Composition for microcrystalline material, microcrystalline glass, preparation method of microcrystalline glass and electronic equipment

Abstract

The invention relates to a composition for a microcrystalline material, microcrystalline glass, a preparation method of the microcrystalline glass and electronic equipment, and relates to the technical field of inorganic glass. The mass of each component of the composition accounts for the following percentage of the total mass of the composition: 68.2-78.5% of SiO2; 5.0 to 10.5 percent of Al2O3 (aluminum oxide); 10.3 to 18.7% of an alkali metal oxide; 5.0 to 13.4% of a nucleating agent; the alkali metal oxide includes Li2O. According to the composition for the microcrystalline material, the alkali metal oxide Li2O is added, and the proportion of all the components is controlled, so that the microcrystalline glass has relatively high ion exchange depth, and the microcrystalline glass prepared from the composition for the microcrystalline material has excellent anti-falling performance.

Description

Technical Field

[0001] The present disclosure relates to the technical field of inorganic glass, and in particular to a composition for microcrystalline materials, microcrystalline glass and a preparation method thereof, and electronic equipment. Background Art

[0002] With the development of communication technology, mobile phones are used more and more frequently in life. At present, Lithium Aluminum Silicate Glass, as a high-performance glass material that has been chemically strengthened, is widely used in front cover protective glass, back panel, etc. of mobile phones because of its excellent scratch resistance and other properties. Although the surface of Lithium Aluminum Silicate Glass has been chemically strengthened and its mechanical properties have been improved, it is still difficult to meet the requirements for glass drop resistance when it is used in terminal devices such as mobile phones. Therefore, it is necessary to develop a glass product with excellent drop resistance. Summary of the invention

[0003] In order to overcome the problems existing in the related art, the present disclosure provides a composition for microcrystalline materials, microcrystalline glass and a preparation method thereof, and an electronic device.

[0004] According to a first aspect of an embodiment of the present disclosure, a composition for a microcrystalline material is provided.

[0005] The percentage of the mass of each component of the composition to the total mass of the composition is expressed as follows:

[0006] SiO2: 68.2-78.5%; Al2O3: 5.0-10.5%; Alkali metal oxide: 10.3-18.7%; Nucleating agent: 5.0-13.4%;

[0007] The alkali metal oxide includes Li2O.

[0008] In some embodiments of the present disclosure, the alkali metal oxide further includes other alkali metal oxides, and the mass of the Li2O accounts for 73.3-99.6% of the total mass of the alkali metal oxides.

[0009] In some embodiments of the present disclosure, the other alkali metal oxides include one or both of Na2O and K2O.

[0010] In some embodiments of the present disclosure, the nucleating agent includes ZrO2 and P2O5, the mass of ZrO2 accounts for 4.0-8.7% of the total mass of the raw materials of the microcrystalline glass, and the mass of P2O5 accounts for 1.0-4.7% of the total mass of the raw materials of the microcrystalline glass.

[0011] In some embodiments of the present disclosure, the mass ratio of the ZrO2 to the P2O5 is 2.1-2.5:1.

[0012] In some embodiments of the present disclosure, the composition further comprises at least one of the following components:

[0013] CaO: 0-1.2%; MgO: 0-1.2%; SrO: 0-2.5%; BaO: 0-2.3%; ZnO: 0-2.4%; dopant: 0-2.6%; clarifier: 0-1.3%.

[0014] In some embodiments of the present disclosure, the dopant includes one or more of La2O3, Y2O3, and Ta2O5.

[0015] According to a second aspect of an embodiment of the present disclosure, a microcrystalline glass is provided, wherein the microcrystalline glass is prepared from the composition for microcrystalline materials as described above, and the microcrystalline glass includes a first crystalline phase and a second crystalline phase, wherein the first crystalline phase includes lithium disilicate; and the second crystalline phase includes one or more of petalite, lithium metasilicate, zirconium oxide, and lithium phosphate.

[0016] In some embodiments of the present disclosure, the clarifier includes one or more of Sb2O3, SnO2, SnO, and CeO2.

[0017] In some embodiments of the present disclosure, the glass-ceramics includes a strengthening layer located on at least one surface, and the depth of the strengthening layer is 100-150 μm.

[0018] According to a third aspect of an embodiment of the present disclosure, a method for preparing glass-ceramics is provided, the method comprising:

[0019] Melting and molding the microcrystalline material composition under a first preset condition to obtain a matrix glass;

[0020] heat-treating the mother glass under a second preset condition to obtain the glass-ceramics;

[0021] The percentage of the mass of each component of the microcrystalline material composition to the total mass of the microcrystalline material composition is expressed as follows:

[0022] SiO2: 68.2-78.5%; Al2O3: 5.0-10.5%; Alkali metal oxide: 10.3-18.7%; Nucleating agent: 5.0-13.4%;

[0023] The alkali metal oxide includes Li2O.

[0024] According to a fourth aspect of an embodiment of the present disclosure, an electronic device is provided, comprising a cover plate and a shell, wherein the material of the cover plate and / or the shell is microcrystalline glass prepared from the composition for microcrystalline materials as described above, or microcrystalline glass as described above, or microcrystalline glass prepared by the method for preparing microcrystalline glass as described above.

[0025] The technical solution provided by the embodiments of the present disclosure may have the following beneficial effects:

[0026] The present invention can achieve a higher ion exchange depth by adding alkali metal oxide Li2O and controlling the ratio of each component, and the microcrystalline glass prepared from the microcrystalline material composition has excellent anti-drop performance.

