Edge-covering glass for micro-channel plate, preparation method of edge-covering glass and micro-channel plate

Abstract

The invention relates to edge-covered glass for a micro-channel plate, a preparation method of the edge-covered glass and the micro-channel plate, and belongs to the field of glass for micro-channel plates. The composition for the edge-covering glass for the micro-channel plate comprises the following raw materials in percentage by mass of oxides: 52-70% of SiO2; 4 to 6 percent of Al2O3; 1 to 3% of Y2O3; 4 to 6 percent of K2O; 2 to 4 percent of Na2O; the sum of the contents of the Nb2O5 and the MoO3 is 14 to 22 percent; the sum of the content of MgO and the content of CaO is 5-8%. Specific components are selected, and the ratio of the components is adjusted, so that the edge-covered glass has a relatively strong framework, the bending strength is greater than or equal to 70MPa, the transformation temperature Tg is greater than or equal to 650 DEG C, the softening temperature Tf is greater than or equal to 710 DEG C, and the thermal expansion coefficient is 75-80 * 10 <-7 > / DEG C; and the glass is better matched with third-generation leather glass. The obtained micro-channel plate is not deformed or damaged after being prepared in a whole process.

Description

Technical Field

[0001] This invention belongs to the field of glass for microchannel plates, and in particular relates to a edging glass for microchannel plates, its preparation method, and the microchannel plate itself. Background Technology

[0002] Microchannel plates (MCPs) are excellent two-dimensional electron multiplier materials with high gain, high spatial resolution, and high temporal resolution. They also have advantages such as small size, light weight, and low operating voltage. They are the core materials for extremely weak photodetectors such as image intensifiers, photomultiplier tubes, and photon counters, and have very important applications in high-energy physics, X-ray diagnosis and treatment, space exploration, low-light night vision, and nuclear detection.

[0003] The core technology of current mainstream microchannel plate (MSP) fabrication is glass multifiber drawing. In this process, a poorly soluble acid-containing outer glass tube and a matching acid-soluble core glass rod are drawn together at high temperature into single glass fibers. These single fibers are then bundled to form multifibers, and several multifibers are bundled together, fitted with an outer sheath of glass, fused at high temperature, and then cut into sheets. The core glass is then removed by acid etching, forming an MCP microporous array structure. Hydrogen reduction and electrode deposition complete the entire process of microchannel plate fabrication. The existing fabrication process dictates that the thermal and mechanical properties of the sheath and the outer glass must be matched. This matching ensures that the microchannel plate does not deform during the entire production process, maintaining its flatness, and thus guaranteeing the mechanical strength, resolution, and uniformity of the two-dimensional electronic image.

[0004] To further improve the signal-to-noise ratio and resolution of MCPs, third-generation MCP cladding glasses with low noise and high secondary electron emission coefficients have been developed. Compared to second-generation MCP cladding glasses, third-generation MCP cladding glasses have achieved significant improvements in thermodynamic properties, with a marked increase in transition temperature and softening temperature. Specifically, the transition temperature (T0) is significantly lower. g The temperature reaches over 620℃, and the softening temperature reaches 680℃ (T). f The thermodynamic expansion coefficient is 65*10. -7 / K. Based on the thermodynamic compatibility principle of MCP skin glass and edge-sealing glass, the transition temperature T for edge-sealing glass adapted to third-generation MCP is determined. g ≥650℃, softening temperature T f Temperature should be ≥710℃, and the coefficient of thermodynamic expansion should be ≥75×10. -7 / K.

