A lithium aluminum silicon glass for aerospace applications and its preparation process

Abstract

This invention discloses a high-performance lithium aluminum silicon glass for aerospace applications and its preparation process, belonging to the field of glass technology. The lithium aluminum silicon glass composition, based on the mass percentage of the compounds, contains: Al₂O₃ 11.5-12.5%, Li₂O 3-4%, Na₂O 11-11.5%, B₂O₃ 2-3%, Y₂O₃ 2-3%, Ag₂O₃, and... + @ZrO2 2-3%, P2O5 1-1.5%, MgF2 0.3-0.5%, SiO2 balance, the sum of the mass percentages of all components is 100%; the Ag + @ZrO2 is porous zirconium dioxide loaded with silver ions. This invention obtains aluminosilicate glass with high strength, high light transmittance and antibacterial properties by adjusting the composition of lithium aluminosilicate glass raw materials and strengthening process. The four-point bending strength is ≥665MPa, the light transmittance is ≥90.3% and the antibacterial performance is over 98%.

Description

Technical Field

[0001] This invention belongs to the field of glass technology, specifically relating to a lithium aluminum silicon glass for aerospace applications and its preparation process. Background Technology

[0002] As an integral part of aircraft structure, aerospace transparent components must not only meet requirements for optics, environmental adaptability, durability, and fatigue life, but also possess high strength and scratch resistance. Inorganic glass, with its high hardness, excellent optical properties, and stable operation at high temperatures, is an ideal material for manufacturing aerospace transparent components. With technological advancements, research on inorganic glass for aerospace transparent components is moving towards "lightweight and high-strength." Compared to soda-lime silicate glass and sodium aluminum silicate glass, lithium aluminum silicate (LAS) glass, with its higher elastic modulus, can maintain high mechanical strength, impact resistance, and superior scratch resistance even at a thinner thickness. Therefore, LAS glass has become a more ideal inorganic glass material for aerospace transparent components after soda-lime silicate glass and sodium aluminum silicate glass.

[0003] The main components of lithium aluminum silicon glass are SiO2, Al2O3, Li2O, Na2O, ZrO2, etc. Among them, SiO2 is an important oxide that forms the basic glass network structure, and the [SiO4] tetrahedron formed constitutes the basic framework of the glass. Al2O3 is the glass network forging body, which exists in the form of [AlO4] tetrahedron structure and can enhance the degree of polymerization of the glass network. Alkali metal oxides such as Li2O and Na2O mainly serve as glass network modifiers. By introducing non-bridging oxygen, they disrupt the network structure and promote the precipitation of microcrystals.

[0004] Most glass products only undergo cold processing, and their thermal history only includes the process of the original glass gradually cooling from its molten state to room temperature. However, as application scenarios demand increasingly higher glass performance, especially for mass-producible ultra-thin glass, the thinness of the glass leads to weak mechanical properties, making it necessary to strengthen the glass matrix. Ion exchange is one of the most efficient strengthening methods. Placing the glass in a high-temperature molten salt bath, large-particle ions replace small-particle ions in the glass to generate compressive stress, thereby improving the glass's mechanical strength. In chemically strengthened glass systems, compared to sodium aluminosilicate glass and sodium-calcium silicate glass, lithium aluminosilicate glass is a high-strength engineering glass specifically designed for compressive stress storage. The Li₂O in aluminosilicate glass provides small-radius Li₂O for the two-step chemical tempering strengthening process. + The first step is to simultaneously increase the surface compressive stress (CS) and the depth of stress layer (DOL) to ensure that the glass has good mechanical properties; the second step is to reduce the high-temperature viscosity of the glass, promote the full melting of high Al2O3 content, increase the elastic modulus of the glass body, and at the same time reduce the glass density.

