Transparent strengthened glass-ceramics having high depth of stress and methods of making and use thereof

Abstract

The application discloses a transparent strengthened glass ceramic with high stress depth, which contains spinel crystals and zirconia crystals in a crystal phase of the strengthened glass ceramic, and does not contain Li-containing crystals; the strengthened glass ceramic has a compressive stress region extending from a surface thereof to a compression depth, a compressive stress layer depth DOL_0 of the strengthened glass ceramic is greater than or equal to 14% of a thickness of the strengthened glass ceramic, and a tensile stress line density of the strengthened glass ceramic is greater than or equal to 25000 MPa / mm. By introducing more Li ions and Na ions into a spinel glass ceramic component, the prepared transparent spinel glass ceramic can be chemically strengthened, a transparent strengthened glass ceramic with high CS, DOL_0, CT_AV and CT_LD is obtained, and the strengthened glass ceramic exhibits excellent drop resistance.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of glass, in particular to a transparent strengthened glass ceramic with high stress depth and a preparation method and application thereof. BACKGROUND

[0002] With the gradual thinning of electronic devices, the performance requirements of the cover glass are gradually increasing. Microcrystalline glass (glass ceramic) has been widely concerned due to its good impact resistance, scratch resistance, wear resistance and other properties. Transparent spinel ceramic not only has the performance characteristics of general advanced ceramics such as high temperature resistance, corrosion resistance, wear resistance, impact resistance, high hardness, excellent insulation, etc., but also has optical properties similar to white sapphire single crystals, and has good optical transmittance in the ultraviolet, visible and infrared light bands. It is commonly used as transparent armor, missile windows, radomes, various substrate materials, new lamps and various high temperature and high pressure and corrosive environment equipment observation windows. However, spinel microcrystalline glass generally cannot be chemically strengthened and toughened, resulting in poor toughness and poor drop resistance, especially when the thickness is small (≤1mm), the brittleness is more obvious, and it is not suitable for use as an electronic cover glass that requires high impact resistance.

[0003] For electronic cover glass, it is necessary to have high CS, DOL_0, CT_AV and CT_LD, especially high CT_LD, in order to achieve good drop resistance. In order to obtain high CS, DOL_0, CT_AV and CT_LD, a certain amount of Li2O and Na2O needs to be added to the glass composition. However, with the increase of the amount of Li2O and Na2O in the spinel glass ceramic composition, crystals that affect the optical properties of the glass ceramic, such as beta quartz, beta quartz solid solution, beta-lithium spar, etc., are often precipitated in the glass. The precipitation of these crystals can easily cause the glass ceramic to fog, even lose transparency, making it difficult to obtain ideal transparent spinel glass ceramic.

[0004] It is a problem that needs to be solved by those skilled in the art to develop a new transparent spinel glass ceramic that has more Li ions and Na ions for chemical strengthening ion exchange while ensuring excellent optical properties, and to use the transparent spinel glass ceramic to prepare a strengthened glass ceramic with high CS, DOL_0, CT_AV and CT_LD, which can achieve excellent drop resistance. SUMMARY

[0005] The purpose of the present application is to provide a transparent strengthened glass ceramic with high stress depth, which has excellent drop resistance and excellent transmittance.

[0006] In order to solve the above technical problems, the technical scheme adopted by the present application is as follows:

[0007] The present application provides a transparent strengthened glass ceramic with high stress depth, the strengthened glass ceramic comprising spinel crystals and zirconia crystals in the crystalline phase thereof, and not containing Li-containing crystals;

[0008] The strengthened glass ceramic has a compressive stress region extending from the surface thereof to a compressive depth, the compressive depth of layer DOL_0 of the strengthened glass ceramic being greater than or equal to 14% of the thickness of the strengthened glass ceramic, and the tensile stress line density CT_LD of the strengthened glass ceramic being greater than or equal to 25000 MPa / mm.

[0009] The strengthened glass ceramic does not contain quartz and quartz solid solution in the crystalline phase thereof.

[0010] The tensile stress line density CT_LD of the strengthened glass ceramic is 25000-40000 MPa / mm, preferably 27000-40000 MPa / mm.

[0011] The surface compressive stress CS of the strengthened glass ceramic is greater than or equal to 650 MPa, preferably greater than or equal to 680 MPa.

[0012] The average tensile stress CT_AV of the strengthened glass ceramic is greater than or equal to 35.0 MPa, preferably greater than or equal to 39.0 MPa.

[0013] The Vickers hardness of the strengthened glass ceramic is greater than or equal to 740 HV0.3.

[0014] The fracture toughness of the strengthened glass ceramic is greater than or equal to 1.500 MPa·m 1 / 2 , preferably greater than or equal to 1.560 MPa·m 1 / 2 .

[0015] The spinel crystals comprise zinc spinel and magnesium spinel.

[0016] The transmittance of the strengthened glass ceramic at 550 nm is greater than 85.00% at a thickness of 0.7 mm.

[0017] The strengthened glass ceramic exhibits a crystallinity of at least 30.00 wt%.

[0018] The average size of the crystals in the strengthened glass ceramic is less than or equal to 15.0 nm.

[0019] The strengthened glass ceramic comprises a compressive stress layer at the surface and a tensile stress layer in the interior, the composition of the tensile stress layer of the strengthened glass ceramic, in terms of mole percent of oxides, comprising:

[0020] Li2O: 3.50-6.00 mol%,

[0021] Na2O: 2.00-4.00 mol%.

[0022] The composition of the strengthened glass ceramic compressive layer, in terms of mole percent of oxides, includes:

[0023] SiO2: 50.00-65.00 mol%,

[0024] Al2O3: 14.50-25.00 mol%,

[0025] MgO: 3.50-8.00 mol%,

[0026] ZnO: 8.00-16.00 mol%,

[0027] BaO: 0-2.00 mol%,

[0028] TiO2+ZrO2: 3.00-5.50 mol%.

[0029] In the composition of the strengthened glass ceramic compressive layer, in terms of mole percent of oxides:

[0030] 0.40≤(Al2O3+ZnO+MgO+ZrO2+TiO2) / (Li2O+Na2O+SiO2+BaO)≤0.70.

[0031] In the composition of the strengthened glass ceramic compressive layer, in terms of mole percent of oxides:

[0032] 0.43≤(Al2O3+ZnO+MgO+ZrO2+TiO2) / (Li2O+Na2O+SiO2+BaO)≤0.68.

[0033] In the composition of the strengthened glass ceramic compressive layer, in terms of mole percent of oxides:

[0034] Na2O / (Li2O+Na2O+SiO2+BaO)≥0.035;

[0035] and / or

[0036] Li2O / (Li2O+Na2O+SiO2+BaO)≥0.054.

[0037] In the composition of the strengthened glass ceramic compressive layer, in terms of mole percent of oxides:

[0038] 0.035≤ Na2O / (Li2O + Na2O + SiO2 + BaO) ≤ 0.070;

[0039] and / or

[0040] 0.054≤ Li2O / (Li2O + Na2O + SiO2 + BaO) ≤ 0.090.

[0041] wherein the composition of the strengthened glass-ceramic, in mole percent on an oxide basis, comprises:

[0042] SiO2: 50.00-63.00 mol%, preferably 50.00-57.00 mol%; and / or

[0043] Al2O3: 14.50-20.00 mol%, preferably 15.00-19.00 mol%; and / or

[0044] MgO: 3.90-7.60 mol%, preferably 4.00-7.50 mol%; and / or

[0045] ZnO: 8.00-15.50 mol%, preferably 9.00-15.20 mol%; and / or

[0046] BaO: 0-1.50 mol%, preferably 1.00-1.35 mol%; and / or

[0047] Li2O: 3.50-5.00 mol%, preferably 4.00-5.00 mol%; and / or

[0048] Na2O: 2.30-3.60 mol%, preferably 3.00-3.60 mol%; and / or

[0049] TiO2: 0-2.00 mol%, preferably 0.30-1.30 mol%; and / or

[0050] ZrO2: 2.50-5.00 mol%, preferably 2.90-4.20 mol%.

[0051] The present application also provides a method for preparing a transparent strengthened glass-ceramic with high stress depth, comprising the following steps:

[0052] (1) mixing according to the formula to prepare a glass precursor;

[0053] (2) sequentially performing nucleation treatment and crystallization treatment on the prepared glass precursor to obtain a transparent spinel glass-ceramic;

[0054] (3) performing one or more steps of ion exchange in a salt bath on the transparent spinel glass-ceramic prepared in step (2) to obtain the strengthened glass-ceramic.

[0055] In step (2), the nucleation temperature is 700-800℃, and the nucleation treatment time is 30-1440 min.

[0056] In step (2), the nucleation temperature is 700-800℃, and the nucleation treatment time is 30-1440 min.

[0057] In step (2), the nucleation temperature is 700-800℃, and the nucleation treatment time is 30-1440 min.

[0058] In step (2), the nucleation temperature is 700-800℃, and the nucleation treatment time is 30-1440 min.

[0059] In step (2), the nucleation temperature is 700-800℃, and the nucleation treatment time is 30-1440 min.

[0060] In step (3), the first step of ion exchange is performed at a temperature of 400-500℃ for 0.5-48 h in a salt bath composed of 50-100wt% NaNO3+0-50wt% KNO3.

[0061] In step (3), the first step of ion exchange is performed at a temperature of 400-500℃ for 0.5-48 h in a salt bath composed of 50-100wt% NaNO3+0-50wt% KNO3.

[0062] In step (3), the first step of ion exchange is performed at a temperature of 400-500℃ for 0.5-48 h in a salt bath composed of 50-100wt% NaNO3+0-50wt% KNO3.

[0063] In step (3), the first step of ion exchange is performed at a temperature of 400-500℃ for 0.5-48 h in a salt bath composed of 50-100wt% NaNO3+0-50wt% KNO3.

[0064] To improve the service life of the salt bath, a salt bath protective agent in an amount of 0.1-5wt% based on the mass of the salt bath can be added to the salt bath, and the salt bath protective agent comprises a substance for passivation, precipitation or absorption of Li + .

