope, there are no scratches on the entire gloss adhesive surface, and the polished surface is evenly coated with waterproof protective paint.

[0020] Preferably, the temperature at which the connector is placed in a constant temperature oven for constant temperature deepening of the photoresist is 200-230°C, and the time is 4-6 hours.

[0021] Secondly, this application discloses a non-magnetic vacuum flange connector, which is manufactured using the manufacturing method of a non-magnetic vacuum flange connector described in any one of the above claims.

[0022] Preferably, the non-magnetic vacuum flange connector includes a CF flange, a sapphire glass plate welded inside the CF flange, one end of a hollow quartz glass tube fixed to the sapphire glass plate, the other end of the hollow quartz glass tube being sealed with a perforated surface of the vacuum glass chamber using a glossy adhesive, and one end of the CF flange being sealed with an oxygen-free copper sealing ring to the vacuum pump, forming a closed vacuum chamber.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] This application discloses a method for manufacturing a non-magnetic vacuum flange connector. A sapphire glass sheet with a central hole is used to connect a non-magnetic metal CF flange and a hollow quartz glass tube. The CF flange and the sapphire glass sheet are welded together using a vacuum brazing process. The sapphire glass sheet and the hollow quartz glass tube are then connected together using a light-adhesive method. Further refinement of the light-adhesive process further strengthens the connection, making them almost a single unit, thus forming a vacuum seal. Because the sapphire glass sheet and the metal flange are connected and sealed using a vacuum brazing process, they exhibit excellent high-temperature resistance, with a maximum baking temperature reaching 450°C. One end of this connector connects to a vacuum glass chamber, and the other end connects to a vacuum pumping device via a CF flange, enabling the creation of an ultra-high vacuum chamber for cold atom vacuum experiments. Attached Figure Description

[0025] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a flowchart of a method according to an embodiment of the present invention;

[0027] Figure 2 This is a schematic diagram of the structure of the non-magnetic vacuum flange connector according to an embodiment of the present invention;

[0028] Figure 3 This is a schematic diagram of the CF flange structure according to an embodiment of the present invention;

[0029] Figure 4 This is a schematic diagram of the sapphire glass sheet structure according to an embodiment of the present invention;

[0030] Figure 5 This is a schematic diagram of the hollow quartz glass tube structure according to an embodiment of the present invention;

[0031] Figure 6 This is a schematic diagram of the brazing of the CF flange and sapphire glass sheet in an embodiment of the present invention.

[0032] Wherein: 1-Hollow quartz glass tube; 2-Sapphire glass sheet; 3-CF flange; 4-Amorphous copper solder sheet. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0034] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0035] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0036] In the description of the embodiments of the present invention, it should be noted that if terms such as "upper," "lower," "horizontal," or "inner" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. Furthermore, terms such as "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0037] Furthermore, the use of the term "horizontal" does not imply that the component must be absolutely horizontal, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0038] In the description of the embodiments of the present invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the present invention according to the specific circumstances.

[0039] The present invention will now be described in further detail with reference to the accompanying drawings:

[0040] See Figure 1 This application discloses a method for manufacturing a non-magnetic vacuum flange connector, comprising:

[0041] S1: After machining a through hole in the center of the sapphire glass sheet 2, a copper-based metal oxide film with a thickness of 0.08-0.12mm is sintered at high temperature on the outer cylindrical surface of the sapphire glass sheet 2; the two connecting surfaces at both ends of the sapphire glass sheet 2 are polished to obtain the polished sapphire glass sheet 2; the CF flange 3 and the hollow quartz glass tube 1 are pretreated.

[0042] S2: One connecting surface of the polished sapphire glass sheet 2 contacts the CF flange 3 and is vacuum brazed to form an integral flange-glass sheet; the other connecting surface is polished to meet the requirements of the adhesive to form the A side of the sapphire glass sheet;

[0043] S3: Apply a light adhesive to the pre-treated hollow quartz glass tube 1 and the A side of the sapphire glass sheet to form a connector; place the connector in a constant temperature furnace for constant temperature deepening of the light adhesive treatment to obtain a non-magnetic vacuum flange connector.

[0044] The manufacturing method disclosed in this application aims to solve the problem of airtight sealing after welding sapphire glass sheets and non-magnetic metal CF flanges. It provides a method to prevent air leakage after assembling the vacuum chamber following welding. After assembly of the connector and the vacuum chamber, the vacuum level inside the chamber can reach 1×10⁻⁶. -10 Pa, and can achieve non-magnetic CF flange, so that cold atoms will not be affected by magnetism when the vacuum chamber is working, making the cold atom laser more stable when it is working.