[0005] Research has found that the most widely used inorganic antibacterial agents are silver-based metal ion antibacterial agents. Ag + As an antibacterial agent, it is used in the mass production of antibacterial glass via ion exchange. Its main mechanism is through Ag... + Sodium ions (Na) on the glass surface + ) or potassium ions (K + The process involves exchanging silver with Ag to modify the glass surface, improving its mechanical properties while introducing an antibacterial agent into the glass surface. Although silver possesses excellent antibacterial properties, the glass undergoes Ag exchange... + Ag will form on the surface after antibacterial treatment. + Agglomeration causes yellow, patchy spots to appear on the glass, severely affecting its optical properties such as transmittance. Therefore, how to prepare aerospace-grade lithium aluminum silicon glass that combines high light transmittance and antibacterial properties has become an urgent technical problem to be solved. Summary of the Invention

[0006] One objective of this invention is to provide a lithium aluminum silicon glass for aerospace applications, solving the problem that existing lithium aluminum silicon glasses cannot simultaneously achieve high light transmittance and antibacterial properties.

[0007] The second objective of this invention is to provide a process for preparing the aforementioned lithium aluminum silicon glass.

[0008] The objective of this invention can be achieved through the following technical solutions:

[0009] A lithium aluminum silicon glass for aerospace applications, comprising, by mass percentage of the compounds: Al₂O₃ 11.5-12.5%, Li₂O 3-4%, Na₂O 11-11.5%, B₂O₃ 2-3%, Y₂O₃ 2-3%, Ag₂O₃ 2% + @ZrO2 2-3%, P2O5 1-1.5%, MgF2 0.3-0.5%, SiO2 balance, the sum of the mass percentages of each component is 100%.

[0010] As a further technical solution of the present invention, the aerospace-grade lithium aluminum silicon glass comprises, by mass percentage of the compounds: Al₂O₃ 12%, Li₂O 3.5%, Na₂O 11.2%, B₂O₃ 2.5%, Y₂O₃ 2.5%, Ag₂O₃ 2.5%, and Ag₂O₃ 2.5%. + @ZrO2 2%, P2O5 1.5%, MgF2 0.5%, SiO2 balance, the sum of the mass percentages of each component is 100%.

[0011] This invention introduces appropriate Ag into lithium aluminum silicon glass raw materials. + @ZrO2, P2O5, and MgF2 were used as composite nucleating agents, and Ag... +@ZrO2 has the conventional function of promoting the nucleation and crystallization of microcrystalline glass, P2O5 can affect the crystallization of glass by promoting strong phase separation, and MgF2 can promote nucleation through phase separation, thus refining the grain size. The three form a composite nucleating agent and work synergistically to make the glass crystal particles small and the particles in the crystals closely arranged, which enhances the ability of the glass matrix to resist external forces. A large number of glass phase-crystal phase and crystal phase-crystal phase interfaces are formed in the glass system. The presence of these interfaces can change the direction of cracks and play a "pinning effect" to improve the bending strength of the glass. Compared with the use of a single nucleating agent, the grain size is smaller, the grain refinement and strengthening effect is more obvious, and it is more conducive to improving the bending strength of the glass.

[0012] As a further technical solution of the present invention, the Ag + @ZrO2 is a porous zirconium dioxide loaded with silver ions.

[0013] For Ag + When doped into a glass system, Ag is easily reduced to elemental silver, which then aggregates into nanoparticles, coloring the glass and affecting its light transmittance. This invention addresses this issue by using Ag... + Preloaded into the pores of porous zirconium dioxide, equivalent to Ag + It provides a "protective chamber," and the stable zirconium dioxide shell can effectively trap Ag. + It is isolated from external high temperature and reducing environment, which effectively improves Ag + Stability, due to Ag + The glass body was not reduced, and it still retains high light transmittance. During use, Ag... + It can exert its antibacterial effect through ion exchange or diffusion.

[0014] As a further technical solution of the present invention, the Ag + The raw materials for preparing @ZrO2 include porous zirconium dioxide and silver nitrate solution. The ratio of porous zirconium dioxide to silver nitrate solution is 1g:10-20mL, and the concentration of silver nitrate solution is 0.1-1mol / L.

[0015] As a further technical solution of the present invention, the Ag + The preparation steps for ZrO2 are as follows:

[0016] Porous zirconium dioxide was ultrasonically dispersed in deionized water to obtain a mixture. This mixture was then combined with silver nitrate solution and stirred at 20-30°C in the dark for 8-12 hours. After the mixture was dissolved, it was filtered, and the filter cake was washed with deionized water until no free Ag was found in the washing liquid. + Vacuum dried at 40-45℃ to constant weight to obtain Ag + @ZrO2.