[0027] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0029] Figure 1 is a schematic flow chart of a method for preparing glass-ceramics according to an exemplary embodiment;

[0030] Figure 2 is an XRD test diagram shown according to Example 1;

[0031] Figure 3 This is a stress test diagram according to Example 2. DETAILED DESCRIPTION

[0032] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present disclosure. Instead, they are merely examples of devices and methods consistent with some aspects of the present disclosure as detailed in the appended claims.

[0033] Glass-ceramics, also known as glass ceramics, is an inorganic non-metallic material prepared by controlling the glass crystallization process. It consists of at least one functional crystalline phase and residual glass. Glass-ceramics can replace high-strength glass because it has the excellent properties of both glass and ceramics. It can be used in covers and shells of electronic devices such as mobile phones. Although compared with high-strength glass, glass-ceramics has a certain improvement in drop resistance, it still has problems such as shallow ion exchange depth and low bending strength, which limit the application of glass-ceramics.

[0034] In order to solve the above technical problems, the present disclosure provides a composition for microcrystalline materials, wherein the mass percentage of each component of the composition to the total mass of the composition is expressed as follows: SiO2: 68.2-78.5%; Al2O3: 5.0-10.5%; alkali metal oxide: 10.3-18.7%; nucleating agent: 5.0-13.4%; alkali metal oxide includes Li2O. By adding alkali metal oxide Li2O and controlling the proportion of each component, a higher ion exchange depth can be achieved, and the microcrystalline glass prepared from the composition for microcrystalline materials has excellent anti-drop performance.

[0035] An exemplary embodiment of the present disclosure provides a composition for microcrystalline materials, wherein the mass percentage of each component of the composition to the total mass of the composition is expressed as follows: SiO2: 68.2-78.5%; Al2O3: 5.0-10.5%; alkali metal oxide: 10.3-18.7%; nucleating agent: 5.0-13.4%; wherein the alkali metal oxide includes Li2O.

[0036] In this embodiment, by adding alkali metal oxide Li2O and controlling the ratio of each component, a higher ion exchange depth can be achieved, and the microcrystalline glass prepared from the microcrystalline material composition has excellent anti-drop performance.

[0037] SiO2 (silicon dioxide) is an important glass-forming oxide. It forms an irregular continuous network with the structural unit of silicon-oxygen tetrahedron, becomes the skeleton of glass, and is also a necessary component that can become a crystalline phase through the heat treatment of the original glass. If the amount of SiO2 is too low, the resulting glass cannot obtain the corresponding crystalline phase and crystallinity, and the glass structure network cannot reach the ideal stable structure. If the amount of SiO2 is too high, the viscosity of the system will be too high during the preparation process, affecting the processing performance. Therefore, in this embodiment, the amount of SiO2 is controlled at 68.2-78.5%, so that the microcrystalline glass can maintain better comprehensive performance. Exemplarily, the amount of SiO2 is 68.2%, 71.0%, 74.0%, 76.3%, and 78.5%. The amount of SiO2 can also be any amount between the exemplary amounts, for example, the amount of SiO2 can also be any amount between 71.0-74.0%.

[0038] Al2O3 (aluminum oxide) is also a component that can form a glass network structure. It is an important component that helps stabilize the glass structure and improve chemical durability. It can also further improve the thermal conductivity of the glass. It is also a necessary component that can become a crystalline phase through the heat treatment of the original glass. If the amount of Al2O3 is too low, it is difficult to achieve better performance of the microcrystalline glass; due to the high melting point of Al2O3, if the amount of Al2O3 is too high, the melting and devitrification resistance of the microcrystalline glass will deteriorate. At the same time, since Al2O3 is one of the components that form petalite crystals, when the microcrystalline glass contains more petalite crystals, the content of lithium disilicate crystals therein will be reduced, resulting in a decrease in the mechanical strength of the microcrystalline glass. Therefore, in this embodiment, the amount of Al2O3 is controlled at 5.0-10.5%, which can enable the microcrystalline glass to maintain better comprehensive performance. Exemplarily, the amount of Al2O3 is 5.0%, 6.0%, 7.2%, 8.0%, and 10.5%. The amount of Al2O3 may also be any amount between the exemplary amounts, for example, the amount of Al2O3 may also be any amount between 6.0-8.0%.

[0039] Alkali metal oxides are important components for improving the low-temperature melting and formability of glass, and can become necessary components required for the crystal phase composition through heat treatment of the original glass. Among them, alkali metal oxides include Li2O (lithium oxide). When the glass is chemically tempered by ion exchange, Li2O also helps to form a deeper compressive stress layer. In this embodiment, the amount of alkali metal oxide is controlled at 10.3-18.7%, which can enable the microcrystalline glass to maintain better comprehensive properties. Exemplarily, the amount of alkali metal oxide is 10.3%, 13.5%, 15.0%, 17.0%, and 18.7%. The amount of alkali metal oxide can also be any amount between the exemplary amounts, for example, the amount of alkali metal oxide can also be any amount between 13.0-15.0%.

[0040] Nucleating agents can accelerate the crystallization process of glass-ceramics, and help it form a uniformly dispersed microcrystalline phase in a shorter time, thereby improving the mechanical properties and chemical stability of the material; and, nucleating agents can affect the growth rate and size of grains; by controlling the amount of nucleating agents, the size of the grains, the type of crystalline phases, and the relative content can be adjusted, thereby affecting the final performance of the glass-ceramics. In this embodiment, the amount of nucleating agent is controlled at 5.0-13.4%, which can enable the glass-ceramics to maintain better comprehensive performance. Exemplarily, the amount of nucleating agent is 5.0%, 7.7%, 11.0%, and 13.4%. The amount of nucleating agent can also be any amount between the exemplary amounts, for example, the amount of nucleating agent can also be any amount between 5.0-11.0%.