[0005] The pore size of third-generation microchannel plates (MCPs) is typically below 4 μm. To maintain their electron multiplication properties, the thickness of the MCP must be reduced while decreasing the pore size to achieve the optimal aspect ratio. The thickness of third-generation MCPs has been reduced to below 0.22 mm. However, such a thinness severely reduces their mechanical strength, making them highly susceptible to damage during handling. Even slight external forces can cause MCPs to crack or deform during production, assembly, and use. They are also prone to deformation during high-temperature heat treatment, as high temperatures reduce the viscosity of the glass material, leading to deformation under its own weight or external stress. Furthermore, the softening temperature of the edging material should be higher than the operating temperature range of the MCP, especially the baking temperature during vacuum degassing, to ensure stable performance and prevent softening deformation under high-temperature conditions. However, edging glasses prepared using existing technologies have a transition temperature below 550°C and a softening temperature below 600°C, and their insufficient strength leads to reliability issues. Therefore, developing high-strength edging glasses compatible with third-generation MCP edging glasses is a hot research topic in this field. Summary of the Invention

[0006] The main objective of this invention is to provide a microchannel plate edge-sealing glass that is compatible with the third-generation microchannel plate skin glass.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A composition for edge-sealing glass for microchannel plates comprises, by mass percentage of oxides: 52-70% SiO2; 4-6% Al2O3; 1-3% Y2O3; 4-6% K2O; 2-4% Na2O; the sum of Nb2O5 and MoO3 is 14-22%; and the sum of MgO and CaO is 5-8%.

[0008] Furthermore, it also includes Sb2O3, wherein the amount of Sb2O3 is 0.5 to 2% of the total mass of the raw materials.

[0009] The sum of the contents of SiO2 and Al2O3 is m1; the sum of the contents of Nb2O5 and MoO3 is m2; wherein, m1:m2 is 3~5.5:1.

[0010] The mass ratio of Nb2O5 to MoO3 is 5~10:1; the amount of Sb2O3 used is 0.5~1% of the total mass of the raw materials.

[0011] This invention also provides a method for preparing edge-sealing glass for microchannel plates using the aforementioned composition, comprising the following steps: S1: Raw material mixing: Mix raw materials based on the mass percentage of oxides to prepare a compound feed; S2: Melt, clarify and homogenize the batch material to obtain molten glass; S3: Cool the molten glass to 1200~1300℃, and then perform casting, rough annealing and precision annealing treatments in sequence to obtain a glass rod with edging; S4 Finished Product Preparation: The edge-sealing glass rod is subjected to optical grinding and polishing processes to obtain edge-sealing glass for preparing microchannel plates.

[0012] The S2 melting temperature is 1400~1550℃, and the melting time is 6~8h. The high-temperature melting temperature and time are limited to a reasonable range. Under the premise of ensuring that the batch material is heated and melted at high temperature and that the raw materials are completely melted, the lowest possible melting temperature and the shortest melting time are used to improve efficiency.

[0013] During the rough annealing process, the annealing temperature is 600~700℃ and the holding time is 3~6h. The precision annealing includes: heating to 550-650℃ at a rate of 2.5-4.0℃ / min, holding at that temperature for 3-5.5 hours, and then cooling to room temperature at a rate of 0.5-1.5℃ / h; The room temperature is 20~25℃.

[0014] The present invention also provides a edging glass for a microchannel plate, which is prepared according to the preparation method described above.

[0015] The present invention further provides a microchannel plate, comprising a sheath glass, a core glass, and a cladding glass for the microchannel plate, wherein the sheath glass has a transition temperature T. g ≥620℃, softening temperature T f The coefficient of thermal expansion is 67×10 at temperatures ≥680℃ and 20~300℃. -7 / ℃~72×10 -7 / ℃.

[0016] The transition temperature T of the edge-sealed glass g ≥650℃; softening temperature T f The coefficient of thermal expansion is 75×10 at temperatures ≥710℃ and 20~300℃. -7 / ℃~80×10 -7 / ℃; The transition temperature of the edge-mounted glass is 30-40°C higher than that of the outer glass, and the softening temperature of the edge-mounted glass is 30-45°C higher than that of the outer glass. The difference between the coefficient of thermal expansion of the edge-mounted glass and the coefficient of thermal expansion of the outer glass is 5 × 10⁻⁶. -7 / ℃~10×10 -7 / ℃.

