Lithium-aluminum-silicon glass suitable for float electric boosting

Abstract

The invention discloses lithium-aluminum-silicon glass suitable for float electric boosting, and belongs to the technical field of glass manufacturing. According to the glass prepared in the invention, through raw material selection and fine raw material ratio, the performance of each material is fully exerted, side effects caused by excessive use of each raw material are greatly weakened, and compared with glass produced by a traditional float method, the glass has the advantages of high strength, good mechanical properties and high high-temperature resistivity; according to the invention, a float glass electric boosting technology is utilized, and electric boosting heating is used during float glass production, so that the required energy consumption is greatly reduced, the defects of the glass are reduced, and the glass is clearer; in conclusion, the method has important application value in the technical field of glass manufacturing.

Description

Technical Field

[0001] The present invention belongs to the technical field of glass manufacturing, and specifically, relates to a lithium aluminosilicate glass suitable for electro-assisted melting in the float process. Background Art

[0002] With the development of the aerospace industry, glass is increasingly frequently used as aviation transparent components such as aircraft windshields, ventilation windows, and rear observation windows. In view of the high requirements of aerospace glass for strength and impact resistance, lithium aluminosilicate glass is the best choice for aerospace transparent components due to its high strength and ease of subsequent strengthening treatment. In order to meet the requirements of high strengthening of aerospace glass, a lithium aluminosilicate formulation with a high content of Al 2 O 3 is generally used. However, while a high aluminum content increases the glass elastic modulus, it also results in a relatively high viscosity and melting temperature. Currently, electro-assisted melting has become the main heating method. This means that electric energy plays an increasingly important role in the glass melting process. Increasing the high-temperature resistivity of the glass will effectively reduce the process difficulty and energy consumption during melting. A lithium aluminosilicate glass suitable for float production and having high strength introduced in this patent not only has good mechanical properties but also has a relatively high high-temperature resistivity, ensuring the melting efficiency of the glass and energy conservation. Summary of the Invention

[0003] The purpose of the present invention is to overcome the defects of the prior art and provide a lithium aluminosilicate glass suitable for electro-assisted melting in the float process.

[0004] The purpose of the present invention can be achieved by the following technical solutions:

[0005] A lithium aluminosilicate glass suitable for electro-assisted melting in the float process, comprising raw materials in the following weight percentages: SiO 2 : 55 - 65%, Al 2 O 3 : 15 - 20%, B 2 O 3 : 0 - 5%, MgO: 2 - 6%, Na 2 O: 5 - 12%, K 2 O: 2 - 8%, Li 2 O: 2 - 4%, ZrO 2 : 0.5 - 1.5%, TiO 2 : 1 - 2%.

[0006] Further, the weight ratio between the raw materials satisfies the following conditions: (SiO 2 +B 2 O 3 ) ≤ 65%; 10% ≤ (Li 2 O + Na 2 O + K 2O) ≤ 17%; 1% ≤ (ZrO 2 + TiO 2 ) ≤ 3%.

[0007] Furthermore, the raw materials also include 0.2 wt% of CeO 2 , as a fining agent.

[0008] Furthermore, as a preferred technical solution of the present invention, a lithium aluminosilicate glass suitable for float electric boosting melting comprises raw materials in the following weight percentages: SiO 2 : 60 - 63%, Al 2 O 3 : 18.5 - 20%, B 2 O 3 : 0 - 3%, MgO: 2 - 5%, Na 2 O: 5 - 8%, K 2 O: 2 - 5%, Li 2 O: 2.5 - 3.5%, ZrO 2 : 0.5 - 1%, TiO 2 : 1 - 1.5%.