[0041] For example, in one embodiment, the percentage of the mass of each component of the composition to the total mass of the composition is expressed as follows:

[0042] SiO2: 68.2%; Al2O3: 5.0%; alkali metal oxide: 18.7%; nucleating agent: 8.1%; wherein the alkali metal oxide includes Li2O.

[0043] In another embodiment, the percentage of the mass of each component of the composition to the total mass of the composition is expressed as follows:

[0044] SiO2: 69.3%; Al2O3: 7.0%; alkali metal oxide: 10.3%; nucleating agent: 13.4%; wherein the alkali metal oxide includes Li2O.

[0045] In another embodiment, the percentage of the mass of each component of the composition to the total mass of the composition is expressed as follows:

[0046] SiO2: 71.3%; Al2O3: 5.0%; alkali metal oxide: 18.7%; nucleating agent: 5.0%; wherein the alkali metal oxide includes Li2O.

[0047] In another embodiment, the percentage of the mass of each component of the composition to the total mass of the composition is expressed as follows:

[0048] SiO2: 69.0%; Al2O3: 10.5%; alkali metal oxide: 13.0%; nucleating agent: 7.5%; wherein the alkali metal oxide includes Li2O.

[0049] In another embodiment, the percentage of the mass of each component of the composition to the total mass of the composition is expressed as follows:

[0050] SiO2: 78.5%; Al2O3: 5.2%; alkali metal oxide: 10.3%; nucleating agent: 6.0%; wherein the alkali metal oxide includes Li2O.

[0051] In an exemplary embodiment, the alkali metal oxide further includes other alkali metal oxides, and the mass of Li2O accounts for 73.3-99.6% of the total mass of the alkali metal oxides.

[0052] In Li2O-Al2O3-SiO2 (LAS) glass-ceramics, Li2O can significantly reduce the thermal expansion coefficient of glass-ceramics, improve the thermal stability and mechanical properties of glass-ceramics; by controlling the amount of Li2O, it helps to form smaller and more evenly distributed crystals, thereby improving the overall performance of the material. Exemplarily, the mass of Li2O accounts for 73.3%, 80.5%, 86.8%, 90.1%, 96.3%, and 99.6% of the total mass of the alkali metal oxide. The ratio of the mass of Li2O to the total mass of the alkali metal oxide can also be any ratio between the exemplary ratios. For example, the ratio of the mass of Li2O to the total mass of the alkali metal oxide can also be any ratio between 80.5-90.1%.

[0053] In an exemplary embodiment, the other alkali metal oxides include one or both of Na2O and K2O.

[0054] The addition of Na2O (sodium oxide) can improve the chemical stability and thermal stability of glass, help reduce the melting temperature of glass, and promote the melting and flow of glass; the addition of K2O (potassium oxide) can change the growth rate, grain size and crystal phase composition of crystals in microcrystalline glass, thereby affecting the final performance of the material. Na2O and K2O can be used as network modifiers to promote the melting and flow of glass by destroying the glass network structure and reducing the melting temperature and viscosity of glass, which helps the crystallization and ion exchange process of glass. In this embodiment, the other alkali metal oxide can also be one of Na2O and K2O, or a mass ratio of 1.2-3.0:1 of Na2O and K2O can be used for compounding.

[0055] In an exemplary embodiment, the nucleating agent includes ZrO2 and P2O5, the mass percentage of ZrO2 to the total mass percentage of the raw materials of the microcrystalline glass is 4.4-8.7%, and the mass percentage of P2O5 to the total mass percentage of the raw materials of the microcrystalline glass is 1.0-4.7%.

[0056] ZrO2 (zirconium oxide) and P2O5 (phosphorus pentoxide) can act as nucleating agents in glass-ceramics, and can become necessary components of the crystalline phase through heat treatment of the original glass. ZrO2 can help reduce the size of petalite crystals, which is very important for the formation of transparent glass-ceramics. In addition, ZrO2 has a certain effect of reducing the upper limit of the crystallization temperature during molding, which is convenient for better molding. However, due to the high melting point of ZrO2, when its addition ratio is high, it will affect the normal melting of the glass; therefore, in this embodiment, the mass of ZrO2 is controlled to be 4.0-8.7% of the total mass of raw materials of glass-ceramics, so that the glass-ceramics can maintain better performance. Exemplarily, the mass of ZrO2 can be 4.0%, 6.6%, 7.0%, and 8.7% of the total mass of raw materials of glass-ceramics. The ratio of the mass of ZrO2 to the total mass of the raw materials of the microcrystalline glass can also be any ratio between the exemplary ratios. For example, the ratio of the mass of ZrO2 to the total mass of the raw materials of the microcrystalline glass is 4.0-7.0%.

[0057] P2O5 can improve the dispersion coefficient, UV transmittance and light transmittance, but if the amount of P2O5 is too high, it is easy to reduce the resistance to devitrification and phase separation of the glass; however, if the amount of P2O5 is too high, it is easy to reduce the resistance to devitrification and phase separation of the glass; therefore, in this embodiment, the mass percentage of P2O5 to the total mass of the raw materials of the microcrystalline glass is controlled to be 1.0-4.7%, so that the microcrystalline glass can maintain better performance. Exemplarily, the mass percentage of P2O5 to the total mass of the raw materials of the microcrystalline glass can be 1.0%, 2.5%, 3.3%, 4.0%, 4.7%. The ratio of the mass of P2O5 to the total mass of the raw materials of the microcrystalline glass can also be any ratio between the exemplary ratios, for example, the ratio of the mass of P2O5 to the total mass of the raw materials of the microcrystalline glass can also be any ratio between 1.0-4.0%.

[0058] In an exemplary embodiment, the mass ratio of ZrO2 to P2O5 is 2.1-2.5:1.