[0017] The components of the aforementioned glass, by mass percentage, include the following: 35-45% PbO and Bi2O3, 20-40% SiO2, 10-16% BaO and MgO, 5-12% Cs2O and Rb2O, 0.5-5% CaO, 1-4% Al2O3, 3-7% ZrO and Nb2O5, and 5-10% SrO.

[0018] By employing the above technical solution, the present invention has at least the following advantages: 1. This invention provides a cladding glass for microchannel plates and its preparation method. By selecting specific components and adjusting the ratio between the components, the cladding glass has a strong skeleton and a bending strength of ≥70MPa, with a transition temperature T0. g ≥650℃, softening temperature T f ≥710℃, coefficient of thermal expansion 75~80×10 -7 / ℃; better matched with third-generation leather glass. Furthermore, the edge-sealed glass of this invention has excellent anti-crystallization properties; the acid resistance stability of the edge-sealed glass sample was tested using the national standard GB / T 7962.14 test method for colorless optical glass, and its level was Class 1.

[0019] 2. The present invention also provides a microchannel plate, comprising a core glass, a sheath glass, and an edge-sealing glass, wherein the edge-sealing glass has a transition temperature T. g ≥650℃, softening temperature T f ≥710℃, and an expansion coefficient of 75~80×10 that matches the glass material. -7 / ℃, Glass transition temperature of the leather g ≥620℃, softening temperature T f The coefficient of thermal expansion is 67–72 × 10⁻⁶ at temperatures ≥680℃ and 20–300℃. -7 The microchannel plate obtained at / ℃ did not deform or break after the entire process. Its outer diameter was 20-30mm, its thickness was 0.20~0.22mm, and its end face flatness was ≤15μm.

[0020] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, the preferred embodiments of the present invention are described in detail below. Detailed Implementation

[0021] To further illustrate the technical means and effects adopted by the present invention to achieve its intended purpose, the specific implementation methods, structures, features, and effects of the present invention are described in detail below with reference to preferred embodiments. In the following description, different "embodiments" or "embodiments" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics in one or more embodiments can be combined in any suitable form.

[0022] The components of the cladding glass used in microchannel plates typically consist of: a glass framework oxide, a glass network oxide that adjusts viscosity, thermal and chemical stability, and improves material properties, and oxides that enhance flexural strength. The interactions among these components collectively determine the glass's various properties. Therefore, to significantly improve the transition temperature and softening temperature of the cladding glass, making it compatible with the high softening temperature cladding glass used in third-generation MCPs, this invention increases the doping content of Al2O3, an oxide with a high softening point, in the glass composition, and adds oxides such as Nb2O5 and MoO3 to enhance heat resistance and mechanical strength. Simultaneously, to enhance the flexural strength of the glass, this invention adds a small amount of Y2O3 to the glass composition. However, this invention has found that controlling the composition of the glass framework structure and the doped oxides with high heat resistance and improved mechanical strength—specifically, the sum of the masses of SiO2 and Al2O3 (m1) and Nb2O5 and MoO3 (m2)—and strictly controlling the ratio of m1 to m2 within a certain range, is beneficial to improving the anti-crystallization performance, stability, and weather resistance of the edging glass. This invention further discovers that glass is quite sensitive to the doping content of MoO3. To maintain the glass-forming properties, basic thermal and chemical stability of the edging glass, the proportion of MoO3 doped in the glass composition should be maintained with that of Nb2O5 to significantly improve its heat resistance and mechanical strength while ensuring the basic properties of the glass. Based on the above, appropriately adjusting the content of the glass framework structure oxides and other network oxides ensures that the properties of the obtained edging glass are suitable for the third-generation MCP (Metal-Oxide-Chip) cladding glass. The technical solution of this invention is formed based on the above inventive concept.