[0065] The application also provides an electronic terminal as a consumer product, comprising:

[0066] a housing comprising a front surface, a rear surface and side surfaces;

[0067] and an electronic assembly partially located within the housing, the electronic assembly comprising a display device located at or adjacent to a front surface of the housing;

[0068] the front surface or / and the rear surface or / and the side surface comprises the strengthened glass-ceramic material;

[0069] further comprising a cover article comprising the strengthened glass-ceramic material covering the front surface of the housing or located on the display device;

[0070] the electronic terminal as a consumer product comprises a mobile phone, a tablet computer, a photovoltaic device, or other electronic terminal (such as an electronic watch, etc.).

[0071] The transparent spinel glass-ceramic material and the strengthened glass-ceramic material in the present application both have excellent performance, and can be contained / used in other articles, such as watches, transparent armors, missile windows, radomes, substrate materials, new lamps, observation windows of equipment under high temperature and high pressure and corrosive environment, display protection materials and appearance shell protection materials of portable smart electronic devices (including mobile phones, tablet computers, electronic watches, etc.), building articles, transportation articles (such as cars, trains, airplanes, marine vehicles, etc.), appliance articles, or any article requiring certain transparency, scratch resistance, impact resistance, wear resistance, or a combination thereof.

[0072] Compared with the prior art, the present application has the following beneficial effects:

[0073] 1. The composition of the spinel glass-ceramic material is optimized in the present application, more Li ions and Na ions for chemical strengthening ion exchange are introduced into the spinel glass-ceramic, and a spinel glass-ceramic without impurity crystal phases (such as Li-containing crystal phase, quartz, quartz solid solution, etc.) is obtained, and the glass-ceramic does not appear phenomena such as fogging and devitrification, which ensures that the glass-ceramic material has excellent transmittance.

[0074] By introducing more Li ions and Na ions into the composition of the spinel glass-ceramic, the prepared spinel glass-ceramic can be chemically strengthened, and a transparent strengthened glass-ceramic with high CS, DOL_0, CT_AV and CT_LD is obtained, which exhibits excellent drop performance.

[0075] 2. After performance testing of the glass-ceramic material prepared in the present application, it is found that the transparent spinel glass-ceramic material in the present application has a high crystallinity, which brings excellent mechanical properties to the glass-ceramic material.

[0076] 3. The application also provides a preparation method of spinel glass ceramics, the process method provided by the application controls the process parameters of the crystallization process and the nucleation process, and sets the heating rate parameter requirement, so that the spinel glass ceramics without impurity crystal phases (such as Li crystal phase, quartz, quartz solid solution and the like) is finally obtained, and the glass ceramic material has excellent optical performance. BRIEF DESCRIPTION OF DRAWINGS

[0077] Figure 1 It is a whole machine falling experiment effect diagram.

[0078] Figure 2 It is the relationship between Li2O content and CT_LD, D represents the comparative example, and S represents the example.

[0079] Figure 3 It is the DSC spectrum of the glass precursor with different Li content.

[0080] Figure 4 It is the XRD spectrum of the glass ceramic prepared by using different heating rates during the crystallization treatment.

[0081] Figure 5 It is the photo of the glass ceramic prepared by using different heating rates during the crystallization treatment, wherein:

[0082] (a) is the glass without heat treatment;

[0083] (b) is the glass ceramic prepared by using 5 ℃ / min heating rate during the crystallization treatment;

[0084] (c) is the glass ceramic prepared by using 20 ℃ / min heating rate during the crystallization treatment;

[0085] (d) is the glass ceramic prepared by using 30 ℃ / min heating rate during the crystallization treatment.

[0086] Figure 6 It is the transmittance display diagram of the glass ceramic prepared by using different heating rates during the crystallization treatment to the light with a wavelength of 550 nm. DETAILED DESCRIPTION

[0087] The application will be further described in detail below by combining with the examples and the drawings.

[0088] Firstly, the related special names and related measurement methods involved in the application are explained as follows:

[0089] Glass ceramic: also known as microcrystalline glass, is a kind of solid composite material containing glass phase and microcrystalline phase by targeted and controlled crystallization of base glass.

[0090] Strengthened glass-ceramics: solid composite material obtained after chemical strengthening of glass-ceramics. During high-temperature chemical strengthening treatment, alkali metal ions with large ionic radius (such as potassium ions, sodium ions) in the salt bath will replace the alkali metal ions with small ionic radius (such as sodium ions, lithium ions) in the glass-ceramics, thereby generating an exchange ion volume difference and generating a compressive stress on the surface of the glass-ceramics.

[0091] Surface compressive stress CS: After chemical strengthening of glass-ceramics, the alkali metal ions with small radius on the surface are replaced by alkali metal ions with large radius. Due to the jamming effect of alkali metal ions with large radius, a compressive stress is generated on the surface of the glass, which is called surface compressive stress.

[0092] Depth of compressive stress layer DOL_0: refers to the distance from the surface of the strengthened glass-ceramics to the position where the compressive stress is zero.

[0093] Tensile stress linear density CT_LD: the ratio of the sum of tensile stress obtained by SLP stress instrument test to the thickness of glass-ceramics. After chemical strengthening, a tensile stress layer is formed inside the strengthened glass-ceramics, which has an upper boundary at a certain distance from the upper surface of the strengthened glass-ceramics and a lower boundary at a certain distance from the lower surface of the strengthened glass-ceramics. The curve drawn with the tensile stress Y axis and the distance from the upper boundary X axis at a certain point in the tensile stress layer, which is perpendicular to the upper boundary and the lower boundary and the upper and lower endpoints fall on the upper boundary and the lower boundary respectively, is called tensile stress curve. The ratio of the definite integral of the tensile stress curve to the thickness of the strengthened glass-ceramics is called tensile stress linear density, that is, the ratio of the sum of the tensile stress of the strengthened glass-ceramics measured by SLP-2000 stress instrument to the thickness of the glass.

[0094] The compressive stress and tensile stress in chemically strengthened glass are in equilibrium, and the tensile stress area of SLP-2000 stress instrument is more accurate, so the tensile stress integral and thickness ratio are used to represent the stress contained in unit thickness of glass-ceramics, which is used to represent the stress degree of chemically strengthened glass-ceramics.

[0095] CT_AV: refers to the average value of all tensile stresses in the tensile stress area.

[0096] Nucleation temperature: the temperature at which crystal nuclei form.

[0097] Crystallization temperature: the temperature at which the target crystal growth rate is controllable.

[0098] Transmittance: the ratio of the intensity of the transmitted part to the intensity of the incident light when light of a certain wavelength is irradiated onto the surface of the glass.

[0099] Fogging: due to the large crystal or phase separation in glass-ceramics, it appears in a semi-transparent state between transparent and opaque.

[0100] Opal: The glass completely loses the transparent property and cannot see any picture on the back of the glass due to the large crystal or phase separation in the glass-ceramic.

[0101] Differential scanning calorimetry (DSC) test:

[0102] After the sample is ground, it is passed through a 200-mesh screen;

[0103] The test conditions are: room temperature ~ 1100 DEG C, 10 DEG C / min heating rate;

[0104] The test instrument is Mettler-Toledo TGA / DSC3+ thermogravimetric and simultaneous thermal analyzer.

[0105] Test of transmittance:

[0106] First, the crystallized glass sheet is cleaned in an ultrasonic cleaning machine, and the cleaning conditions include:

[0107] Cleaning time: 5-10 min;

[0108] The cleaning agent used is a commonly used washing agent diluted 10 times;

[0109] Cleaning temperature: 45 DEG C-65 DEG C;

[0110] Cleaning frequency: 20KHZ-40KHZ.

[0111] Then, the transmittance of the glass at different wavelengths is tested by using a haze meter, and the test is carried out according to the standard of GB / T 7962.12-2010 Colorless Optical Glass Test Method Part 12: Spectral In-Transmission Ratio;

[0112] The haze meter used in the present application is a Japan Konica Minolta Spectrophotometer CM-3600A.

[0113] Whole machine drop test:

[0114] First, 120-mesh sandpaper is attached to a 160g Huawei P30 model machine, and a 50*50*0.7mm strengthened glass ceramic sheet to be tested is placed directly below the model machine, and then the model machine is dropped from a specified height in the form of impact.

[0115] Each batch of samples is at least 10 or more, the drop height starts from 0.4m, and the sample is subjected to a drop impact, if it is not broken, the height is increased by 0.1m each time and dropped again, until the glass is broken, and the average value of the breaking height is taken as the anti-drop height.

[0116] In the present application, stress measurement can be measured by FSM6000 and SLP2000 produced by Orihara Company respectively on the surface high stress area and deep low stress area, and the stress curve is fitted by using PMC software to obtain the corresponding test results. Of course, other stress testers that can measure the surface high stress area and deep low stress area can also be used.

[0117] Secondly, the present application provides a transparent spinel glass ceramic, which comprises, in terms of mole percentage of oxides:

[0118] Li2O: 3.50-6.00 mol%,

[0119] Na2O: 2.00-4.00 mol%,

[0120] The crystal phase of the glass ceramic contains spinel crystals and zirconia crystals, and does not contain Li-containing crystals.

[0121] The present application has carried out targeted research on the components of the glass ceramic material. In order to enable the glass ceramic material to obtain toughening through chemical strengthening, obtain high CS, DOL_0, CT_AV and CT_LD, and improve the impact and drop resistance, it is necessary to add alkali metal oxides, especially Li2O (lithium oxide) and Na2O (sodium oxide) to the components. However, with the increase of the addition amount of Li2O and Na2O, impurity crystals affecting the optical performance of the glass ceramic, such as beta quartz, beta quartz solid solution, beta-spodumene and other crystal phases, are often precipitated in the glass. Figure 3 This is well confirmed by the fact that, with the increase of the content of Li2O, Figure 3 The single peak of spinel gradually changes to multiple peaks (spinel peak + other impurity crystal phases) in the middle. The precipitation of these impurity crystals easily makes the crystallized glass appear foggy, even devitrify, which seriously affects the optical performance of the glass ceramic.