[0059] In this embodiment, by controlling the mass ratio of ZrO2 to P2O5 to 2.1-2.5:1, the size of the grains can be controlled and the mechanical properties of the microcrystalline glass can be improved. Exemplarily, the mass ratio of ZrO2 to P2O5 is 2.1:1, 2.2:1, 2.4:1, and 2.5:1. The mass ratio of ZrO2 to P2O5 can also be any ratio between the exemplary mass ratios, for example, the mass ratio of ZrO2 to P2O5 can also be any ratio between 2.2-2.4:1.

[0060] In an exemplary embodiment, the composition further comprises at least one of the following components:

[0061] CaO: 0-1.2%; MgO: 0-1.2%; SrO: 0-2.5%; BaO: 0-2.3%; ZnO: 0-2.4%; dopant: 0-2.6%; clarifier: 0-1.3%.

[0062] In this embodiment, other components may be added to the composition to further improve the performance of the glass-ceramics prepared from the composition.

[0063] CaO (calcium oxide) is a network exosome that can accelerate the melting and clarification process of glass and improve the chemical stability of glass; at high temperatures, it can reduce the viscosity of glass liquid to improve the process performance of glass. A small amount of CaO can increase the mechanical strength of glass, but when the amount of CaO is too high, it will increase the tendency of crystallization and cause the glass to become more brittle. Therefore, when the amount of CaO is 0-1.2%, it is beneficial to improve the comprehensive properties of glass. Exemplarily, the amount of CaO can be 0.1%, 0.4%, 0.6%, 0.8%, 1.0%, and 1.2%. The amount of CaO can also be any amount between the exemplary amounts, for example, the amount of CaO can also be any amount between 0.4-0.8%.

[0064] MgO (magnesium oxide) belongs to the network exosome, which helps to improve the glass material, reduce the melting temperature, improve the chemical stability and optical properties of the glass, and can improve the elastic modulus in the base glass. However, too high a dosage of MgO will affect the precipitation of the target crystal. Therefore, when the dosage of MgO is 0-1.2%, it is beneficial to improve the comprehensive properties of the glass. Exemplarily, the dosage of MgO can be 0.1%, 0.4%, 0.6%, 0.8%, 1.0%, and 1.2%. The dosage of MgO can also be any dosage between the exemplary dosages, for example, the dosage of MgO can also be any dosage between 0.4-0.8%.

[0065] SrO (strontium oxide) can adjust the network structure of glass, improve the chemical stability and thermal stability of glass, help reduce the melting temperature of glass, and promote the melting and flow of glass. When the amount of SrO is 0-2.5%, it is beneficial to improve the comprehensive properties of glass. Exemplarily, the amount of SrO can be 0.1%, 0.6%, 1.2%, 1.6%, 2.0%, 2.5%. The amount of SrO can also be any amount between the exemplary amounts, for example, the amount of SrO can also be any amount between 1.2-2.0%.

[0066] BaO (barium oxide) can provide a stronger network destruction effect, which is helpful for the crystallization and ion exchange process of glass. When the amount of BaO is 0-2.3%, it is beneficial to improve the comprehensive properties of glass. Exemplarily, the amount of BaO can be 0.1%, 0.6%, 1.2%, 1.6%, 2.0%, 2.3%. The amount of BaO can also be any amount between the exemplary amounts, for example, the amount of BaO can also be any amount between 1.2-2.0%.

[0067] ZnO (zinc oxide) can improve the material and thermal properties of the parent glass, help refine the grains during the glass crystallization process, improve the optical properties of microcrystalline glass, reduce the high-temperature viscosity of the glass, and also help eliminate bubbles and improve the chemical resistance of the glass. However, ZnO exists in the form of zinc-oxygen tetrahedrons, and the network structure is loose. When its dosage is too high, the elastic modulus and hardness of the glass decrease. Therefore, when the dosage of ZnO is 0-2.4%, it is beneficial to improve the comprehensive properties of the glass. Exemplarily, the dosage of ZnO can be 0.1%, 0.4%, 0.8%, 1.5%, 2.0%, and 2.4%. The dosage of ZnO can also be any dosage between the exemplary dosages, for example, the dosage of ZnO can also be any dosage between 0.8-2.0%.

[0068] The dopant can change other properties of the glass, such as optical properties, thermal properties, etc. In this embodiment, the amount of the dopant can be 0.5%, 1.1%, 1.6%, 2.0%, 2.6%. The amount of the dopant can also be any amount between the exemplary amounts, and the amount of the dopant can also be any amount between 1.0-2.0%.

[0069] The clarifier can reduce the viscosity of the glass liquid, reduce or eliminate bubbles in the glass liquid, and improve the optical properties and mechanical strength of the glass during the glass melting process. The amount of the clarifier can be 0.2%, 0.6%, 0.8%, 1.0%, 1.3%. The amount of the clarifier can also be any amount between the exemplary amounts. For example, the amount of the clarifier can be any amount between 0.6-1.0%.

[0070] In an exemplary embodiment, the dopant includes one or more of La2O3, Y2O3, Ta2O5.

[0071] La2O3, Y2O3, and Ta2O5, as oxide dopants, can improve the process performance, optical properties, and mechanical properties of glass. Among them, La2O3 (lanthanum oxide) can increase the refractive index of glass and improve the thermal stability and mechanical properties of glass. Y2O3 (yttrium oxide) can reduce the melting temperature and viscosity of glass and improve the chemical stability and optical properties of glass. Ta2O5 (tantalum pentoxide) can increase the refractive index of glass, promote the crystallization process, and improve the thermal properties of glass. The dopant can be selected from La2O3, Y2O3, and Ta2O5, or several of them can be selected for compounding. For example, the dopant includes La2O3 and Y2O3 in a mass ratio of 1.1-2.0:1.