[0045] A copper-based metal oxide film is first vacuum brazed and sintered onto the outer surface of the sapphire glass. The coefficient of thermal expansion of sapphire glass is 6.7 × 10⁻⁶. -6 At / ℃, the coefficient of thermal expansion of CT4 titanium alloy is (9.41-10.03) ×10 -6 At ℃, the coefficient of thermal expansion of 316L material is 17.3 × 10⁻⁶. -6 At / ℃, the expansion coefficients of sapphire glass and the two metal materials are close, allowing them to be welded together using brazing technology in the high-temperature vacuum environment of a vacuum brazing furnace. The welded material has good sealing performance and will not leak.

[0046] In some embodiments, after machining a through hole in the center of the sapphire glass plate 2, chamfers are machined on both sides of the hole, and a step adapted to the CF flange 3 is machined on the side that contacts the CF flange 3; the inner wall of the through hole and the chamfers on both sides of the hole are polished until there are no visible pits.

[0047] Further preferably, a copper-based metal oxide film with a thickness of 0.08-0.12 mm is sintered at high temperature on the outer cylindrical surface of the sapphire glass sheet 2, specifically including:

[0048] Apply high-temperature resistant sintering prevention paste evenly to the two connecting surfaces and the stepped circular surface of the sapphire glass plate 2;

[0049] After the high-temperature sintering prevention paste has cured, the sapphire glass plate 2 is placed in a vacuum furnace and heated to 1050-1200℃. A copper-based metal oxide film with a thickness of 0.08-0.12mm is uniformly sintered on the outer surface. The high-temperature sintering prevention paste applied to the sapphire glass plate 2 is then scraped off.

[0050] In some embodiments, the two connecting surfaces at both ends of the sapphire glass sheet 2 are first ground and then polished, with each surface having a thickness of 0.1-0.15 mm removed; the A surface of the sapphire glass sheet is free of scratches under a 20x microscope.

[0051] In some embodiments, the pretreatment of the CF flange 3 specifically involves: machining a flange knife edge on one side of the CF flange 3; and opening a stepped hole on the other side that is compatible with the sapphire glass plate 2.

[0052] More preferably, one connecting surface of the polished sapphire glass sheet 2 contacts the CF flange 3, and the flange-glass sheet is formed by vacuum brazing, specifically including:

[0053] The polished sapphire glass sheet 2 is placed in the stepped hole of the CF flange 3. A ring of amorphous copper solder sheet 4 is placed in the gap between the sapphire glass sheet 2 and the CF flange 3. A layer of oxygen-free copper brazing paste is evenly applied above the gap to form the component to be processed.

[0054] The components to be processed are placed in a vacuum brazing furnace and heated to 630-710℃. Vacuum brazing yields an integrated flange-glass sheet.

[0055] In some embodiments, the pretreatment of the hollow quartz glass tube 1 specifically includes:

[0056] Take a hollow glass tube made of quartz glass, and grind and polish both ends until they meet the requirements for gloss adhesive, requiring aperture N=-0.2 and defect level II; under a 20x microscope, there are no scratches on the entire gloss adhesive surface, and the polished surface is evenly coated with waterproof protective paint.

[0057] In some embodiments, the connector is placed in a constant temperature oven for a temperature of 200-230°C for 4-6 hours to deepen the gloss adhesive treatment.

[0058] In some embodiments, a method for manufacturing a non-magnetic vacuum flange connector includes:

[0059] Step 1: Machining CF flange 3, one side is the flange connection cutting edge, and the other side is a stepped groove with a diameter 0.4mm larger than the outer circle of the sapphire glass sheet and a depth of 3mm;

[0060] Step 2: Machin a through hole in the center of the sapphire glass plate 2, and chamfer the two holes with a 0.5×45° bevel. Polish the inner wall of the through hole and the chamfer on both holes until there are no visible pits.

[0061] Step 3: Place the sapphire glass plate 2 into a vacuum furnace and sinter a copper-based metal oxide film with a thickness of 0.08-0.12mm evenly on the outer surface at high temperature.

[0062] Step 4: Polish both ends of the sapphire glass plate 2. The A side must meet the requirements for glossy adhesive. Under a 20x microscope, no scratches are allowed on the entire glossy adhesive surface.

[0063] Step 5: Polish both ends of the hollow quartz glass tube 1. After polishing, it must meet the requirements of the gloss adhesive. Both sides should have an aperture of N=-0.2 and a defect level of II. Under a 20x microscope, the entire gloss adhesive surface should not have any scratches.

