Pressure-resistant strengthened glass ceramic, cover plate glass, electronic equipment and glass device

Abstract

The present application belongs to the technical field of glass ceramics, and provides pressure-resistant strengthened glass ceramic, cover plate glass, electronic equipment and a glass device. In the present application, a zinc aluminate spinel–magnesium aluminate spinel solid solution is used as a main crystalline phase of the glass ceramic, making the glass ceramic obtain high intrinsic strength; and by chemically strengthening the glass ceramic that has a thickness of more than 0.7 mm and contains specific contents of Li ions and Na ions, and by making the surface composition of the prepared strengthened glass ceramic meet specific requirements, the pressure resistance of the strengthened glass ceramic is significantly improved, and the strengthened glass ceramic thus obtains good compression resistance. When the strengthened glass ceramic is used in electronic equipment, the electronic equipment can be used in application environments having relatively high requirements for pressure resistance, for example, the electronic equipment can better meet the application requirements of a water environment (such as a deep-sea environment), and can be used in a deep-water environment, etc.

Description

Pressure-resistant strengthened glass ceramic, cover glass, electronic device, and glass article

[0001] Cross Reference to Related Applications

[0002] This application claims priority to the Chinese patent application with the title of "Pressure-resistant strengthened glass ceramic, cover glass, electronic device, and glass article", the application number of 202410740146.3, which was filed on June 7, 2024, with the State Intellectual Property Office of China, the content of which is incorporated herein by reference in its entirety. TECHNICAL FIELD

[0003] The present application relates to the technical field of glass-ceramics, in particular, to a pressure-resistant strengthened glass ceramic, cover glass, electronic device, and glass article. BACKGROUND

[0004] With the popularity of smart electronic devices, people's requirements for the performance of electronic devices are also getting higher and higher. For example, more and more smart wearable devices require to be used in water environment, such as in swimming, diving, and other environments. When used in water environment, it needs to meet certain pressure resistance requirements. Because when used in water environment, in addition to having to cope with the possibility of destructive impact, smart wearable devices also have to withstand the pressure from water. Only with sufficient pressure resistance, can it be ensured that the structure of the smart wearable device will not be damaged by excessive water pressure in deep water.

[0005] As we all know, the deeper the depth, the greater the water pressure. In the underwater environment, the water depth increases by 1 atmosphere for every 10 meters. Therefore, the diving environment, especially the deep diving environment, will exert a great pressure on the smart wearable device. Similarly, some devices for manned exploration of deep sea require high pressure resistance of the transparent glass window. At present, although the performance of the glass ceramic on the market is generally better than that of ordinary glass, its pressure resistance still needs to be further improved.

[0006] It should be noted that this part of the application only provides background technology related to the application, and does not necessarily constitute prior art or known technology. SUMMARY

[0007] Spinel crystals have excellent properties such as high hardness and high modulus. The use of glass ceramics with spinel crystal phase as the main crystal phase for chemical strengthening to prepare strengthened glass ceramics is more conducive to obtaining strengthened glass ceramic materials with excellent extrusion resistance than the use of ordinary glass.

[0008] The purpose of the present application is to provide a strengthened glass ceramic with spinel crystal phase as the main crystal phase and excellent extrusion resistance. In order to achieve the above purpose, the present application provides the following technical solutions:

[0009] In a first aspect, there is provided a strengthened glass-ceramic, which is plate-shaped, the strengthened glass-ceramic having a thickness t greater than 0.7 mm, preferably, the thickness t is not less than 0.8 mm, more preferably, the thickness t is not less than 0.9 mm;

[0010] The strengthened glass-ceramic comprises a main crystal phase of a zinc aluminate-magnesium aluminate spinel solid solution and a secondary crystal phase of zirconia; the strengthened glass-ceramic has a compressive stress layer on the surface and a tensile stress in the interior;

[0011] The strengthened glass-ceramic comprises Li2O and Na2O at the center or in the composition of the tensile stress layer, and the mass percentage of Li2O is greater than 1.00%, preferably, the mass percentage of Li2O is greater than 1.30%, more preferably, the mass percentage of Li2O is greater than or equal to 1.50%, the mass percentage of Na2O is greater than 1.00%, preferably, the mass percentage of Na2O is greater than 2.00%, more preferably, the mass percentage of Na2O is greater than 2.70% in terms of mass percentage of oxides;

[0012] The strengthened glass-ceramic has a surface K2O mass percentage of 2.00% to 7.50%, preferably, the strengthened glass-ceramic has a surface K2O mass percentage of 2.50% to 6.50%, more preferably, the strengthened glass-ceramic has a surface K2O mass percentage of 3.00% to 6.00% in terms of mass percentage of oxides;

[0013] The strengthened glass-ceramic has a surface Na2O mass percentage of less than or equal to 0.010%, preferably, the strengthened glass-ceramic has a surface Na2O mass percentage of less than or equal to 0.005%, more preferably, the strengthened glass-ceramic has a surface Na2O mass percentage of less than or equal to 0.002% in terms of mass percentage of oxides;

[0014] The strengthened glass-ceramic satisfies 5.00 μm≤DOL_K≤20.00 μm, preferably, 5.50 μm≤DOL_K≤18.00 μm, more preferably, 6.00 μm≤DOL_K≤16.00 μm, wherein DOL_K is the K + diffusion depth from the main surface of the strengthened glass-ceramic.

[0015] It should be understood that the strengthened glass-ceramic of the present application is made from a glass-ceramic by chemical strengthening treatment, and the composition at the center or the tensile stress layer of the strengthened glass-ceramic is the same as or substantially the same as that of the glass-ceramic. That is, in the present application, the glass-ceramic used to prepare the strengthened glass-ceramic also contains a certain amount of Li2O and Na2O.

[0016] In the present application, by containing a certain amount of Li2O and Na2O in the glass ceramic, not only the fracture toughness of the glass ceramic can be increased, so that it is not easy to break when subjected to extrusion or impact, but also the chemical strengthening effect of the glass ceramic can be improved.

[0017] In the present application, by taking the zinc-aluminum spinel-magnesium-aluminum spinel solid solution as the main crystal phase of the glass ceramic, the glass ceramic obtains high intrinsic strength. By chemically strengthening the glass ceramic with a thickness greater than 0.7 mm and containing specific contents of Li ions and Na ions, and by making the surface composition of the prepared strengthened glass ceramic meet specific requirements, the compressive capacity of the strengthened glass ceramic is significantly improved, and the strengthened glass ceramic obtains excellent extrusion resistance. In the present application, (Zn, Mg)Al2O4 represents the zinc-aluminum spinel-magnesium-aluminum spinel solid solution (or also referred to as zinc-magnesium spinel solid solution, zinc spinel-magnesium spinel solid solution, zinc-magnesium-aluminum spinel solid solution).

[0018] As an optional embodiment, the surface K2O mass percentage of the strengthened glass ceramic is 3.91%, 4.16%, 3.96%, 4.12%, 4.53%, 3.24%, 4.55%, 4.51%, 4.68%, 5.75%, 3.85%, 4.48%, 5.69%, 5.45%, 5.57%, or 5.54%; and / or,

[0019] The DOL_K of the strengthened glass ceramic is 7.70 μm, 9.60 μm, 10.30 μm, 8.40 μm, 10.40 μm, 8.60 μm, 14.10 μm, 12.50 μm, 6.20 μm, 9.80 μm, 12.80 μm, 9.10 μm, 8.30 μm, 8.80 μm, 11.40 μm, 10.60 μm, 11.80 μm, or 11.70 μm.

[0020] As an optional embodiment, the strengthened glass ceramic satisfies: along the thickness direction of the strengthened glass ceramic, the concentration of K element presents a nonlinear decreasing trend from the main surface of the strengthened glass ceramic to the center of the strengthened glass ceramic.

[0021] As an optional embodiment, the composition at the center of the strengthened glass ceramic or the composition of the compressive stress layer contains Al2O3 with a mass percentage greater than or equal to 30.00% in terms of mass percentage of oxides.

[0022] In the present application, by controlling the mass percentage of Al2O3 in the glass-ceramic to be greater than or equal to 30%, on the one hand, the desired content of main crystal phase can be precipitated, so that the glass-ceramic obtains high intrinsic strength (or also known as inherent strength), on the other hand, a certain amount of alumina also exists in the glass phase, and the alumina existing in the glass phase can enter the glass network structure in the form of [AlO4] tetrahedron to form a unified grid with [SiO4], so that the connection degree of the network is enhanced, the strength and stability of the glass network structure are improved, and thus the intrinsic strength of the glass-ceramic is further improved. At the same time, the [AlO4] tetrahedron in the glass phase can appropriately expand the ion exchange channel, improve the chemical strengthening effect of the glass-ceramic, and be more conducive to obtaining a strengthened glass-ceramic with excellent mechanical strength performance.

[0023] As an optional embodiment, the composition at the center of the strengthened glass-ceramic or the composition of the tensile stress layer comprises ZrO2 with a mass percentage greater than or equal to 3.00% in terms of mass percentage of oxides.

[0024] In the present application, by controlling the mass percentage of zirconia in the glass-ceramic to be greater than or equal to 3.00%, the intrinsic strength of the glass-ceramic is improved, and the surface stress level of the strengthened glass-ceramic obtained thereby is improved. On the one hand, as a nucleating agent, zirconia will disperse in the glass phase in the form of nanoscale grains after heat treatment, which can increase the hardness of the glass-ceramic, thereby effectively improving the shatter resistance of the glass-ceramic. On the other hand, zirconia exists in the glass phase in the form of [ZrO8] cube, which can enhance the interionic force and make the glass structure more compact, thereby being conducive to improving the mechanical strength of the glass phase. At the same time, zirconia can significantly improve the surface compressive stress formed by ion exchange, thereby improving the surface stress level of the strengthened glass-ceramic obtained thereby.

[0025] As an optional embodiment, the thickness t of the strengthened glass-ceramic is 0.85 mm to 2.00 mm, preferably, the thickness t is 0.90 mm to 1.50 mm; and / or, the strengthened glass-ceramic is 2D, 2.5D, 3D or special-shaped; and / or, the strengthened glass-ceramic is equal-thickness or unequal-thickness. In the present application, when the thickness of the strengthened glass-ceramic is small, the compression resistance will be significantly reduced, and when the thickness is too large, on the one hand, it will lead to an increase in weight, which is not conducive to the light and thin electronic devices, and on the other hand, too large thickness will lead to a decrease in transmittance of the glass-ceramic, so that the transmittance performance of the glass-ceramic is poor. "Unequal thickness" means that the strengthened glass-ceramic comprises at least two parts with different thicknesses.

[0026] As an optional embodiment, the composition at the center of the strengthened glass-ceramic or the composition of the tensile stress layer comprises:

[0027] Si02: 25.00% to 55.00%, Al203: 30.00% to 55.00%, Zr02: 3.00% to 8.00%, MgO: 2.00% to 5.00%, ZnO: 5.00% to 15.00%, Na20: 1.00% to 10.00%, K20: 0% to 5.00%, Li20: 1.00% to 6.00%, CaO: 0% to 6.00%, B203: 0% to 10.00%, BaO: 0% to 10.00%, Y203: 0% to 6.00%, La203: 0% to 12.00%.

[0028] By adjusting and controlling the content range of each oxide component, it is beneficial to ensure that the strengthened glass-ceramic satisfying the desired crystal phase structure is obtained, while it is also beneficial to ensure that the strengthened glass-ceramic obtains excellent optical performance and high intrinsic strength.

[0029] As an optional embodiment, the composition at the center of the strengthened glass-ceramic or the compressive stress layer comprises, in mass percent of oxides:

[0030] SiO2in a mass percent of 30.00% to 42.00%, preferably, SiO2in a mass percent of 35.00% to 40.00%; and / or, Al2O3in a mass percent of 32.00% to 42.00%, preferably, Al2O3in a mass percent of 34.00% to 42.00%; and / or, ZrO2in a mass percent of 4.00% to 7.00%, preferably, ZrO2in a mass percent of 5.00% to 6.00%; and / or, MgO in a mass percent of 2.50% to 4.00%, preferably, MgO in a mass percent of 2.50% to 3.50%; and / or, ZnO in a mass percent of 9.00% to 13.00%, preferably, ZnO in a mass percent of 9.00% to 11.00%; and / or, Na2O in a mass percent of 1.00% to 8.00%, preferably, Na2O in a mass percent of 2.00% to 6.00%; and / or, K2O in a mass percent of 0% to 3.00%, preferably, K2O in a mass percent of 0% to 1.00%; and / or, Li2O in a mass percent of 1.00% to 4.00%, preferably, Li2O in a mass percent of 2.00% to 3.00%; and / or, CaO in a mass percent of 0% to 3.00%, preferably, CaO in a mass percent of 0% to 1.50%; and / or, B2O3in a mass percent of 0% to 8.00%, preferably, B2O3in a mass percent of 0% to 4.00%; and / or, BaO in a mass percent of 0% to 7.00%, preferably, BaO in a mass percent of 0% to 4.00%; and / or, Y2O3in a mass percent of 0% to 4.00%, preferably, Y2O3in a mass percent of 0% to 2.00%; and / or, La2O3in a mass percent of 0% to 5.00%, preferably, La2O3in a mass percent of 0% to 3.00%.

[0031] As an optional embodiment, the composition at the center of the strengthened glass ceramic or the composition of the compressive stress layer comprises, in mass percent of oxides:

[0032] SiO2in a mass percent of 37.08%, 36.87%, 33.23%, 37.43%, 37.40%, 38.33%, 36.05%, 35.67%, 32.39%, 37.50%, 35.64%, 37.32%, or 36.31%; and / or,

[0033] Al2O3in a mass percent of 35.83%, 36.98%, 36.27%, 37.52%, 36.60%, 37.07%, 34.84%, 34.55%, 35.88%, 38.63%, 36.23%, or 35.10%; and / or,

[0034] Zr02in a mass percent of 5.69%, 5.65%, 5.61%, 5.74%, 5.81%, 5.89%, 5.54%, 5.48%, 5.76%, 5.72%, 5.99%, or 5.58%; and / or,

[0035] MgO in a mass percent of 3.00%, 2.98%, 3.04%, 3.03%, 3.06%, 3.10%, 2.92%, 2.89%, 3.01%, 3.27%, or 2.94%; and / or,

[0036] ZnO in a mass percent of 10.77%, 10.71%, 10.55%, 10.87%, 11.01%, 11.15%, 10.46%, 10.37%, 12.50%, 10.82%, 11.33%, or 10.54%; and / or,

[0037] Na20 in a mass percent of 2.86%, 2.85%, 2.89%, 3.00%, 1.69%, 2.79%, 2.76%, 3.31%, 4.61%, 3.01%, or 8.00%; and / or,

[0038] preferably free of K20; and / or,

[0039] Li20 in a mass percent of 2.35%, 1.55%, 1.50%, 1.77%, 1.60%, 1.62%, 2.28%, 2.27%, 2.24%, 1.60%, 1.57%, 2.85%, or 1.53%; and / or,

[0040] CaO in a mass percent of 0%, 0.75%, 1.15%, or 0.92%; and / or,

[0041] B203in a mass percent of 0% or 7.07%; and / or,

[0042] BaO in a mass percent of 2.42%, 2.41%, 6.94%, 0%, 2.35%, or 2.32%; and / or,

[0043] Y203in a mass percent of 0%, 1.52%, or 0.60%; and / or,

[0044] La203in a mass percent of 0%, 2.17%, or 3.69%.

[0045] As an optional embodiment, in the composition at the center of the strengthened glass ceramic or the tensile stress layer, the mass percentage of Na2O [Na2O] and the mass percentage of Li2O [Li2O] satisfy the following relationship: [Na2O] / [Li2O]=0.60-6.00, preferably 0.90-5.00, more preferably 1.00-3.00; and / or

[0046] In the composition at the center of the strengthened glass ceramic or the tensile stress layer, the mass percentage of Li2O [Li2O] and the mass percentage of SiO2 [SiO2] satisfy the following relationship: [Li2O] / [SiO2]=0.03-0.20, preferably 0.04-0.15, more preferably 0.04-0.10.

[0047] On the basis of adjusting and controlling the content range of each oxide component, by adjusting and controlling the matching relationship between each oxide component, especially the mass percentage relationship between Na2O and Li2O and between Li2O and SiO2, the intrinsic strength and chemical strengthening effect of the glass ceramic are improved, and then the strengthened glass ceramic with excellent mechanical strength performance is obtained.

[0048] As an optional embodiment, in the strengthened glass ceramic, the average crystal size is not more than 20.0 nm, preferably 1.0 nm-10.0 nm, more preferably 4.0 nm-9.0 nm, more preferably 4.0 nm-8.0 nm; and / or

[0049] In the strengthened glass ceramic, the total content of crystal phase is 25%-60%, preferably 30%-55%, more preferably 40%-50% by mass percentage.

[0050] By making the glass ceramic satisfy the desired total content of crystal phase / crystallinity and appropriate average crystal size, the glass ceramic can maintain excellent optical performance while satisfying excellent mechanical strength performance and high intrinsic strength.

[0051] As an optional embodiment, in the strengthened glass ceramic, the average crystal size is 5.0 nm, 6.8 nm, 6.4 nm, 6.5 nm, 8.1 nm, 7.0 nm, 6.1 nm, 5.1 nm or 6.2 nm; and / or

[0052] In the strengthened glass ceramic, the total content of crystal phase is 48.69%, 45.11%, 49.52%, 47.85%, 54.07%, 51.56%, 45.49%, 44.77%, 52.28%, 35.52%, 48.75% or 44.33% by mass percentage.