[0122] For this problem, the prior art usually adopts the way of reducing the addition amount of Li2O and Na2O to avoid the precipitation of too much beta quartz, beta quartz solid solution, beta-spodumene and other crystal phases, thereby avoiding the fogging and devitrification of the glass ceramic. However, this way will inevitably result in that the CS, DOL_0, CT_AV and CT_LD obtained by strengthening the glass ceramic are all relatively low, and the drop resistance is difficult to reach an excellent level.

[0123] In order to obtain a transparent strengthened spinel glass ceramic with high CS, DOL_0, CT_AV and CT_LD, and improve the drop resistance of the spinel glass ceramic, the present application optimizes the components.

[0124] The present application can obtain spinel glass ceramics without impurity crystal phases (such as Li-containing crystal phases, quartz, quartz solid solution and the like) in the case of introducing more Li2O and Na2O, the glass ceramics do not appear fogging and devitrification and the like, and the glass ceramics material has excellent transmittance. By introducing more Li ions and Na ions into the spinel glass ceramic composition, the prepared spinel glass ceramics can be chemically strengthened, and transparent strengthened glass ceramics with high CS, DOL_0, CT_AV and CT_LD are obtained, and the transparent strengthened glass ceramics has excellent drop resistance.

[0125] The transparent spinel glass ceramics provided by the present application has the following characteristics:

[0126] The content of Li2O includes 3.50-6.00 mol% and all ranges and subranges therebetween, such as 3.50-5.00 mol%, 4.50-5.00 mol%, 4.50-5.50 mol%, 3.50-4.50 mol%, 4.00-5.00 mol%, 4.50-6.00 mol%, 5.00-6.00 mol%, 5.50-6.00 mol%, 3.50-4.00 mol%, 3.50-4.40 mol%, 3.80-5.50 mol%, 3.90-4.00 mol%, 3.60-4.40 mol%, 4.80-5.90 mol% and the like; in some embodiments, the content of Li2O can be 3.50 mol%, 3.60 mol%, 3.70 mol%, 3.80 mol%, 3.90 mol%, 4.00 mol%, 4.10 mol%, 4.20 mol%, 4.30 mol%, 4.40 mol%, 4.50 mol%, 4.60 mol%, 4.70 mol%, 4.80 mol%, 4.90 mol%, 5.00 mol%, 5.10 mol%, 5.20 mol%, 5.30 mol%, 5.40 mol%, 5.50 mol%, 5.60 mol%, 5.70 mol%, 5.80 mol%, 5.90 mol%, 6.00 mol% and the like.

[0127] The content of Na20 includes 2.00-4.00 mol% and all ranges and subranges therebetween, such as 2.30-3.60 mol%, 3.00-3.60 mol%, 2.5-3.00 mol%, 2.40-3.80 mol%, 2.00-2.60 mol%, 2.00-2.80 mol%, 2.50-3.20 mol%, 2.50-3.60 mol%, 2.50-3.10 mol%, 2.50-3.40 mol%, 2.50-3.80 mol%, 2.80-3.50 mol%, 2.10-3.90 mol%, etc.; in some embodiments, the content of Na20 can be 2.00 mol%, 2.10 mol%, 2.20 mol%, 2.30 mol%, 2.40 mol%, 2.50 mol%, 2.60 mol%, 2.70 mol%, 2.80 mol%, 2.90 mol%, 3.00 mol%, 3.10 mol%, 3.20 mol%, 3.30 mol%, 3.40 mol%, 3.50 mol%, 3.60 mol%, 3.70 mol%, 3.80 mol%, 3.90 mol%, 4.00 mol%, etc.

[0128] In some embodiments, the glass-ceramic is free of quartz and quartz solid solution in the crystalline phase. The presence of quartz and quartz solid solution can affect the optical performance of the spinel glass-ceramic, and easily make the crystallized glass appear foggy or even lose transparency.

[0129] In some embodiments, the glass-ceramics exhibit a crystallinity of at least 30.00 wt%; and the average crystal size in the glass-ceramics is less than or equal to 15.0 nm. By controlling to achieve a sufficiently high crystallinity, the intrinsic strength of the glass-ceramics can be significantly improved, while by controlling the crystal size to ensure that the crystal size is sufficiently small, the light transmittance of the glass-ceramics can be significantly improved, ensuring that the glass-ceramics have excellent optical performance. The glass-ceramics of the present application exhibit a crystallinity of at least 30.00 wt%, including all ranges and subranges greater than or equal to 30.00 wt% and therebetween, such as 30.00-50.00 wt%, 30.00-40.00 wt%, 40.00-50.00 wt%, 35.00-40.00 wt%, 30.00-44.00 wt%, 31.00-35.00 wt%, 42.00-45.00 wt%, 31.00-37.00 wt%, 30.00-38.00 wt%, 30.00-39.00 wt%, etc.; in some embodiments, the crystallinity of the glass-ceramics of the present application can be 30.00 wt%, 31.00 wt%, 32.00 wt%, 33.00 wt%, 34.00 wt%, 35.00 wt%, 36.00 wt%, 37.00 wt%, 38.00 wt%, 39.00 wt%, 40.00 wt%, 41.00 wt%, 42.00 wt%, 43.00 wt%, 44.00 wt%, 45.00 wt%, 46.00 wt%, 47.00 wt%, 48.00 wt%, 49.00 wt%, 50.00 wt%, etc. At the same time, the average crystal size in the glass-ceramics of the present application is less than or equal to 15.0 nm, including all ranges and subranges less than or equal to 15.0 nm and therebetween, such as 5.0-10.0 nm, 5.0-11.0 nm, 5.0-13.0 nm, 4.0-10.0 nm, 3.0-15.0 nm, 6.0-13.0 nm, 7.0-12.0 nm, 2.0-10.0 nm, 5.0-14.0 nm, 4.0-9.0 nm, etc.; in some embodiments, the average crystal size of the glass-ceramics of the present application can be 2.0 nm, 3.0 nm, 4.0 nm, 5.0 nm, 6.0 nm, 7.0 nm, 9.0 nm, 10.0 nm, 11.0 nm, 12.0 nm, 13.0 nm, 14.0 nm, 15.0 nm, etc.

[0130] In some embodiments, the spinel crystals include zinc spinel and magnesium spinel, and / or a solid solution of zinc spinel (ZnAl204) and magnesium spinel (MgAl204). Zinc spinel (ZnAl204) is a cubic mineral, and according to the Mohs hardness scale, the hardness of spinel is 7.5-8, and the measured density is 4.38-4.60 g / cm 3At ambient pressure, the Young's modulus of zinc spinel is 290 GPa, the shear modulus is 146 GPa, and the refractive index is 1.79-1.80. Zinc spinel (ZnAl204) forms a solid solution with magnesium spinel (MgAl204), and the properties of the solid solution spinel are nearly identical to those of zinc spinel (ZnAl204). Differences include (magnesium spinel vs. zinc spinel): (a) lower refractive index (magnesium spinel: 1.72 vs. zinc spinel: 1.79-1.80); (b) lower density (magnesium spinel: 3.6-4.1 g / cm 3 vs. zinc spinel: 4.4-4.6 g / cm 3 )(c) lower Young's modulus (magnesium spinel: 283 GPa vs. zinc spinel: 290 GPa); (d) higher shear modulus (magnesium spinel: 155 GPa vs. zinc spinel: 146 GPa). The high hardness, high density, and high elastic constants of zinc-magnesium spinel result in superior mechanical properties of the composite glass-ceramics over the precursor glass, as the composite glass-ceramics are a function of the mechanical properties of each component phase. Zinc-magnesium spinel glass-ceramics exhibit excellent crack growth resistance and scratch resistance.

[0131] In some embodiments, the glass-ceramics have a transmittance greater than 85.00% at a wavelength of 550 nm at a thickness of 0.7 mm. The glass-ceramics of the present disclosure are transparent in the visible range, exhibiting a transmittance of at least about 85.00% when at a wavelength of 550 nm. The glass-ceramics of the present disclosure have a transmittance greater than 85.00% at a wavelength of 550 nm, including greater than 85.00% and all ranges and sub-ranges therebetween, such as 86.00%, 87.00%, 88.00%, 89.00%, 90.00%, 91.00%, 92.00%, 93.00%, and the like.

[0132] In some embodiments, the glass-ceramics of the present disclosure further comprise the following components, in mole percent on an oxide basis:

[0133] Si02: 50.00-65.00 mol%,

[0134] Al203: 14.50-25.00 mol%,

[0135] MgO: 3.50-8.00 mol%,

[0136] ZnO: 8.00-16.00 mol%,

[0137] BaO: 0-2.00 mol%,

[0138] Ti02+ Zr02: 3.00-5.50 mol%.

[0139] Further, the glass-ceramic according to the present application comprises the following components in terms of mole percentage of oxide:

[0140] SiO2: 50.00-63.00 mol%, preferably 50.00-57.00 mol%; and / or

[0141] Al2O3: 14.50-20.00 mol%, preferably 15.00-19.00 mol%; and / or

[0142] MgO: 3.90-7.60 mol%, preferably 4.00-7.50 mol%; and / or

[0143] ZnO: 8.00-15.50 mol%, preferably 9.00-15.20 mol%; and / or

[0144] BaO: 0-1.50 mol%, preferably 1.00-1.35 mol%; and / or

[0145] Li2O: 3.50-5.00 mol%, preferably 4.00-5.00 mol%; and / or

[0146] Na2O: 2.30-3.60 mol%, preferably 3.00-3.60 mol%; and / or

[0147] TiO2: 0-2.00 mol%, preferably 0.30-1.30 mol%; and / or

[0148] ZrO2: 2.50-5.00 mol%, preferably 2.90-4.20 mol%.

[0149] In the present application:

[0150] SiO2(silica) and Al2O3(alumina) are the main components constituting the glass network structure, and sufficient SiO2and Al2O3can ensure that the glass has high network structure strength, which is conducive to ensuring that the glass has high intrinsic strength and thermal stability; too high SiO2and Al2O3content will lead to increased difficulty in glass melting. Al2O3not only provides Al elements for spinel crystal precipitation, but also can increase the surface compressive stress during chemical strengthening treatment.