[0023] In this invention, SiO2 is a crucial component forming the basic framework structure of the edging glass. This invention limits the SiO2 mass percentage in the glass to 52-70% to maintain the glass's strength, chemical stability, viscosity, and coefficient of thermal expansion. If the SiO2 mass percentage in the glass is below 52%, the glass's chemical stability will deteriorate; conversely, if the SiO2 mass percentage is above 70%, the glass's viscosity will increase, and the coefficient of thermal expansion will be too low, significantly increasing the difficulty of glass melting and molding, and also making the edging glass incompatible with the third-generation MCP (Medium-Density Composite) glass.

[0024] K₂O and Na₂O are oxides on the glass network that readily migrate and diffuse within the glass, reducing its high-temperature viscosity and making it easier to melt. They can also alter and control the glass's coefficient of thermal expansion. However, excessive amounts of either can reduce the glass's chemical stability and strength. Therefore, the K₂O content is controlled at 4%–6%, and the Na₂O content at 2%–4%. Nb₂O₅ and MoO₃ are glass structure-regulating oxides. Appropriately increasing their content in this edging glass system can improve the heat resistance temperature of the edging glass; furthermore, they are also the main oxides for controlling the mechanical strength of the glass. This invention preferably limits the mass percentage of Nb₂O₅ and MoO₃ in the edging glass to 14-22%. When the total mass percentage of Nb₂O₅ and MoO₃ in the edging glass exceeds 22%, it reduces the chemical and structural stability of the edging glass, and significantly reduces its resistance to crystallization. When the total mass percentage of Nb₂O₅ and MoO₃ in the edging glass is less than 14%, it significantly reduces the mechanical strength of the edging glass, making the third-generation microchannel plate prone to cracking or deformation during fabrication, especially under its own weight or external stress during high-temperature heat treatment. Preferably, in some embodiments, the present invention strictly limits the mass ratio of Nb2O5 to MoO3 in the edging glass to 5~10:1. This ensures the stability of the glass's thermal and chemical properties while maintaining its strength. Adding too much MoO3 can cause an imbalance in the glass's internal structure, break the internal network structure, and worsen the glass-forming performance, leading to the ceramization of the edging glass, which is detrimental to the stability of the edging glass.

[0025] MgO and CaO are oxides in the glass network and also fluxes in glass. Limiting their mass percentage in edge-sealed glass to 5-8% can prolong the forming process of edge-sealed glass and is beneficial to the forming operation and thermal processing performance of glass. However, if the total content of MgO and CaO is less than 5%, it will significantly increase the difficulty of melting and forming edge-sealed glass.

[0026] Al2O3 is a structurally modulating oxide for edge-sealing glass. Its mass percentage in edge-sealing glass significantly affects the coefficient of thermal expansion, transition temperature, and softening temperature. If its mass percentage in edge-sealing glass is higher than 6%, it will lead to enhanced glass network bonding and a significant increase in high-temperature viscosity, making the glass material more difficult to melt and form. However, if the mass percentage of Al2O3 in edge-sealing glass is lower than 4%, the transition temperature and softening temperature of the edge-sealing glass will not match those of the third-generation microchannel plate sheet glass.

[0027] Y2O3 is an oxide in the glass network. In this invention, the mass percentage of Y2O3 in the edge-sealed glass is preferably limited to 1-3%. Under this condition, the bending strength of the edge-sealed glass can be increased to more than 70 MPa, and it has suitable high-temperature viscosity and softening temperature. However, if too much is added, the glass-forming properties will deteriorate and phase separation will occur.

[0028] Preferably, the sum of the mass percentages of SiO2 and Al2O3 in the edge-sealed glass of the present invention is denoted as m1, and the sum of the mass percentages of Nb2O5 and MoO3 in the edge-sealed glass is denoted as m2. The ratio of m1 to m2 is 3~5.5:1. Under this condition, the anti-crystallization performance of the edge-sealed glass can be prevented from decreasing, and the glass transition temperature and softening temperature can be prevented from failing to meet the design requirements.