[0064] Step Six: Place the polished and metallized sapphire glass sheet 2 on both sides into the 3mm deep stepped groove of the CF flange 3, positioning it with a 0.5mm deep step. Place a ring of amorphous copper solder sheet in the gap between the sapphire glass sheet 2 and the CF flange 3, and evenly apply a layer of oxygen-free copper brazing paste above the gap. Then, place them together in a vacuum brazing furnace and heat them to 630-710℃. Use the vacuum brazing process to weld the two together, forming an integral flange-glass sheet at the weld seam.

[0065] Step 7: Polish the A-side (without steps) of the sapphire glass sheet again with the integrated flange-glass sheet. The A-side should be free of pitting when viewed under a 20x microscope after polishing, meeting the requirements of the gloss adhesive. The aperture should be N=-0.2, the defect level should be II, and there should be no scratches on the entire gloss adhesive ring.

[0066] Step 8: Apply a light adhesive to one end face of the hollow quartz glass tube 1 onto the polished sapphire glass sheet, aligning the center of the inner hole of the glass tube with the center hole of the sapphire glass sheet.

[0067] Step 9: Place the coated components into a constant temperature oven for further coating treatment, so that the coated components become a whole, forming a set of vacuum flange connectors with non-magnetic metal CF flanges.

[0068] This method utilizes the high material properties of 316L or titanium alloy materials at both high and low temperatures, and their non-magnetic nature. A vacuum brazing process is used to weld 316L or titanium alloy materials and sapphire glass sheets together. After the sapphire glass sheets and hollow quartz glass tube 1 are coated with a light adhesive, a connector that can be used under ultra-high vacuum conditions is formed.

[0069] This set of non-magnetic, high-temperature resistant CF flange connectors for use under ultra-high vacuum conditions comprises three components: a custom-made metal CF flange, a perforated sapphire glass sheet, and a hollow quartz glass tube 1. The metal CF flange and the perforated sapphire glass sheet are welded together using a vacuum brazing process. After polishing, the connecting surfaces of the perforated sapphire glass sheet and the hollow quartz glass tube 1 are first bonded together with a light adhesive, then placed together in a constant-temperature furnace at 200-230℃ for 4-6 hours for a deeper adhesive bonding treatment. After this treatment, the connector is complete. The thermal expansion coefficients of 316L and titanium alloy materials are close to those of sapphire glass. Utilizing the properties of these materials, through multiple experiments, it was found that vacuum brazing can be used to weld them together, resulting in high weld sealing performance. The deeper adhesive bonding treatment significantly improves the connection strength and gas tightness of the sapphire glass and hollow quartz glass tube 1, meeting the requirements for use under ultra-high vacuum conditions, and the baking temperature can reach up to 450℃.

[0070] In some embodiments, taking the CF35 metal flange vacuum connector as an example, the manufacturing process of the CF flange 3 using the CF35 metal flange is as follows:

[0071] Step 1: Select non-magnetic 316L stainless steel or CT4 titanium alloy material, and machine it according to the required dimensions of CF flange 3. One side is a flange knife edge, and the other side is a stepped hole connection surface. The structure of CF flange 3 is as follows: Figure 3As shown, the diameters of the stepped holes, from largest to smallest, are φ37.4, φ35.0, and φ33.0; the step depth of the φ37.4 hole is 2.5 mm; the step depth of the φ35.0 hole is 0.5 mm; and the hole of the φ33.0 hole is a through hole.

[0072] Step 2: Machining a through hole with a diameter of φ18.1 and a step with a diameter of φ35.0 and a depth of 0.65mm in the center of a sapphire glass sheet 2 with a diameter of φ37.0 and a thickness of 4.3mm, with chamfers of 0.55×45° on both outer circles and the hole opening; polishing the inner wall of the φ18.1 hole in the middle and the chamfers on both sides of the hole opening, requiring no pitting visible to the naked eye;

[0073] Step 3: Evenly coat the top and bottom planes and the φ35.0 stepped circular surface of the sapphire glass plate 2 with a layer of...

[0074] Apply a layer of high-temperature sintering prevention paste and let it stand for 4-6 hours until it cures. Then, place the sapphire glass plate 2 in a fixture and put it into a vacuum furnace together. Heat the furnace to 1050-1200℃ and uniformly sinter a copper-based metal oxide film with a thickness of 0.08-0.12mm on the outer surface of the φ37.0 circle. After that, take out the metallized workpiece and scrape off the applied high-temperature sintering prevention paste with a blade.