[0053] As an optional embodiment, the strengthened glass ceramic is transparent in the visible light wavelength range, preferably, the transmittance of the strengthened glass ceramic at a wavelength of 550 nm is ≥ 85.00% at a thickness of 0.90 mm, preferably the transmittance is ≥ 87.00%.

[0054] The strengthened glass ceramic satisfying the transmittance can ensure good light transmittance, good transparent effect, and is suitable for use in electronic device display screens which have requirements for display effect.

[0055] As an optional embodiment, the Vickers hardness of the strengthened glass ceramic is greater than or equal to 750 kgf / mm 2 , preferably the Vickers hardness of the strengthened glass ceramic is greater than or equal to 790 kgf / mm 2 ; and / or,

[0056] The fracture toughness value of the strengthened glass ceramic is greater than or equal to 1.00 MPa·m 0.5 , preferably the fracture toughness value of the strengthened glass ceramic is greater than or equal to 1.20 MPa·m 0.5 , more preferably the fracture toughness value of the strengthened glass ceramic is greater than or equal to 1.50 MPa·m 0.5 ; and / or,

[0057] The strengthened glass ceramic has a |CT_AV| of not more than 60.00 MPa, preferably has a |CT_AV| of 4.00 MPa to 55.00 MPa, preferably has a |CT_AV| of 4.00 MPa to 20.00 MPa, |CT_AV| being the absolute value of the average tensile stress; and / or,

[0058] The strengthened glass ceramic has a |CT_CV| of not more than 75.00 MPa, preferably has a |CT_CV| of 5.00 MPa to 70.00 MPa, preferably has a |CT_CV| of 6.00 MPa to 25.00 MPa, |CT_CV| being the absolute value of the maximum tensile stress.

[0059] By making the strengthened glass ceramic have high Vickers hardness and fracture toughness, the strengthened glass ceramic is not easy to break when subjected to extrusion or impact, which is beneficial to improve the compression resistance of the strengthened glass ceramic. And by making the strengthened glass ceramic satisfy the suitable stress structure, it is beneficial to play the improvement effect of the stress structure on the mechanical strength performance, especially the excellent compression resistance improvement effect to be achieved in the present application.

[0060] As an optional embodiment, the Vickers hardness of the strengthened glass ceramic is 840 kgf / mm 2 , 848 kgf / mm 2 , 855 kgf / mm2 , 879 kgf / mm 2 , 889 kgf / mm 2 , 836 kgf / mm 2 , 911 kgf / mm 2 , 897 kgf / mm 2 , 807 kgf / mm 2 , 894 kgf / mm 2 , 883 kgf / mm 2 , 873 kgf / mm 2 , 795 kgf / mm 2 , 863 kgf / mm 2 , 850 kgf / mm 2 , 856 kgf / mm 2 , or 860 kgf / mm 2 ; and / or,

[0061] the strengthened glass-ceramic has a fracture toughness value of 1.64 MPa-m 0.5 , 1.65 MPa-m 0.5 , 1.66 MPa-m 0.5 , 1.70 MPa-m 0.5 , 1.71 MPa-m 0.5 , 1.63 MPa-m 0.5 , 1.74 MPa-m 0.5 , 1.72 MPa-m 0.5 , 1.59 MPa-m 0.5 , 1.69 MPa-m 0.5 , 1.57 MPa-m 0.5 , or 1.67 MPa-m 0.5 ; and / or,

[0062] the strengthened glass-ceramic has a |CT AV| of 6.68 MPa, 5.85 MPa, 12.45 MPa, 5.45 MPa, 7.33 MPa, 7.79 MPa, 10.91 MPa, 14.64 MPa, 9.98 MPa, 6.25 MPa, 13.15 MPa, 8.58 MPa, 6.33 MPa, 7.91 MPa, 10.75 MPa, 12.77 MPa, 13.58 MPa, 9.47 MPa, or 7.98 MPa; and / or,

[0063] The |CT_CV| of the strengthened glass ceramic is 7.87 MPa, 6.96 MPa, 15.32 MPa, 6.84 MPa, 8.12 MPa, 9.01 MPa, 11.79 MPa, 17.92 MPa, 11.70 MPa, 7.76 MPa, 15.90 MPa, 9.45 MPa, 8.68 MPa, 9.13 MPa, 12.07 MPa, 14.12 MPa, 15.74 MPa, 10.75 MPa, or 9.02 MPa.

[0064] As an optional embodiment, a 10 mm diameter round head metal press rod is used to stepwise apply a load vertically downward at a rate of 10 mm / min to press the center of the main surface of the strengthened glass ceramic, and the single-rod static pressure strength of the strengthened glass ceramic is greater than 800 N.

[0065] As an optional embodiment, the strengthened glass ceramic is prepared by chemical strengthening treatment of a glass ceramic having a fracture toughness of not less than 1.40 MPa·m 0.5 As an optional embodiment, the strengthened glass ceramic is prepared by single-step chemical strengthening treatment of a glass ceramic having a fracture toughness of not less than 1.40 MPa·m 0.5 As an optional embodiment, the strengthened glass ceramic is prepared by single-step chemical strengthening treatment of a glass ceramic having a fracture toughness of not less than 1.40 MPa·m 0.5 As an optional embodiment, the strengthened glass ceramic is prepared by single-step chemical strengthening treatment of a glass ceramic having a fracture toughness of not less than 1.40 MPa·m

[0066] In a second aspect, a cover glass is provided, which is made of or comprises the strengthened glass ceramic according to any of the embodiments of the first aspect.

[0067] In a third aspect, an electronic device is provided, which comprises the strengthened glass ceramic according to any of the embodiments of the first aspect.

[0068] As an optional embodiment, the electronic device comprises a housing assembled on the outside of the electronic device, and the housing comprises the strengthened glass ceramic according to any of the embodiments of the first aspect.

[0069] As an optional embodiment, the housing comprises a display screen cover plate assembled on the front side of the electronic device, and the display screen cover plate comprises the strengthened glass ceramic according to any of the embodiments of the first aspect.

[0070] As an optional embodiment, the housing comprises a back cover assembled on the back side of the electronic device, and the back cover comprises the strengthened glass ceramic according to any of the embodiments of the first aspect.

[0071] As an optional embodiment, the electronic device further comprises a camera assembly inside the housing, the housing comprises a camera protective cover plate, the camera protective cover plate covers the camera assembly, and the camera protective cover plate comprises the strengthened glass ceramic according to any one of the embodiments of the first aspect.

[0072] As an optional embodiment, the electronic device further comprises a middle frame, and the middle frame comprises the strengthened glass ceramic according to any one of the embodiments of the first aspect.

[0073] In some embodiments, the housing can be partially made of the strengthened glass ceramic or entirely made of the strengthened glass ceramic. The electronic device in the present application can be one or more of a display screen cover plate, a back cover, a camera protective cover plate, and a middle frame, which are made of the strengthened glass ceramic according to any one of the embodiments of the first aspect.

[0074] In a fourth aspect, a glass device is provided, which comprises the strengthened glass ceramic according to any one of the embodiments of the first aspect.

[0075] Compared with the prior art, one or more of the above technical solutions provided in the present application have the following advantages: the present application uses a zinc aluminate-magnesium aluminate solid solution as the main crystal phase of the glass ceramic, so that the glass ceramic has high intrinsic strength. The glass ceramic with a thickness greater than 0.7 mm and containing specific contents of Li ions and Na ions is chemically strengthened, and the surface composition of the prepared strengthened glass ceramic meets specific requirements, which significantly improves the compression resistance of the strengthened glass ceramic and enables the strengthened glass ceramic to have excellent extrusion resistance. The application of the strengthened glass ceramic in electronic devices enables the electronic devices to meet the application environment with high requirements for compression resistance, such as better matching the application requirements in a water environment (such as a deep sea environment) and application in a deep water environment. BRIEF DESCRIPTION OF DRAWINGS

[0076] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed in the embodiments. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be considered as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor.

[0077] FIG. 1 is a comparison diagram of XRD patterns of the glass ceramic and the strengthened glass ceramic provided in Example 1 of the present application;

[0078] FIG. 2 is a comparison diagram of transmittance curves of the glass ceramic and the strengthened glass ceramic provided in Example 1 of the present application;

[0079] Fig. 3 is a schematic diagram of the process of single rod static pressure strength test provided by the embodiment of the present application, wherein 30 is a pressure rod, 31 is a strengthened glass ceramic sample / sheet to be tested, and 32 is a jig.

[0080] Fig. 4 is a schematic diagram of the structure of the jig used in the single rod static pressure strength test provided by the embodiment of the present application.

[0081] Fig. 5 is a schematic diagram of the cross-sectional structure of the jig used in the single rod static pressure strength test provided by the embodiment of the present application.

[0082] Fig. 6 is a topography diagram of the broken strengthened glass ceramic after the single rod static pressure strength test provided by the embodiment of the present application.

[0083] Fig. 7 is a schematic diagram of the front side structure of the electronic device mentioned in the embodiment of the present application.

[0084] Fig. 8 is a schematic diagram of the rear side structure of the electronic device mentioned in the embodiment of the present application.

[0085] Fig. 9 is a schematic diagram of the structure of the electronic device mentioned in the embodiment of the present application.

[0086] Fig. 10 is a schematic diagram of the structure of the electronic device mentioned in the embodiment of the present application.

[0087] Fig. 11 is a schematic diagram of the strengthened glass ceramic according to the embodiment of the present application; wherein t is the thickness of the glass, d is the K + diffusion depth DOL_K; 20 is a strengthened glass ceramic, 21 is a main surface of the strengthened glass ceramic, 22 is a tensile stress layer, and 23 is a compressive stress layer.

[0088] Reference signs: 1 - housing; 11 - display screen cover plate; 12 - rear cover; 13 - camera protection cover plate; 2 - camera assembly; 3 - middle frame; 4 - display module. DETAILED DESCRIPTION

[0089] The embodiments of the present application will be described in detail below with reference to the examples, but those skilled in the art will understand that the following examples are only for illustration of the present application and should not be regarded as limiting the scope of the present application. The specific conditions are not specified in the examples, and the conventional conditions or the conditions recommended by the manufacturer are used. The reagents or instruments used are not specified by the manufacturer, and are conventional products that can be purchased on the market.

[0090] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein. The terms "optional," "optional," or other similar expressions mean that they may or may not be included (or may or may not be present). The term "and / or" as used herein is inclusive; for example, "A and / or B" means only A, or only B, or both A and B.

[0091] Terminology and testing methods:

[0092] In this application, glass-ceramics are a type of solid composite material that simultaneously contains a glassy phase and a crystalline phase (or microcrystalline phase, crystalline phase, or crystal phase) prepared by targeted and controlled heat treatment of a substrate glass. Glass-ceramics are also known as microcrystalline glass, crystallized glass, or crystalline glass.

[0093] In this application, reinforced glass-ceramics refer to solid composite materials obtained by chemically strengthening glass-ceramics. It should be understood that during chemical strengthening, alkali metal ions with large ionic radii (e.g., potassium or sodium ions) in the molten salt bath (or molten salt bath) will replace alkali metal ions with small ionic radii (e.g., sodium or lithium ions) in the glass-ceramics, thereby generating a volume difference in exchange ions and producing compressive stress (or compressive stress) on the surface of the glass-ceramics.

[0094] In this application, the substrate glass refers to glass that has not undergone nucleation treatment, crystallization treatment, or strengthening treatment, or it is also called base glass.

[0095] In this application, the composition at the center of the reinforced glass ceramic refers to the composition at or near the center of the depth or thickness of the reinforced glass ceramic, that is, the composition of the region in the reinforced glass ceramic that has not undergone ion exchange. It should be understood that the composition at the center of the reinforced glass ceramic is the same as or substantially the same as the composition of the glass ceramic used to prepare the reinforced glass ceramic but which has not yet undergone chemical strengthening treatment.

[0096] In this application, the main crystalline phase (or principal crystalline phase) refers to a crystalline phase that has a higher weight content (or weight percentage, mass percentage) than other crystalline phases present in glass ceramics.

[0097] In this application, the total content of crystalline phases refers to the percentage of the total mass of crystalline phases or crystals in the glass ceramic to the mass of the glass ceramic, or the crystallinity of the glass ceramic.

[0098] In the present application, the main surface refers to the surface with the largest area, for example, the upper surface or the lower surface of a horizontally placed glass-ceramic sheet.

[0099] In the present application, the visible light wavelength range refers to 360nm-740nm.

[0100] In the present application, when light with a certain wavelength is irradiated to the main surface of a glass-ceramic, the light will be reflected, absorbed and transmitted, and the ratio of the intensity of the transmitted part to the intensity of the incident light is the transmittance.

[0101] In the present application, the nucleation treatment refers to the formation of stable crystal nuclei in the base glass through heat treatment; the crystallization treatment refers to the precipitation of crystals or crystal phases in the base glass through heat treatment.

[0102] In the present application, |CT_AV| refers to the absolute value of the average tensile stress, with the unit of MPa, and specifically refers to the absolute value of the average of all tensile stresses in the tensile stress layer, which is obtained by SLP-2000 stress meter (or also known as scatter light photoelastic stress meter).

[0103] In the present application, |CT_CV| refers to the absolute value of the maximum tensile stress, with the unit of MPa, and specifically refers to the absolute value of the maximum value of all tensile stresses in the tensile stress layer, which is obtained by SLP-2000 stress meter.

[0104] In the present application, the test method of the aforementioned stress performance is as follows: SLP 2000 stress meter is used to test |CT_CV| and |CT_AV| of the strengthened glass-ceramic. The related parameter settings of the stress meter are as follows: the wavelength of the light source is 518nm, the SOC (photoelastic coefficient) is set to 25.5 [(nm / cm) / MPa], the refractive index is set to 1.60, and the exposure time is 300μsec.

[0105] In the present application, SOC, i.e. photoelastic coefficient, photoelasticity mainly refers to the birefringence phenomenon caused by anisotropy of transparent materials after being stressed. The value of the internal residual stress of the material can be obtained by measuring the photoelastic coefficient and the birefringence.

[0106] In the present application, DOL_K refers to the depth of the K + Diffusion depth, or K + Diffusion layer depth, or K + Exchange depth, specifically refers to the depth from any main surface of the strengthened glass-ceramic to the K + Depth at which the slope value of the concentration distribution curve (or also known as K element concentration distribution curve) is equal to 0.000 for the first time, which is obtained by EPMA-1720HT electron probe EPMA. In the present application, the K + Depth at which the slope value of the concentration distribution curve (or also known as K element concentration distribution curve) is equal to 0.000 for the first time, which is obtained by EPMA-1720HT electron probe EPMA. In the present application, the K +After ion exchange, K diffuses into the surface of the glass-ceramic, and as the depth increases, K + The amount of K in the glass-ceramic decreases, and eventually, at the depth where the curve slope value is equal to 0.000 for the first time, K + No longer diffuses inward.

[0107] Electron Probe X-ray Microanalysis (EPMA) test: Take the strengthened glass-ceramic sample to be tested, mechanically grind one of the surfaces perpendicular to the main surface to remove the strengthening layer (the amount of wear removal is more than 500 μm), and prepare a cross-section sample. After grinding the cross-section, perform 30 nm carbon spraying treatment, and select a straight line in the thickness direction along the ground cross-section with a focused electron beam to perform line scanning to obtain the element composition and element concentration distribution in the thickness direction. The electron probe X-ray microanalyzer used in this application is Shimadzu EPMA-1720HT, with an acceleration voltage of 15 kV, a probe current of 100 nA, a beam size of MIN, a step interval of 1 μm, and a time of 1 s / point; spectrometer RAP (Na Kα ray) and spectrometer PET (K Kα ray); test elements: Na, K.

[0108] In this application, Vickers hardness refers to a standard for indicating material hardness proposed by Robert L. Smith and George E. Sandland of Vickers Ltd in 1921.

[0109] In this application, the test method of Vickers hardness is as follows: the glass-ceramic or strengthened glass-ceramic is made into a small disc with a diameter of 46 mm and a thickness of 0.9 mm, and a glass sample with a clean surface and no visible scratches, pits, cracks and other damage is selected as the test sample / sheet, and then a Vickers hardness tester is used to measure the Vickers hardness. The Vickers hardness tester used in this test is a digital small load Vickers hardness tester of Beijing Keweikai Technology Co., Ltd. with model number VTD405. Test conditions: load 300 gf, loading time 10 s, and the effectiveness of the indentation meets the standard of GB / T37900-2019 Ultra-thin glass hardness and fracture toughness test method Small load Vickers hardness indentation method. Select 3 different positions on the surface of the same test sample / sheet for measurement, and take the average of 3 measurement results as the Vickers hardness result of the test sample / sheet.

[0110] In the present application, the thickness of the glass-ceramics is obtained by micrometer test. It should be understood that the ion exchange degree is gradiently changed from the surface to the center in the thickness direction, and the total Na-K and / or Li-Na exchange amount increment (mass) is generally not more than 1.5% of the total mass of the sample, so the expansion effect in the thickness direction is extremely slight, and it can be approximately considered that the thickness is basically unchanged. That is, the thickness of the glass-ceramics changes very little before and after chemical strengthening, and can be basically ignored, and the thickness of the glass-ceramics is basically the same as the thickness of the strengthened glass-ceramics prepared therefrom.

[0111] In the present application, the density test adopts the electronic density balance SD-200L of Japan ALFAMIRAGE to test the density of the glass-ceramics. The measurement principle is Archimedes principle.

[0112] In the present application, the size specification of the glass-ceramics sheet is tested by a two-dimensional measuring machine (instrument model Miyu MY-YXCL-4030).