[0029] Preferably, the edge-sealed glass of the present invention further includes a clarifying agent, wherein the clarifying agent is Sb₂O₃. In some embodiments, the content of the clarifying agent is preferably 0.5-1%. The addition of a clarifying agent to the glass composition in the present invention is to facilitate the clarification and homogenization of the molten glass during the preparation process. Furthermore, the Sb³ / Sb 5 ⁺ can act as an "intermediate" ion in the glass network construction, filling weak links in the Si-O network and inhibiting network relaxation caused by the migration of easily migrating ions, thus indirectly improving the bending strength. Strictly limiting the content of the clarifying agent is crucial to ensure complete overflow of bubbles in the edge-sealed glass while simultaneously improving its bending strength and preventing residual or secondary bubbles.

[0030] In the melting, clarifying, and homogenizing process of this invention, the batch material is added to a crucible for melting, clarifying, and homogenizing. The melting temperature is 1400~1550℃, and the melting time is 6~8 hours. The high-temperature melting temperature and time are limited to a reasonable range. While ensuring the batch material is heated and melted at high temperatures, and that the raw materials are completely melted, the lowest possible melting temperature and shortest melting time are used to improve efficiency. The crucible and stirring rod need to have corrosion resistance to avoid corrosion by the molten glass affecting the glass's properties. A crucible made of pure platinum (Pt) or a platinum alloy is used. The platinum alloy is either a platinum-tungsten alloy (with a tungsten mass percentage ≤5%) or a platinum-ytterbium alloy (with a ytterbium mass percentage ≤5%).

[0031] In the molding and annealing steps of this invention, a technical solution of first rough annealing and then precision annealing is adopted. The prepared edge-sealed glass is conducive to the release of internal stress, avoiding the reduction of mechanical strength of MCP due to the release of internal stress in the glass material during the preparation process, which would make it easy to break and affect the service life and reliability of the microchannel plate. At the same time, this annealing scheme can ensure the stability of its electrical properties, thereby improving the stability and accuracy of the microchannel plate operation.

[0032] In the rough annealing process described in this invention, the annealing temperature is 600~700℃ and held for 3~6 hours; the precision annealing includes: heating to 550~650℃ at 2.5~4.0℃ / min, holding for 3~5.5 hours, and then cooling to room temperature at 0.5~1.5℃ / h.

[0033] This invention strictly limits the process parameters of coarse annealing and precision annealing, which helps to better eliminate stress in the glass and improve the mechanical strength of the glass; it also helps to avoid problems such as edge cracking and edge chipping caused by the release of internal stress in the edge-sealed glass during the preparation of MCP.

[0034] Unless otherwise specified, all materials and reagents mentioned below are commercially available products well known to those skilled in the art; unless otherwise specified, all methods described are methods known in the art. Unless otherwise defined, the technical or scientific terms used should have the ordinary meaning understood by those skilled in the art to which this invention pertains.

[0035] In the embodiments and comparative examples of the present invention, the raw material corresponding to Al2O3 is aluminum hydroxide or aluminum oxide; both the raw materials providing each functional component can be the oxides themselves, or the corresponding carbonates or nitrates.

[0036] The testing methods for various performance indicators in the embodiments and comparative examples of this invention are as follows: Transition temperature T g and softening temperature T f Test: According to GB / T 7962.16-2010 Test Method for Colorless Optical Glass; Thermal expansion coefficient test: Tested according to GB / T 7962.16-2010 Test Method for Colorless Optical Glass; Anti-crystallization performance test: The crystallization and phase separation of the edge-sealed glass were observed and tested at 750~1100℃.

[0037] Acid resistance stability test: Tested according to GB / T 7962.14 Colorless optical glass test - Acid resistance stability test method.

[0038] Bending strength: Tested in accordance with GB / T 6569.

[0039] Table 1 Chemical composition and properties of edge-sealing glass for microchannel plates in examples Note: In Tables 1, 2, and 3, A represents the coefficient of thermal expansion of the edge-sealed glass at 300℃, in units of ×10⁻¹⁰. -7 / ℃; B indicates the acid resistance stability of the edge-sealed glass; C indicates the glass transition temperature T of the edge-sealed glass. g The unit is °C; D represents the softening temperature T of the glazing glass. fThe unit is ℃; E represents resistance to crystallization; F represents flexural strength, in MPa.