[0151] MgO (magnesium oxide) and ZnO (zinc oxide) can provide the Mg and Zn elements necessary for spinel crystals formed in the glass-ceramics. MgO can increase the high-temperature viscosity of the glass melt, reduce the crystallization tendency and crystallization rate, and improve the chemical stability and mechanical strength of the glass; ZnO, as a network intermediate, can consume free oxygen in the glass to form [ZnO4] into the structural network of the glass, making the structure of the glass more stable, and too much of it can make the glass prone to crystallization. Therefore, adjusting the ratio of MgO and ZnO can control the precipitation rate of the crystals.

[0152] BaO (barium oxide) can accelerate the melting of the glass, but too much of it can produce secondary bubbles, making it difficult to clarify.

[0153] TiO2 (titanium oxide) and ZrO2 (zirconium oxide) are used as nucleating agents. ZrO2 can increase the viscosity and chemical stability of the glass, but too much of it can make the glass difficult to melt; TiO2 can improve the chemical stability of the glass and increase the uniformity of the glass melting, but too much of it can cause the glass to color and increase the refractive index of the glass. The combination of TiO2 and ZrO2 can have a good nucleation effect.

[0154] The content of SiO2 includes 50.00-65.00 mol% and all ranges and subranges therebetween, such as 50.00-63.00 mol%, 50.00-65.00 mol%, 50.00-60.00 mol%, 51.00-63.00 mol%, 52.00-65.00 mol%, 53.00-65.00 mol%, 55.00-65.00 mol%, 50.00-57.00 mol%, 52.00-57.00 mol%, etc. In some embodiments, the content of SiO2 can be 50.00 mol%, 51.00 mol%, 52.00 mol%, 53.00 mol%, 54.00 mol%, 55.00 mol%, 56.00 mol%, 57.00 mol%, 58.00 mol%, 59.00 mol%, 60.00 mol%, 61.00 mol%, 62.00 mol%, 63.00 mol%, 64.00 mol%, 65.00 mol%, etc.

[0155] The content of AI2O3includes 14.50-25.00 mol% and all ranges and subranges therebetween, such as 14.50-20.00 mol%, 15.00-19.00 mol%, 14.50-20.00 mol%, 15.50-20.00 mol%, 15.00-24.00 mol%, 14.90-23.00 mol%, 16.00-24.00 mol%, 17.00-25.00 mol%, 18.00-25.00 mol%, etc. In some embodiments, the content of AI2O3may be 14.50 mol%, 14.90 mol%, 15.00 mol%, 15.50 mol%, 16.00 mol%, 17.00 mol%, 18.00 mol%, 19.00 mol%, 20.00 mol%, 23.00 mol%, 24.00 mol%, 25.00 mol%, etc.

[0156] The content of MgO includes 3.50-8.00 mol% and all ranges and subranges therebetween, such as 4.00-7.50 mol%, 3.90-7.60 mol%, 3.50-4.00 mol%, 3.50-5.00 mol%, 3.50-6.00 mol%, 3.50-7.00 mol%, 4.50-6.00 mol%, 5.50-8.00 mol%, 6.50-8.00 mol%, etc. In some embodiments, the content of MgO can be 3.50 mol%, 3.90 mol%, 4.00 mol%, 4.50 mol%, 5.00 mol%, 5.50 mol%, 6.00 mol%, 6.50 mol%, 7.00 mol%, 7.50 mol%, 7.60 mol%, 8.00 mol%, etc.

[0157] The content of ZnO includes 8.00-16.00 mol% and all ranges and subranges therebetween, such as 8.00-15.50 mol%, 9.00-15.20 mol%, 8.00-13.00 mol%, 9.00-16.00 mol%, 10.00-16.00 mol%, 8.00-10.00 mol%, 8.00-11.00 mol%, 8.00-12.00 mol%, 9.00-14.00 mol%, 9.00-12.00 mol%, etc. In some embodiments, the content of ZnO can be 8.00 mol%, 9.00 mol%, 10.00 mol%, 11.00 mol%, 12.00 mol%, 13.00 mol%, 14.00 mol%, 15.20 mol%, 15.50 mol%, 16.00 mol%, etc.

[0158] The content of BaO includes 0 to 2.00 mol% and all ranges and subranges therebetween, such as 0 to 1.50 mol%, 1.00 to 1.40 mol%, 0 to 1.00 mol%, 1.00 to 2.00 mol%, 1.10 to 2.00 mol%, 1.20 to 2.00 mol%, 1.10 to 1.50 mol%, 1.20 to 1.80 mol%, etc. In some embodiments, the content of BaO can be 0 mol%, 1.00 mol%, 1.10 mol%, 1.20 mol%, 1.40 mol%, 1.50 mol%, 1.80 mol%, 2.00 mol%, etc.

[0159] The content of Ti02+ Zr02includes 3.00 to 5.50 mol% and all ranges and subranges therebetween, such as 3.00 to 5.00 mol%, 3.50 to 5.00 mol%, 4.50 to 5.00 mol%, 3.10 to 4.50 mol%, 3.30 to 4.70 mol%, 3.70 to 4.50 mol%, 3.10 to 4.80 mol%, 4.00 to 5.00 mol%, 3.00 to 4.20 mol%, 3.20 to 5.10 mol%, 3.40 to 5.40 mol%, 3.70 to 5.20 mol%, 3.00 to 4.00 mol%, etc. In some embodiments, the content of Ti02+ Zr02may be 3.00 mol%, 3.10 mol%, 3.20 mol%, 3.30 mol%, 3.40 mol%, 3.50 mol%, 3.70 mol%, 4.00 mol%, 4.20 mol%, 4.50 mol%, 4.70 mol%, 4.80 mol%, 5.00 mol%, 5.10 mol%, 5.20 mol%, 5.40 mol%, 5.50 mol%, etc.

[0160] The content of Ti02includes 0-2.00 mol% and all ranges and sub-ranges therebetween, such as 0.10-1.00 mol%, 0.50-1.00 mol%, 0.20-1.90 mol%, 0.40-1.20 mol%, 0.60-1.50 mol%, 0.80-1.00 mol%, 0.30-1.80 mol%, 0.20-1.50 mol%, 0.30-1.30 mol%, 0.10-1.70 mol%, etc. In some embodiments, the content of Ti02may be 0 mol%, 0.10 mol%, 0.20 mol%, 0.30 mol%, 0.40 mol%, 0.50 mol%, 0.60 mol%, 0.80 mol%, 0.90 mol%, 1.00 mol%, 1.20 mol%, 1.30 mol%, 1.50 mol%, 1.70 mol%, 1.80 mol%, 1.90 mol%, 2.00 mol%, etc.

[0161] The content of Zr02includes 2.50-5.00 mol% and all ranges and sub-ranges therebetween, such as 2.60-4.50 mol%, 2.70-4.50 mol%, 2.90-4.20 mol%, 2.90-3.50 mol%, 2.80-3.70 mol%, 2.50-3.10 mol%, 2.60-4.60 mol%, 3.50-5.00 mol%, 4.50-5.00 mol%, 3.10-4.50 mol%, 3.20-4.30 mol%, 2.90-3.80 mol%, 2.70-3.80 mol%, etc. In some embodiments, the content of Zr02may be 2.50 mol%, 2.60 mol%, 2.70 mol%, 2.80 mol%, 2.90 mol%, 3.10 mol%, 3.20 mol%, 3.50 mol%, 3.70 mol%, 3.80 mol%, 4.20 mol%, 4.30 mol%, 4.50 mol%, 4.60 mol%, 5.00 mol%, etc.

[0162] After the ingredients are completed, a clarifying agent is added to the mixture. The clarifying agent is not particularly limited and can be sodium chloride (NaCl), tin oxide, etc. The amount of clarifying agent is not more than 2 wt% of the weight of the mixture, such as 20 g of clarifying agent for 1 kg of mixture prepared according to the recipe. The clarifying agent is an additional auxiliary ingredient added to the ingredients.

[0163] In some embodiments, the glass-ceramic comprises, in mole percent on an oxide basis:

[0164] 0.40 < (Al203+ZnO+MgO+Zr02+Ti02) / (Li20+Na20+Si02+BaO) < 0.70. In the present application, by configuring the crystallizable glass to have this specified ratio, the glass-ceramics made with these crystallizable glasses can be provided with the properties described in the present application, including the composition and / or amount and / or structure of gahnite and / or magnesio- pliopite. For example, the components in the glass-ceramics can be specified to satisfy the above molar ratio such that the glass-ceramics contain gahnite, magnesio-pliopite and glass phase, thereby affecting the properties and / or characteristics of the glass-ceramics made therefrom. For example, the crystallinity of the glass-ceramics can be enhanced to have more excellent intrinsic strength, while also achieving higher transmittance, and ion exchange can be performed quickly and efficiently. By configuring the crystallizable glass in this way, the ratio allows for practical transformation processes (e.g., nucleation and crystallization temperatures and / or times) while allowing the formation of glass-ceramics characterized by the desired excellent optical properties and intrinsic strength that are reproducibly and reliably achieved. The ratio of (Al203+ZnO+MgO+Zr02+Ti02) / (Li20+Na20+Si02+BaO) includes 0.40 to 0.70 and all ranges and subranges therebetween, such as 0.41 to 0.51, 0.43 to 0.68, 0.42 to 0.60, 0.43 to 0.55, 0.44 to 0.58, 0.42 to 0.68, 0.45 to 0.69, 0.46 to 0.62, 0.41 to 0.54, 0.43 to 0.54, 0.44 to 0.59, 0.49 to 0.70, and the like. In some embodiments, the ratio of (Al203+ZnO+MgO+Zr02+Ti02) / (Li20+Na20+Si02+BaO) can be 0.40, 0.41, 0.42, 0.43, 0.44, 0.45, 0.46, 0.47, 0.48, 0.49, 0.50, 0.51, 0.52, 0.53, 0.54, 0.55, 0.56, 0.57, 0.58, 0.59, 0.60, 0.61, 0.62, 0.63, 0.64, 0.65, 0.66, 0.67, 0.68, 0.69, 0.70, and the like.