[0017] As a further technical solution of the present invention, the ratio of porous zirconium dioxide to deionized water is 1g:10-20mL.

[0018] As a further technical solution of the present invention, the porous zirconium dioxide preparation steps are as follows:

[0019] UiO-66 was placed in a tube furnace and held at 500°C for 2 hours under a nitrogen atmosphere, followed by holding at 500°C for 2 hours under an air atmosphere to obtain porous zirconium dioxide.

[0020] As a further technical solution of the present invention, the heating rate of the tube furnace is 3-10℃ / min.

[0021] As a further technical solution of the present invention, the UiO-66 is a zirconium 1,4-carboxybenzene MOF, a raw material well known to those skilled in the art, which can be prepared by referring to known methods or purchased commercially. UiO-66 is a zirconium-based porous MOF material. It is first carbonized in a nitrogen atmosphere, a process that stabilizes its MOF framework structure; then it is calcined in air. This stepwise calcination method effectively prevents the material structure from collapsing at high temperatures, thus better inheriting the porous characteristics of the precursor UiO-66. Therefore, compared with direct air calcination, the porous zirconium dioxide obtained by this method not only has a larger specific surface area but also a more uniform and porous pore structure.

[0022] The manufacturing process of lithium aluminum silicon glass for aerospace applications includes the following steps:

[0023] S1. Combine Al2O3, Li2O, Na2O, B2O3, Y2O3, Ag + @ZrO2, P2O5, MgF2 and SiO2 are mixed evenly and transferred to a furnace for high-temperature melting to obtain molten glass. The molten glass is then fed into a tin bath through a flow channel for forming, and then annealed to obtain glass blocks.

[0024] S2. The glass block is preheated and then subjected to the first strengthening. After the strengthening is completed, the resulting glass is cooled to room temperature in a heat dissipation furnace to obtain pre-strengthened glass.

[0025] S3. The pre-strengthened glass is preheated and then strengthened a second time. After strengthening, the resulting glass is cooled to room temperature in a heat dissipation furnace to obtain lithium aluminum silicon glass.

[0026] As a further technical solution of the present invention, the high-temperature melting temperature is 1550-1650℃ and the high-temperature melting time is 4-5h.

[0027] As a further technical solution of the present invention, the annealing temperature is 550-600℃, the annealing time is 20-30min, and after the annealing is completed, the furnace is cooled to room temperature.

[0028] As a further technical solution of the present invention, the preheating temperature in S2 and S3 is 360-380℃ and the preheating time is 1-2h.

[0029] As a further technical solution of the present invention, the first strengthening molten salt is a molten liquid of sodium nitrate, the first strengthening temperature is 360-370℃, and the time is 6-8h.

[0030] As a further technical solution of the present invention, the second strengthening molten salt is a mixed molten liquid composed of sodium nitrate and potassium nitrate in a mass ratio of 1-2:8-9, and the second strengthening temperature is 395-420℃, and the time is 2-4h.

[0031] In the glass matrix strengthening process, the first step of this application involves treatment with sodium nitrate molten salt. This step mainly aims to allow the Na... + With Li in glass + Or Na + The first step involves exchanging sodium nitrate to form a preliminary compressive stress layer on the surface. The second step uses a composite molten salt of sodium nitrate and potassium nitrate for final strengthening. Compared to existing strengthening processes, this application uses sodium nitrate in the first step. + With Ag + The exchange driving force is much smaller than K + With Ag + This enhancement method helps protect Ag in the initial enhancement stage. + To prevent excessive replacement, the antibacterial effect of the glass is maintained, and it also serves as a basis for subsequent K... + with Na + This exchange lays the foundation for ensuring the strength and performance of the glass.

[0032] As a further technical solution of the present invention, the initial temperature of the heat dissipation furnace in S2 is 360-370℃, and the initial temperature of the heat dissipation furnace in S3 is 395-420℃.