[0040] In Tables 1 and 3, G represents the coefficient of thermal expansion of the glass at 300℃, with units of ×10⁻¹⁰. -7 / ℃; H represents the glass transition temperature T of the glass. g The unit is °C; I represents the softening temperature T of the glass. f The unit is ℃.

[0041] Table 2 Chemical composition and properties of edge-sealed glass for microchannel plates (comparative examples) Table 3 shows the chemical composition and properties of the glass sheets corresponding to Examples 1-7. As can be seen from the test data in Tables 1 and 2, the edge-sealing glass for microchannel plates prepared by this invention has excellent anti-crystallization properties, high bending strength, and high thermodynamic compatibility with the third-generation microchannel plate sheath glass. As shown in Examples 1 to 7, the performance of the third-generation microchannel plate sheath glass of this invention meets the transition temperature T. g ≥620℃, preferably 620~650℃, softening temperature T f ≥680℃, preferably 680~700℃, with a coefficient of thermal expansion of 70×10 at 20~300℃. -7 / ℃~75×10 -7 / ℃ The glass cladding was tested. In Comparative Example 1, the content of the clarifying agent Sb2O3 was reduced to 0.2%, resulting in a large number of bubbles in the prepared cladding glass rod, and its bending strength was 65MPa, less than 70MPa, which did not meet the requirements. In Comparative Example 2, the absence of Y2O3 significantly reduced the bending strength of the cladding glass to only 59MPa, and the prepared microchannel plate exhibited a large number of breaks and deformations, failing to meet the requirements. In Comparative Example 3, the content of Nb2O5 was reduced to 9%, and the content of MoO3 was reduced to 2.5%, because (SiO2+A The ratio of (l2O3) / (Nb2O5+MoO3) is not in the range of 3~5.5, resulting in poor anti-crystallization properties of the glass, which brings certain difficulties to the wire drawing process. At the same time, it leads to poor heat resistance of the edge-sealing glass, resulting in a large number of breakages and deformations during the subsequent hydrogen reduction process, making it difficult to successfully prepare the corresponding microchannel plate. In Comparative Example 4, the proportion of Al2O3 was reduced to 1%, which caused the expansion coefficient, transition temperature and softening temperature of the edge-sealing glass to not meet the requirements, making it unable to match the third-generation skin glass and unable to prepare the corresponding microchannel plate.

[0042] In Table 3, the components of the outer glass and the corresponding edging glass in each embodiment are only preferred combinations, provided that the transition temperature of the edging glass is 30-40°C higher than that of the outer glass, the softening temperature of the edging glass is 30-45°C higher than that of the outer glass, and the difference between the thermal expansion coefficients of the edging glass and the outer glass is 5 × 10⁻⁶. -7 / ℃~10×10 -7 All types of glass with a temperature of / ℃ can be adapted to the edge-sealing glass of this invention.

[0043] The present invention will be further described below through specific embodiments: Example 1 A method for preparing edge-sealed glass for microchannel plates includes the following steps: S1: Mix the raw materials according to the raw material ratio in Example 1 in Table 1 to prepare the compound; S2: Add the batch material prepared in S1 into a pure platinum (Pt) crucible and melt it at 1450℃ for 6-8 hours to obtain glass melt. During the melting, clarifying and homogenizing process, stir continuously with a stirring rod. S3: Cool the homogenized glass melt from S2 to 1250℃ and pour it into a mold for shaping. After pouring, perform rough annealing and precision annealing in sequence to obtain a glass rod with edging. The rough annealing temperature is 650℃ and held for 4 hours. The precision annealing is: heating to 600℃ at 3℃ / min, holding for 4 hours, and then cooling to room temperature (20℃) at 1℃ / h.

[0044] S4 Finished Product Preparation: The edge-sealing glass rod prepared in S3 is processed through optical grinding, polishing and other steps to obtain the finished edge-sealing glass for preparing MCP.