[0072] In an exemplary embodiment, the fining agent includes one or more of Sb2O3, SnO2, SnO, and CeO2.

[0073] When preparing glass, each component will release gas after melting. In this embodiment, the addition of a clarifier can promote the discharge of bubbles in the glass liquid to improve the transparency and uniformity of the glass. In this embodiment, the clarifier can be one of Sb2O3 (antimony oxide), SnO2 (tin dioxide), SnO (tin oxide), and CeO2 (cerium dioxide), or several of them can be selected for compounding. For example, the clarifier includes SnO2 and CeO2 in a mass ratio of 1.2-3.5:1.

[0074] An exemplary embodiment of the present disclosure provides a glass-ceramic, the glass-ceramic includes a first crystal phase and a second crystal phase, the first crystal phase includes lithium disilicate; the second crystal phase includes one or more of petalite, lithium metasilicate, zirconium oxide, and lithium phosphate. The glass-ceramic provided by the exemplary embodiment of the present disclosure is prepared by the composition for microcrystalline materials provided by the exemplary embodiment of the present disclosure.

[0075] Glass-ceramics is a composite material made by controlling the crystallization process of glass. In this embodiment, the glass-ceramics includes a first crystal phase and a second crystal phase, wherein the first crystal phase includes lithium disilicate (Li2Si2O5). As the main crystal phase of glass-ceramics, lithium disilicate can significantly improve the mechanical strength and hardness of glass-ceramics; and the rod-shaped crystals of lithium disilicate can also form an interlocking structure with the second crystal phase to improve the fracture toughness of glass-ceramics. The second crystal phase includes petalite (LiAlSiO4), lithium metasilicate (Li2SiO3), zirconium oxide (ZrO2), and lithium phosphate (Li3PO4), wherein petalite can improve the thermal and chemical stability of glass-ceramics; lithium metasilicate, as a metastable phase, can be transformed into a more stable lithium disilicate after heat treatment, which can affect the light transmittance of glass; zirconium oxide can improve the fracture toughness of glass-ceramics; lithium phosphate can be used as a nucleating agent to promote the nucleation and growth of other crystal phases.

[0076] The types and proportions of each crystalline phase in the microcrystalline glass are related to the components, proportions, and heat treatment process parameters of the composition for microcrystalline materials. Exemplarily, the microcrystalline glass includes a first crystalline phase and a second crystalline phase, the first crystalline phase includes lithium disilicate; the second crystalline phase includes petalite, lithium metasilicate, zirconium oxide, and lithium phosphate, wherein the mass of lithium disilicate accounts for 30-50% of the total mass of the microcrystalline glass, the mass of petalite accounts for 10-30% of the total mass of the microcrystalline glass, the mass of lithium metasilicate accounts for 5-15% of the total mass of the microcrystalline glass, the mass of zirconium oxide accounts for 5-20% of the total mass of the microcrystalline glass, and the mass of lithium phosphate accounts for 1-5% of the total mass of the microcrystalline glass.

[0077] In addition, by controlling the grain size of the crystalline phase, the optical properties, mechanical strength, thermal stability, etc. of the microcrystalline glass can also be improved. For example, in this embodiment, the grain size of the crystalline phase can be 10-50 nm.

[0078] In an exemplary embodiment, the glass-ceramic includes a strengthening layer located on at least one surface, and the depth of the strengthening layer is 100-150 μm.

[0079] In this embodiment, the strengthening layer on the surface of the microcrystalline glass can be formed by ion exchange technology. Ion exchange is a surface treatment technology for glass. During ion exchange, larger ions (such as K + ) replaces smaller ions (such as Na + or Li + ), resulting in compressive stress on the surface of the glass. This compressive stress can inhibit the further development of microcracks on the surface of the glass to improve the mechanical strength of the glass. After ion exchange, the ions on the surface of the glass will further diffuse into the interior of the glass under the action of mutual expansion, causing the alkali metal ions in the molten salt to migrate into the interior of the glass, and the alkali metal ions in the glass migrate to the surface of the glass to continue ion exchange with the alkali metal ions in the molten salt. The depth of the strengthening layer in this embodiment is the ion exchange depth (Depth of layer, Dol), and the depth of ion exchange can reach 100-150μm, indicating that the microcrystalline glass has a high compressive stress.

[0080] In addition to the ion exchange depth, the ion exchange capacity can also be reflected by the values ​​of the central tensile stress (CS) and the surface compressive stress (CT) of the microcrystalline glass. The surface compressive stress CS indicates the magnitude of the compressive stress on the surface of the glass. The greater the surface compressive stress, the better the impact resistance of the glass. In this embodiment, the surface compressive stress of the microcrystalline glass is 120-600MPa.

[0081] The central tensile stress CT indicates the tensile stress at the center of the glass. Appropriate central tensile stress can improve the strength, impact resistance and scratch resistance of the glass, but too high central tensile stress can also lead to a decrease in the mechanical properties of the glass. In this embodiment, the central tensile stress of the microcrystalline glass is 200-400 MPa.

[0082] like Figure 1 As shown, an exemplary embodiment of the present disclosure provides a method for preparing glass-ceramics, the preparation method comprising:

[0083] S110, melt-forming the microcrystalline material composition under first preset conditions to obtain a mother glass.

[0084] In step S110, the microcrystalline material composition is melted under a first preset condition to form a glass liquid; the glass liquid is then poured into a preheated mold for molding to obtain a matrix glass.

[0085] S120, heat-treating the mother glass under a second preset condition to obtain glass-ceramics.