[0113] In the present application, the crystal phase composition, total crystal phase content (or also called crystallinity) and average crystal size of the glass-ceramics are confirmed by XRD test, specifically as follows:

[0114] (1) XRD test: The glass-ceramics or strengthened glass-ceramics of the present application is crushed and ground into a sample with a particle size of less than 75 μm, and the ground sample is tested by an X-ray diffractometer to obtain an XRD diffraction peak curve and XRD diffraction data. The X-ray diffractometer used in the present application is Shimadzu XRD-6100, the target material is copper, the test range is 2θ = 10°-80°, the scanning speed is 2° / min, the working voltage is 40 kV, and the working current is 30 mA.

[0115] (2) Determination of crystal phase: The XRD diffraction data is analyzed by Jade software (JADE Standard 8.6) to determine the crystal phase in the sample.

[0116] (3) Determination of total crystal phase content (or also called crystallinity): The test results of XRD (RAW format) are imported into Jade software (JADE Standard 8.6) for fitting, and the total crystal phase content of the sample can be determined by the formula (diffraction peak intensity / total intensity) x 100%.

[0117] (4) Determination of average crystal size: The average crystal size (or also referred to as average grain size) of the sample can be calculated according to the Scherrer formula D = Kλ / (βcosθ) using the data obtained from the XRD test. Wherein, λ is the X-ray wavelength, λ = 0.154056 nm, β is the half-height width of the diffraction peak, K = 0.89, and θ is the Bragg diffraction angle. Specifically, the RAW format file output by the XRD instrument is curve-fitted in the Jade software (JADE Standard 8.6), and the Jade outputs a fitting report. According to the angle 2θ value and the Peak FWHM value corresponding to each diffraction peak in the fitting report, the Peak FWHM value is converted to radians: β = (FWHM / 180 x 3.14), and the grain size of each diffraction peak is calculated by the Scherrer formula D = Kλ / (βcosθ) and then averaged to obtain the average crystal size in the sample.

[0118] In the present application, the transmittance of the glass-ceramic is tested by a spectrophotometer. Specifically, the transmittance of light of different wavelengths is tested by the spectrophotometer for 5 pieces of glass-ceramic in the same batch. The average value of the transmittance at 550 nm wavelength obtained from the 5 pieces of glass-ceramic is taken as the transmittance result of the glass-ceramic at 550 nm wavelength. The spectrophotometer used in the present application is a Konica Minolta Spectrophotometer CM-3600A made in Japan, the light receiving system is transmission, the spectrophotometer is a plane diffraction grating, the wavelength range is 360 nm-740 nm, the wavelength interval is 10 nm, the illumination light source is a pulse xenon lamp x 4, and the instrument is placed in an environment with a temperature of 24°C and an air humidity of 40%.

[0119] In the present application, the test method for the surface Na2O mass percentage (or also referred to as surface Na2O concentration) of the strengthened glass-ceramic is as follows: the Na element content in the surface of the strengthened glass-ceramic is measured by an X-ray fluorescence spectrometer (XRF), and then the surface Na2O mass percentage is calculated according to the formula: surface Na2O mass percentage = (surface Na element content x relative molecular mass of Na2O) / (relative atomic mass of Na element x 2). It should be understood that the surface Na element content = Na element mass / total element mass, and the total element mass = total oxide mass. The X-ray fluorescence spectrometer (XRF) used is a Thermo Scientific ARL PERFORM’X, the target material is Rh (rhodium), the light tube voltage is 30 kV, the current is 80 mA, the collimator is 0.40, the crystal is selected as AxO3, the detector is selected as FPC, the test range is a circle with a diameter of 29 mm, and the test method uses the X_UQ method in the OXSAS analysis software.

[0120] In the present application, the test method of the surface K2O mass percentage (or also referred to as the surface K2O concentration) of the strengthened glass ceramic is as follows: the content of K element in the surface of the strengthened glass ceramic is measured by an X-ray fluorescence spectrometer (XRF), and then the surface K2O mass percentage is calculated, and the calculation method is referred to the calculation of the surface Na2O mass percentage. The device model of the X-ray fluorescence spectrometer (XRF) used is Thermo Scientific ARL PERFORM’X, the target material is Rh (rhodium), the light tube voltage is 40 kV, the current is 60 mA, the collimator is 0.15, the crystal is selected as LiF200, the detector is selected as FPC, the test range is a circle with a diameter of 29 mm, and the test method adopts the X_UQ method in the OXSAS analysis software.

[0121] In the present application, the non-standard test is used when the XRF instrument is tested, and the concentration of elements or oxides with atomic number 6 and below in the strengthened glass ceramic is not tested. The surface K2O mass percentage of the strengthened glass ceramic = K2O mass / total mass of oxides, and the surface Na2O mass percentage of the strengthened glass ceramic = Na2O mass / total mass of oxides, wherein the oxides include SiO2, Al2O3, ZrO2, Na2O, K2O and other oxides that can be accurately tested by XRF, and do not include the content of B2O3 and other oxides that cannot be accurately tested by XRF.

[0122] In the present application, when the XRF instrument is used for testing, the strengthened glass ceramic sheet is directly cut into a suitable size (such as 34 mm*34 mm), placed flat in the sample box, and covered with the test aperture for testing.

[0123] In the present application, the test of fracture toughness: the test is carried out according to the standard of “GB / T 37900-2019 Ultra-thin glass hardness and fracture toughness test method small load Vickers hardness indentation method”.

[0124] Specifically, the indentation is prepared by the same method as measuring the Vickers hardness, the crack length 2C1, 2C2 in the diagonal direction of the indentation is measured, and the maximum value cannot exceed the thickness of the glass. At least 5 effective indentation morphologies are measured on one sample surface, and the average value is calculated as the final result value of the sample.

[0125] Indentation fracture toughness calculation formula:

[0126] Wherein, IFR: indentation fracture toughness, unit: megapascal and one half of the square meter (MPa·m 0.5) ; E: elastic modulus of the sample, unit: gigapascal (GPa) ; 2C1, 2C2: crack propagation length in the diagonal direction of the indentation, unit: millimeter (mm), d1, d2: diagonal length of the indentation, unit: millimeter (mm), F: test load value, unit: newton (N).

[0127] In the present application, the single rod static pressure strength test: the strengthened glass ceramic sample to be tested is placed in the customized jig (as shown in FIG. 3), and then placed on the bottom ring of the tensile testing machine (LT-850A), the test software is started, the moving speed of the extrusion rod (rod diameter 10mm, ball head diameter 10mm) is set to 10mm / min, the start test is clicked, the extrusion rod will apply force to the center of the strengthened glass ceramic sample to be tested at the set moving speed until the strengthened glass ceramic sample is broken, and the test process is shown in FIG. 3.

[0128] The test software will automatically read the force (N) when the strengthened glass ceramic sample is broken, which is recorded as the single rod static pressure strength it can withstand. Take 10 pieces of strengthened glass ceramic samples of the same batch for testing, and take the average value of the test results as the single rod static pressure strength of the strengthened glass ceramic sample to be tested.

[0129] The customized jig in the present test method is a cylindrical jig with a diameter of 65mm and a height of 20mm, and the specific structure of the customized jig is shown in FIG. 4 and FIG. 5, wherein Φ1=65mm, Φ2=46.02mm, Φ3=44mm, h1=20mm, h2=the thickness of the strengthened glass ceramic sample to be tested, and h3=15mm. The height h2 of the sample slot in the customized jig is equal to the thickness of the strengthened glass ceramic sample to be tested, and the strengthened glass ceramic sample to be tested can be placed in the jig. The stepped blind hole for placing the sample for testing in the customized jig is coaxial with the customized jig. The material of the jig is acrylic material.

[0130] Although the current glass ceramic has better performance than general glass, its compression resistance still needs to be further improved.

[0131] Without being limited by any theory, spinel crystals have excellent properties such as high hardness and high modulus, and the use of glass ceramics with spinel crystal phase as the main crystal phase for chemical strengthening to prepare strengthened glass ceramics is more conducive to obtaining strengthened glass ceramic materials with excellent extrusion resistance than the use of ordinary glass.

[0132] The general chemical formula of spinel crystals is AB₂O₄, where A is a divalent metal ion such as Zn, Fe, or Mg with tetrahedral coordination, and B is a metal ion such as Al, Cr, or Fe with octahedral coordination. Because Al-O, Mg-O, and Zn-O can all form strong ionic bonds, spinel has a robust structure, high hardness, and stable chemical properties. The Mohs hardness of spinel crystals is generally between 7 and 8, close to 8. Therefore, theoretically, by controllably precipitating zinc spinel (or zinc-aluminum spinel) and / or magnesium spinel (or magnesium-aluminum spinel) and / or zinc-magnesium spinel solid solution (Zn,Mg)Al₂O₄ in glass, spinel glass ceramics with excellent mechanical properties can be obtained.

[0133] Therefore, this application employs a glass-ceramic containing spinel crystals that meets specific composition and structure requirements to prepare a reinforced glass-ceramic material with desired compressive strength. The glass-ceramic used in this application is rich in high-strength spinel crystals and possesses a high-strength glass phase structure. Through the synergistic effect of the crystal phase structure and the glass phase structure, the glass-ceramic is endowed with high inherent strength or intrinsic strength. This application further enhances the glass-ceramic by chemically strengthening its surface composition to meet specific requirements, thereby endowing the resulting reinforced glass-ceramic with a stress structure and stress level that achieves high compressive strength, thus obtaining a reinforced glass-ceramic with excellent compressive strength.

[0134] Understandably, "surface composition" in this application can refer to the material composition or component distribution of the surface of the substrate glass, glass ceramic, or reinforced glass ceramic. It can also refer to the mass percentage, molar percentage, mass percentage relationship between two or more material components, mass content relationship between two or more material components, molar content relationship between two or more material components, a combination of the foregoing, and others. For example: the mass percentage of Na2O or K2O on the surface of reinforced glass ceramic; or the mass percentage of Na2O and K2O on the surface of reinforced glass ceramic; or the K2O content calculated from the main surface of the reinforced glass ceramic. + (K element) diffusion depth.

[0135] In some embodiments of this application, a reinforced glass ceramic is provided, wherein the reinforced glass ceramic is plate-shaped, and the thickness t of the reinforced glass ceramic is greater than 0.7 mm, preferably not less than 0.8 mm, and more preferably not less than 0.9 mm.

[0136] The strengthened glass ceramic contains a main crystal phase of a zinc aluminate-magnesium aluminate spinel solid solution and a secondary crystal phase of zirconia; the strengthened glass ceramic has a compressive stress layer on the surface and a tensile stress layer in the interior;

[0137] The strengthened glass ceramic contains Li2O and Na2O at the center or in the composition of the tensile stress layer, and the mass percentage of Li2O is greater than 1.00%, preferably greater than 1.30%, more preferably greater than or equal to 1.50%, and the mass percentage of Na2O is greater than 1.00%, preferably greater than 2.00%, more preferably greater than 2.70%, in terms of mass percentage of oxides;

[0138] The surface K2O mass percentage of the strengthened glass ceramic is 2.00% to 7.50%, preferably 2.50% to 6.50%, more preferably 3.00% to 6.00%, in terms of mass percentage of oxides, as determined by XRF;

[0139] The surface Na2O mass percentage of the strengthened glass ceramic is less than or equal to 0.010%, preferably less than or equal to 0.005%, more preferably less than or equal to 0.002%, in terms of mass percentage of oxides, as determined by XRF;

[0140] The strengthened glass ceramic satisfies 5.00 μm ≤ DOL_K ≤ 20.00 μm, preferably 5.50 μm ≤ DOL_K ≤ 18.00 μm, more preferably 6.00 μm ≤ DOL_K ≤ 16.00 μm, as determined by EPMA, where DOL_K is the K + Diffusion depth.

[0141] In the present application, by simultaneously containing a certain amount of Li2O and Na2O in the glass ceramic, not only can the fracture toughness of the glass ceramic be increased, the overall strength of the glass phase (or also known as residual glass phase) can be improved, so that it is not easy to break when subjected to extrusion or impact, but also the chemical strengthening effect of the glass ceramic can be improved.

[0142] The present application uses zinc aluminate-magnesium aluminate solid solution as the main crystal phase of the glass ceramic, so that the glass ceramic has high intrinsic strength. The glass ceramic with a thickness greater than 0.7 mm and containing specific contents of Li ions and Na ions is chemically strengthened, and the surface composition of the prepared strengthened glass ceramic meets specific requirements, which significantly improves the compressive capacity of the strengthened glass ceramic and makes the strengthened glass ceramic have excellent extrusion resistance. In the present application, (Zn, Mg)Al2O4 represents zinc aluminate-magnesium aluminate solid solution (or also known as zinc magnesium spinel solid solution, zinc spinel-magnesium spinel solid solution, zinc magnesium aluminate spinel solid solution). The application of the strengthened glass ceramic in electronic devices enables the electronic devices to meet the application environment with high requirements for compressive capacity, such as better matching the application requirements in water environment (such as deep sea environment), and can be applied in deep water environment.

[0143] In some embodiments, the surface K2O mass percentage of the strengthened glass ceramic can be 3.20% to 5.80%, 3.80% to 5.60%, or 4.10% to 5.5%. In some embodiments, the surface K2O mass percentage of the strengthened glass ceramic can be 2.00%, 2.50%, 3.00%, 3.50%, 4.00%, 4.50%, 5.00%, 5.50%, 6.00%, 6.50%, 7.00%, 7.50%, 3.91%, 4.16%, 3.96%, 4.12%, 4.53%, 3.24%, 4.55%, 4.51%, 4.68%, 5.75%, 3.85%, 4.48%, 5.69%, 5.45%, 5.57%, or 5.54%, or a value within a range having any two of the above specifically stated values as endpoints, as long as the strengthened glass ceramic having the desired properties of the present application is obtained. It should be understood that in specific embodiments, any of the above ranges can be combined with any other range, as long as the strengthened glass ceramic having the desired properties of the present application is obtained.

[0144] In some embodiments, the surface Na2O mass percentage of the strengthened glass ceramic can be 0.000%, 0.002%, 0.003%, 0.004%, 0.005%, 0.006%, 0.007%, 0.008%, 0.009%, or 0.010%, or a value within a range having any two of the above specifically stated values as endpoints, as long as the strengthened glass ceramic having the desired properties of the present application is obtained. It should be understood that in specific embodiments, any of the above ranges can be combined with any other range, as long as the strengthened glass ceramic having the desired properties of the present application is obtained.

[0145] In some embodiments, the strengthened glass-ceramic can have a DOL K that satisfies 10.00 pm < DOL K < 17.00 pm, 5.00 pm < DOL K < 10.00 pm, 17.00 pm < DOL K < 20.00 pm, 11.00 pm < DOL K < 15.00 pm, 12.00 pm < DOL K < 14.00 pm, or 12.00 pm < DOL K < 13.00 pm. In some embodiments, the strengthened glass-ceramic can have a DOL K of 5.00 pm, 5.50 pm, 6.00 pm, 6.50 pm, 7.00 pm, 7.50 pm, 8.00 pm, 8.50 pm, 9.00 pm, 9.50 pm, 10.00 pm, 10.50 pm, 11.00 pm, 11.50 pm, 12.00 pm, 12.50 pm, 13.00 pm, 13.50 pm, 14.00 pm, 14.50 pm, 15.00 pm, 15.50 pm, 16.00 pm, 16.50 pm, 17.00 pm, 17.50 pm, 18.00 pm, 18.50 pm, 19.00 pm, 19.50 pm, 20.00 pm, 7.70 pm, 9.60 pm, 10.30 pm, 8.40 pm, 10.40 pm, 8.60 pm, 14.10 pm, 12.50 pm, 6.20 pm, 9.80 pm, 12.80 pm, 9.10 pm, 8.30 pm, 8.80 pm, 11.40 pm, 12.80 pm, 10.60 pm, 11.80 pm, or 11.70 pm, or a value within a range between any two of the specifically recited values, as long as the strengthened glass-ceramic has the desired properties. It should be understood that any of the above ranges can be combined with any other range, as long as the strengthened glass-ceramic has the desired properties.

[0146] In some embodiments, the strengthened glass-ceramics can have a thickness t of not less than 0.95 mm, not less than 1.00 mm, not less than 1.05 mm, 0.85 mm to 2.00 mm, or 0.90 mm to 1.50 mm. The thickness of the strengthened glass-ceramics is positively correlated with the extrusion resistance of the strengthened glass-ceramics. The thicker the strengthened glass-ceramics, the better the extrusion resistance. When the thickness of the strengthened glass-ceramics is small, the extrusion resistance is significantly reduced. By controlling the thickness of the strengthened glass-ceramics to be not less than 0.70 mm, the strengthened glass-ceramics has good extrusion resistance. When the thickness of the strengthened glass-ceramics is too large, on the one hand, the weight is increased, which is not conducive to the lightness and thinness of electronic devices. On the other hand, the transmittance of the glass-ceramics is reduced, and the light transmittance is poor. In some embodiments, the thickness of the strengthened glass-ceramics of the present application can be 0.80 mm, 0.85 mm, 0.90 mm, 1.00 mm, 1.10 mm, 1.20 mm, 1.30 mm, 1.40 mm, or 1.50 mm, or a value within a range formed by any two of the above specific values as endpoints, as long as the strengthened glass-ceramics with the required performance of the present application can be obtained. It should be understood that in specific embodiments, any of the above ranges can be combined with any other range, as long as the strengthened glass-ceramics with the required performance of the present application can be obtained.