[0045] Example 2 A method for preparing edge-sealed glass for microchannel plates includes the following steps: S1: Mix the raw materials according to the raw material ratio in Example 1 in Table 1 to prepare the compound; S2: Add the batch material prepared in S1 into a pure platinum (Pt) crucible and melt it at 1550℃ for 6-8 hours to obtain glass melt. During the melting, clarifying and homogenizing process, stir continuously with a stirring rod. S3: Cool the homogenized glass melt from S2 to 1200℃ and pour it into a mold for shaping. After pouring, perform rough annealing and precision annealing in sequence to obtain a glass rod with edging. The rough annealing temperature is 600℃ and held for 5 hours. The precision annealing is as follows: heat up to 550℃ at 2.5℃ / min, hold for 3 hours, and then cool down to room temperature (25℃) at 0.5℃ / h.

[0046] S4 Finished Product Preparation: The edge-sealing glass rod prepared in S3 is processed through optical grinding, polishing and other steps to obtain the finished edge-sealing glass for preparing MCP.

[0047] Example 3 A method for preparing edge-sealed glass for microchannel plates includes the following steps: S1: Mix the raw materials according to the raw material ratio in Example 1 in Table 1 to prepare the compound; S2: Add the batch material prepared in S1 into a pure platinum (Pt) crucible and melt it at 1400℃ for 6-8 hours to obtain glass melt. During the melting, clarifying and homogenizing process, stir continuously with a stirring rod. S3: Cool the homogenized glass melt from S2 to 1300℃ and pour it into a mold for shaping. After pouring, perform rough annealing and precision annealing in sequence to obtain a glass rod with edging. The rough annealing temperature is 700℃ and held for 6 hours. The precision annealing is as follows: heat up to 650℃ at 4.0℃ / min, hold for 5.5 hours, and then cool down to room temperature (25℃) at 1.5℃ / h.

[0048] S4 Finished Product Preparation: The edge-sealing glass rod prepared in S3 is processed through optical grinding, polishing and other steps to obtain the finished edge-sealing glass for preparing MCP.

[0049] Example 4 A method for preparing edge-sealed glass for microchannel plates includes the following steps: S1: Mix the raw materials according to the raw material ratio in Example 1 in Table 1 to prepare the compound; S2: Add the batch material prepared in S1 into a pure platinum (Pt) crucible and melt it at 1500℃ for 6-8 hours to obtain glass melt. During the melting, clarifying and homogenizing process, stir continuously with a stirring rod. S3: Cool the homogenized glass melt from S2 to 1280℃ and pour it into a mold for shaping. After pouring, perform rough annealing and precision annealing in sequence to obtain a glass rod with edging. The rough annealing temperature is 630℃ and held for 3 hours. The precision annealing is as follows: heat up to 680℃ at 3.5℃ / min, hold for 3.5 hours, and then cool down to room temperature (24℃) at 1.2℃ / h.

[0050] S4 Finished Product Preparation: The edge-sealing glass rod prepared in S3 is processed through optical grinding, polishing and other steps to obtain the finished edge-sealing glass for preparing MCP.

[0051] Example 5 The preparation method of the edge-sealing glass for the microchannel plate is the same as that of Example 1, and the raw materials used are those of Example 5 in Table 1.

[0052] Example 6 The preparation method of the edge-sealing glass for the microchannel plate is the same as that of Example 1, and the raw materials used are those of Example 6 in Table 1.

[0053] Example 7 The preparation method of the edge-sealing glass for the microchannel plate is the same as that of Example 1, and the raw materials used are those of Example 7 in Table 1.

[0054] Comparative Example 1 The preparation method of the edge-sealing glass for the microchannel plate is the same as that of Example 1, and the raw materials used are Comparative Example 1 in Table 2.

[0055] Comparative Example 2 The preparation method of the edge-sealing glass for the microchannel plate is the same as that of Example 1, and the raw materials used are Comparative Example 2 in Table 2.