[0033] The beneficial effects of this invention are:

[0034] 1. This invention obtains aluminosilicate glass with high strength, high light transmittance and antibacterial properties by adjusting the composition of lithium aluminosilicate glass raw materials and strengthening process. The four-point bending strength is ≥665MPa, the light transmittance is ≥90.3%, and the antibacterial performance is over 98%.

[0035] 2. This invention uses Ag + @ZrO2、 O5 and MgF2 are used as composite nucleating agents, and their synergistic effect promotes the formation and crystallization process of lithium aluminum silicon glass. This combination not only refines the grains and enhances the crystal density, but also exerts a "pinning effect" by forming a large number of glass phase-crystal phase and crystal phase-crystal phase interfaces to change the crack propagation path and significantly improve the bending strength of the glass.

[0036] 3. To prevent Ag + The reduction of Ag to elemental silver in glass causes coloring problems; this invention addresses this issue by reducing Ag to elemental silver. + It is pre-loaded inside the pores of porous zirconium dioxide. The structure is Ag. + It provides isolation and protection, ensuring stability in high-temperature and reducing environments, thereby maintaining the glass's high light transmittance. During use, Ag... + It can achieve its antibacterial function through slow release via ion exchange or diffusion.

[0037] 4. In the enhanced treatment, this invention employs a two-step ion exchange process: firstly, preliminary treatment is carried out in sodium nitrate molten salt to allow Na to... + With Li in glass + / Na + Exchange forms a surface compressive stress layer, while avoiding Ag + The Ag was largely displaced; subsequently, a final strengthening process was performed using a composite molten salt of sodium nitrate and potassium nitrate. This stepwise strategy protected the Ag. + To maintain antibacterial properties and also for subsequent K + -Na + The exchange lays the foundation and ensures that the glass ultimately has high strength. Detailed Implementation

[0038] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0039] The following is a detailed description with reference to specific examples.

[0040] Preparation Example 1

[0041] This preparation example provides an Ag + @ZrO2, the preparation steps are as follows:

[0042] 10g of porous zirconium dioxide was ultrasonically dispersed in 100mL of deionized water to obtain a mixture. The mixture was then mixed with 100mL of 0.1mol / L silver nitrate solution and stirred at 20℃ in the dark for 8 hours. After the mixture was dissolved, it was filtered, and the filter cake was washed with deionized water until no free Ag was found in the washing solution.+ Vacuum dried at 40℃ to constant weight to obtain Ag + @ZrO2.

[0043] The preparation steps for porous zirconium dioxide are as follows:

[0044] UiO-66 was placed in a tube furnace and heated to 500℃ at a heating rate of 3℃ / min under a nitrogen atmosphere and held for 2 hours. Then, it was held at 500℃ for 2 hours under an air atmosphere to obtain porous zirconia.

[0045] Preparation Example 2

[0046] This preparation example provides an Ag + @ZrO2, the preparation steps are as follows:

[0047] 10g of porous zirconium dioxide was ultrasonically dispersed in 150mL of deionized water to obtain a mixture. The mixture was then mixed with 150mL of 0.5mol / L silver nitrate solution and stirred at 25℃ in the dark for 10h. After the mixture was dissolved, it was filtered, and the filter cake was washed with deionized water until no free Ag was found in the washing liquid. + Vacuum dried at 42℃ to constant weight to obtain Ag + @ZrO2.

[0048] The preparation steps for porous zirconium dioxide are as follows:

[0049] UiO-66 was placed in a tube furnace and heated to 500℃ for 2 hours at a heating rate of 10℃ / min under a nitrogen atmosphere. Then, it was held at 500℃ for 2 hours under an air atmosphere to obtain porous zirconia.

[0050] Preparation Example 3

[0051] This preparation example provides an Ag + @ZrO2, the preparation steps are as follows:

[0052] 10g of porous zirconium dioxide was ultrasonically dispersed in 200mL of deionized water to obtain a mixture. The mixture was then mixed with 200mL of 1mol / L silver nitrate solution and stirred at 30℃ in the dark for 12h. After the mixture was removed, it was filtered, and the filter cake was washed with deionized water until no free Ag was found in the washing liquid. + Vacuum dried at 45℃ to constant weight to obtain Ag + @ZrO2.