[0165] In some embodiments, the glass-ceramics comprise, in mole percent on an oxide basis:

[0166] Na20 / (Li20+Na20+Si02+BaO) > 0.035; and / or Li20 / (Li20+Na20+Si02+BaO) > 0.054. In some embodiments, the glass-ceramics comprise, in mole percent on an oxide basis:

[0167] The relationship between Na2O and Li2O and other components is studied, and it is found that by controlling the amount of Na2O and Li2O and other components between the components within the specified ratio range, the glass ceramic can have excellent ion exchange ability, and the obtained transparent spinel glass ceramic can have high CS, DOL_0, CT_AV and CT_LD through chemical strengthening ion exchange.

[0168] The ratio of Na2O / (Li2O+Na2O+SiO2+BaO) includes all ranges and subranges greater than or equal to 0.035, such as 0.035-0.070, 0.039-0.058, 0.035-0.051, 0.035-0.052, 0.035-0.055, 0.040-0.060, 0.055-0.060, 0.038-0.052, etc. In some embodiments, the ratio of Na2O / (Li2O+Na2O+SiO2+BaO) can be 0.035, 0.036, 0.037, 0.038, 0.039, 0.040, 0.043, 0.045, 0.048, 0.050, 0.051, 0.052, 0.055, 0.058, 0.060, 0.063, 0.065, 0.068, 0.070, etc.

[0169] The ratio of Li2O / (Li2O+Na2O+SiO2+BaO) includes all ranges and subranges greater than or equal to 0.054, such as 0.054-0.090, 0.055-0.080, 0.056-0.074, 0.058-0.073, 0.056-0.071, 0.059-0.077, 0.055-0.065, 0.055-0.075, etc. In some embodiments, the ratio of Li2O / (Li2O+Na2O+SiO2+BaO) can be 0.054, 0.055, 0.056, 0.058, 0.059, 0.060, 0.063, 0.065, 0.068, 0.070, 0.071, 0.073, 0.074, 0.075, 0.077, 0.080, 0.083, 0.085, 0.088, 0.090, etc.

[0170] Thirdly, the application provides a preparation method of transparent spinel glass ceramic, comprising the following steps:

[0171] (1) mixing according to the material formula to prepare a glass precursor;

[0172] (2) sequentially performing nucleation treatment and crystallization treatment on the prepared glass precursor to obtain the above-mentioned transparent spinel glass ceramic.

[0173] In the present application, the raw materials are mixed according to the above formula for 30 minutes, and then a clarifying agent is added as needed. The mixture is melted in a platinum-gold crucible at 1650°C for 20 hours, and then poured into a mold for shaping. After cooling to 900°C, the shaped product is annealed in an annealing furnace at 600°C for 6 hours, and then cooled to room temperature in the furnace. The glass precursor is obtained. The glass precursor is subjected to nucleation treatment and crystallization treatment in sequence, and the transparent spinel glass ceramic is obtained.

[0174] In order to obtain the transparent spinel glass ceramic product of the present application, the nucleation temperature is 700-800°C, and the nucleation treatment time is 30-1440 min. In the crystallization treatment, the crystallization temperature is 900-1000°C, and the crystallization treatment time is 5-1440 min. The nucleation treatment time refers to the time for maintaining the temperature after the crystallization furnace is heated to the set nucleation temperature at a set heating rate. The crystallization treatment time refers to the time for maintaining the temperature after the crystallization furnace is heated to the set crystallization temperature at a set heating rate.

[0175] The glass precursor is placed in a crystallization furnace, and heated to the nucleation temperature at a heating rate of 5-20°C / min, and maintained for 30-1440 min for nucleation treatment to form a sufficient number of crystal nuclei to ensure the crystallinity of the glass ceramic. After the nucleation treatment, the temperature is increased to the crystallization temperature at a heating rate of more than 20°C / min, and maintained for 5-1440 min for crystallization treatment to precipitate the required zinc spinel and magnesium spinel, while effectively inhibiting the precipitation of impurity crystal phases. After the crystallization treatment, the furnace is cooled to room temperature. By adjusting the heating rate, temperature and time at different treatment stages to adapt to the composition of the glass ceramic within the above range, it can be ensured that no impurity crystal phase affecting the transmittance of the spinel glass ceramic is precipitated, and the glass ceramic does not appear to be foggy and devitrified.

[0176] The nucleation temperature includes all ranges and sub-ranges between 700-800°C, such as 710-790°C, 700-720°C, 700-730°C, 700-740°C, 700-750°C, 700-760°C, 730-800°C, 740-800°C, 750-800°C, 760-800°C, etc. The nucleation treatment time includes all ranges and sub-ranges between 30-1440 min, such as 30-300 min, 30-200 min, 30-700 min, 30-500 min, 60-120 min, 80-144 min, 90-1200 min, 100-1100 min, 300-440 min, 100-500 min, 200-600 min, 300-540 min, 100-440 min, 300-440 min, etc.

[0177] The crystallization temperature includes 900-1000°C and all ranges and subranges therebetween, such as 900-980°C, 900-960°C, 900-950°C, 900-930°C, 920-950°C, 910-1000°C, 920-1000°C, 930-1000°C, 940-1000°C, etc. The crystallization treatment time includes 5-1440 min and all ranges and subranges therebetween, such as 5-100 min, 5-150 min, 5-200 min, 50-300 min, 100-440 min, 90-340 min, 200-1240 min, 800-1040 min, 500-740 min, 900-1040 min, 200-340 min, 100-300 min, 500-1440 min, etc.

[0178] In some embodiments, the heating rate during the crystallization process affects the crystal phase composition in the glass-ceramics, and ultimately affects the performance of the glass-ceramic product. Different heating rates can bring different structures and properties to the glass-ceramic product. When the heating rate is kept within the range of 0-20°C / min during the crystallization treatment of the glass precursor prepared according to the present application, impurity crystal phases such as Li-containing crystal phases (β-spodumene, etc.), quartz and quartz solid solutions, etc. are easily precipitated in the glass-ceramics. The inventors have found that in the spinel microcrystal system, the presence of impurity crystal phases such as β-quartz, β-quartz solid solution, β-spodumene, etc. can seriously affect the optical properties of the spinel glass-ceramic material, causing the crystallized glass-ceramic material to appear hazy, even to lose transparency, and causing the transmittance of the prepared glass-ceramic product to decrease significantly. This situation is not desirable for cover glass products. When the heating rate is greater than 20°C / min, preferably greater than or equal to 25°C / min, and more preferably greater than or equal to 30°C / min, the Li ions introduced in the glass component will always remain in the glass phase that is easy to ion exchange, and other impurity crystal phases that affect the optical properties of the glass-ceramic will not precipitate, and will not affect the transmittance of the spinel glass-ceramic. This can be seen in detail in Figure 4 and Figure 5 .

[0179] As can be seen from Figure 4 , when the crystallization treatment is performed, the heating rate is kept within the range of 0-20°C / min, and impurity crystals will precipitate in the glass (there are obvious extra characteristic peaks on the XRD pattern), mainly β-quartz, β-quartz solid solution, β-spodumene, etc. Combined with Figure 5It can be seen that the impurity crystal phases separated from the glass will seriously affect the optical performance of the glass, resulting in glass fogging, and even devitrification. When the crystallization treatment is performed, the heating rate is greater than 20℃ / min, and is 30℃ / min, no impurity crystals are separated, and the glass remains transparent. The heating rate when the crystallization treatment is performed in the present application includes greater than 20℃ / min, less than or equal to 35℃ / min, and all ranges and sub-ranges therebetween, such as 21-30℃ / min, 22-25℃ / min, 25-30℃ / min, 23-28℃ / min, 22-30℃ / min, 23-30℃ / min, 24-30℃ / min, 25-28℃ / min, 21-35℃ / min, etc. In some embodiments, the heating rate when the crystallization treatment is performed can be 21℃ / min, 22℃ / min, 23℃ / min, 24℃ / min, 25℃ / min, 28℃ / min, 30℃ / min, 35℃ / min, etc.

[0180] The heating rate during the nucleation process affects the formation of crystal nuclei, the number of crystal nuclei, and ultimately the crystallinity of the glass-ceramic, and the intrinsic strength of the glass-ceramic. The heating rate when the nucleation treatment is performed in the present application includes 5-20℃ / min and all ranges and sub-ranges therebetween, such as 5-10℃ / min, 10-20℃ / min, 11-20℃ / min, 12-15℃ / min, 9-20℃ / min, 13-20℃ / min, 10-19℃ / min, 9-17℃ / min, etc. In some embodiments, the heating rate when the nucleation treatment is performed can be 5℃ / min, 9℃ / min, 10℃ / min, 11℃ / min, 12℃ / min, 13℃ / min, 15℃ / min, 16℃ / min, 17℃ / min, 19℃ / min, 20℃ / min, etc.

[0181] Thirdly, the present application also provides a strengthened glass-ceramic. The strengthened glass-ceramic of the present application is prepared by chemical strengthening ion exchange of the transparent spinel glass-ceramic described above; the strengthened glass-ceramic has a compressive stress region extending from its surface to a depth of compression. The strengthened glass-ceramic includes a compressive stress layer at the surface and a tensile stress layer at the interior. The compressive stress layer is a compressive stress region formed by chemical strengthening, and the tensile stress layer is a region that has not been ion exchanged. The composition of the tensile stress layer of the strengthened glass-ceramic is the same as that of the transparent spinel glass-ceramic described above.

[0182] In specific implementation, the transparent spinel glass-ceramic described above is subjected to one or more steps of ion exchange in a salt bath, thereby obtaining the strengthened glass-ceramic.