[0075] Step 4: Grind and polish both sides of the sapphire glass sheet, removing 0.1-0.15mm from each side. The finished workpiece thickness is 4mm. Side B (with steps) and side A (without steps) must be visually inspected under a background light for no pitting. Side A must have an aperture N=-0.2 and a defect level of II. Under a 20x microscope, the entire polished surface must be free of scratches. (The last sentence appears to be incomplete and possibly refers to a different step.) Figure 4 As shown;

[0076] Step 5: Fabricate a hollow quartz glass tube 1 with an outer diameter of φ25mm, an inner diameter of φ18mm, and a length of 80mm. The material is quartz glass. On a chamfering die, chamfer the inner diameter and outer diameter of both ends of the hollow quartz glass tube 1 to 0.55x45°. Vertically clamp the hollow quartz glass tubes 1 into a tray-fixing fixture, 10-12 tubes per tray. First grind, then polish one end face. The grinding and polishing removal amount is 0.2-0.25mm, requiring the material to meet the requirements for glossy adhesive. For a surface with aperture N=-0.2 and defect level II, under a 20x microscope, the entire glossy surface must be free of scratches. Then, evenly apply a waterproof protective varnish to the polished surface. Clamp and grind / polish the other end face using the same method described above, removing 0.2-0.25mm of material. This must meet the requirements for glossy adhesive, with aperture N=-0.2 and defect level II. Under a 20x microscope, the entire glossy surface must be free of scratches. Hollow quartz glass tube 1, as shown... Figure 5 As shown;

[0077] Step Six: Place the polished and metallized sapphire glass sheet (B side) into CF flange 3.

[0078] In a stepped groove with a diameter of φ37.4 mm and a depth of 3 mm, a step with a diameter of φ35 mm and a depth of 0.5 mm is used for positioning to ensure the concentricity of the φ37 outer circle of the sapphire glass sheet 2 and the φ37.4 stepped hole of the CF flange 3, making the gap uniform. A ring of amorphous copper solder with a thickness of 0.1 mm and a height of 3.5 mm is placed in the gap, and a layer of oxygen-free copper brazing paste 4 is evenly applied above the gap. The fabricated components are placed together in a vacuum brazing furnace and heated to 630-710℃. The two are welded together using the vacuum brazing process, forming a single weld. The placement of the sapphire glass sheet, flange, and solder is as follows. Figure 6 As shown;

[0079] Step 7: Polish the sapphire glass A side (without steps) of the component with CF flange 3 and sapphire glass sheet 2 brazed together again. The sapphire glass A side should be free of pitting under a 20x microscope after polishing, meeting the requirements of the gloss adhesive. The aperture should be N=-0.2, the defect level should be II, and there should be no scratches on the gloss adhesive ring of the entire surface.

[0080] Step 8: Apply a light adhesive to one end face of the polished hollow quartz glass tube 1 onto the surface of the sapphire glass sheet A, so that the center of the φ18 inner hole of the glass tube and the center of the φ18.1 through hole of the sapphire glass sheet are roughly aligned.

[0081] Step Nine: Place the bonded connectors from Step Eight into a constant temperature oven and maintain the temperature at 200-230℃ for 4-6 hours for further bond treatment. After this treatment, the connector processing is complete. This makes the bonded components a single unit, forming a vacuum chamber connector with a non-magnetic metal CF flange. The structural diagram of the vacuum chamber connector is shown below. Figure 2 As shown.

[0082] This invention discloses a vacuum chamber connector for a non-magnetic metal CF flange that can be used in ultra-high vacuum environments. One end of the hollow quartz glass tube 1 of the connector is sealed to the perforated surface of the vacuum glass chamber with adhesive, and the other end of the flange is sealed to the vacuum pumping equipment with an oxygen-free copper sealing ring, forming a closed vacuum chamber. After evacuation, the vacuum level inside the chamber can reach 1×10⁻⁶. -10 Pa is used in scientific experiments involving cold atoms in ultra-high vacuum.