[0053] The preparation steps for porous zirconium dioxide are the same as in Preparation Example 1.

[0054] Example 1

[0055] A lithium aluminum silicon glass for aerospace applications, comprising, by mass percentage of the compounds: Al₂O₃ 11.5%, Li₂O 3%, Na₂O 11%, B₂O₃ 2%, Y₂O₃ 2%, and Ag from Preparation Example 1. + @ZrO2 2%, P2O5 1%, MgF2 0.3%, SiO2 balance, the sum of the mass percentages of each component is 100%.

[0056] The manufacturing process of lithium aluminum silicon glass for aerospace applications includes the following steps:

[0057] S1. Combine Al2O3, Li2O, Na2O, B2O3, Y2O3, Ag + @ZrO2, P2O5, MgF2 and SiO2 are mixed evenly and transferred to a furnace to be melted at 1550℃ for 4 hours to obtain glass liquid. The glass liquid is then fed into a tin bath through a flow channel for forming and annealed at 550℃ for 20 minutes. After the annealing is completed, the glass block is cooled to room temperature in the furnace to obtain glass block.

[0058] S2. The glass block is preheated at 360°C for 1 hour, and then subjected to the first strengthening in molten sodium nitrate at 360°C for 6 hours. After strengthening, the resulting glass is placed in a heat dissipation furnace at an initial temperature of 360°C. The furnace cover is opened, the power is turned off, and the glass is cooled to room temperature with the furnace to obtain the pre-strengthened glass.

[0059] S3. The initially strengthened glass is preheated at 360℃ for 1 hour, and then subjected to a second strengthening. The second strengthening molten salt is a mixed molten liquid composed of sodium nitrate and potassium nitrate in a mass ratio of 1:9. The second strengthening temperature is 395℃ and the time is 2 hours. After strengthening, the obtained glass is placed in a heat dissipation furnace with an initial temperature of 395℃. The heat dissipation furnace cover is opened, the power is turned off, and the glass is cooled to room temperature with the furnace to obtain lithium aluminum silicon glass.

[0060] Example 2

[0061] A lithium aluminum silicon glass for aerospace applications, comprising, by mass percentage of the compounds: Al₂O₃ 12%, Li₂O₃ 3.5%, Na₂O 11.2%, B₂O₃ 2.5%, Y₂O₃ 2.5%, and Ag from Preparation Example 1. + @ZrO2 2%, P2O5 1.5%, MgF2 0.5%, SiO2 balance, the sum of the mass percentages of each component is 100%.

[0062] The preparation process of lithium aluminum silicon glass for aviation is the same as in Example 1.

[0063] Example 3

[0064] A lithium aluminum silicon glass for aerospace applications, comprising, by mass percentage of the compounds: Al₂O₃ 12.5%, Li₂O 4%, Na₂O 11.5%, B₂O₃ 3%, Y₂O₃ 3%, and Ag from Preparation Example 1. + @ZrO2 3%, P2O5 1.5%, MgF2 0.5%, SiO2 balance, the sum of the mass percentages of each component is 100%.

[0065] The preparation process of lithium aluminum silicon glass for aviation is the same as in Example 1.

[0066] Example 4

[0067] An aerospace-grade lithium aluminum silicon glass, differing from Example 1 only in that the "Ag" in Example 1 is removed. + Replace "@ZrO2" with the product obtained in Example 2 by equal mass.

[0068] Example 5

[0069] An aerospace-grade lithium aluminum silicon glass, differing from Example 1 only in that the "Ag" in Example 1 is removed. + Replace "@ZrO2" with the product obtained in Example 3 by equal mass.

[0070] Example 6

[0071] A lithium aluminum silicon glass for aerospace applications differs from Example 1 only in its manufacturing process. The manufacturing process of the lithium aluminum silicon glass for aerospace applications in this example includes the following steps:

[0072] S1. Combine Al2O3, Li2O, Na2O, B2O3, Y2O3, Ag + @ZrO2, P2O5, MgF2 and SiO2 are mixed evenly and transferred to a furnace for high-temperature melting at 1600℃ for 4.5h to obtain glass liquid. The glass liquid is then fed into a tin bath through a flow channel for forming, and then annealed at 580℃ for 25min. After the annealing is completed, the glass is cooled to room temperature in the furnace to obtain glass blocks.