[0009] Adding SiO 2 as the framework for glass formation in the raw materials can enhance the network structure of the glass, making the movement of ions more difficult therein, thereby increasing the resistivity;

[0010] Adding Al 2 O 3 in the raw materials can increase the Young's modulus, inhibit the phase separation of the glass, reduce the thermal expansion coefficient, and increase the strain point;

[0011] Adding B 2 O 3 in the raw materials can participate in the formation of the glass network structure, connect with the silicon - oxygen network, making the glass structure more stable; increase the low - temperature viscosity of the glass and reduce the high - temperature viscosity, preventing the glass from crystallizing;

[0012] Adding Na 2 O and K 2 O in the raw materials, as alkali metals, can provide extra oxygen ions in the glass, break the network of the main network - forming body silicon to form non - bridging oxygen, and are also fluxing agents for making glass, which have a great influence on both the formation of the glass and the fining process of the glass melt;

[0013] Adding MgO in the raw materials, as an alkaline earth metal oxide, it can reduce the high - temperature viscosity of the glass melt and increase the high - temperature resistance of the glass melt, and can also significantly increase the Young's modulus of the glass;

[0014] Adding Li 2 O, Li2 O is a strong flux that can significantly reduce the melting temperature of glass. It can form strong chemical bonds with other ions in the glass network, thereby strengthening the glass network structure, improving the strength and hardness of the glass. At the same time, lithium ions have high ionic activity and can promote the ion exchange of glass;

[0015] Adding ZrO to the raw materials 2 , during the ion exchange process of glass, it can increase the components of the compressive stress on the glass surface, improve the glass hardness and Young's modulus, form strong chemical bonds with oxygen ions in the glass, and block the ion migration channels, thereby increasing the resistivity;

[0016] Adding TiO to the raw materials 2 , its function can improve the chemical stability, thermodynamic properties and ultraviolet absorption properties of the glass. The Ti 4+ ions can enter the glass network structure and change the structure and chemical bond properties of the glass;

[0017] Using CeO 2 as a fining agent, CeO 2 has a relatively high oxidation potential. During the glass melting process, it can quickly remove the gas components in the glass melt and convert them into gas substances that are easier to escape from the glass melt to achieve the clarification effect; and Ce 4+ as a large field strength cation can also enhance the high-temperature resistance of the glass melt.

[0018] Furthermore, a lithium aluminosilicate glass suitable for electro-assisted melting in the float process is prepared by the following steps:

[0019] A1. Put all raw materials into a mixer and mix them evenly to obtain a glass batch;

[0020] A2. Transfer the glass batch obtained in step A1 to a float glass melting furnace, turn on the furnace heating system by electricity, heat it to the melting of the glass, and utilize the resistance of the glass melt to generate Joule heat to strengthen the melting and obtain a molten glass melt;

[0021] A3. Clarify and homogenize the molten glass melt obtained in step A2, then flow it into a tin bath, and introduce a protective gas to carry out float forming. After forming, anneal it and cool it to room temperature with the furnace, and obtain a lithium aluminosilicate glass suitable for electro-assisted melting in the float process through cutting, grinding and polishing.

[0022] Furthermore, the temperature of the heating system in step A2 is 1500 - 1600 °C.

[0023] Furthermore, the protective gas in step A3 is a mixed gas of nitrogen and hydrogen.

[0024] The high temperature promoted by electro-assisted melting can facilitate the floating and bursting of bubbles in the glass melt, significantly reducing the defects of the glass. Moreover, the glass has a high resistivity at high temperatures, requiring less energy consumption. Through the float forming process, the glass has higher transparency and is clearer.

[0025] Advantages of the present invention:

[0026] 1. For the glass prepared by the present invention, through the selection of raw materials and precise raw material ratio, the performance of each material is fully exerted, and the side effects caused by excessive use of each raw material are greatly reduced. Compared with the glass produced by the traditional float process, it has high strength, good mechanical properties, and a high resistivity at high temperatures.

[0027] 2. The present invention utilizes the electro-assisted melting technology for float glass. During the production of float glass, electro-assisted melting heating is used, greatly reducing the required energy consumption, reducing the defects of the glass, and making the glass clearer. In summary, the present invention has important application value in the field of glass manufacturing technology. Specific embodiments

[0028] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present invention.