[0183] The transparent spinel glass-ceramics described above can be chemically strengthened. During the chemical strengthening ion exchange process, the glass-ceramics will step or simultaneously exchange K + -Na + , Na + -Li + binary ion exchange, so that the glass-ceramics obtains a compound compressive stress layer after ion exchange, and the strengthened glass-ceramics has a compressive stress region extending from its surface to the compressive depth.

[0184] The transparent spinel glass-ceramics described above can use multiple ion exchange processes to enhance the performance of the glass-ceramics. By using ion exchange salt baths with different ion concentrations, a stress curve is generated at a selected depth, so that the resulting strengthened glass-ceramics has excellent stress performance.

[0185] The strengthened glass-ceramics provided by the present application contains spinel crystals and zirconia crystals in the crystal phase, and does not contain Li-containing crystals, quartz and quartz solid solution; the spinel crystals include zinc spinel and magnesium spinel, and / or a solid solution of zinc spinel (ZnAl2O4) and magnesium spinel (MgAl2O4). The strengthened glass-ceramics exhibits a crystallinity of at least 30.00wt%, and the average size of the crystals in the strengthened glass-ceramics is less than or equal to 15.0nm. The transmittance of the strengthened glass-ceramics at 550nm is greater than 85.00% at a thickness of 0.7mm.

[0186] The compression stress layer depth DOL_0 of the strengthened glass-ceramics of the present application is greater than or equal to 14% of the thickness of the strengthened glass-ceramics. Due to the increase in the content of Li2O and Na2O, there are more Na ions and Li ions available for ion exchange in the glass-ceramics, and a higher compression stress layer depth can be formed.

[0187] When the glass-ceramic has a thickness of 0.7 mm, DOL_0 is greater than or equal to 100.0 pm, including DOL_0 greater than or equal to 100.0 pm and all ranges and sub-ranges therebetween, for example, 100.0-125.0 pm, 100.0-127.0 pm, 100.0-135.0 pm, 100.0-140.0 pm, 100.0-112.0 pm, 100.0-115.0 pm, 100.0-116.0 pm, 100.0-112.0 pm, 104.0-120.0 pm, 106.0-111.0 pm, 108.0-120.0 pm, 104.0-120.0 pm, 108.0-120.0 pm, etc. In some embodiments, DOL_0 can be 100.0 pm, 104.0 pm, 106.0 pm, 108.0 pm, 111.0 pm, 112.0 pm, 115.0 pm, 116.0 pm, 120.0 pm, 125.0 pm, 127.0 pm, 135.0 pm, 140.0 pm, etc.

[0188] The strengthened glass-ceramic of the present disclosure has a tensile stress linear density CT_LD greater than or equal to 25000 MPa / mm, including greater than or equal to 25000 MPa / mm and all ranges and sub-ranges therebetween, for example, 25000-40000 MPa / mm, 27000-40000 MPa / mm, 25000-38000 MPa / mm, 25000-37000 MPa / mm, 25000-39000 MPa / mm, 27000-38000 MPa / mm, 27000-39000 MPa / mm, 28000-38000 MPa / mm, etc. In some embodiments, CT_LD can be 25000 MPa / mm, 27000 MPa / mm, 28000 MPa / mm, 37000 MPa / mm, 38000 MPa / mm, 39000 MPa / mm, 40000 MPa / mm, etc.

[0189] The strengthened glass-ceramics of the present application have a surface compressive stress CS greater than or equal to 650 MPa, including all ranges and sub-ranges therein, such as, for example, greater than or equal to 680 MPa, preferably greater than or equal to 700 MPa, preferably greater than or equal to 750 MPa, preferably greater than or equal to 800 MPa, preferably greater than or equal to 900 MPa, preferably greater than or equal to 1000 MPa, preferably 700 to 800 MPa, preferably 750 to 800 MPa, preferably 760 to 870 MPa, preferably 710 to 860 MPa, preferably 700 to 900 MPa, preferably 800 to 1000 MPa, preferably 850 to 1000 MPa, and the like. In some embodiments, the CS can be 650 MPa, 680 MPa, 700 MPa, 710 MPa, 750 MPa, 760 MPa, 800 MPa, 850 MPa, 860 MPa, 870 MPa, 900 MPa, 1000 MPa, and the like.

[0190] The strengthened glass-ceramics of the present application have an average tensile stress CT AV greater than or equal to 35.0 MPa, including all ranges and sub-ranges therein, such as, for example, greater than or equal to 39.0 MPa, preferably greater than or equal to 40.0 MPa, preferably greater than or equal to 45.0 MPa, preferably greater than or equal to 50.0 MPa, preferably greater than or equal to 55.0 MPa, preferably greater than or equal to 60.0 MPa, preferably greater than or equal to 65.0 MPa, preferably greater than or equal to 70.0 MPa, preferably greater than or equal to 75.0 MPa, preferably 39.0 MPa to 65.0 MPa, preferably 35.0 MPa to 65.0 MPa, preferably 35.0 MPa to 55.0 MPa, preferably 35.0 MPa to 70.0 MPa, and the like. In some embodiments, the CT AV can be 35.0 MPa, 39.0 MPa, 40.0 MPa, 45.0 MPa, 50.0 MPa, 55.0 MPa, 60.0 MPa, 65.0 MPa, 70.0 MPa, 75.0 MPa, and the like.

[0191] The reinforced glass ceramic of the present invention has a Vickers hardness greater than or equal to 740HV0.3, where 740 is the Vickers hardness and 0.3 refers to the load value used for measurement being 0.3 kg. This includes all ranges and sub-ranges greater than or equal to 740HV0.3 and in between, for example, preferably greater than or equal to 760HV0.3, preferably greater than or equal to 770HV0.3, preferably greater than or equal to 780HV0.3, preferably greater than or equal to 790HV0.3, preferably greater than or equal to 800HV0.3, preferably greater than or equal to 820HV0.3, preferably greater than or equal to 830HV0.3, preferably 740HV0.3~780HV0.3, preferably 740HV0.3~830HV0.3, etc. In some implementations, the Vickers hardness can be 740HV0.3, 760HV0.3, 770HV0.3, 780HV0.3, 790HV0.3, 800HV0.3, 820HV0.3, 830HV0.3, etc.

[0192] The fracture toughness of the reinforced glass-ceramic of the present invention is greater than or equal to 1.500 MPa·m. 1 / 2 The fracture toughness of the reinforced glass-ceramic includes a value greater than or equal to 1.500 MPa·m. 1 / 2 and all ranges and subranges thereof, preferably greater than or equal to 1.560 MPa·m 1 / 2 The preferred pressure is 1.500–1.560 MPa·m. 1 / 2 The preferred pressure is 1.600–1.700 MPa·m. 1 / 2 The preferred value is 1.500–1.590 MPa·m. 1 / 2 The preferred value is 1.540–1.600 MPa·m 1 / 2 The preferred value is 1.500–1.610 MPa·m 1 / 2 The preferred value is 1.500–1.630 MPa·m 1 / 2 The preferred value is 1.500–1.700 MPa·m. 1 / 2 In some embodiments, the fracture toughness of the reinforced glass-ceramic can be 1.500 MPa·m. 1 / 2 1.540 MPa·m 1 / 2 1.560 MPa·m 1 / 2 1.590 MPa·m 1 / 2 1.600 MPa·m 1 / 2 1.610 MPa·m 1 / 2 1.630 MPa·m 1 / 2 1.700 MPa·m 1 / 2 wait.

[0193] In the present application, the transparent spinel glass-ceramics, whether one-step ion exchange or multi-step ion exchange is selected, can obtain a strengthened glass-ceramic product with better performance after ion exchange due to the intrinsic strength of the glass-ceramics has been improved.

[0194] The salt bath used in the present application includes at least one of potassium salt and sodium salt. For the salt to be used for ion exchange, nitrate salt is conventional, but any suitable salt or combination of salts can also be used.

[0195] When one-step ion exchange is performed, the salt bath composition includes 50-100wt% NaNO3+0-50wt% KNO3, the ion exchange temperature is 400-500°C, and the ion exchange time is 0.5-48h. The "ion exchange time" here refers to the time for placing the glass-ceramics in the salt bath corresponding to the specified temperature and ratio for chemical strengthening.

[0196] The ion exchange temperature includes 400-500°C and all ranges and sub-ranges therebetween, such as 400-500°C, 400-410°C, 400-420°C, 400-430°C, 400-440°C, 400-450°C, 400-460°C, 400-470°C, 410-450°C, 430-500°C, 440-500°C, etc.; the ion exchange time includes 0.5-48h and all ranges and sub-ranges therebetween, such as 0.5-46h, 1-10h, 1-5h, 1-40h, 7-30h, 9-29h, 10-41h, 6-32h, 9-27h, 4-33h, 5-27h, 6-38h, etc.

[0197] The salt bath composition includes 50-100wt% NaNO3 and all ranges and sub-ranges therebetween, such as 50-60wt%, 50-70wt%, 50-80wt%, 50-90wt%, 60-100wt%, 70-100wt%, 80-100wt%, 50-89wt%, 64-88wt%, 90-100wt%, etc.; and 0-50wt% KNO3 and all ranges and sub-ranges therebetween, such as 0-40wt%, 0-30wt%, 0-20wt%, 0-10wt%, 0-14wt%, 0-15wt%, 0-35wt%, 0-45wt%, 5-40wt%, 20-30wt%, etc.

[0198] When two-step ion exchange is performed, the first step salt bath composition includes 90-100wt% NaNO3+0-10wt% KNO3, the ion exchange temperature is 400-500°C, and the ion exchange time is 0.5-48h;

[0199] The second step salt bath composition includes 0-10wt% NaNO3+90-100wt% KNO3, the ion exchange temperature is 400-500℃, and the ion exchange time is 0.5-48h.

[0200] The ion exchange temperature includes 400-500℃ and all ranges and subranges therebetween, for example, 400-500℃, 400-410℃, 400-420℃, 400-430℃, 400-440℃, 400-450℃, 400-460℃, 400-470℃, 410-450℃, 430-500℃, 440-500℃, etc.; the ion exchange time includes 0.5-48h and all ranges and subranges therebetween, for example, 0.5-46h, 1-10h, 1-5h, 1-40h, 7-30h, 9-29h, 10-41h, 6-32h, 9-27h, 4-33h, 5-27h, 6-38h, etc.