[0086] The percentage of the mass of each component of the microcrystalline material composition to the total mass of the microcrystalline material composition is expressed as follows:

[0087] SiO2: 68.2-78.5%; Al2O3: 5.0-10.5%; alkali metal oxides: 10.3-18.7%; nucleating agent: 5.0-13.4%; alkali metal oxides include Li2O.

[0088] Before step S120, in order to facilitate subsequent processing, the mother glass can be cut into glass sheets of 0.3-1.0 mm, and then the glass sheets are processed by computer numerical control (CNC), edge sweeping, grinding, polishing, etc. to obtain a finely processed mother glass. Under the second preset condition, the finely processed mother glass is heat-treated to crystallize the mother glass to obtain a microcrystalline glass containing a crystalline phase.

[0089] In an exemplary embodiment, the first preset condition includes:

[0090] In the first stage, the temperature is kept at 1450-1550℃ for 4-6 hours;

[0091] In the second stage, annealing is performed at a temperature of 450-700°C.

[0092] In this embodiment, in the first stage, the components of the microcrystalline material composition can be melted to form glass liquid; because the glass will produce uneven cooling during the thermal processing, an annealing treatment is performed in the second stage to reduce the internal stress of the glass and reduce the risk of breakage during subsequent processing.

[0093] Exemplarily, in one embodiment, the first preset condition includes:

[0094] In the first stage, the temperature was kept at 1450°C for 6 hours;

[0095] In the second stage, annealing is performed at a temperature of 450°C.

[0096] In another embodiment, the first preset condition includes:

[0097] In the first stage, the temperature was kept at 1500°C for 5 hours;

[0098] In the second stage, annealing is performed at a temperature of 600°C.

[0099] In another embodiment, the first preset condition includes:

[0100] In the first stage, the temperature was kept at 1550°C for 4 hours;

[0101] In the second stage, annealing is performed at a temperature of 700°C.

[0102] In an exemplary embodiment, the second preset condition includes: keeping the temperature at 500-800° C. for 2-10 hours.

[0103] In this embodiment, the crystal phase in the microcrystalline glass can be adjusted by adjusting the temperature and time of the second preset condition.

[0104] The second precondition includes:

[0105] In the first stage, the temperature is kept at 550-600℃ for 4-6h;

[0106] In the second stage, the temperature is kept at 750-780℃ for 0.5-1h.

[0107] In this embodiment, the mother glass can form a crystal nucleus after the first stage of nucleation heat treatment, and then the crystal nucleus can grow to form microcrystals after the second stage of crystallization heat treatment. When the temperature is increased from the first stage to the second stage, the heating rate can be set to 10-20°C / h. Heating at a slower speed is conducive to improving the mechanical and optical properties of the microcrystalline glass.

[0108] Exemplarily, in one embodiment, the second preset condition includes:

[0109] In the first stage, the temperature was kept at 550°C for 6 h;

[0110] In the second stage, the temperature was kept at 750°C for 1h.

[0111] In another embodiment, the second preset condition includes:

[0112] In the first stage, the temperature was kept at 580°C for 5 h;

[0113] In the second stage, the temperature was kept at 760°C for 0.8h.

[0114] In another embodiment, the second preset condition includes:

[0115] In the first stage, the temperature was kept at 600°C for 4 h;

[0116] In the second stage, the temperature is kept at 750°C for 0.5h.

[0117] In an exemplary embodiment, the preparation method further comprises:

[0118] placing the glass-ceramics in a first molten salt and performing a first ion exchange treatment under a third preset condition to obtain a first-strengthened glass-ceramics;

[0119] The once strengthened glass-ceramics is placed in a second molten salt, and a second ion exchange treatment is performed under a fourth preset condition to obtain a second strengthened glass-ceramics.

[0120] In this embodiment, the microcrystalline glass is strengthened twice, which can significantly improve the mechanical properties and durability of the glass.

[0121] In an exemplary embodiment, the percentage of the mass of each component of the first molten salt to the total mass of the first molten salt is expressed as follows:

[0122] Potassium salt 59.9-79.9%;

[0123] Sodium salt 19.8-39.9%;

[0124] Lithium nitrate 0.1-0.2%.

[0125] In this embodiment, potassium salt is mainly used for surface exchange, and sodium salt is mainly used for deep exchange. Therefore, in the first molten salt, the content of sodium salt is higher, which is conducive to deep exchange during the first strengthening. The potassium salt can be potassium nitrate, for example, and the sodium salt can be sodium nitrate, for example.

[0126] Exemplarily, in one embodiment, the percentage of the mass of each component of the first molten salt to the total mass of the first molten salt is expressed as follows:

[0127] Potassium salt 59.9%;

[0128] Sodium salt 39.9%;

[0129] Lithium nitrate 0.2%.

[0130] In another embodiment, the percentage of the mass of each component of the first molten salt to the total mass of the first molten salt is expressed as follows:

[0131] Potassium salt 72.6%;

[0132] Sodium salt 27.25%;

[0133] Lithium nitrate 0.15%.

[0134] In another embodiment, the percentage of the mass of each component of the first molten salt to the total mass of the first molten salt is expressed as follows:

[0135] Potassium salt 79.9%;

[0136] Sodium salt 20.0%;

[0137] Lithium nitrate 0.2%.

[0138] In an exemplary embodiment, the percentage of the mass of each component of the second molten salt to the total mass of the first molten salt is as follows:

[0139] Potassium salt 80.0-100.0%;

[0140] Sodium salt 0-20.0%.

[0141] In this embodiment, the second molten salt has a higher content of potassium salt, which is beneficial for surface exchange during the second strengthening. The potassium salt may be, for example, potassium nitrate, and the sodium salt may be, for example, sodium nitrate.