[0147] In some embodiments of the present application, the strengthened glass-ceramics or the glass-ceramics for preparing the strengthened glass-ceramics are 2D, 2.5D, 3D or irregular shaped, i.e., the glass-ceramics can be a 2D, 2.5D, 3D or irregular shaped article, and the strengthened glass-ceramics can also be a 2D, 2.5D, 3D or irregular shaped article; and / or, the strengthened glass-ceramics or the glass-ceramics for preparing the strengthened glass-ceramics are of equal thickness or unequal thickness. "Unequal thickness" means that the strengthened glass-ceramics or the glass-ceramics for preparing the strengthened glass-ceramics comprises at least two portions with different thicknesses.

[0148] In some embodiments of the present application, the strengthened glass-ceramics satisfies: along the thickness direction of the strengthened glass-ceramics, the concentration of K element shows a nonlinear decreasing trend from the main surface of the strengthened glass-ceramics to the center of the strengthened glass-ceramics, as tested by EPMA. In the present application, the K + concentration distribution curve of the strengthened glass-ceramics from the main surface to the interior of the strengthened glass-ceramics measured by EPMA shows a nonlinear decreasing trend. + The K + element diffuses into the surface of the glass-ceramics after ion exchange, and the amount of K + element in the glass-ceramics decreases with the increase of the depth, and finally, when the depth at which the curve slope value is equal to 0.000 for the first time, the K + element no longer diffuses inward.

[0149] It is understood that, unless over-ion exchange is performed, the composition and phase assembly at the depth of the compressive stress layer (DOL) or at the center of the strengthened glass-ceramics or the tensile stress layer is the same or substantially the same as that of the glass-ceramics.

[0150] It is understood that the strengthened glass-ceramics of the present application are made from a glass-ceramics that is chemically strengthened, and the composition at the center of the strengthened glass-ceramics or the tensile stress layer is the same or substantially the same as that of the glass-ceramics. The composition at the surface of the glass-ceramics article after the chemical strengthening process can be different from that of the glass-ceramics before the chemical strengthening process, because, during the chemical strengthening process, one type of alkali metal ions (e.g., Li + or Na + ) at the surface of the glass-ceramics is replaced by a larger alkali metal ion (e.g., Na + or K + ), respectively. However, in embodiments, the glass composition and phase assembly at or near the center of the depth or thickness of the glass-ceramics article is the same as that of the as-formed glass-ceramics. That is, in the present application, the composition at the center of the strengthened glass-ceramics or the tensile stress layer is the same or substantially the same as that of the glass-ceramics that is not chemically strengthened.

[0151] Meanwhile, in the present application, the glass-ceramics used to make the strengthened glass-ceramics can be made from a base glass that is heat treated, and the composition of the base glass is the same or substantially the same as that of the glass-ceramics, in terms of mass percent of oxides.

[0152] In some embodiments of the present application, the composition at the center of the strengthened glass-ceramics or the tensile stress layer or the composition of the glass-ceramics used to make the strengthened glass-ceramics or the composition of the base glass comprises Al2O3in an amount of greater than or equal to 30.00% in terms of mass percent of oxides.

[0153] In the present application, by controlling the mass percentage of Al2O3 in the glass-ceramic to be greater than or equal to 30%, on the one hand, the desired content of main crystal phase can be precipitated, so that the glass-ceramic obtains high intrinsic strength (or also known as inherent strength), on the other hand, a certain amount of alumina can also be contained in the glass phase, and the alumina existing in the glass phase can enter the glass network structure in the form of [AlO4] tetrahedron, form a unified grid with [SiO4], and enhance the connection degree of the network, improve the strength and stability of the glass network structure, thereby further improving the intrinsic strength of the glass-ceramic. At the same time, the [AlO4] tetrahedron in the glass phase can appropriately expand the ion exchange channel, improve the chemical strengthening effect of the glass-ceramic, and be more conducive to obtaining a strengthened glass-ceramic with excellent mechanical strength performance.

[0154] In some embodiments of the present application, the composition at the center of the strengthened glass-ceramic or the composition of the glass-ceramic for preparing the strengthened glass-ceramic or the composition of the substrate glass comprises ZrO2 with a mass percentage of greater than or equal to 3.00% in terms of mass percentage of oxides.

[0155] In the present application, by controlling the mass percentage of zirconia in the glass-ceramic to be greater than or equal to 3.00%, the intrinsic strength of the glass-ceramic is improved, and the surface stress level of the strengthened glass-ceramic prepared therefrom is improved. On the one hand, as a nucleating agent, zirconia will disperse in the glass phase in the form of nanoscale grains after heat treatment, which can increase the hardness of the glass-ceramic, thereby effectively improving the shatter resistance of the glass-ceramic. On the other hand, zirconia exists in the glass phase in the form of [ZrO8] cube, which can enhance the interionic force and make the glass structure more compact, thereby being conducive to improving the mechanical strength of the glass phase. At the same time, zirconia can significantly improve the surface compressive stress formed by ion exchange, thereby improving the surface stress level of the strengthened glass-ceramic prepared therefrom.

[0156] In some embodiments of the present application, the composition at the center of the strengthened glass-ceramic or the composition of the glass-ceramic for preparing the strengthened glass-ceramic or the composition of the substrate glass comprises:

[0157] SiO2: 25.00% to 55.00%, Al2O3: 30.00% to 55.00%, ZrO2: 3.00% to 8.00%, MgO: 2.00% to 5.00%, ZnO: 5.00% to 15.00%, Na2O: 1.00% to 10.00%, K2O: 0% to 5.00%, Li2O: 1.00% to 6.00%, CaO: 0% to 6.00%, B2O3: 0% to 10.00%, BaO: 0% to 10.00%, Y2O3: 0% to 6.00%, La2O3: 0% to 12.00%. By adjusting and controlling the content range of each oxide component, it is beneficial to ensure that the strengthened glass-ceramic satisfying the desired crystal phase structure is obtained, and it is also beneficial to ensure that the strengthened glass-ceramic obtains excellent optical performance and high intrinsic strength. It should be understood that in specific embodiments, any of the above ranges can be combined with any other range, as long as the glass-ceramic or strengthened glass-ceramic with the desired properties of the present application can be obtained.

[0158] In the present application, SiO2 is a network former oxide of glass network, which is an indispensable component of the glass network structure. Increasing the content of SiO2 can increase the stability and mechanical strength of the glass, but excessive SiO2 will increase the viscosity of the substrate glass, making it difficult to melt the glass, thereby reducing the formability of the substrate glass. In the present application, the mass percentage of SiO2 in the composition of the center of the strengthened glass-ceramic or the composition of the tensile stress layer of the strengthened glass-ceramic or the composition of the glass-ceramic used to prepare the strengthened glass-ceramic or the composition of the substrate glass is 25.00% to 55.00%, preferably 30.00% to 42.00%, and more preferably 35.00% to 40.00%.

[0159] In some embodiments of the present application, the content of Si02in the composition at the center of the strengthened glass-ceramic or the composition of the strengthened glass-ceramic or the composition of the glass-ceramic used to make the strengthened glass-ceramic or the composition of the base glass can be in the range of 25.00% to 55.00%, 25.00% to 40.00%, 40.00% to 55.00%, or 30.00% to 40.00% by mass percent of oxides. In some embodiments of the present application, the content of Si02in the composition at the center of the strengthened glass-ceramic or the composition of the strengthened glass-ceramic or the composition of the glass-ceramic used to make the strengthened glass-ceramic or the composition of the base glass can be 25.00%, 26.00%, 27.00%, 28.00%, 29.00%, 30.00%, 31.00%, 32.00%, 33.00%, 34.00%, 35.00%, 35.50%, 36.00%, 37.00%, 38.00%, 39.00%, 40.00%, 41.00%, 42.00%, 43.00%, 44.00%, 45.00%, 46.00%, 47.00%, 48.00%, 49.00%, 50.00%, 51.00%, 52.00%, 53.00%, 54.00%, 55.00%, 37.08%, 36.87%, 33.23%, 37.43%, 37.40%, 38.33%, 36.05%, 35.67%, 32.39%, 37.50%, 35.64%, 37.32%, or 36.31% by mass percent of oxides, or a value within a range having any two of the above specific numeric values as endpoints, as long as a glass-ceramic or strengthened glass-ceramic having the desired properties of the present application is obtained. It is to be understood that in specific embodiments, any of the above ranges can be combined with any of the other ranges, as long as a glass-ceramic or strengthened glass-ceramic having the desired properties of the present application is obtained.

[0160] In the present application, Al2O3 is one of the components of the main crystal phase of zinc magnesium spinel solid solution crystal phase formed after the crystallization of the substrate glass, the increase of Al2O3 can promote the precipitation of spinel and inhibit the precipitation of other impurities such as quartz, which will directly affect the content of the main crystal phase (Zn, Mg) Al2O4, with the increase of the content of Al2O3, the strength of the glass phase in the glass-ceramics is also enhanced, and the mechanical properties of the glass-ceramics are enhanced. At the same time, since the volume of [AlO4] is larger than that of [SiO4], it can provide more space for ion exchange, which is beneficial to promote the chemical strengthening. However, excessive Al2O3 will increase the viscosity of the substrate glass, which will reduce the formability of the substrate glass, and at the same time, it is easy to cause the crystallization rate to be too fast, which will cause the substrate glass to lose transparency during normal cooling process. In the present application, the mass percentage of Al2O3 in the composition of the center or the tensile stress layer of the strengthened glass-ceramics, or the composition of the glass-ceramics for preparing the strengthened glass-ceramics, or the composition of the substrate glass is 30.00% to 55.00%, preferably 32.00% to 42.00%, more preferably 34.00% to 42.00%.

[0161] In some embodiments of the present application, the content of Al2O3 in the composition of the center of the strengthened glass ceramic or the composition of the tension stress layer or the composition of the glass ceramic used to prepare the strengthened glass ceramic or the composition of the base glass can be 30.00% to 55.00%, 30.00% to 40.00%, or 40.00% to 55.00% by mass percent of oxide. In some embodiments of the present application, the content of Al2O3 in the composition of the center of the strengthened glass ceramic or the composition of the tension stress layer or the composition of the glass ceramic used to prepare the strengthened glass ceramic or the composition of the base glass can be 30.00%, 31.00%, 32.00%, 33.00%, 34.00%, 34.50%, 35.00%, 35.50%, 36.00%, 36.50%, 37.00%, 38.00%, 39.00%, 40.00%, 41.00%, 42.00%, 43.00%, 44.00%, 45.00%, 46.00%, 47.00%, 48.00%, 49.00%, 50.00%, 51.00%, 52.00%, 53.00%, 54.00%, 54.50%, 55.00%, 35.83%, 36.98%, 36.27%, 37.52%, 36.60%, 37.07%, 34.84%, 34.55%, 35.88%, 38.63%, 36.23%, or 35.10% by mass percent of oxide, or a value within a range defined by any two of the above specific values as endpoints, as long as a glass ceramic or strengthened glass ceramic with desired properties of the present application can be obtained. It should be understood that in specific embodiments, any of the above ranges can be combined with any other range, as long as a glass ceramic or strengthened glass ceramic with desired properties of the present application can be obtained.

[0162] In the present application, ZrO2 is an effective nucleating agent, which is precipitated in the form of crystals during heat treatment of the glass, and the ZrO2 crystals become crystal nuclei for subsequent crystal growth. Within a certain range of glass composition, the content of ZrO2 affects the formation of the glass, the crystal shape, the crystal type, and the crystal size of the glass ceramic obtained after heat treatment of the glass, etc. By adjusting the composition of the glass, ZrO2 can be precipitated preferentially at the same temperature, followed by the growth of the main spinel crystal phase. When the content of ZrO2 is too low, it will affect the precipitation of the main crystal phase of the zinc-magnesium spinel solid solution; when the content of ZrO2 is too high, it will make the melting of the base glass more difficult, resulting in white unmelted substances in the base glass. In the present application, the mass percent of ZrO2 in the composition of the center of the strengthened glass ceramic or the composition of the tension stress layer or the composition of the glass ceramic used to prepare the strengthened glass ceramic or the composition of the base glass is 3.00% to 8.00%, preferably 4.00% to 7.00%, and more preferably 5.00% to 6.00%.

[0163] In some embodiments of the present application, the content of Zr02in the composition of the center of the strengthened glass-ceramic or the composition of the tensile stress layer or the composition of the glass-ceramic used to prepare the strengthened glass-ceramic or the composition of the base glass can be 3.00% to 8.00%, 3.00% to 6.00%, or 6.00% to 8.00% by mass percent of oxide. In some embodiments of the present application, the content of Zr02in the composition of the center of the strengthened glass-ceramic or the composition of the tensile stress layer or the composition of the glass-ceramic used to prepare the strengthened glass-ceramic or the composition of the base glass can be 3.00%, 3.20%, 3.50%, 3.70%, 4.00%, 4.20%, 4.50%, 4.70%, 5.00%, 5.20%, 5.50%, 5.70%, 6.00%, 6.50%, 7.00%, 7.50%, 8.00%, 5.69%, 5.65%, 5.61%, 5.74%, 5.81%, 5.89%, 5.54%, 5.48%, 5.76%, 5.72%, 5.99%, or 5.58% by mass percent of oxide, or a value within a range defined by any two of the above specific values as endpoints, as long as a glass-ceramic or strengthened glass-ceramic having the desired properties of the present application is obtained. It should be understood that any of the above ranges can be combined with any other range, as long as a glass-ceramic or strengthened glass-ceramic having the desired properties of the present application is obtained.

[0164] In the present application, ZnO provides the zinc necessary for the formation of the main crystal phase of the zinc-magnesium spinel solid solution crystal phase after crystallization of the base glass. ZnO can reduce the thermal expansion coefficient of the glass, improve the chemical stability, thermal stability, and refractive index of the glass. MgO provides the magnesium necessary for the formation of the main crystal phase of the zinc-magnesium spinel solid solution crystal phase after crystallization of the base glass. MgO can slow the hardening rate of the glass, improve the forming properties of the glass; MgO can also reduce the crystallization tendency and crystallization rate, increase the high temperature viscosity of the glass, and improve the chemical stability and mechanical strength of the glass. However, the addition of excessive amounts of MgO and ZnO often easily leads to excessively large spinel grains, and it is difficult to obtain a glass-ceramic with high transparency. In the present application, the mass percent of ZnO in the composition of the center of the strengthened glass-ceramic or the composition of the tensile stress layer or the composition of the glass-ceramic used to prepare the strengthened glass-ceramic or the composition of the base glass is 5.00% to 15.00%, preferably 9.00% to 13.00%, and more preferably 9.00% to 11.00%; the mass percent of MgO is 2.00% to 5.00%, preferably 2.50% to 4.00%, and more preferably 2.50% to 3.50%.

[0165] In some embodiments of the present application, the content of ZnO in the composition at the center of the strengthened glass-ceramic or the composition of the strengthened glass-ceramic or the composition of the glass-ceramic used to make the strengthened glass-ceramic or the composition of the substrate glass can be 5.00%, 5.50%, 6.00%, 6.50%, 7.00%, 7.50%, 8.00%, 8.50%, 9.00%, 9.50%, 10.00%, 10.50%, 11.00%, 11.50%, 12.00%, 12.50%, 13.00%, 10.77%, 10.71%, 10.55%, 10.87%, 11.01%, 11.15%, 10.46%, 10.37%, 12.50%, 10.82%, 11.33%, or 10.54% in mass percent of oxide, or a value within a range defined by any two of the above specific values as endpoints, as long as a glass-ceramic or strengthened glass-ceramic with the desired properties of the present application is obtained. It is understood that in specific embodiments, any of the above ranges can be combined with any of the other ranges, as long as a glass-ceramic or strengthened glass-ceramic with the desired properties of the present application is obtained.

[0166] In some embodiments of the present application, the content of MgO in the composition at the center of the strengthened glass-ceramic or the composition of the strengthened glass-ceramic or the composition of the glass-ceramic used to make the strengthened glass-ceramic or the composition of the substrate glass can be 2.00%, 2.50%, 3.00%, 3.50%, 4.00%, 4.50%, 5.00%, 2.98%, 3.04%, 3.03%, 3.06%, 3.10%, 2.92%, 2.89%, 3.01%, 3.27%, or 2.94% in mass percent of oxide, or a value within a range defined by any two of the above specific values as endpoints, as long as a glass-ceramic or strengthened glass-ceramic with the desired properties of the present application is obtained. It is understood that in specific embodiments, any of the above ranges can be combined with any of the other ranges, as long as a glass-ceramic or strengthened glass-ceramic with the desired properties of the present application is obtained.

[0167] In the present application, the increase of Na2O content helps to obtain higher surface compressive stress, while the melting temperature and the temperature of crystal precipitation can be reduced. However, excessive addition of Na2O can lead to ceramming of the glass during annealing, or lead to precipitation of other phases affecting the transmittance of the glass ceramic during heat treatment, thus resulting in a decrease of the transmittance of the obtained glass ceramic. Too low Na2O content can lead to an increase of the heat treatment temperature, direct phase separation or precipitation of impurity phases during heat treatment, thus resulting in a glass ceramic with poor transparency or opaque. In the present application, the mass percentage of Na2O in the composition of the center of the strengthened glass ceramic or the tensile stress layer, or the composition of the glass ceramic used to prepare the strengthened glass ceramic, or the composition of the base glass is 1.00% to 10.00%, preferably 1.00% to 8.00%, more preferably 2.00% to 6.00%.