[0201] The first step salt bath composition includes 90-100wt% NaNO3 and all ranges and subranges therebetween, for example, 91-100wt%, 92-100wt%, 93-100wt%, 94-100wt%, 95-100wt%, 96-100wt%, 97-100wt%, 98-100wt%, 99-100wt%, etc.; and also includes 0-10wt% KNO3 and all ranges and subranges therebetween, for example, 0-1wt%, 0-2wt%, 0-3wt%, 0-4wt%, 5-10wt%, 2-10wt%, 6-9wt%, 3-8wt%, 2-9wt%, 1-8wt%, etc.

[0202] The second step salt bath composition includes 0-10wt% NaNO3 and all ranges and subranges therebetween, for example, 0-1wt%, 0-2wt%, 0-3wt%, 0-4wt%, 2-10wt%, 3-5wt%, 5-10wt%, 6-10wt%, 2-7wt%, 3-7wt%, etc.; and also includes 90-100wt% KNO3 and all ranges and subranges therebetween, for example, 91-100wt%, 92-100wt%, 93-100wt%, 94-100wt%, 95-100wt%, 96-100wt%, 97-100wt%, 98-100wt%, etc.

[0203] In order to improve the service life of the salt bath, a salt bath protective agent accounting for 0.1-5wt% of the mass percentage of the salt bath can be added to the salt bath, and the salt bath protective agent includes a salt bath protective agent for passivation, precipitation or absorption of Li +phosphates, silicates, carbonates, etc. can be used to passivate, precipitate, or absorb Li + as a salt bath protectant to avoid the Li + concentration increase in the salt bath from exchange out of the salt bath, which can affect the ion exchange performance that the salt bath can provide and the service life of the salt bath. The salt bath protectant includes 0.1-5.0 wt% and all ranges and subranges therebetween, for example, 0.1-4.0 wt%, 0.1-3.0 wt%, 0.1-2.0 wt%, 0.1-1.0 wt%, 0.2-5.0 wt%, 0.5-5.0 wt%, 4.1-5.0 wt%, 3.1-5.0 wt%, 2.6-4.5 wt%, 0.7-3.5 wt%, 0.8-2.5 wt%, 0.9-1.5 wt%, 0.8-2.5 wt%, etc.

[0204] In a fourth aspect, the present application provides an electronic terminal as an article of manufacture. The electronic terminal as an article of manufacture includes a housing comprising a front surface, a back surface, and side surfaces;

[0205] and an electronic assembly at least partially within the housing, the electronic assembly comprising a display device at or adjacent to the front surface of the housing;

[0206] the front surface and / or the back surface and / or the side surfaces comprise the strengthened glass-ceramic material;

[0207] and a cover article overlying the front surface of the housing or overlying the display device, the cover article comprising the strengthened glass-ceramic material;

[0208] The electronic terminal as an article of manufacture comprises a cell phone, a tablet, a photovoltaic device, or other electronic terminal (such as an electronic watch).

[0209] The transparent spinel glass-ceramic material and the strengthened glass-ceramic material of the present application have excellent properties and can be included / used in other articles, such as watches, transparent armor, missile windows, radomes, substrate materials, new types of lighting, viewing windows for equipment in high temperature, high pressure, and corrosive environments, display protection materials and appearance housing protection materials for portable smart electronic devices (including cell phones, tablets, electronic watches, etc.), architectural articles, transportation articles (such as cars, trains, airplanes, sea-going vessels, etc.), appliance articles, or any article that requires a certain degree of transparency, scratch resistance, impact resistance, wear resistance, or a combination thereof.

[0210] In a fifth aspect, the present application is illustrated by specific examples

[0211] Table 1 is a glass-ceramic recipe for schemes 1-6 of the present application

[0212] Base glass composition (mol%) Scheme 1 Scheme 2 Scheme 3 Scheme 4 Scheme 5 Scheme 6 SiO2 52.03 51.76 51.54 56.74 56.33 56.03 Al2O3 18.60 18.50 18.43 16.50 16.38 16.29 TiO2 0.88 0.88 0.87 1.01 1.00 1.00 Zr02 3.02 3.00 2.99 3.50 3.47 3.46 MgO 7.56 7.52 7.49 6.00 5.96 5.93 ZnO 9.66 9.61 9.57 9.21 9.14 9.10 Na2O 3.31 3.29 3.28 2.41 2.39 2.38 Li2O 3.80 4.30 4.70 3.50 4.20 4.70 BaO 1.14 1.14 1.13 1.13 1.13 1.11

[0213] Table 2 is the glass-ceramic formulations of Examples 7-12 of the present application

[0214] Base glass composition (mol%) Scheme 7 Scheme 8 Scheme 9 Scheme 10 Scheme 11 Scheme 12 SiO2 62.60 62.34 61.88 51.13 50.81 50.49 Al2O3 15.05 14.99 14.88 15.80 15.70 15.60 TiO2 0.32 0.32 0.32 1.22 1.21 1.20 ZrO2 3.02 3.01 2.99 4.07 4.04 4.02 MgO 4.03 4.01 3.98 4.10 4.07 4.05 ZnO 8.13 8.10 8.04 15.20 15.11 15.01 Na2O 3.05 3.03 3.01 3.55 3.54 3.52 Li2O 3.80 4.20 4.90 3.60 4.20 4.80 BaO 0.00 0.00 0.00 1.33 1.32 1.31

[0215] Table 3 is the glass-ceramic formulations of Comparative Examples 13-16 of the present application

[0216]

[0217] Table 4 is the properties of the glass-ceramics and corresponding strengthened glass-ceramics prepared in Examples 1-2 and Comparative Examples 13-16

[0218]

[0219]

[0220] Note: DOL_0 is the depth of compressive stress generated after ion exchange of Li ions in the glass-ceramic with Na ions in the salt bath;

[0221] DOL_2 is the depth of compressive stress generated after ion exchange of Na ions in the glass-ceramic with K ions in the salt bath;

[0222] “450-3H” means ion exchange temperature of 450 °C and ion exchange time of 3 h, and other similar expressions have similar meanings.

[0223] “100% NaNO3” means 100 wt% NaNO3, and other similar expressions have similar meanings.

[0224] Table 5 is the properties of the glass-ceramics and corresponding strengthened glass-ceramics prepared in Examples 3-7

[0225]

[0226]

[0227] Note: DOL_0 is the depth of compressive stress generated after ion exchange of Li ions in the glass-ceramic with Na ions in the salt bath;

[0228] DOL_2 is the depth of compressive stress generated after ion exchange of Na ions in the glass-ceramic with K ions in the salt bath;

[0229] “450-3H” means ion exchange temperature of 450 °C and ion exchange time of 3 h, and other similar expressions have similar meanings.

[0230] "100% NaNO3" means 100 wt% NaNO3, and the meaning of other similar expressions is similar.

[0231] Table 6 is the performance of the glass-ceramics prepared in Examples 8-12 and the corresponding strengthened glass-ceramics

[0232]

[0233]

[0234] Note: DOL_0 is the compressive stress depth generated after the Li ions in the glass-ceramics are exchanged with Na ions in the salt bath;

[0235] DOL_2 is the compressive stress depth generated after the Na ions in the glass-ceramics are exchanged with K ions in the salt bath;

[0236] "450-3H" means the ion exchange temperature is 450°C and the ion exchange time is 3h, and the meaning of other similar expressions is similar.

[0237] "100% NaNO3" means 100 wt% NaNO3, and the meaning of other similar expressions is similar.

[0238] Table 7 is the glass-ceramics prepared in Comparative Examples 1-6

[0239]

[0240] Note: The quartz solid solution precipitated in the above comparative examples is mainly β-quartz solid solution.

[0241] Table 8 is the glass-ceramics prepared in Comparative Examples 7-12

[0242]

[0243] Note: The quartz solid solution precipitated in the above comparative examples is mainly β-quartz solid solution.

[0244] For example 1, according to the formula of scheme 1, the ingredients are mixed for 30 minutes, the total amount of the mixed ingredients is 1000g, after mixing, 5g of clarifying agent (NaCl) is added, and then melted in a platinum-gold crucible at 1650°C for 20 hours, then poured into a forming mold to form, after cooling to 900°C, put into a 600°C annealing furnace for annealing for 6 hours, then cooled to room temperature in the furnace, and the glass precursor is obtained. According to the corresponding process conditions in the above table, the glass precursor is sequentially subjected to nucleation treatment and crystallization treatment, and the glass-ceramic product is prepared. According to the corresponding strengthening process conditions in the above table, the glass-ceramic prepared is chemically strengthened, and the strengthened glass-ceramic product is prepared.

[0245] As can be seen from Tables 1-6, because the content of Li₂O and Na₂O in the glass frits of Comparative Examples 13-16 is lower than that in Examples 1-12, the CT_LD of the glass ceramics prepared from them after strengthening treatment is much lower than that of Examples 1-12, and some even fail to reach 20000 MPa / mm. The drop resistance of the strengthened glass ceramics prepared from the glass ceramics of Examples 1-12 is significantly better than that of Comparative Examples 13-16.

[0246] Ten pieces of each of the reinforced glass-ceramics from Comparative Examples 13 and 15, and Examples 5, 6, 11, and 12 were subjected to whole-machine drop tests. The test results are shown in the figure. Figure 1 .according to Figure 1 It can be seen that Comparative Examples 13 and 15 exhibited poor drop performance, with drop heights concentrated between 0.7 and 1.7 m. Examples 5, 6, 11, and 12, due to their higher Li₂O content in the formulation, showed a significant increase in tensile stress linear density (CT_LD) and stress depth (DOL_0) after strengthening treatment, resulting in a significantly improved drop height. Meanwhile, Examples 12 and 6 showed comparable CT_LD levels, indicating that Example 12, with its higher crystallinity, had a significantly higher drop height; only 2 out of the 10 glass pieces dropped had a drop height below 2 m. This demonstrates that in strengthened glass ceramics, drop height is related to both crystallinity and CT_LD. This invention, by ensuring crystallinity while adding a larger amount of Li₂O, ensures a high CT_LD after strengthening and good drop resistance.