[0142] Exemplarily, in one embodiment, the percentage of the mass of each component of the second molten salt to the total mass of the first molten salt is shown as follows:

[0143] Potassium salt 80.0%;

[0144] Sodium salt 20.0%.

[0145] In another embodiment, the percentage of the mass of each component of the second molten salt to the total mass of the first molten salt is shown as follows:

[0146] Potassium salt 89.3%;

[0147] Sodium salt 10.7%.

[0148] In another embodiment, the percentage of the mass of each component of the second molten salt to the total mass of the first molten salt is shown as follows:

[0149] Potassium salt 100.0%.

[0150] In an exemplary embodiment, the third preset condition includes: keeping warm at a temperature of 450-550° C. for 4-8 hours.

[0151] In this embodiment, by controlling the third preset condition, the ion migration speed during the primary strengthening can be controlled to control the depth of ion exchange.

[0152] Exemplarily, in one embodiment, the third preset condition includes: keeping warm at a temperature of 450° C. for 8 hours.

[0153] In another embodiment, the third preset condition includes: keeping the temperature at 500° C. for 6 hours.

[0154] In another embodiment, the third preset condition includes: keeping warm at a temperature of 550° C. for 4 hours.

[0155] In an exemplary embodiment, the fourth preset condition includes: maintaining the temperature at 450-500° C. for 0.5-2 h.

[0156] In this embodiment, by controlling the fourth preset condition, the ion migration speed during the secondary strengthening can be controlled to control the depth of ion exchange.

[0157] Exemplarily, in one embodiment, the fourth preset condition includes: keeping warm at a temperature of 450° C. for 2 hours.

[0158] In another embodiment, the fourth preset condition includes: keeping warm at a temperature of 480° C. for 1.0 h.

[0159] In another embodiment, the fourth preset condition includes: keeping the temperature at 500° C. for 0.5 h.

[0160] An exemplary embodiment of the present disclosure provides an electronic device, the electronic device includes a cover plate and a housing, the material of the cover plate and / or the housing is a microcrystalline glass prepared from the above microcrystalline material composition or the above microcrystalline glass or the above microcrystalline glass prepared by the above microcrystalline glass preparation method. The electronic device is, for example, a mobile phone, a laptop computer, a tablet computer, and a wearable device.

[0161] In order to more clearly explain the technical solution of the present disclosure, the present disclosure lists specific embodiments of microcrystalline glass, and the beneficial effects of selecting the above-mentioned ranges of each parameter are explained by giving specific experimental data through specific embodiments.

[0162] Example

[0163] It should be noted that, unless otherwise specified, the raw materials in the following examples can be obtained from commercial sources.

[0164] Embodiment: A method for preparing glass-ceramics, comprising:

[0165] (1) 73.90% of SiO2, 7.40% of Al2O3, 11.90% of Li2O, 0.02% of K2O, 0.10% of CaO, 0.10% of Y2O3, 2.00% of P2O5, 4.30% of ZrO2, 0.03% of Sb2O3, and 0.05% of SnO2 are mixed to obtain a composition for a microcrystalline material.

[0166] (2) The microcrystalline material composition is kept at a temperature of 1500° C. for 5 hours to form a molten glass liquid; the molten glass liquid is then poured into a preheated mold for molding, and the molded glass is annealed at a temperature of 600° C. to obtain a matrix glass.

[0167] (3) The mother glass is cut into glass sheets with a thickness of 0.6 mm, and the glass sheets are subjected to CNC, edge sweeping, grinding, and polishing processes to obtain a finely processed mother glass.

[0168] (4) The processed mother glass is kept at 580°C for 4 hours and then kept at 760°C for 1 hour for crystallization to obtain microcrystalline glass.

[0169] (5) Placing the glass-ceramics in a first molten salt and keeping it at 480°C for 8 hours to perform a first ion exchange treatment to obtain a once-strengthened glass-ceramics; placing the once-strengthened glass-ceramics in a second molten salt and keeping it at 470°C for 1 hour to perform a second ion exchange treatment to obtain a twice-strengthened glass-ceramics.

[0170] The first molten salt is prepared by the following method: 59.9% KNO3, 39.9% NaNO3 and 0.2% LiNO3 are mixed and placed in a furnace to prepare the first molten salt.

[0171] The second molten salt is prepared by the following method: 80% KNO3 and 20% NaNO3 are mixed and placed in a furnace to prepare the second molten salt.

[0172] In order to more clearly explain the technical solution of the present disclosure, the present disclosure also lists Examples 2-12 of microcrystalline glass, wherein the setting parameters of Examples 2-12 are shown in Table 1.

[0173] Table 1 shows a specific embodiment of the glass-ceramics in the present disclosure. It should be noted that, except for the parameters listed in Table 1, other parameters of Examples 2-12 are substantially the same as those of Example 1.

[0174] Table 1 Formulation and process parameters of glass-ceramics of Examples 1-12

[0175]

[0176] Table 1 (Continued) Formulation and process parameters of glass-ceramics of Examples 1-12

[0177]

[0178] Performance Testing

[0179] The glass-ceramics prepared in Examples 1-12 were used as test samples, and performance tests were performed on them according to the following method. The test results are recorded in Table 2.

[0180] 1. Crystal phase type: The corresponding crystal phase in the microcrystalline glass is obtained by comparing the standard PDF card analysis using an X-ray diffractometer; Figure 2 The XRD test diagram of the glass-ceramics of Example 1 is shown. Figure 2 It can be seen that the crystalline phase of the glass-ceramics of Example 1 includes lithium disilicate (Li2Si2O5) and petalite (LiAlSiO4).