[0168] In some embodiments of the present application, the content of Na2O in the composition of the center of the strengthened glass ceramic or the tensile stress layer, or the composition of the glass ceramic used to prepare the strengthened glass ceramic, or the composition of the base glass can be 1.00%, 1.50%, 2.00%, 2.50%, 3.00%, 3.50%, 4.00%, 4.50%, 5.00%, 5.50%, 6.00%, 6.50%, 7.00%, 7.50%, 8.00%, 8.50%, 9.00%, 9.50%, 10.00%, 2.86%, 2.85%, 2.89%, 3.00%, 1.69%, 2.79%, 2.76%, 3.31%, 4.61%, 3.01% or 8.00%, or can be a value within a range formed by any two of the above specific values as endpoints, as long as a glass ceramic or a strengthened glass ceramic with the desired properties of the present application can be obtained. It should be understood that in specific embodiments, any of the above ranges can be combined with any other range, as long as a glass ceramic or a strengthened glass ceramic with the desired properties of the present application can be obtained.

[0169] In the present application, Li2O helps to obtain higher compressive stress layer depth, increase Young's modulus and fracture toughness; while the melting temperature and the temperature of crystal precipitation can be reduced. However, excessive addition of Li2O can lead to ceramming of the glass during annealing, or lead to precipitation of other phases affecting the transmittance of the glass ceramic during heat treatment, or lead to excessive growth of crystals during heat treatment, thus resulting in a decrease of the transmittance of the obtained glass ceramic. Too low Li2O content can lead to an increase of the heat treatment temperature and a decrease of the deep stress. In the present application, the mass percentage of Li2O in the composition of the center of the strengthened glass ceramic or the tensile stress layer, or the composition of the glass ceramic used to prepare the strengthened glass ceramic, or the composition of the base glass is 1.00% to 6.00%, preferably 1.00% to 4.00%, more preferably 2.00% to 3.00%.

[0170] In some embodiments of the application, the content of Li20 in the composition of the strengthened glass-ceramic at the center or the composition of the compressive stress layer or the composition of the glass-ceramic used to prepare the strengthened glass-ceramic or the base glass can be 1.00%, 1.50%, 2.00%, 2.50%, 3.00%, 3.50%, 4.00%, 4.50%, 5.00%, 5.50%, 6.00%, 2.35%, 1.55%, 1.50%, 1.77%, 1.60%, 1.62%, 2.28%, 2.27%, 2.24%, 1.60%, 1.57%, 2.85%, or 1.53%, or a value within a range defined by any two of the above specific values as endpoints, as long as a glass-ceramic or strengthened glass-ceramic with desired properties of the application can be obtained. It should be understood that in specific embodiments, any of the above ranges can be combined with any other range, as long as a glass-ceramic or strengthened glass-ceramic with desired properties of the application can be obtained.

[0171] In the present application, K20 can be added as an optional component in an amount of 0-5.00% by mass, preferably 0-3.00%, and more preferably 0-1.00%. In some embodiments, it is preferred that the composition of the strengthened glass-ceramic at the center or the composition of the compressive stress layer or the composition of the glass-ceramic used to prepare the strengthened glass-ceramic or the base glass does not contain K20.

[0172] In the present application, CaO can be added as an optional component in an appropriate amount to reduce the viscosity of the glass, improve the formability, strain point and Young's modulus of the base glass, and improve the ion exchange capacity, while calcium oxide can also increase the gloss and transparency of the glass, reduce the tendency of the glass to crystallize, and slow down the hardening speed of the glass. However, when the content of CaO is too high, the density and CTE of the glass composition will increase, and the ion exchange performance of the glass-ceramic will be significantly reduced. In the present application, the content of CaO in the composition of the strengthened glass-ceramic at the center or the composition of the compressive stress layer or the composition of the glass-ceramic used to prepare the strengthened glass-ceramic or the base glass is 0%-6.00% by mass, preferably 0%-3.00%, and more preferably 0%-1.50%.

[0173] In some embodiments of the present application, the content of CaO in the composition of the center of the strengthened glass-ceramics or the composition of the tension stress layer or the composition of the glass-ceramics used to prepare the strengthened glass-ceramics or the composition of the base glass can be 0%, 0.50%, 1.00%, 1.50%, 2.00%, 2.50%, 3.00%, 3.50%, 4.00%, 4.50%, 5.00%, 5.50%, 6.00%, 0.75%, 1.15%, or 0.92% in terms of mass percentage of oxide, or can be a value within a value range consisting of any two of the above specific numerical values as endpoints, as long as a glass-ceramics or strengthened glass-ceramics with the required properties of the present application can be obtained. It should be understood that in specific embodiments, any of the above ranges can be combined with any other range, as long as a glass-ceramics or strengthened glass-ceramics with the required properties of the present application can be obtained.

[0174] In the present application, B2O3 is an optional component. An appropriate amount of B2O3 is beneficial to greatly reduce the melting difficulty of the glass and promote the precipitation of spinel. However, an excessive amount of B2O3 will cause opalescence during heat treatment of the base glass to prepare the glass-ceramics, and may also cause the precipitation of other crystal phases that seriously affect the transparency of the glass. In the present application, the mass percentage of B2O3 in the composition of the center of the strengthened glass-ceramics or the composition of the tension stress layer or the composition of the glass-ceramics used to prepare the strengthened glass-ceramics or the composition of the base glass is 0% to 10.00%, preferably 0% to 8.00%, and more preferably 0% to 4.00%.

[0175] In some embodiments of the present application, the content of B2O3 in the composition of the center of the strengthened glass-ceramics or the composition of the tension stress layer or the composition of the glass-ceramics used to prepare the strengthened glass-ceramics or the composition of the base glass can be 0%, 0.50%, 1.00%, 1.50%, 2.00%, 2.50%, 3.00%, 3.50%, 4.00%, 4.50%, 5.00%, 6.00%, 7.00%, 8.00%, 9.00%, 10.00%, or 7.07% in terms of mass percentage of oxide, or can be a value within a value range consisting of any two of the above specific numerical values as endpoints, as long as a glass-ceramics or strengthened glass-ceramics with the required properties of the present application can be obtained. It should be understood that in specific embodiments, any of the above ranges can be combined with any other range, as long as a glass-ceramics or strengthened glass-ceramics with the required properties of the present application can be obtained.

[0176] In the present application, BaO is an optional component. A proper amount of BaO is beneficial to improve the melting effect of the glass, increase the density of the glass, improve the Young's modulus, and to a certain extent, inhibit the growth of the crystal grains and improve the optical performance of the glass-ceramics. However, too much BaO has a strong inhibitory effect on the exchange process of Na ions and K ions. In the present application, the mass percentage of BaO in the composition of the center of the strengthened glass-ceramics or the composition of the tensile stress layer or the composition of the glass-ceramics used for preparing the strengthened glass-ceramics or the composition of the base glass is 0% to 10.00%, preferably 0% to 7.00%, and more preferably 0% to 4.00%.

[0177] In some embodiments of the present application, the content of BaO in the composition of the center of the strengthened glass-ceramics or the composition of the tensile stress layer or the composition of the glass-ceramics used for preparing the strengthened glass-ceramics or the composition of the base glass is 0%, 0.50%, 1.00%, 1.50%, 2.00%, 2.50%, 3.00%, 3.50%, 4.00%, 4.50%, 5.00%, 6.00%, 7.00%, 8.00%, 9.00%, 10.00%, 2.42%, 2.41%, 6.94%, 2.35%, or 2.32% in terms of mass percentage of oxide, or can be a value within a value range formed by any two of the above specific values as endpoints, as long as a glass-ceramics or a strengthened glass-ceramics with the required performance of the present application can be obtained. It should be understood that in specific embodiments, any of the above ranges can be combined with any other range, as long as a glass-ceramics or a strengthened glass-ceramics with the required performance of the present application can be obtained.

[0178] In the present application, Y2O3 has the effect of making the glass structure compact. A proper amount of Y2O3 can increase the packing density inside the glass, which is manifested as an increase in the density of the glass, thereby facilitating the improvement of the intrinsic strength of the glass. For ion exchange performance, it can increase the stress effect of unit ion exchange of Li + + plasmas in the chemical strengthening process, but may reduce the exchange speed. However, too much Y2O3 is not conducive to obtaining transparent spinel glass-ceramics. In the present application, the mass percentage of Y2O3 in the composition of the center of the strengthened glass-ceramics or the composition of the tensile stress layer or the composition of the glass-ceramics used for preparing the strengthened glass-ceramics or the composition of the base glass is 0% to 6.00%, preferably 0% to 4.00%, and more preferably 0% to 2.00%.

[0179] ​In some embodiments of the application, the content of Y2O3 in the composition of the center of the strengthened glass ceramic or the composition of the tensile stress layer of the strengthened glass ceramic or the composition of the glass ceramic used to prepare the strengthened glass ceramic or the composition of the base glass can be 0%, 0.50%, 1.00%, 1.50%, 2.00%, 2.50%, 3.00%, 3.50%, 4.00%, 4.50%, 5.00%, 5.50%, 6.00%, 1.52%, or 0.60%, or can be a value within a range of values formed by any two of the above specific numerical values as endpoints, as long as a glass ceramic or strengthened glass ceramic with the required properties of the application can be obtained. It should be understood that in specific embodiments, any of the above ranges can be combined with any other range, as long as a glass ceramic or strengthened glass ceramic with the required properties of the application can be obtained.

[0180] In the present application, La2O3 is a network modifier component of the glass, and an appropriate amount of La2O3 can increase the refractive index of the glass, reduce the high-temperature viscosity of the glass, and help to improve the glass melting effect and eliminate its internal defects. At the same time, an appropriate amount of La2O3 can significantly improve the Young's modulus and Vickers hardness of the glass, and also has the effect of improving the chemical strengthening performance of the glass ceramic and increasing the stress effect per ion exchange of the strengthened glass ceramic. However, too much La2O3 is not conducive to obtaining transparent spinel glass ceramics. In the present application, the mass percentage of La2O3 in the composition of the center of the strengthened glass ceramic or the composition of the tensile stress layer of the strengthened glass ceramic or the composition of the glass ceramic used to prepare the strengthened glass ceramic or the composition of the base glass is 0% to 12.00%, preferably 0% to 5.00%, and more preferably 0% to 3.00%.

[0181] In some embodiments of the application, the content of Y2O3 in the composition of the center of the strengthened glass ceramic or the composition of the tensile stress layer of the strengthened glass ceramic or the composition of the glass ceramic used to prepare the strengthened glass ceramic or the composition of the base glass can be 0%, 0.50%, 1.00%, 1.50%, 2.00%, 2.50%, 3.00%, 3.50%, 4.00%, 5.00%, 6.00%, 7.00%, 8.00%, 9.00%, 10.00%, 11.00%, 12.00%, 2.17%, or 3.69%, or can be a value within a range of values formed by any two of the above specific numerical values as endpoints, as long as a glass ceramic or strengthened glass ceramic with the required properties of the application can be obtained. It should be understood that in specific embodiments, any of the above ranges can be combined with any other range, as long as a glass ceramic or strengthened glass ceramic with the required properties of the application can be obtained.

[0182] In the present application, in order to obtain the strengthened glass ceramic having excellent performance as desired in the present application, in addition to Y2O3 and La2O3, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium or scandium metal oxides, or a mixture of the foregoing metal oxides can also be added to the composition of the glass ceramic used for preparing the strengthened glass ceramic or the base material glass, as long as the glass ceramic or the strengthened glass ceramic having the desired performance in the present application can be obtained. If the foregoing metal oxides are added to the composition of the glass ceramic used for preparing the strengthened glass ceramic or the base material glass, these metal oxides should also be contained in the composition of the strengthened glass ceramic at the center or the tensile stress layer.

[0183] In the present application, on the basis of adjusting and controlling the content range of each oxide component, by adjusting and controlling the matching relationship between each oxide component, especially the mass percentage relationship between Na2O and Li2O and between Li2O and SiO2, it is beneficial to improve the intrinsic strength and chemical strengthening effect of the glass ceramic, and further to obtain the strengthened glass ceramic having excellent mechanical strength performance.

[0184] In some embodiments of the present application, in the composition of the strengthened glass ceramic at the center or the tensile stress layer or the composition of the glass ceramic used for preparing the strengthened glass ceramic or the base material glass, the mass percentage of Na2O [Na2O] and the mass percentage of Li2O [Li2O] satisfy the following relationship: [Na2O] / [Li2O] = 0.60-6.00, preferably [Na2O] / [Li2O] = 0.90-5.00, more preferably [Na2O] / [Li2O] = 1.00-3.00.

[0185] In some embodiments, in the composition of the strengthened glass ceramic at the center or the tensile stress layer or the composition of the glass ceramic used for preparing the strengthened glass ceramic or the base material glass, the ratio [Na2O] / [Li2O] of the mass percentage of Na2O [Na2O] and the mass percentage of Li2O [Li2O] can be 0.60, 0.9, 1.00, 1.50, 2.00, 2.50, 3.00, 3.50, 4.00, 4.50, 5.00, 5.50 or 6.00, or can be a value within the numerical range formed by any two of the above specific values as endpoints, as long as the glass ceramic or the strengthened glass ceramic having the desired performance in the present application can be obtained. It should be understood that in specific embodiments, any of the above ranges can be combined with any other range, as long as the glass ceramic or the strengthened glass ceramic having the desired performance in the present application can be obtained.

[0186] In some embodiments of the present application, the ratio of the mass percentage of Li2O [Li2O] to the mass percentage of SiO2 [SiO2] in the composition at the center of the strengthened glass-ceramic or the composition of the strengthened glass-ceramic or the composition of the glass-ceramic used to prepare the strengthened glass-ceramic or the composition of the base glass satisfies the following relationship: [Li2O] / [SiO2] = 0.03-0.20, preferably [Li2O] / [SiO2] = 0.04-0.15, more preferably [Li2O] / [SiO2] = 0.04-0.10.

[0187] In some embodiments, the ratio of the mass percentage of Li2O [Li2O] to the mass percentage of SiO2 [SiO2] [Li2O] / [SiO2] in the composition at the center of the strengthened glass-ceramic or the composition of the strengthened glass-ceramic or the composition of the glass-ceramic used to prepare the strengthened glass-ceramic or the composition of the base glass can be 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.10, 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17, 0.18, 0.19 or 0.20, or can be a value within a range defined by any two of the above specific values as endpoints, as long as a glass-ceramic or strengthened glass-ceramic with the desired properties of the present application is obtained. It should be understood that in specific embodiments, any of the above ranges can be combined with any other range, as long as a glass-ceramic or strengthened glass-ceramic with the desired properties of the present application is obtained.

[0188] In the present application, neither the (Zn, Mg) Al2O4 spinel solid solution nor the tetragonal ZrO2 phase contains alkali metal ions, and thus does not participate in ion exchange during chemical strengthening. Based on this, the crystal phase structure of the strengthened glass-ceramic obtained by chemical strengthening in the present application is substantially the same as that of the glass-ceramic used for chemical strengthening. That is, the crystal phase content, crystal composition, crystal size and other crystal phase structure characteristics of the strengthened glass-ceramic obtained by chemical strengthening in the present application are substantially the same as those of the glass-ceramic used for chemical strengthening in the present application. As shown in FIG. 1, in Example 1, the XRD patterns of the glass-ceramic before chemical strengthening and the strengthened glass-ceramic obtained after chemical strengthening are substantially the same. In addition, as shown in FIG. 2, in the present application, the transmittance of the glass-ceramic before and after chemical strengthening is also substantially the same, that is, in the present application, by using a glass-ceramic with high transmittance, a strengthened glass-ceramic product with the same excellent transmittance can be obtained by chemical strengthening.

[0189] It should be understood that the stress structure generated by the chemical strengthening process can improve the mechanical properties of the glass product appropriately, and therefore, in the present application, the mechanical properties such as Young's modulus and Vickers hardness of the glass-ceramic do not decrease after the glass-ceramic is treated to obtain the strengthened glass-ceramic.

[0190] In some embodiments of the present application, the average crystal size in the strengthened glass-ceramic or the glass-ceramic used to prepare the strengthened glass-ceramic is not more than 20.0 nm, preferably 1.0 nm to 10.0 nm, more preferably 4.0 nm to 9.0 nm, and more preferably 4.0 nm to 8.0 nm. The appropriate average crystal size is beneficial to the glass-ceramic having excellent optical properties and high intrinsic strength, and if the average crystal size is too high, the glass-ceramic is prone to devitrification, and the chemical strengthening effect is also affected.

[0191] In some embodiments, the average crystal size in the glass-ceramic or the strengthened glass-ceramic can be 4.0 nm, 5.0 nm, 6.0 nm, 7.0 nm, 8.0 nm, 9.0 nm, 10.0 nm, 11 nm, 12 nm, 13 nm, 14 nm, 15 nm, 16 nm, 17 nm, 18 nm, 19 nm, 20 nm, 6.8 nm, 6.4 nm, 6.5 nm, 8.1 nm, 6.1 nm, 5.1 nm, or 6.2 nm, or can be a value within a range defined by any two of the above specific values as endpoints, as long as the glass-ceramic or the strengthened glass-ceramic having the required properties of the present application can be obtained. It should be understood that in specific embodiments, any of the above ranges can be combined with any other range, as long as the glass-ceramic or the strengthened glass-ceramic having the required properties of the present application can be obtained.