[0073] S2. The glass block is preheated at 370℃ for 1.5 hours, and then subjected to the first strengthening in molten sodium nitrate at 365℃ for 7 hours. After strengthening, the resulting glass is placed in a heat dissipation furnace at an initial temperature of 365℃. The furnace cover is opened, the power is turned off, and the glass is cooled to room temperature with the furnace to obtain the pre-strengthened glass.

[0074] S3. The initially strengthened glass is preheated at 370℃ for 1.5 hours and then subjected to a second strengthening. The second strengthening molten salt is a mixed molten liquid composed of sodium nitrate and potassium nitrate in a mass ratio of 1.5:8.5. The second strengthening temperature is 405℃ and the time is 3 hours. After strengthening, the obtained glass is placed in a heat dissipation furnace with an initial temperature of 405℃. The heat dissipation furnace cover is opened, the power is turned off, and the glass is cooled to room temperature with the furnace to obtain lithium aluminum silicon glass.

[0075] Example 7

[0076] A lithium aluminum silicon glass for aerospace applications differs from Example 1 only in its manufacturing process. The manufacturing process of the lithium aluminum silicon glass for aerospace applications in this example includes the following steps:

[0077] S1. Combine Al2O3, Li2O, Na2O, B2O3, Y2O3, Ag + @ZrO2, P2O5, MgF2 and SiO2 are mixed evenly and transferred to a furnace for high-temperature melting at 1650℃ for 5 hours to obtain glass liquid. The glass liquid is then fed into a tin bath through a flow channel for forming, and then annealed at 600℃ for 30 minutes. After the annealing is completed, the glass is cooled to room temperature in the furnace to obtain glass blocks.

[0078] S2. The glass block is preheated at 380℃ for 2 hours, and then subjected to the first strengthening in molten sodium nitrate at 370℃ for 8 hours. After strengthening, the resulting glass is placed in a heat dissipation furnace at an initial temperature of 370℃. The furnace cover is opened, the power is turned off, and the glass is cooled to room temperature with the furnace to obtain the pre-strengthened glass.

[0079] S3. The initially strengthened glass is preheated at 380℃ for 2 hours and then subjected to a second strengthening. The second strengthening molten salt is a mixed molten liquid composed of sodium nitrate and potassium nitrate in a mass ratio of 2:8. The second strengthening temperature is 420℃ and the time is 4 hours. After strengthening, the resulting glass is placed in a heat dissipation furnace with an initial temperature of 420℃. The furnace cover is opened, the power is turned off, and the glass is cooled to room temperature with the furnace to obtain lithium aluminum silicon glass.

[0080] Example 8

[0081] An aerospace-grade lithium aluminum silicon glass, compared to Example 2, differs only in that the manufacturing process of the aerospace-grade lithium aluminum silicon glass in this example is the same as that in Example 7.

[0082] Comparative Example 1

[0083] An aluminosilicate glass, differing from Example 2 only in that this comparative lithium aluminosilicate glass, by mass percentage of the compounds, contains: Al₂O₃ 12%, Li₂O 3.5%, Na₂O 11.2%, B₂O₃ 2.5%, Y₂O₃ 2.5%, and Ag from Preparation Example 1. + @ZrO2 2.25%, P2O5 1.75%, SiO2 balance, the sum of the mass percentages of each component is 100%.

[0084] Comparative Example 2

[0085] An aluminosilicate glass, differing from Example 2 only in that this comparative lithium aluminosilicate glass, by mass percentage of the compounds, contains: Al₂O₃ 12%, Li₂O 3.5%, Na₂O 11.2%, B₂O₃ 2.5%, Y₂O₃ 2.5%, and Ag from Preparation Example 1. + @ZrO2 2.75%, MgF2 1.25%, SiO2 balance, the sum of the mass percentages of each component is 100%.