[0181] 2. Surface compressive stress (CS), central tensile stress (CT) and ion exchange depth (Dol): The CS value, CT value and Dol value of the microcrystalline glass are measured using a scattered light photoelastic stress meter; the stress test graph can be obtained by fitting the ion exchange depth-stress value; among them, Figure 3 3 shows a stress test graph of the microcrystalline glass of Example 2, where the horizontal axis represents the ion exchange depth (μm) and the vertical axis represents the stress value (MPa).

[0182] 3. Ball drop height: After polishing both surfaces of a 165×70mm long and wide microcrystalline glass plate, place it on a rubber frame and fix it. Drop a 32g steel ball from a height of 40cm to determine the impact the glass plate can withstand without breaking. If it does not break, increase the height by 5cm and continue testing until it breaks.

[0183] 4. Drop with 180-grit sandpaper: After polishing the two surfaces of a 165×70mm long and wide microcrystalline glass plate, use double-sided tape to stick it to a 200g iron sheet of the same size as the test glass, and use a drop machine to perform a drop test, dropping it onto 180-grit sandpaper fixed on the ground. The drop test starts from 50cm, and after checking that there is no damage after the drop, increase the drop test by 5cm until it breaks.

[0184] Table 2 Performance test table of glass-ceramics of Examples 1-12

[0185]

[0186] Table 2 (Continued) Performance test table of glass-ceramics of Examples 1-12

[0187]

[0188] Combining the data in Table 1 and Table 2, it can be seen that the microcrystalline glass prepared by the method of the present disclosure has an ion exchange depth of ≥100-150μm, a surface compressive stress of ≥120MPa, a central tensile stress of ≥200MPa, a 130g central ball drop height of ≥130cm, and a 180-mesh sandpaper drop height of ≥1.65m, indicating that the microcrystalline glass of the present disclosure has excellent anti-drop performance. In addition, the fracture toughness of the microcrystalline glass in each embodiment of the present disclosure can reach 1.0MPa·m 1 / 2 The above indicates that it has good impact resistance; the average spectral transmittance of the microcrystalline glass in each embodiment in the visible light band is ≥90%, indicating that it has good optical properties.

[0189] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the invention disclosed herein. The present disclosure is intended to cover any variations, uses or adaptations of the present disclosure that follow the general principles of the present disclosure and include common knowledge or customary techniques in the art that are not disclosed in the present disclosure. The description and examples are to be considered exemplary only, and the true scope and spirit of the present disclosure are indicated by the claims.

[0190] It should be understood that the present disclosure is not limited to the exact structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims

1. A composition for microcrystalline material, characterized in that: The percentage of the mass of each component of the composition to the total mass of the composition is expressed as follows: SiO2: 68.2-78.5%; Al2O3: 5.0-10.5%; Alkali metal oxide: 10.3-18.7%; Nucleating agent: 5.0-13.4%; The alkali metal oxide includes Li2O.

2. The composition for microcrystalline materials according to claim 1, wherein the alkali metal oxide further comprises other alkali metal oxides, and the mass of the Li2O accounts for 73.3-99.6% of the total mass of the alkali metal oxides.

3. The composition for microcrystalline material according to claim 2, characterized in that: The other alkali metal oxides include one or both of Na2O and K2O.

4. The composition for microcrystalline material according to claim 1, characterized in that: The nucleating agent includes ZrO2 and P2O5, the mass of ZrO2 accounts for 4.0-8.7% of the total mass of the raw materials of the microcrystalline glass, and the mass of P2O5 accounts for 1.0-4.7% of the total mass of the raw materials of the microcrystalline glass.

5. The composition for microcrystalline material according to claim 4, characterized in that: The mass ratio of the ZrO2 to the P2O5 is 2.1-2.5:

1.

6. The composition for microcrystalline material according to claim 1, characterized in that: The composition further comprises at least one of the following components: CaO: 0-1.2%; MgO: 0-1.2%; SrO: 0-2.5%; BaO: 0-2.3%; ZnO: 0-2.4%; Dopant: 0-2.6%; Clarifying agent: 0-1.3%.

7. The composition for microcrystalline material according to claim 6, characterized in that: The dopant includes one or more of La2O3, Y2O3, and Ta2O5.

8. The composition for microcrystalline material according to claim 6, characterized in that: The clarifier includes one or more of Sb2O3, SnO2, SnO, and CeO2.

9. A glass-ceramic, characterized in that: The microcrystalline glass is prepared from the composition for microcrystalline materials described in any one of claims 1 to 8, and the microcrystalline glass includes a first crystal phase and a second crystal phase, the first crystal phase includes lithium disilicate; the second crystal phase includes one or more of petalite, lithium metasilicate, zirconium oxide, and lithium phosphate. 10 . The microcrystalline glass according to claim 9 , comprising a strengthening layer located on at least one surface, and a depth of the strengthening layer is 100-150 μm.

11. A method for preparing glass-ceramics, characterized in that: The preparation method comprises: Melting and molding the microcrystalline material composition under a first preset condition to obtain a matrix glass; heat-treating the mother glass under a second preset condition to obtain the glass-ceramics; The percentage of the mass of each component of the microcrystalline material composition to the total mass of the microcrystalline material composition is expressed as follows: SiO2: 68.2-78.5%; Al2O3: 5.0-10.5%; Alkali metal oxide: 10.3-18.7%; Nucleating agent: 5.0-13.4%; The alkali metal oxide includes Li2O.

12. An electronic device, characterized in that: The electronic device includes a cover plate and a shell, and the material of the cover plate and / or the shell is microcrystalline glass prepared by the composition for microcrystalline materials as described in any one of claims 1 to 8, or the microcrystalline glass as described in any one of claims 9 to 10, or the microcrystalline glass prepared by the method for preparing microcrystalline glass as described in claim 11.

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