[0083] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method of manufacturing a non-magnetic vacuum flange connection, characterized in that, The application relates to a non-magnetic vacuum flange connector. After a circular through hole is processed in the center of a sapphire glass sheet (2), a copper-based metal oxide film with a thickness of 0.08-0.12 mm is high-temperature sintered on the outer cylindrical surface of the sapphire glass sheet (2); two connecting surfaces at the two ends of the sapphire glass sheet (2) are polished to obtain a polished sapphire glass sheet (2); a CF flange (3) and a hollow quartz glass tube (1) are pretreated; one connecting surface of the polished sapphire glass sheet (2) is in contact with the CF flange (3), and vacuum brazing is adopted to form an integrated flange-glass sheet; the other connecting surface is polished to meet the requirements of optical cementing, and a sapphire glass sheet A surface is formed; the pretreated hollow quartz glass tube (1) is optically cemented with the sapphire glass sheet A surface to form a connecting piece; the connecting piece is placed in a constant-temperature furnace for constant-temperature deep optical cementing treatment, and a non-magnetic vacuum flange connecting piece is obtained.

2. The method of claim 1, wherein the non-magnetic vacuum flange connection is made of a non-magnetic material. After a circular through hole is processed in the center of a sapphire glass sheet (2), the two hole openings are chamfered, and the surface in contact with the CF flange (3) is processed into a step matched with the CF flange (3); the inner wall of the circular through hole and the chamfered surfaces of the two hole openings are polished to be free of visual pits.

3. The method of claim 2, wherein the non-magnetic vacuum flange connection is made of a non-magnetic material. A copper-based metal oxide film with a thickness of 0.08-0.12 mm is high-temperature sintered on the outer cylindrical surface of the sapphire glass sheet (2), and the specific process comprises the following steps: uniformly smear high-temperature sintering-resistant paste on the two connecting surfaces and the step surface of the sapphire glass sheet (2); after the high-temperature sintering-resistant paste is solidified, the sapphire glass sheet (2) is placed in a vacuum furnace, and the temperature is heated to 1050-1200 DEG C; a copper-based metal oxide film with a thickness of 0.08-0.12 mm is uniformly high-temperature sintered on the outer surface; and the high-temperature sintering-resistant paste smeared on the sapphire glass sheet (2) is scraped off.

4. The method of claim 1, wherein the non-magnetic vacuum flange connection is made of a non-magnetic material. The two connecting surfaces at the two ends of the sapphire glass sheet (2) are first ground and then polished, and the thickness of each surface is removed by 0.1-0.15 mm; the sapphire glass sheet A surface is free of scratches under a 20-fold microscope.

5. The method of claim 1, wherein the non-magnetic vacuum flange connection is made of a non-magnetic material. The pretreated CF flange (3) is characterized in that one surface of the CF flange (3) is processed into a flange knife opening, and the other surface is processed into a step hole matched with the sapphire glass sheet (2).

6. The method of claim 5, wherein the non-magnetic vacuum flange connection is made of a non-magnetic material. one connecting surface of the polished sapphire glass sheet (2) is in contact with the CF flange (3), and vacuum brazing is adopted to form an integrated flange-glass sheet, and the specific process comprises the following steps: the polished sapphire glass sheet (2) is placed in the step hole of the CF flange (3), a ring of amorphous copper solder (4) is placed in the gap between the sapphire glass sheet (2) and the CF flange (3), a layer of oxygen-free copper brazing paste is uniformly smeared on the gap, and a to-be-processed assembly is formed; the to-be-processed assembly is placed in a vacuum brazing furnace, the temperature is heated to 630-710 DEG C, and an integrated flange-glass sheet is obtained through vacuum brazing.

7. The method of claim 1, wherein the non-magnetic vacuum flange connection is made of a non-magnetic material. The pretreated hollow quartz glass tube (1) comprises the following steps: a hollow glass tube made of quartz glass is taken, and the two end surfaces are first ground and then polished to meet the requirements of optical cementing, the optical circle N=-0.2, and the defect level is grade II; under a 20-fold microscope, the entire optical cementing surface is free of scratches, and the polished surface is uniformly smeared with waterproof protective paint.

8. The method of claim 1, wherein the non-magnetic vacuum flange connection is made of a non-magnetic material. The temperature for the deepening photo-curing treatment of the connecting piece in the constant temperature furnace is 200-230 ℃, and the time is 4-6 hours.

9. A non-magnetic vacuum flange connection, characterized by The non-magnetic vacuum flange connecting piece is prepared by the method of any one of claims 1-8.

10. A non-magnetic vacuum flange connection according to claim 9, characterized in that The CF flange (3) is internally welded with a sapphire glass sheet (2), one end of the sapphire glass sheet (2) is fixedly connected with a hollow quartz glass tube (1), the other end of the hollow quartz glass tube (1) is photo-cured and sealed with a perforated surface of a vacuum glass chamber, one end of the CF flange (3) is connected and sealed with an oxygen-free copper sealing ring of a vacuum pumping device, and a closed vacuum chamber is formed.

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