[0192] In some embodiments of the present application, the total crystalline phase content in the strengthened glass-ceramics or the glass-ceramics used to prepare the strengthened glass-ceramics is in the range of 25% to 60%, preferably in the range of 30% to 55%, and more preferably in the range of 40% to 50% by mass. The higher the total crystalline phase content of the glass-ceramics or the strengthened glass-ceramics, the more beneficial it is for the glass-ceramics or the strengthened glass-ceramics to obtain high intrinsic strength. However, too high total crystalline phase content not only affects the chemical strengthening effect of the glass-ceramics, prolonging the chemical strengthening time for the glass-ceramics to obtain strengthened glass-ceramics with high stress level, but also can affect the optical performance of the glass-ceramics. In some embodiments, the total crystalline phase content in the strengthened glass-ceramics or the glass-ceramics used to prepare the strengthened glass-ceramics can be 30.00%, 31.00%, 32.00%, 33.00%, 34.00%, 35.00%, 36.00%, 37.00%, 38.00%, 39.00%, 40.00%, 41.00%, 42.00%, 43.00%, 44.00%, 45.00%, 46.00%, 47.00%, 48.00%, 49.00%, 50.00%, 55.00%, 60.00%, 48.69%, 45.11%, 49.52%, 47.85%, 54.07%, 51.56%, 45.49%, 44.77%, 52.28%, 35.52%, 48.75%, or 44.33%, or a value within a range defined by any two of the above specific values as endpoints, as long as a glass-ceramics or a strengthened glass-ceramics with the desired properties of the present application can be obtained. It should be understood that in specific embodiments, any of the above ranges can be combined with any other range, as long as a glass-ceramics or a strengthened glass-ceramics with the desired properties of the present application can be obtained.

[0193] In the present application, "main crystalline phase zinc aluminate-magnesium aluminate spinel solid solution" or other similar expressions mean that the zinc aluminate-magnesium aluminate spinel solid solution accounts for more than 50% by mass of all crystalline phases of the glass-ceramic or the strengthened glass-ceramic according to the embodiments of the present application. In some embodiments, the mass of the zinc aluminate-magnesium aluminate spinel solid solution accounts for more than 50% of all crystalline phases of the glass-ceramic or the strengthened glass-ceramic prepared from the glass-ceramic, preferably, the mass of the zinc aluminate-magnesium aluminate spinel solid solution accounts for more than 70% of all crystalline phases of the glass-ceramic or the strengthened glass-ceramic prepared from the glass-ceramic. For example, the mass fraction (or also referred to as the weight fraction, mass percentage, or weight percentage) of the zinc aluminate-magnesium aluminate spinel solid solution crystalline phase in all crystalline phases of the glass-ceramic or the strengthened glass-ceramic prepared from the glass-ceramic can be 50%, 60%, 70%, 79%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, or 90%, or can be a value within a value range formed by any two of the above specific values as end points, as long as a glass-ceramic or a strengthened glass-ceramic with the required properties of the present application can be obtained. It should be understood that in specific embodiments, any of the above ranges can be combined with any other range, as long as a glass-ceramic or a strengthened glass-ceramic with the required properties of the present application can be obtained.

[0194] In the present application, by making the glass-ceramic or the strengthened glass-ceramic meet the desired total crystalline phase content / crystallinity, appropriate average crystal size, it is beneficial to make the glass-ceramic or the strengthened glass-ceramic maintain excellent optical performance while meeting excellent mechanical strength performance and high intrinsic strength, and obtain the desired chemical strengthening effect.

[0195] In some embodiments of the present application, the strengthened glass-ceramic or the glass-ceramic for preparing the strengthened glass-ceramic is transparent in the visible light wavelength range, preferably, the transmittance of the strengthened glass-ceramic or the glass-ceramic for preparing the strengthened glass-ceramic at a wavelength of 550 nm is ≥85.00% at a thickness of 0.90 mm, preferably the transmittance is ≥87.00%. The glass-ceramic or the strengthened glass-ceramic meeting the transmittance can ensure better light transmittance, better transparency, and is suitable for use in electronic device display screens that require display effects. The "visible light wavelength range" herein refers to light with a wavelength of 360 nm-740 nm.

[0196] In some embodiments, the strengthened glass-ceramic or the glass-ceramic used to make the strengthened glass-ceramic can have a transmittance at a 550 nm wavelength of 86.00%, 87.00%, 88.00%, 88.50%, 89.00%, 89.10%, 89.20%, 89.30%, 89.40%, 89.50%, 89.60%, 89.70%, 89.80%, 89.90%, 90.00%, 90.10%, 90.20%, 90.30%, 90.40%, 90.50%, 91.00%, 92.00%, 89.73%, 89.48%, 89.87%, 89.66%, 89.15%, 89.43%, 89.65%, 89.71%, 89.14%, 89.75%, 89.90%, 89.85%, or 88.53% at a thickness of 0.90 mm, or a value within a range having any two of these specifically endpoints, as long as a glass-ceramic or strengthened glass-ceramic having the desired properties of the present application is obtained. It will be appreciated that in specific embodiments, any of the above ranges can be combined with any other range, as long as a glass-ceramic or strengthened glass-ceramic having the desired properties of the present application is obtained.

[0197] In some embodiments of the present application, the strengthened glass-ceramic has a Vickers hardness of greater than or equal to 750 kgf / mm 2 , preferably, the strengthened glass-ceramic has a Vickers hardness of greater than or equal to 790 kgf / mm 2 . A Vickers hardness of the strengthened glass-ceramic within the above range indicates that the strengthened glass-ceramic has high hardness and high intrinsic strength, thereby ensuring excellent mechanical properties.

[0198] In some embodiments, the strengthened glass-ceramic can have a Vickers hardness of 790 kgf / mm 2 , 795 kgf / mm 2 , 800 kgf / mm 2 , 805 kgf / mm 2 , 810 kgf / mm 2 , 815 kgf / mm 2 , 820 kgf / mm 2 , 825 kgf / mm 2 , 830 kgf / mm 2 , 835 kgf / mm 2 , 840 kgf / mm 2 , 845 kgf / mm 2 , 850 kgf / mm 2 , 855 kgf / mm 2 , 860 kgf / mm 2, 865 kgf / mm 2 , 870 kgf / mm 2 , 875 kgf / mm 2 , 880 kgf / mm 2 , 885 kgf / mm 2 , 890 kgf / mm 2 , 895 kgf / mm 2 , 900 kgf / mm 2 , 848 kgf / mm 2 , 879 kgf / mm 2 , 889 kgf / mm 2 , 836 kgf / mm 2 , 911 kgf / mm 2 , 897 kgf / mm 2 , 807 kgf / mm 2 , 894 kgf / mm 2 , 883 kgf / mm 2 , 873 kgf / mm 2 , 863 kgf / mm 2 , or 856 kgf / mm 2 , or can be a value within a range of values defined between any two of the above-mentioned specific values as endpoints, as long as the strengthened glass-ceramic has the desired properties. It should be understood that in specific embodiments, any of the above-mentioned ranges can be combined with any other range, as long as the strengthened glass-ceramic has the desired properties.

[0199] In some embodiments of the present application, the strengthened glass-ceramic has a fracture toughness value greater than or equal to 1.00 MPa-m 0.5 , preferably, the strengthened glass-ceramic has a fracture toughness value greater than or equal to 1.20 MPa-m 0.5 , more preferably, the strengthened glass-ceramic has a fracture toughness value greater than or equal to 1.50 MPa-m 0.5 .

[0200] In the present application, by having the strengthened glass-ceramic have a high Vickers hardness and fracture toughness, the strengthened glass-ceramic is less likely to break when subjected to a crush or impact, which is advantageous for improving the crush resistance of the strengthened glass-ceramic.

[0201] In some embodiments, the strengthened glass-ceramic can have a fracture toughness value of 1.20 MPa-m 0.5 , 1.30 MPa-m 0.5 , 1.45 MPa-m 0.5 , 1.50 MPa-m 0.5 , 1.55 MPa-m 0.51.60 MPa-m 0.5 1.65 MPa-m 0.5 1.70 MPa-m 0.5 1.75 MPa-m 0.5 1.80 MPa-m 0.5 1.85 MPa-m 0.5 1.90 MPa-m 0.5 1.95 MPa-m 0.5 2.00 MPa-m 0.5 1.64 MPa-m 0.5 1.66 MPa-m 0.5 1.71 MPa-m 0.5 1.63 MPa-m 0.5 1.74 MPa-m 0.5 1.72 MPa-m 0.5 1.59 MPa-m 0.5 1.69 MPa-m 0.5 1.57 MPa-m 0.5 1.67 MPa-m 0.5 or any value falling within a range defined by any two of the above specific numerical values as endpoints, as long as a strengthened glass-ceramic having the desired properties of the present application is obtained. It should be understood that in specific embodiments, any of the above ranges can be combined with any other range, as long as a strengthened glass-ceramic having the desired properties of the present application is obtained.

[0202] In some embodiments of the present application, the strengthened glass-ceramic has a |CT AV| of no more than 60 MPa, preferably a |CT AV| of from 4.00 MPa to 55.00 MPa, and more preferably a |CT AV| of from 4.00 MPa to 20.00 MPa, |CT AV| being the absolute value of the average tensile stress, as determined by SLP_2000.

[0203] In some embodiments, the strengthened glass ceramic can have a |CT AV| of 4.00 MPa, 5.00 MPa, 6.00 MPa, 7.00 MPa, 8.00 MPa, 9.00 MPa, 10.00 MPa, 11.00 MPa, 12.00 MPa, 13.00 MPa, 14.00 MPa, 15.00 MPa, 16.00 MPa, 17.00 MPa, 18.00 MPa, 19.00 MPa, 20.00 MPa, 30.00 MPa, 40.00 MPa, 50.00 MPa, 60.00 MPa, 6.68 MPa, 5.85 MPa, 12.45 MPa, 5.45 MPa, 7.33 MPa, 7.79 MPa, 10.91 MPa, 14.64 MPa, 9.98 MPa, 6.25 MPa, 13.15 MPa, 8.58 MPa, 6.33 MPa, 7.91 MPa, 10.75 MPa, 12.77 MPa, 13.58 MPa, 9.47 MPa, or 7.98 MPa, or a value within a range defined by any two of the above specifically named values as endpoints, as long as a strengthened glass ceramic having the desired properties of the application is obtained. It is understood that in specific embodiments, any of the above ranges can be combined with any other range, as long as a strengthened glass ceramic having the desired properties of the application is obtained.

[0204] In some embodiments of the application, the strengthened glass ceramic has a |CT CV| of no more than 75 MPa, preferably a |CT CV| of 5.00 MPa to 70.00 MPa, preferably a |CT CV| of 6.00 MPa to 25.00 MPa, |CT CV| being the absolute value of the maximum tensile stress, as determined by SLP_2000.

[0205] In some embodiments, the |CT_CV| of the strengthened glass ceramic is 5.00 MPa, 6.00 MPa, 7.00 MPa, 8.00 MPa, 9.00 MPa, 10.00 MPa, 11.00 MPa, 12.00 MPa, 13.00 MPa, 14.00 MPa, 15.00 MPa, 16.00 MPa, 17.00 MPa, 18.00 MPa, 19.00 MPa, 20.00 MPa, 21.00 MPa, 22.00 MPa, 23.00 MPa, 24.00 MPa, 25.00 MPa, 35.00 MPa, 45.00 MPa, 55.00 MPa, 65.00 MPa, 75.00 MPa, 7.87 MPa, 6.96 MPa, 15.32 MPa, 6.84 MPa, 8.12 MPa, 9.01 MPa, 11.79 MPa, 17.92 MPa, 11.70 MPa, 7.76 MPa, 15.90 MPa, 9.45 MPa, 8.68 MPa, 9.13 MPa, 12.07 MPa, 14.12 MPa, 15.74 MPa, 10.75 MPa, or 9.02 MPa, or a value within a range defined by any two of the above specific values as endpoints, as long as a strengthened glass ceramic with desired properties of the present application can be obtained. It should be understood that in specific embodiments, any of the above ranges can be combined with any other range, as long as a strengthened glass ceramic with desired properties of the present application can be obtained.

[0206] In the present application, by making the strengthened glass ceramic satisfy a suitable stress structure, it is beneficial to exert the improvement effect of the stress structure on the mechanical strength properties, especially the excellent compression resistance properties to be achieved in the present application.

[0207] In some embodiments of the present application, a 10 mm diameter round head metal pressure rod is used to apply a vertical downward load step by step at a rate of 10 mm / min to press the center of the main surface of the strengthened glass ceramic, and the single rod static pressure strength that the strengthened glass ceramic can withstand is tested. The single rod static pressure strength that the strengthened glass ceramic can withstand is greater than 800 N. In the present application, the single rod static pressure strength is used to represent the compression resistance of the strengthened glass ceramic. The greater the single rod static pressure strength that the strengthened glass ceramic can withstand, the better the compression resistance.

[0208] After the foregoing introduces the composition, crystal phase structure, and stress structure of the strengthened glass ceramic, the preparation method of the strengthened glass ceramic is specifically introduced below.

[0209] In the present application, the preparation process of the strengthened glass ceramic mainly includes: the preparation process of the glass ceramic and the chemical strengthening process, and the preparation process of the glass ceramic mainly includes: the preparation process of the base glass and the heat treatment process of the base glass.

[0210] In the present application, the base glass can be prepared by using the forming method in the prior art, and the present application does not have any limitation in this regard. For example, the forming method of the base glass can include but is not limited to the float method, the overflow method, the calendering process or the casting process. Illustratively, the components are mixed according to the formula, and after the melt forming, the cooling and annealing treatment are performed, and the base glass can be obtained.

[0211] Illustratively, the raw materials (industrial conventional raw materials) are prepared according to the formula, a refining agent is added, and then the raw material mixture is mixed for a period of time to obtain a uniformly mixed raw material mixture. The raw material mixture is placed in a platinum crucible, heated to 1450°C to 1800°C, preferably the melting temperature is 1550°C to 1680°C, and preferably the temperature is maintained for 3 to 12 hours, and then poured into a forming mold for cooling and forming, preferably cooled to 800°C to 1000°C, and then placed in an annealing furnace for annealing treatment, preferably the annealing temperature is 500°C to 700°C, and the annealing time is preferably 4 to 48 hours; and then the furnace is cooled to room temperature, and the base glass can be obtained. The person skilled in the art can select the type and amount of the refining agent according to the needs, and it does not require creative labor. Further, the refining agent can include but is not limited to one or more of sodium chloride, tin oxide, antimony oxide or arsenic oxide, and the refining agent can be added in an amount of 0wt% to 1wt% of the total amount of the raw material.

[0212] In some embodiments of the present application, the heat treatment process of the base glass can include nucleation treatment and / or crystallization treatment, and preferably both nucleation treatment and crystallization treatment are used. In some embodiments, the crystallization treatment includes one-step crystallization treatment or multi-step crystallization treatment.

[0213] In some embodiments of the present application, in order to obtain the desired physical and chemical properties of the glass ceramic, the heat treatment of the base glass can be performed in one step or in two or more steps. If the heat treatment is performed in one step, it means that the nucleation treatment (i.e., nucleation treatment) is not performed separately, and the nucleation and target crystal growth are directly performed in one temperature rising process, which can be understood as directly performing the crystallization treatment. If the heat treatment is performed in two steps, it means that the nucleation treatment (i.e., nucleation treatment) is performed first, and then the crystal growth treatment (i.e., crystallization treatment) is performed.

[0214] In the present application, in order to make the glass-ceramic precipitate the desired crystal phase and obtain the desired physical and chemical properties, further, the temperature of the nucleation treatment can be 600-850°C, the time of the nucleation treatment can be 0-72h, preferably 0-10h; the temperature of the crystallization treatment can be 700-1000°C, the time of the crystallization treatment can be 0.10-24h, preferably 0.1-6h. When performing the heat treatment, the temperature rising rate is preferably controlled to be 5-15°C / min, more preferably the temperature rising rate is 10°C / min. The temperature of the nucleation treatment refers to the temperature at which the crystal nucleus can form. The temperature of the crystallization treatment refers to the temperature at which the target crystal can grow controllably.

[0215] After the heat treatment, the person skilled in the art can also perform other conventional steps to obtain the glass-ceramic sample / patch that meets the required specifications or requirements, for example, the sample / patch can be subjected to shaping treatment, cutting treatment (such as cutting using a multi-wire cutting machine), CNC processing (computer numerical control), thinning treatment or polishing treatment, etc.

[0216] In some embodiments of the present application, the strengthened glass-ceramic that meets the desired performance can be prepared by performing specific chemical strengthening treatment on the aforementioned glass-ceramic.

[0217] In the present application, the chemical strengthening treatment, i.e. the ion exchange method, is performed by immersing the glass-ceramic in a molten salt bath, so that the alkali metal ions with a smaller ionic radius in the glass-ceramic are exchanged with the alkali metal ions with a larger ionic radius in the molten salt bath, thereby forming a compressive stress layer on the surface of the glass-ceramic to obtain a strengthened glass-ceramic with better mechanical properties.

[0218] In some embodiments of the present application, the chemical strengthening treatment can be performed by a single-step strengthening method or a multi-step strengthening method. The molten salt bath used in the chemical strengthening treatment is a molten salt bath containing sodium salt and / or potassium salt. Preferably, in the present application, the chemical strengthening is performed by a single-step strengthening method, and the molten salt bath used in the strengthening process is a salt bath containing pure potassium salt, or a mixed salt bath in which the mass percentage of potassium salt is not less than 90%. The temperature of the molten salt bath is preferably 380-600°C, more preferably 400-500°C. In some embodiments of the present application, a certain amount (e.g. 0-0.5wt%) of lithium salt can be added to the salt bath. In some embodiments of the present application, the time of the chemical strengthening treatment is preferably 0.1-48h, preferably 0.1-24h. The sodium salt can be selected from at least one of sodium nitrate, sodium sulfate and sodium carbonate, preferably sodium nitrate; the potassium salt can be selected from at least one of potassium nitrate, potassium sulfate and potassium carbonate, preferably potassium nitrate; and the lithium salt can be selected from at least one of lithium nitrate, lithium sulfate and lithium carbonate, preferably lithium nitrate.