[0029] A lithium aluminosilicate glass suitable for electro-assisted melting in the float process is prepared through the following steps:

[0030] A1. Put all the raw materials into a mixer and mix them evenly to obtain a glass batch.

[0031] A2. Transfer the glass batch obtained in step A1 to a float glass melting furnace, turn on the furnace heating system by electricity, the temperature is 1500 °C, and then use the resistance of the glass melt to generate Joule heat to strengthen melting, obtaining a molten glass melt.

[0032] A3. Clarify and homogenize the molten glass melt obtained in step A2 in a clarifying tank, then flow it into a tin bath, and introduce a mixed gas of nitrogen and hydrogen (96% nitrogen and 4% hydrogen) as a protective gas for float forming. After forming, anneal it and cool it to room temperature with the furnace, and obtain the lithium aluminosilicate glass suitable for electro-assisted melting in the float process through cutting, grinding, and polishing.

[0033] According to the above experimental steps and controlling the dosage of the raw materials, Examples 1-5 are obtained, and the dosages of Examples 1-5 are shown in Table 1:

[0034] Table 1

[0035]

[0036]

[0037] Comparative Example 1

[0038] Glass produced by using commercially available float process was used.

[0039] The performance tests were carried out on Examples 1 - 5 and Comparative Example 1, and the measured results are shown in Table 2:

[0040] Table 2

[0041]

[0042] As can be seen from Table 2, through the selection of raw materials and the precise ratio of raw materials for the glass prepared in the present invention, the performance of each material is fully exerted, so that the glass prepared in the examples of the present invention has greater hardness, mechanical properties and resistivity than those of the comparative example. Therefore, the present invention has important application value in the field of glass manufacturing technology.

[0043] In the description of the specification, the descriptions referring to the terms "one embodiment", "example", "specific example", etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0044] The above content is only an example and illustration of the present invention. Those skilled in the art of this technology can make various modifications or supplements to the described specific embodiments or use similar methods to replace them, as long as they do not deviate from the invention or exceed the scope defined by the claims of the present invention, they should fall within the protection scope of the present invention.

Claims

1. A lithium aluminosilicate glass suitable for float electric fluxing, characterized in that: The raw materials include the following weight percentages: SiO2: 55-65%, Al2O3: 15-20%, B2O3: 0-5%, MgO: 2-6%, Na2O: 5-12%, K2O: 2-8%, Li2O: 2-4%, ZrO2: 0.5-1.5%, TiO2: 1-2%.

2. The lithium aluminosilicate glass suitable for float electric fluxing according to claim 1, characterized in that: The weight ratio of the raw materials meets the following conditions: (SiO2+B2O3)≤65%; 10%≤(Li2O+Na2O+K2O)≤17%; 1%≤(ZrO2+TiO2)≤3%.

3. The lithium aluminosilicate glass suitable for float electric fluxing according to claim 1, characterized in that: The raw material also includes 0.2 wt% CeO2 as a clarifier.

4. The lithium aluminosilicate glass suitable for float electric fluxing according to claim 1, characterized in that: Prepared by the following steps: A1. Put all raw materials into a mixer and mix them evenly to obtain glass batch; A2, transferring the glass batch obtained in step A1 to a float glass melting furnace, powering on the furnace heating system, utilizing the resistance of the glass liquid to generate Joule heat, intensifying the melting, and obtaining molten glass liquid; A3. The molten glass liquid obtained in step A2 is clarified and homogenized in a clarification tank, and then flows into a tin bath, and a protective gas is introduced to perform float forming. After forming, it is annealed, cooled to room temperature with the furnace, and cut, ground and polished to obtain lithium aluminum silicon glass suitable for float electric fluxing.

5. The lithium aluminosilicate glass suitable for float electric fluxing according to claim 4, characterized in that: The temperature of the heating system in step A2 is 1500-1600°C.

6. The lithium aluminosilicate glass suitable for float electric fluxing according to claim 4, characterized in that: In step A3, the protective gas is a mixed gas of nitrogen and hydrogen.

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