[0086] Comparative Example 3

[0087] An aluminosilicate glass, compared to Example 2, differs only in that the comparative lithium aluminosilicate glass contains, by mass percentage of the compounds: Al2O3 12%, Li2O 3.5%, Na2O 11.2%, B2O3 2.5%, Y2O3 2.5%, P2O5 2.5%, MgF2 1.5%, with SiO2 as the balance, and the sum of the mass percentages of each component is 100%.

[0088] Comparative Example 4

[0089] An aluminosilicate glass, differing from Example 2 only in that the Ag in Example 2 is used... + @ZrO2 was replaced with an equal mass of a physical mixture of silver nitrate and ZrO2 in a mass ratio of 10:1.7, which is to add silver nitrate and ZrO2 to a mixer according to the ratio and stir at 200 rpm for 10 min.

[0090] Comparative Example 5

[0091] A lithium aluminum silicon glass, compared with Example 2, differs only in that the phrase "then a first strengthening is carried out in molten sodium nitrate liquid at a strengthening temperature of 360°C for 6 hours, and after strengthening, the resulting glass is placed in a heat dissipation furnace at an initial temperature of 360°C" in the preparation process S2 of Example 2 is replaced with "then a first strengthening is carried out in molten sodium nitrate and potassium nitrate in a mass ratio of 65:100 at a strengthening temperature of 360°C for 6 hours, and after strengthening, the resulting glass is placed in a heat dissipation furnace at an initial temperature of 360°C".

[0092] The lithium aluminum silicon glasses obtained in Examples 1-8 and Comparative Examples 1-5 were subjected to performance tests. The test items and test methods are as follows:

[0093] The four-point bending strength was tested using a CMT6502 microcomputer-controlled electronic universal testing machine with glass dimensions of 150×57×0.55mm, according to ASTM7C158-2002 standard.

[0094] The sample was processed to a thickness of 0.7 mm and polished with the opposite surfaces parallel. The transmittance at 550 nm was measured using a Lambda 950 UV-Vis-NIR spectrophotometer.

[0095] The antibacterial properties of the samples were evaluated using the viable cell count method. The antibacterial rate was calculated as follows: Antibacterial rate = [(Number of surviving colonies in control glass - Number of surviving colonies in antibacterial glass) / Number of surviving colonies in control glass] × 100%. The control glass was ordinary glass without antibacterial properties. The number of colonies was measured according to the relevant requirements of GB 4789.2-2016 National Food Safety Standard for Microbiological Examination of Food - Determination of Total Colony Count, and the antibacterial rate was calculated.

[0096] The test results are shown in Table 1:

[0097] Table 1

[0098]

[0099] As can be seen from the data recorded in Table 1, the lithium aluminum silicon glass obtained in Examples 1-8 has a four-point bending strength ≥665MPa, a light transmittance ≥90.3%, and an antibacterial performance of over 98%, with Example 8 showing the best overall performance.

[0100] The test results from Examples 1, 4, and 5 show that, under the condition that other conditions remain unchanged, the Ag provided by Preparation Examples 1, 2, and 3 is effective. + The performance of lithium aluminum silicon glass prepared using ZrO2 as a raw material is not significantly different, with the best results observed in preparation example 2.

[0101] The test results of Examples 1, 6 and 7 show that, under the condition that other conditions remain unchanged, the lithium aluminum silicon glass obtained by different strengthening processes has different properties;

[0102] As can be seen from the test results in Example 1, Comparative Example 1, Comparative Example 2, and Comparative Example 3, the use of Ag... + @Zr , and Mg As a composite nucleating agent, the synergistic effect of the three agents promotes the formation and crystallization process of lithium aluminum silicon glass, and the effect is better than that of two nucleating agents.

[0103] As can be seen from the test results of Example 1 and Comparative Example 4, under the condition that other conditions remain unchanged, the lithium aluminum silicon glass obtained by using the physical mixture of silver nitrate and zirconium dioxide as raw material has significantly poorer transmittance.

[0104] As can be seen from the test results of Example 1 and Comparative Example 5, changing the molten salt used in the first strengthening process, while keeping other conditions unchanged, will result in a significantly poorer antibacterial performance of lithium aluminum silicon glass.