[0219] In some embodiments of the present application, the strengthened glass ceramic can be prepared by subjecting a glass ceramic having a fracture toughness of no less than 1.40 MPa·m 0.5 to a chemical strengthening treatment. Preferably, the strengthened glass ceramic can be prepared by subjecting a glass ceramic having a fracture toughness of no less than 1.40 MPa·m 0.5 to a single-step chemical strengthening treatment. More preferably, a glass ceramic having a fracture toughness of no less than 1.40 MPa·m 0.5 can be subjected to a single-step chemical strengthening treatment in a molten salt bath comprising potassium salt and having a mass percentage of potassium salt of no less than 90% to obtain the strengthened glass ceramic having a specific surface composition and excellent extrusion resistance.

[0220] The glass ceramic or strengthened glass ceramic having excellent performance (especially excellent extrusion resistance) provided by the present application can be used in electronic devices, including but not limited to mobile phones, tablet computers, handheld game consoles, portable digital devices (such as digital cameras), vehicle-mounted control panels, electronic whiteboard glasses, smart home, smart wear (such as smart wristbands, smart watches, smart glasses), and can also be used in vehicles, aircraft or vessels, and can also be used in any desired glass ceramic or strengthened glass ceramic glassware. For example, it can be used in the display screen, cover glass, touch screen, glass inner screen or inner frame of an electronic device; for example, it can be used in the windshield of a vehicle, aircraft or vessel, such as the front windshield or side windshield. For example, it can be used in worktops, other surfaces, appliance doors, floor tiles, wall panels or storage containers, etc. Other surfaces can include but are not limited to exterior wall surfaces, stair tread surfaces, column facings or counter surfaces, etc., and storage containers can include but are not limited to cups, plates, medicine bottles or beverage bottles, etc.

[0221] For example, the glass ceramic or strengthened glass ceramic having excellent performance provided by the present application can be used to manufacture glassware. The glassware referred to herein can be regular or irregular, and those skilled in the art can manufacture it according to the needs.

[0222] Exemplarily, the glass-ceramics or strengthened glass-ceramics provided by the present application with excellent performance (especially excellent extrusion resistance) can be used to manufacture cover glasses, which can be display screen cover plates, back covers or camera protection cover plates of electronic devices. Exemplarily, the glass-ceramics or strengthened glass-ceramics provided by the present application with excellent performance can be used in electronic devices. Referring to FIGS. 7, 8, 9 and 10, in some embodiments of the present application, an electronic device, which can be a mobile phone (as shown in FIG. 7), a tablet computer, a smart wearable device (as shown in FIG. 10) or the like, comprises a housing 1 assembled on the outer side of the electronic device, the housing 1 comprises a display screen cover plate 11 assembled on the front side and a back cover 12 assembled on the back side, the display screen cover plate 11 covers the display module 4, wherein the display screen cover plate 11 and / or the back cover 12 are made of the aforementioned glass-ceramics or strengthened glass-ceramics. In the present application, the display screen cover plate 11 and the back cover 12 can be made of the aforementioned glass-ceramics or strengthened glass-ceramics entirely or partially.

[0223] In some embodiments of the present application, as shown in FIG. 8, the electronic device further comprises a camera assembly 2 located inside the housing 1, the housing 1 can comprise a camera protection cover plate 13 covering the camera assembly 2 for protecting the camera assembly 2, the camera protection cover plate 13 is made of the aforementioned glass-ceramics or strengthened glass-ceramics. In the present application, the camera protection cover plate 13 can be made of the aforementioned glass-ceramics or strengthened glass-ceramics partially or entirely. In the present application, the camera protection cover plate 13 can be located on the front side of the electronic device or on the back side of the electronic device according to the location of the camera assembly 2. In some embodiments of the present application, the camera protection cover plate 13 can be in a separate structure from the display screen cover plate 11 or the back cover 12. In another embodiments of the present application, the camera protection cover plate 13 can be in an integrated structure with the display screen cover plate 11 or the back cover 12.

[0224] In some embodiments of the present application, as shown in FIG. 9, the electronic device further comprises a middle frame 3 located between the display module 4 and the housing 1, the middle frame 3 can comprise the aforementioned glass-ceramics or strengthened glass-ceramics.

[0225] In the embodiments of the present application, the display screen cover plate, the back cover, the camera protection cover plate, and the middle frame in the electronic device can be any one, any two, any three, or all of the four, which adopt the aforementioned glass ceramic or strengthened glass ceramic.

[0226] In some embodiments of the present application, the display screen cover plate, the back cover, the camera protection cover plate, or the middle frame in the electronic device can be 2D, 2.5D, 3D, or special-shaped. In some embodiments of the present application, the display screen cover plate, the back cover, the camera protection cover plate, or the middle frame in the electronic device can be of equal thickness or unequal thickness.

[0227] The technical solutions of the present application are further described in detail below in combination with embodiments. The embodiments of the present application described in detail below are exemplary and are only used to explain the present application, and cannot be understood as a limitation of the present application.

[0228] Embodiment 1

[0229] A strengthened glass ceramic is prepared as follows:

[0230] (1) Preparation of base material glass:

[0231] Each raw material (industrial conventional raw material) is configured according to the proportion of each component in Table 1, the total mass of the configured raw materials is 1000g, 5g of clarifying agent sodium chloride (NaCl) is added to the configured raw materials, and then a V-type mixer is used for mixing for 30 minutes to obtain a raw material mixture with uniform mixing.

[0232] The raw material mixture is transferred to a platinum crucible, then melted in the platinum crucible at 1650℃ for 5 hours, and then poured into a forming mold for cooling, cooled to 900℃, and then placed in a 600℃ annealing furnace for annealing for 24 hours, and then cooled to room temperature with the furnace, to obtain a base material glass brick.

[0233] (2) Preparation of glass ceramic: according to the heat treatment process in Table 2, the base material glass brick is placed in an annealing furnace, heated from room temperature to 750℃ at a rate of 10℃ / min for nucleation treatment, kept at this temperature for 240min, then heated to 765℃ at a rate of 10℃ / min for crystallization treatment, kept at this temperature for 120min, and then cooled to room temperature at a rate of 1℃ / min. The glass ceramic sample brick is obtained. The composition of the prepared glass ceramic is the same as that of the base material glass, and is shown in Table 1.

[0234] The obtained glass-ceramic sample bricks are subjected to cold processing of cutting, CNC processing (the CNC instrument used in the present application is RCG500S), and polishing in sequence, and glass-ceramic samples / slices meeting the required specifications and requirements can be prepared. In Examples 1-20 and Comparative Examples 1-15 of the present application, the glass-ceramic sample bricks are subjected to the aforementioned cold processing to prepare glass-ceramic samples / slices with thicknesses of 0.70 mm, 0.90 mm, 0.95 mm, or 1.05 mm. Specifically, circular glass-ceramic polished slice samples / slices with a diameter of 46 mm and thicknesses of 0.70 mm, 0.90 mm, 0.95 mm, or 1.05 mm are prepared.

[0235] Test conditions for the glass-ceramic samples / slices obtained in Example 1:

[0236] The crystalline phase composition, average crystal size, total content of crystalline phases, transmittance (at a wavelength of 550 nm), density, Vickers hardness, and fracture toughness of the glass-ceramics are tested, and the results are shown in Table 2.

[0237] (3) Preparation of strengthened glass-ceramics: The obtained glass-ceramic samples / slices are placed in a strengthening furnace cavity and preheated for 5 min according to the chemical strengthening process in Table 3. After preheating, the glass-ceramic samples / slices are quickly placed in a 430℃ molten salt bath for chemical strengthening treatment. The composition of the molten salt is 100wt% KNO3. The chemical strengthening treatment time is 1 h. After that, the glass-ceramic samples / slices are taken out and slowly cooled to room temperature on the furnace body of the strengthening furnace. The salt on the surface of the glass-ceramic is washed off with clean water. After drying treatment of the glass-ceramic samples / slices, the strengthened glass-ceramics are obtained.

[0238] Test conditions for the strengthened glass-ceramic samples / slices obtained in Example 1:

[0239] I. The |CT_CV| and |CT_AV| of the strengthened glass-ceramics are measured on an SLP-2000 stress meter (the wavelength of the light source used is 518 nm, SOC = 25.5 (nm / cm) / MPa, the refractive index is set to 1.60, and the exposure time is 300 μsec). The results are shown in Table 3.

[0240] II. The surface Na2O mass percentage and surface K2O mass percentage of the strengthened glass-ceramics are measured by XRF. The results are shown in Table 3.

[0241] III. The DOL_K of the strengthened glass-ceramics is measured by micro-area composition analysis using the electron beam to act on the sample to generate characteristic X-rays on Shimadzu electron probe EPMA-1720HT. The results are shown in Table 3.

[0242] IV. The Vickers hardness and fracture toughness of the strengthened glass-ceramics and the single-rod static pressure strength that the strengthened glass-ceramics can withstand are tested, and the results are shown in Table 3.

[0243] Examples 2-19

[0244] Each of the examples is performed with reference to Example 1, except that the raw material composition, different process parameters, and the corresponding test results of each example are shown in Tables 1-3.

[0245] The XRD pattern comparison chart of the glass-ceramics and the strengthened glass-ceramics of Example 1 is shown in FIG. 1. From the chart, it can be seen that ① the main crystal phase of the glass-ceramics and the strengthened glass-ceramics is a zinc-aluminum spinel-magnesium-aluminum spinel solid solution (Zn, Mg) Al2O4, and the secondary crystal phase is ZrO2; ② the XRD patterns of the glass-ceramics and the strengthened glass-ceramics are basically coincident, indicating that the crystal phase structure is basically unchanged before and after chemical strengthening.

[0246] The transmittance curve comparison chart of the glass-ceramics and the strengthened glass-ceramics of Example 1 is shown in FIG. 2. From the chart, it can be seen that the glass-ceramics and the strengthened glass-ceramics prepared therefrom are both transparent in the visible light range, both have high transmittance, and the transmittance is basically unchanged before and after chemical strengthening.

[0247] Comparative Examples 1-15

[0248] Each of the comparative examples is performed with reference to Example 1, except that the raw material composition, different process parameters, and the corresponding test results of each comparative example are shown in Tables 1-3.

[0249] Table 1

[0250] Note: In Table 1, the oxide content of “0” means that the component is not actively or intentionally added to the glass composition during the initial batching process, but the component can exist as an impurity.

[0251] Table 2

[0252] Note: In Table 2, “ / ” means that the operation is not performed.

[0253] Table 3

[0254] Note: 1. In Table 3, the surface K2O concentration refers to the mass percentage of K2O on the surface of the strengthened glass-ceramics, and the surface Na2O concentration refers to the mass percentage of Na2O on the surface of the strengthened glass-ceramics.

[0255] 2. In Table 3, the data in the column of "Surface K2O Concentration" or the column of "Surface Na2O Concentration" is recorded as "0.000", which means that the content of K element or Na element contained in the strengthened glass-ceramics of the tested scheme is lower than 0.0013%, i.e., lower than the testing precision (0.0013%) of the XRF instrument used in the present application. Since the content is lower than the testing precision of the XRF instrument, the instrument will not display the element and its content, and therefore, "0.000" is used in the present application to record it.

[0256] 3. In Table 3, the column of "Salt Bath Composition" of each example or comparative example, if the expressions of "first step strengthening" and "second step strengthening" are not explicitly recorded, it means that the example or comparative example uses single-step strengthening, i.e., only one step of chemical strengthening treatment is performed.

[0257] 4. In Table 3, the column of "Salt Bath Composition" explicitly records "first step strengthening" and "second step strengthening", which means that the comparative example is subjected to two-step chemical strengthening treatment, and after each step of strengthening treatment, the tests of |CT-CV| and |CT-AV| are performed, and after the second step of strengthening treatment, the surface K2O concentration, the surface Na2O concentration, DOL_K, Vickers hardness and fracture toughness of the obtained strengthened glass-ceramics are tested, and the single-rod static pressure strength that the strengthened glass-ceramics can withstand is also tested.

[0258] From the examples and comparative examples in Tables 1-3 above, it can be seen that by using the glass-ceramics satisfying the specific composition and specific crystal phase structure and having a thickness greater than 0.70 mm, the examples of the present application are subjected to chemical strengthening, and the surface composition of the obtained strengthened glass-ceramics satisfies specific requirements, especially the surface Na2O mass percentage (i.e., the surface Na2O concentration in Table 3) and the surface K2O mass percentage (i.e., the surface K2O concentration in Table 3) of the strengthened glass-ceramics and the diffusion depth of K element (i.e., DOL_K in Table 3) from the main surface of the strengthened glass-ceramics simultaneously satisfy specific requirements, which significantly improves the compression resistance of the strengthened glass-ceramics, and the strengthened glass-ceramics obtains excellent extrusion resistance and can withstand a single-rod static pressure strength greater than 800 N. + (K element) diffusion depth (i.e., DOL_K in Table 3) simultaneously satisfy specific requirements, which significantly improves the compression resistance of the strengthened glass-ceramics, and the strengthened glass-ceramics obtains excellent extrusion resistance and can withstand a single-rod static pressure strength greater than 800 N.

[0259] In the schemes of Comparative Examples 1-15, the composition of the glass-ceramics used for preparing the strengthened glass-ceramics, the thickness of the glass-ceramics or the surface composition of the obtained strengthened glass-ceramics does not satisfy the specific requirements of the present application, which finally leads to that the extrusion resistance of the obtained strengthened glass-ceramics is obviously not as good as that of the examples satisfying the requirements of the schemes of the present application.

[0260] Some comparative examples are analyzed as follows:

[0261] The base glass composition of Comparative Example 1 does not contain Li20, and does not meet the composition requirements of the present application. The Vickers hardness of the glass-ceramic prepared after heat treatment is 650 kgf / mm 2 , and the fracture toughness value is 1.32 MPa-m 0.5 . After chemical strengthening of the glass-ceramic, the surface K20 concentration of the strengthened glass-ceramic is 6.33%, and the surface Na20 concentration is 1.450%, and the DOL_K is 16.80 μm, which does not meet the surface composition requirements of the strengthened glass-ceramic of the present application. Finally, the Vickers hardness of the strengthened glass-ceramic is tested to be 774 kgf / mm 2 , and the fracture toughness is 1.53 MPa-m 0.5 , and the single rod static pressure strength that the strengthened glass-ceramic can withstand is only 599 N, which is significantly lower than the embodiment scheme of the present application.

[0262] The base glass composition of Comparative Example 2 contains 0.87% of Na20, which is too low, and does not meet the composition requirements of the present application. The Vickers hardness of the glass-ceramic prepared after heat treatment is 721 kgf / mm 2 , and the fracture toughness value is 1.47 MPa-m 1 / 2 . After chemical strengthening of the glass-ceramic, the surface K20 concentration of the strengthened glass-ceramic is 1.58%, the surface Na20 concentration is 0.000%, and the DOL_K is 4.00 μm, which does not meet the surface composition requirements of the strengthened glass-ceramic of the present application. Finally, the Vickers hardness of the strengthened glass-ceramic is tested to be 759 kgf / mm 2 , and the fracture toughness is 1.53 MPa-m 0.5 , and the single rod static pressure strength that the strengthened glass-ceramic can withstand is only 558 N, which is also significantly lower than the embodiment scheme of the present application.

[0263] The base glass composition of Comparative Example 3 contains 0.62% of Li20, which is too low, and does not meet the composition requirements of the present application. The Vickers hardness of the glass-ceramic prepared after heat treatment is 657 kgf / mm 2 , and the fracture toughness value is 1.36 MPa-m 0.5 . After chemical strengthening of the glass-ceramic, the surface K20 concentration of the strengthened glass-ceramic is 3.92%, the surface Na20 concentration is 0.000%, and the DOL_K is 9.40 μm. Finally, the Vickers hardness of the strengthened glass-ceramic is tested to be 766 kgf / mm 2 , and the fracture toughness is 1.53 MPa-m 0.5 , and the single rod static pressure strength that the strengthened glass-ceramic can withstand is only 661 N, which is also significantly lower than the embodiment scheme of the present application.

[0264] The Li2O concentration in the base glass composition of Comparative Example 4 is 0.79%, which is too low to meet the requirements of the present application. The Vickers hardness of the glass-ceramic prepared after heat treatment is 670 kgf / mm 2 , and the fracture toughness value is 1.38 MPa.m 0.5 . After chemical strengthening of the glass-ceramic, the surface K2O concentration in the strengthened glass-ceramic is 5.12%, and the surface Na2O concentration is 2.350%, which do not meet the requirements of the present application for the surface composition of the strengthened glass-ceramic; the DOL_K is 9.30 μm. Finally, the Vickers hardness of the strengthened glass-ceramic is tested to be 774 kgf / mm 2 , and the fracture toughness is 1.54 MPa.m 0.5 . The single-rod static pressure strength that the strengthened glass-ceramic can withstand is only 711 N, which is also significantly lower than the embodiment of the present application.

[0265] Comparative Examples 5 to 11 are obtained by using the glass-ceramic of Example 1 under different strengthening conditions, but the surface composition of the strengthened glass-ceramics prepared in Comparative Examples 5 to 11, especially the surface Na2O concentration, the surface K2O concentration, and the K + (K element) diffusion depth DOL_K, cannot all meet the requirements of the present application for the strengthened glass-ceramic. Finally, the single-rod static pressure strength that the strengthened glass-ceramics prepared in Comparative Examples 5 to 11 can withstand is also all lower than 800 N.