[0056] Comparative Example 3 The preparation method of the edge-sealing glass for the microchannel plate is the same as that of Example 1, and the raw materials used are Comparative Example 3 in Table 2.

[0057] Comparative Example 4 The preparation method of the edge-sealing glass for the microchannel plate is the same as that of Example 1, and the raw materials used are Comparative Example 4 in Table 2.

[0058] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A composition for edge-sealing glass for microchannel plates, characterized in that: The raw materials, based on the mass percentage of oxides, include: 52-70% SiO2; 4-6% Al2O3; 1-3% Y2O3; 4-6% K2O; 2-4% Na2O; the sum of Nb2O5 and MoO3 is 14-22%; and the sum of MgO and CaO is 5-8%.

2. The composition according to claim 1, characterized in that, It also includes Sb2O3, wherein the amount of Sb2O3 is 0.5 to 2% of the total mass of the raw materials.

3. The edge-sealing glass for the microchannel plate according to claim 2, characterized in that, The sum of the contents of SiO2 and Al2O3 is m1; the sum of the contents of Nb2O5 and MoO3 is m2; Where m1:m2 is 3~5.5:

1.

4. The composition according to claim 3, characterized in that, The mass ratio of Nb2O5 to MoO3 is 5~10:1; the amount of Sb2O3 used is 0.5~2% of the total mass of the raw materials.

5. A method for preparing edge-sealing glass for microchannel plates using the composition according to any one of claims 1-4, characterized in that, Includes the following steps: S1: Raw material mixing: Mix raw materials based on the mass percentage of oxides to prepare a compound feed; S2: Melt, clarify and homogenize the batch material to obtain molten glass; S3: Cool the molten glass to 1200~1300℃, and then perform casting, rough annealing and precision annealing treatments in sequence to obtain a glass rod with edging; S4 Finished Product Preparation: The edge-sealing glass rod is subjected to optical grinding and polishing processes to obtain edge-sealing glass for preparing microchannel plates.

6. The preparation method according to claim 5, characterized in that, The S2 is melted at a temperature of 1400~1550℃ for 6~8 hours. During the rough annealing process, the annealing temperature is 600~700℃ and the holding time is 3~6h. The precision annealing includes: heating to 550-650℃ at a rate of 2.5-4.0℃ / min, holding at that temperature for 3-5.5 hours, and then cooling to room temperature at a rate of 0.5-1.5℃ / h; The room temperature is 20~25℃.

7. A type of edge-sealed glass for a microchannel plate, characterized in that, It is prepared according to the preparation method according to any one of claims 5-6.

8. A microchannel plate, characterized in that, Includes a sheath glass, a core glass, and the edge-sealing glass for microchannel plates as described in claim 8, wherein the sheath glass has a transition temperature T. g ≥620℃, softening temperature T f The coefficient of thermal expansion is 70×10⁻⁶ at temperatures ≥680℃ and 20~300℃. -7 / ℃~75×10 -7 / ℃; The transition temperature T of the edge-sealed glass g ≥650℃; softening temperature T f The coefficient of thermal expansion is 75×10 at temperatures ≥710℃ and 20~300℃. -7 / ℃~80×10 -7 / ℃.

9. The microchannel plate according to claim 8, characterized in that, The transition temperature of the edge-mounted glass is 30-40°C higher than that of the outer glass, and the softening temperature of the edge-mounted glass is 30-45°C higher than that of the outer glass. The difference between the coefficient of thermal expansion of the edge-mounted glass and the coefficient of thermal expansion of the outer glass is 5 × 10⁻⁶. -7 / ℃~10×10 -7 / ℃.

10. The microchannel plate according to claim 8 or 9, characterized in that, The components of the aforementioned glass, by mass percentage, include the following: 35-45% PbO and Bi2O3, 20-40% SiO2, 10-16% BaO and MgO, 5-12% Cs2O and Rb2O, 0.5-5% CaO, 1-4% Al2O3, 3-7% ZrO and Nb2O5, and 5-10% SrO.

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