[0105] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0106] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A process for producing a lithium aluminosilicate glass for aircraft use for producing a lithium aluminosilicate glass for aircraft use, characterized by, The lithium aluminum silicon glass composition contains, in mass percent of compounds: Al203 11.5-12.5%, Li20 3-4%, Na20 11-11.5%, B203 2-3%, Y203 2-3%, Ag + @ZrO2 2-3%, P2O5 1-1.5%, MgF2 0.3-0.5%, SiO2 the balance, the sum of the mass percentages of the components being 100%. The preparation process of the lithium aluminum silicon glass for aviation comprises the following steps: S1, Al2O3, Li2O, Na2O, B2O3, Y2O3, Ag + @ZrO2, P2O5, MgF2and SiO2are mixed uniformly, transferred to a kiln for high temperature melting to obtain a glass liquid, the glass liquid is formed into a tin bath through a flow channel, and then annealing treatment is performed to obtain a glass block; S2, preheating the glass block to perform the first strengthening, and after the first strengthening, cooling the obtained glass to room temperature in a heat dissipation furnace to obtain a preliminarily strengthened glass; S3, preheating the preliminarily strengthened glass to perform the second strengthening, and after the second strengthening, cooling the obtained glass to room temperature in a heat dissipation furnace to obtain the lithium aluminum silicon glass; The first strengthening molten salt is a molten liquid of sodium nitrate, the first strengthening temperature is 360-370 DEG C, and the time is 6-8h; The Ag + @ZrO2 is a porous zirconium dioxide on which silver ions are supported.

2. The process for preparing lithium aluminosilicate glass for aerospace applications according to claim 1, characterized in that, The lithium-aluminum-silicon glass for aviation contains, in terms of mass percentage of compounds, Al2O3 12%, Li2O 3.5%, Na2O 11.2%, B2O3 2.5%, Y2O3 2.5%, Ag + @ZrO2 2%, P2O5 1.5%, MgF2 0.5%, SiO2 the balance, the sum of the mass percentages of the components being 100%.

3. The process for preparing lithium aluminosilicate glass for aerospace applications as claimed in claim 1 wherein, The Ag + The raw materials for preparing the Ag@ZrO2 include porous zirconium dioxide and silver nitrate solution, the amount ratio of the porous zirconium dioxide and the silver nitrate solution is 1 g:10-20 mL, and the concentration of the silver nitrate solution is 0.1-1 mol / L.

4. The process for preparing lithium aluminosilicate glass for aerospace applications as claimed in claim 1 wherein, The Ag + The preparation procedure of the @ZrO2 is as follows: The porous zirconium dioxide is ultrasonically dispersed in deionized water to obtain a mixed solution, the mixed solution and a silver nitrate solution are mixed, stirred at 20-30 °C for 8-12 h in the dark, after the end, suction filtration, the filter cake is washed with deionized water until there is no free Ag + in the washing liquid, vacuum drying at 40-45 °C until the constant weight to obtain Ag + @ZrO2.

5. The process for preparing a lithium aluminosilicate glass for aerospace applications according to claim 1 or 4, characterized in that, The preparation steps of the porous zirconium dioxide are as follows: The UiO-66 is placed in a tube furnace, and under a nitrogen atmosphere, heat preservation is carried out at 500 DEG C for 2h, and then under an air atmosphere, heat preservation is carried out at 500 DEG C for 2h to obtain the porous zirconium dioxide.

6. The process for preparing lithium aluminosilicate glass for aerospace applications as claimed in claim 1 wherein, The preheating temperature in S2 and S3 is 360-380 DEG C, and the preheating time is 1-2h.

7. The process for preparing lithium aluminosilicate glass for aerospace applications as claimed in claim 1 wherein, The second strengthening molten salt is a mixed molten liquid composed of sodium nitrate and potassium nitrate in a mass ratio of 1-2:8-9, the second strengthening temperature is 395-420 DEG C, and the time is 2-4h.

8. A lithium aluminosilicate glass for aerospace applications, characterized in that, The lithium aluminum silicon glass for aviation is prepared by the preparation process in any one of claims 1-7.

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