[0266] Comparative Example 12 is obtained by using the glass-ceramic of Example 11 under different strengthening conditions, and the surface Na2O concentration, the surface K2O concentration, and the K + (K element) diffusion depth DOL_K of the strengthened glass-ceramic prepared in Comparative Example 12 also cannot all meet the requirements of the present application for the strengthened glass-ceramic. Finally, the single-rod static pressure strength that the strengthened glass-ceramic prepared in Comparative Example 12 can withstand is 790 N, which is lower than 800 N.

[0267] The glass-ceramics of Comparative Examples 13 to 15 have the same composition as the glass-ceramic of Example 1, but have different thicknesses from the glass-ceramic of Example 1. Although the surface composition of the strengthened glass-ceramics prepared in Comparative Examples 13 and 15 can meet the requirements of the present application for the strengthened glass-ceramic, the single-rod static pressure strength that the strengthened glass-ceramics prepared in Comparative Examples 13 to 15 can withstand is also all lower than 800 N, which shows that the thickness has a positive effect on improving the compression resistance of the strengthened glass-ceramic.

[0268] The above merely provides specific examples of the present application, and is not intended to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall fall within the scope of the protection of the present application. Industrial applicability

[0269] The present application uses zinc-aluminum spinel-magnesium-aluminum spinel solid solution as the main crystal phase of the glass ceramic, so that the glass ceramic has high intrinsic strength. The glass ceramic with a thickness greater than 0.7 mm and containing specific contents of Li ions and Na ions is chemically strengthened, and the surface composition of the prepared strengthened glass ceramic meets specific requirements, which significantly improves the compressive resistance of the strengthened glass ceramic, and the strengthened glass ceramic has excellent extrusion resistance. The strengthened glass ceramic is applied to electronic devices, so that the electronic devices can meet the application environment with high requirements for compressive resistance, such as better matching the application requirements in water environment (such as deep sea environment), and can be applied to deep water environment.

Claims

1. A strengthened glass-ceramic, characterized in that, The thickness t of the strengthened glass ceramic is greater than 0.7 mm, preferably, the thickness t is not less than 0.8 mm, more preferably, the thickness t is not less than 0.9 mm; The strengthened glass ceramic comprises a main crystal phase of a zinc aluminate-magnesium aluminate spinel solid solution and a secondary crystal phase of zirconia; the strengthened glass ceramic has a compressive stress layer on the surface and a tensile stress in the interior; The strengthened glass ceramic comprises Li2O and Na2O at the center or in the composition of the tensile stress layer, and the mass percentage of the Li2O is greater than 1.00%, preferably, the mass percentage of the Li2O is greater than 1.30%, more preferably, the mass percentage of the Li2O is greater than or equal to 1.50%, the mass percentage of the Na2O is greater than 1.00%, preferably, the mass percentage of the Na2O is greater than 2.00%, more preferably, the mass percentage of the Na2O is greater than 2.70%, in terms of mass percentage of oxides; The surface K2O mass percentage of the strengthened glass ceramic is 2.00% to 7.50%, preferably, the surface K2O mass percentage of the strengthened glass ceramic is 2.50% to 6.50%, more preferably, the surface K2O mass percentage of the strengthened glass ceramic is 3.00% to 6.00%, in terms of mass percentage of oxides; The surface Na2O mass percentage of the strengthened glass ceramic is less than or equal to 0.010%, preferably, the surface Na2O mass percentage of the strengthened glass ceramic is less than or equal to 0.005%, more preferably, the surface Na2O mass percentage of the strengthened glass ceramic is less than or equal to 0.002%, in terms of mass percentage of oxides; The strengthened glass-ceramic satisfies: 5.00 pm < DOL_K < 20.00 pm, preferably 5.50 pm < DOL_K < 18.00 pm, more preferably 6.00 pm < DOL_K < 16.00 pm, wherein DOL_K is the K + diffusion depth.

2. The strengthened glass ceramic of claim 1, wherein, The strengthened glass ceramic satisfies: along a thickness direction of the strengthened glass ceramic, a concentration of K + decreases nonlinearly from a main surface of the strengthened glass ceramic to a center of the strengthened glass ceramic.

3. The strengthened glass ceramic of any one of claims 1-2, wherein, The strengthened glass ceramic comprises Al2O3 with a mass percentage greater than or equal to 30.00% at the center or in the composition of the tensile stress layer; and / or, the strengthened glass ceramic comprises ZrO2 with a mass percentage greater than or equal to 3.00% at the center or in the composition of the tensile stress layer, in terms of mass percentage of oxides.

4. The strengthened glass ceramic of any one of claims 1-3, wherein, The thickness t of the strengthened glass ceramic is 0.85 mm to 2.00 mm, preferably, the thickness t is 0.90 mm to 1.50 mm; and / or, The strengthened glass ceramic is 2D, 2.5D, 3D or special-shaped; and / or, The strengthened glass ceramic is equal-thickness or unequal-thickness.

5. The strengthened glass ceramic of any one of claims 1-4, wherein, The composition of the strengthened glass ceramic at the center or in the tensile stress layer comprises, in terms of mass percentage of oxides: SiO2: 25.00% to 55.00%, Al2O3: 30.00% to 55.00%, ZrO2: 3.00% to 8.00%, MgO: 2.00% to 5.00%, ZnO: 5.00% to 15.00%, Na2O: 1.00% to 10.00%, K2O: 0% to 5.00%, Li2O: 1.00% to 6.00%, CaO: 0% to 6.00%, B2O3: 0% to 10.00%, BaO: 0% to 10.00%, Y2O3: 0% to 6.00%, La2O3: 0% to 12.00%.

6. The strengthened glass ceramic of any one of claims 1-5, wherein, The composition at the center or the tensile stress layer of the strengthened glass-ceramic comprises, in mass percent of oxides: SiO2 is 30.00% to 42.00%, preferably, SiO2 is 35.00% to 40.00%; and / or, Al2O3 is 32.00% to 42.00%, preferably, Al2O3 is 34.00% to 42.00%; and / or, ZrO2 is 4.00% to 7.00%, preferably, ZrO2 is 5.00% to 6.00%; and / or, MgO is 2.50% to 4.00%, preferably, MgO is 2.50% to 3.50%; and / or, ZnO is 9.00% to 13.00%, preferably, ZnO is 9.00% to 11.00%; and / or, Na2O is 1.00% to 8.00%, preferably, Na2O is 2.00% to 6.00%; and / or, K2O is 0% to 3.00%, preferably, K2O is 0% to 1.00%; and / or, Li2O is 1.00% to 4.00%, preferably, Li2O is 2.00% to 3.00%; and / or, CaO is 0% to 3.00%, preferably, CaO is 0% to 1.50%; and / or, B2O3 is 0% to 8.00%, preferably, B2O3 is 0% to 4.00%; and / or, BaO is 0% to 7.00%, preferably, BaO is 0% to 4.00%; and / or, Y2O3 is 0% to 4.00%, preferably, Y2O3 is 0% to 2.00%; and / or, La2O3 is 0% to 5.00%, preferably, La2O3 is 0% to 3.00%.

7. The strengthened glass ceramic of any one of claims 1-6, wherein, In the composition at the center or the tensile stress layer of the strengthened glass-ceramic, the mass percent of Na2O [Na2O] and the mass percent of Li2O [Li2O] satisfy the following relationship: [Na2O] / [Li2O] = 0.60 to 6.00, preferably 0.90 to 5.00, more preferably 1.00 to 3.00; and / or In the composition at the center or the tensile stress layer of the strengthened glass-ceramic, the mass percent of Li2O [Li2O] and the mass percent of SiO2 [SiO2] satisfy the following relationship: [Li2O] / [SiO2] = 0.03 to 0.20, preferably 0.04 to 0.15, more preferably 0.04 to 0.

10.

8. The strengthened glass ceramic of any one of claims 1-7, wherein, The average crystal size in the strengthened glass ceramic is not more than 20 nm, preferably 1.0 nm to 10.0 nm, more preferably 4.0 nm to 9.0 nm, more preferably 4.0 nm to 8.0 nm; and / or The total content of the crystal phase in the strengthened glass ceramic is 25% to 60%, preferably 30% to 55%, more preferably 40% to 50% by mass percentage.

9. The strengthened glass ceramic of any one of claims 1-8, wherein, The strengthened glass ceramic is transparent in the visible light wavelength range, preferably the transmittance of the strengthened glass ceramic at a wavelength of 550 nm is ≥ 85.00%, preferably ≥ 87.00% at a thickness of 0.90 mm.

10. The strengthened glass ceramic of any one of claims 1 to 9, wherein, the strengthened glass-ceramic has a Vickers hardness greater than or equal to 750 kgf / mm 2 , preferably, the strengthened glass-ceramic has a Vickers hardness greater than or equal to 790 kgf / mm 2 ; and / or, the strengthened glass-ceramic has a fracture toughness value of 1.00 MPa.m or greater 0.5 , preferably, the strengthened glass-ceramic has a fracture toughness value of 1.20 MPa.m or greater 0.5 , more preferably, the strengthened glass-ceramic has a fracture toughness value of 1.50 MPa.m or greater 0.5 ; and / or, The strengthened glass ceramic has a |CT_AV| of not more than 60 MPa, preferably a |CT_AV| of 4.00 MPa to 55.00 MPa, preferably a |CT_AV| of 4.00 MPa to 20.00 MPa, |CT_AV| being the absolute value of the average tensile stress; and / or, The strengthened glass ceramic has a |CT_CV| of not more than 75 MPa, preferably a |CT_CV| of 5.00 MPa to 70.00 MPa, preferably a |CT_CV| of 6.00 MPa to 25.00 MPa, |CT_CV| being the absolute value of the maximum tensile stress.

11. The strengthened glass ceramic of any one of claims 1 to 10, wherein, The surface K2O mass percentage of the strengthened glass ceramic is 3.91%, 4.16%, 3.96%, 4.12%, 4.53%, 3.24%, 4.55%, 4.51%, 4.68%, 5.75%, 3.85%, 4.48%, 5.69%, 5.45%, 5.57% or 5.54%; and / or, The DOL_K of the strengthened glass ceramic is 7.70 µm, 9.60 µm, 10.30 µm, 8.40 µm, 10.40 µm, 8.60 µm, 14.10 µm, 12.50 µm, 6.20 µm, 9.80 µm, 12.80 µm, 9.10 µm, 8.30 µm, 8.80 µm, 11.40 µm, 10.60 µm, 11.80 µm or 11.70 µm.

12. The strengthened glass ceramic of any one of claims 1-11, wherein, The composition at the center or the tensile stress layer of the strengthened glass ceramic comprises, by mass percentage of oxide: The mass percentage of SiO2 is 37.08%, 36.87%, 33.23%, 37.43%, 37.40%, 38.33%, 36.05%, 35.67%, 32.39%, 37.50%, 35.64%, 37.32% or 36.31%; and / or, The mass percentage of Al2O3 is 35.83%, 36.98%, 36.27%, 37.52%, 36.60%, 37.07%, 34.84%, 34.55%, 35.88%, 38.63%, 36.23% or 35.10%; and / or, The mass percentage of Al2O3 is 35.83%, 36.98%, 36.27%, 37.52%, 36.60%, 37.07%, 34.84%, 34.55%, 35.88%, 38.63%, 36.23% or 35.10%; and / or, the mass percent of Zr02 is 5.69%, 5.65%, 5.61%, 5.74%, 5.81%, 5.89%, 5.54%, 5.48%, 5.76%, 5.72%, 5.99%, or 5.58%; and / or, the mass percent of MgO is 3.00%, 2.98%, 3.04%, 3.03%, 3.06%, 3.10%, 2.92%, 2.89%, 3.01%, 3.27%, or 2.94%; and / or, the mass percent of ZnO is 10.77%, 10.71%, 10.55%, 10.87%, 11.01%, 11.15%, 10.46%, 10.37%, 12.50%, 10.82%, 11.33%, or 10.54%; and / or, the mass percent of Na20 is 2.86%, 2.85%, 2.89%, 3.00%, 1.69%, 2.79%, 2.76%, 3.31%, 4.61%, 3.01%, or 8.00%; and / or, preferably free of K20; and / or, the mass percent of Li20 is 2.35%, 1.55%, 1.50%, 1.77%, 1.60%, 1.62%, 2.28%, 2.27%, 2.24%, 1.60%, 1.57%, 2.85%, or 1.53%; and / or, the mass percent of CaO is 0%, 0.75%, 1.15%, or 0.92%; and / or, the mass percent of B203 is 0% or 7.07%; and / or, the mass percent of BaO is 2.42%, 2.41%, 6.94%, 0%, 2.35%, or 2.32%; and / or, the mass percent of Y203 is 0%, 1.52%, or 0.60%; and / or, the mass percent of La203 is 0%, 2.17%, or 3.69%.

13. The strengthened glass ceramic of any one of claims 1-12, wherein, the average crystallite size in the strengthened glass ceramic is 5.0 nm, 6.8 nm, 6.4 nm, 6.5 nm, 8.1 nm, 7.0 nm, 6.1 nm, 5.1 nm, or 6.2 nm; and / or the total crystalline phase content in the strengthened glass ceramic is 48.69%, 45.11%, 49.52%, 47.85%, 54.07%, 51.56%, 45.49%, 44.77%, 52.28%, 35.52%, 48.75%, or 44.33% by mass percent.

14. The strengthened glass ceramic of any one of claims 1 to 13, wherein, the strengthened glass ceramic has a Vickers hardness of 840 kgf / mm 2 , 848 kgf / mm 2 , 855 kgf / mm 2 , 879 kgf / mm 2 , 889 kgf / mm 2 , 836 kgf / mm 2 , 911 kgf / mm 2 , 897 kgf / mm 2 , 807 kgf / mm 2 , 894 kgf / mm 2 , 883 kgf / mm 2 , 873 kgf / mm 2 , 795 kgf / mm 2 , 863 kgf / mm 2 , 850 kgf / mm 2 , 856 kgf / mm 2 , or 860 kgf / mm 2 ; and / or, the strengthened glass ceramic has a fracture toughness value of 1.64 MPa-m 0.5 1.65 MPa-m 0.5 1.66 MPa-m 0.5 1.70 MPa-m 0.5 1.71 MPa-m 0.5 1.63 MPa-m 0.5 1.74 MPa-m 0.5 1.72 MPa-m 0.5 1.59 MPa-m 0.5 1.69 MPa-m 0.5 1.57 MPa-m 0.5 or 1.67 MPa-m 0.5 ; and / or, the |CT AV| of the strengthened glass ceramic is 6.68 MPa, 5.85 MPa, 12.45 MPa, 5.45 MPa, 7.33 MPa, 7.79 MPa, 10.91 MPa, 14.64 MPa, 9.98 MPa, 6.25 MPa, 13.15 MPa, 8.58 MPa, 6.33 MPa, 7.91 MPa, 10.75 MPa, 12.77 MPa, 13.58 MPa, 9.47 MPa, or 7.98 MPa; and / or, The |CT_CV| of the strengthened glass ceramic is 7.87 MPa, 6.96 MPa, 15.32 MPa, 6.84 MPa, 8.12 MPa, 9.01 MPa, 11.79 MPa, 17.92 MPa, 11.70 MPa, 7.76 MPa, 15.90 MPa, 9.45 MPa, 8.68 MPa, 9.13 MPa, 12.07 MPa, 14.12 MPa, 15.74 MPa, 10.75 MPa, or 9.02 MPa.

15. The strengthened glass ceramic of any one of claims 1 to 14, wherein, The single rod static pressure strength of the strengthened glass ceramic is greater than 800 N, wherein the single rod static pressure strength of the strengthened glass ceramic is tested by using a 10 mm diameter round head metal pressure rod to stepwise apply a load vertically downward at 10 mm / min to press the center of the main surface of the strengthened glass ceramic.

16. The strengthened glass ceramic of any one of claims 1 to 15, wherein, The strengthened glass ceramic is prepared by a chemical strengthening treatment of a glass ceramic having a fracture toughness not less than 1.40 MPa.m 0.5 The strengthened glass ceramic is prepared by a chemical strengthening treatment of a glass ceramic having a fracture toughness not less than 1.40 MPa.m 0.5 The strengthened glass ceramic is prepared by a chemical strengthening treatment of a glass ceramic having a fracture toughness not less than 1.40 MPa.m 0.5 The strengthened glass ceramic is prepared by a chemical strengthening treatment of a glass ceramic having a fracture toughness not less than 1.40 MPa.m 17. A cover glass, characterized by The cover plate glass is made of the strengthened glass ceramic according to any one of claims 1-16, or the cover plate glass comprises the strengthened glass ceramic according to any one of claims 1-16.

18. An electronic device, comprising: The electronic device comprises the strengthened glass ceramic according to any one of claims 1-16.

19. The electronic device of claim 18, wherein, The electronic device comprises a housing, and the housing comprises the strengthened glass ceramic according to any one of claims 1-16.

20. The electronic device of claim 19, wherein, The housing comprises a display screen cover plate, and the display screen cover plate comprises the strengthened glass ceramic according to any one of claims 1-16.

21. The electronic device of claim 19 or 20, wherein, The housing comprises a back cover, and the back cover comprises the strengthened glass ceramic according to any one of claims 1-16.

22. The electronic device of any of claims 19-21, wherein, The electronic device further comprises a camera assembly, the housing comprises a camera protection cover plate covering the camera assembly, and the camera protection cover plate comprises the strengthened glass ceramic according to any one of claims 1-16.

23. The electronic device of any of claims 18-22, wherein, The electronic device further comprises a middle frame, and the middle frame comprises the strengthened glass ceramic according to any one of claims 1-16.

24. A glass article, characterized by, The glass device comprises the strengthened glass ceramic according to any one of claims 1-16.

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