[0247] As can be seen from Tables 7 and 8, the heating rate during the crystallization process has a significant impact on the crystal phase type of glass ceramics. In Comparative Examples 1 to 12, when the crystallization heating rate is less than 20℃ / min, impurity quartz solid solution appears in the crystal phase of the glass ceramic material, and the grain size is significantly larger. Although the crystallinity is improved, the transmittance decreases significantly, and the refractive index cannot even be measured. Such glass ceramics cannot meet the requirements as cover plate materials.

[0248] The glass precursors prepared from the material in Scheme 8 were subjected to different crystallization heating rates (5℃ / min, 20℃ / min, 30℃).

[0249] Microcrystallization was performed at a temperature of ( / min), and the resulting glass-ceramic is shown in the image. Figure 5 The XRD pattern of the prepared glass-ceramic is shown in [reference needed]. Figure 4 The transmittance of the prepared glass-ceramic to 550nm wavelength light is shown in the figure. Figure 6 .pass Figures 4-6It can be seen that when the crystallization treatment, the heating rate is 0~20℃ / min range, there will be impurity crystals in the glass (XRD pattern on the emergence of obvious extra characteristic peak), glass-ceramics will fog, even lost transparency. And when the crystallization treatment, the heating rate is 30℃ / min, there is no impurity crystal precipitation, the glass remains transparent state.

[0250] The components of the spinel glass-ceramic material are optimized in the application, more Li ions and Na ions for chemical strengthening ion exchange are introduced into the spinel glass-ceramic, the spinel glass-ceramic without impurity crystal phase (such as Li-containing crystal phase, quartz, quartz solid solution and other impurity crystal phases) is obtained, the glass-ceramic does not appear fogging and loss of transparency and other phenomena, and the glass-ceramic material has excellent transmittance.

[0251] By introducing more Li ions and Na ions into the components of the spinel glass-ceramic, the prepared spinel glass-ceramic can be chemically strengthened, and the transparent strengthened glass-ceramic with high CS, DOL_0, CT_AV and CT_LD is obtained, and the strengthened glass-ceramic shows excellent drop performance.

[0252] After performance testing of the glass-ceramic material prepared in the application, it is found that the transparent spinel glass-ceramic material has high crystallinity, which brings excellent mechanical properties to the glass-ceramic material.

[0253] The application also provides a preparation method of the spinel glass-ceramic, the process method provided in the application controls the process parameters of the crystallization process and the nucleation process, and sets the heating rate parameter requirement, finally the spinel glass-ceramic without impurity crystal phase (such as Li-containing crystal phase, quartz, quartz solid solution and other impurity crystal phases) is obtained, and the glass-ceramic material has excellent optical performance.

[0254] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the application and not to limit the technical solutions, and those of ordinary skill in the art should understand that those who modify or equivalently replace the technical solutions of the application without departing from the purpose and scope of the technical solutions should be covered in the scope of the claims of the application.

Claims

1. A transparent reinforced glass-ceramic with high stress depth, characterized in that, The crystal phase of the reinforced glass ceramic contains spinel crystals and zirconium oxide crystals, but does not contain Li-containing crystals; The reinforced glass ceramic has a compressive stress region extending from its surface to the compressive depth, the compressive stress layer depth DOL_0 is greater than or equal to 14% of the thickness of the reinforced glass ceramic, and the tensile stress linear density CT_LD of the reinforced glass ceramic is 25000~40000MPa / mm. The reinforced glass-ceramic comprises a compressive stress layer on the surface and a tensile stress layer on the interior. The tensile stress layer of the reinforced glass-ceramic, in molar percentage of oxides, comprises: Li₂O: 3.50~6.00 mol% Na₂O: 2.00~4.00 mol% SiO2: 50.00~65.00 mol% Al2O3: 14.50~25.00 mol% MgO: 3.50~8.00 mol% ZnO: 8.00~16.00 mol% BaO: 0~2.00 mol% TiO2+ZrO2: 3.00~5.50 mol% The composition of the reinforced glass-ceramic tensile stress layer, by molar percentage of oxides, is as follows: 0.40≤(Al2O3+ZnO+MgO+ZrO2+TiO2) / (Li2O+Na2O+SiO2+BaO)≤0.

70.

2. The transparent reinforced glass-ceramic with high stress depth according to claim 1, characterized in that, The crystalline phase of the reinforced glass ceramic does not contain quartz or quartz solid solution.

3. The transparent reinforced glass-ceramic with high stress depth according to claim 1, characterized in that, The tensile stress linear density CT_LD of the reinforced glass ceramic is 27000~40000MPa / mm.

4. The transparent reinforced glass-ceramic with high stress depth according to claim 1, characterized in that, The surface compressive stress CS of the reinforced glass ceramic is greater than or equal to 650 MPa.

5. The transparent reinforced glass-ceramic with high stress depth according to claim 4, characterized in that, The surface compressive stress CS of the reinforced glass ceramic is greater than or equal to 680 MPa.

6. The transparent reinforced glass-ceramic with high stress depth according to claim 4, characterized in that, The surface compressive stress CS of the reinforced glass ceramic is 650MPa~1000MPa.

7. The transparent reinforced glass-ceramic with high stress depth according to claim 1, characterized in that, The average tensile stress CT_AV of the reinforced glass ceramic is greater than or equal to 35.0 MPa.

8. The transparent reinforced glass-ceramic with high stress depth according to claim 7, characterized in that, The average tensile stress CT_AV of the reinforced glass ceramic is greater than or equal to 39.0 MPa.

9. The transparent reinforced glass-ceramic with high stress depth according to claim 7, characterized in that, The average tensile stress CT_AV of the reinforced glass ceramic is 35.0 MPa to 70.0 MPa.

10. The transparent reinforced glass-ceramic with high stress depth according to claim 1, characterized in that, The Vickers hardness of the reinforced glass ceramic is greater than or equal to 740HV0.

3.

11. The transparent reinforced glass-ceramic with high stress depth according to claim 1, characterized in that, The fracture toughness of the reinforced glass-ceramic is greater than or equal to 1.500 MPa·m. 1 / 2 .

12. The transparent reinforced glass-ceramic with high stress depth according to claim 11, characterized in that, The fracture toughness of the reinforced glass-ceramic is greater than or equal to 1.560 MPa·m. 1 / 2 .

13. The transparent reinforced glass-ceramic with high stress depth according to claim 11, characterized in that, The fracture toughness of the reinforced glass-ceramic is 1.500–1.700 MPa·m. 1 / 2 .

14. The transparent reinforced glass-ceramic with high stress depth according to claim 1, characterized in that, The spinel crystals include zinc spinel and magnesium spinel.

15. The transparent reinforced glass-ceramic with high stress depth according to claim 1, characterized in that, At a thickness of 0.7 mm, the reinforced glass ceramic has a transmittance of greater than 85.00% at 550 nm.

16. The transparent reinforced glass-ceramic with high stress depth according to claim 1, characterized in that, The reinforced glass-ceramic exhibits a crystallinity of at least 30.00 wt%.

17. The transparent reinforced glass-ceramic with high stress depth according to claim 1, characterized in that, The average crystal size in the reinforced glass ceramic is less than or equal to 15.0 nm.

18. The transparent reinforced glass-ceramic with high stress depth according to claim 1, characterized in that, The composition of the reinforced glass-ceramic tensile stress layer, by molar percentage of oxides, is as follows: 0.43≤(Al2O3+ZnO+MgO+ZrO2+TiO2) / (Li2O+Na2O+SiO2+BaO)≤0.

68.

19. The transparent reinforced glass-ceramic with high stress depth according to claim 1, characterized in that, The composition of the reinforced glass-ceramic tensile stress layer, by molar percentage of oxides, is as follows: Na2O / (Li2O+Na2O+SiO2+BaO)≥0.035; and / or Li2O / (Li2O+Na2O+SiO2+BaO)≥0.

054.

20. The transparent reinforced glass-ceramic with high stress depth according to claim 19, characterized in that, The composition of the reinforced glass-ceramic tensile stress layer, by molar percentage of oxides, is as follows: 0.035≤Na2O / (Li2O+Na2O+SiO2+BaO) ≤0.070; and / or 0.054≤Li2O / (Li2O+Na2O+SiO2+BaO) ≤0.

090.

21. The transparent reinforced glass-ceramic with high stress depth according to claim 1, characterized in that, The composition of the reinforced glass-ceramic tensile stress layer, in terms of the molar percentage of oxides, includes: SiO2: 50.00~63.00 mol%; and / or Al2O3: 14.50~20.00 mol%; and / or MgO: 3.90~7.60 mol%; and / or ZnO: 8.00~15.50 mol%; and / or BaO: 0~1.50 mol%; and / or Li₂O: 3.50~5.00 mol%; and / or Na₂O: 2.30~3.60 mol%; and / or TiO2: 0~2.00 mol%; and / or ZrO2: 2.50~5.00 mol%.

22. The transparent reinforced glass-ceramic with high stress depth according to claim 1, characterized in that, The composition of the reinforced glass-ceramic tensile stress layer, in terms of the molar percentage of oxides, includes: SiO2: 50.00~57.00 mol%; and / or Al2O3: 15.00~19.00 mol%; and / or MgO: 4.00~7.50 mol%; and / or ZnO: 9.00~15.20 mol%; and / or BaO: 1.00~1.35 mol%; and / or Li₂O: 4.00~5.00 mol%; and / or Na₂O: 3.00~3.60 mol%; and / or TiO2: 0.30~1.30 mol%; and / or ZrO2: 2.90~4.20 mol%.

23. The transparent reinforced glass-ceramic with high stress depth according to claim 16, characterized in that, The reinforced glass-ceramic exhibits a crystallinity of 30.00–50.00 wt%.

24. A method for preparing transparent reinforced glass-ceramics with high stress depth, characterized in that: Includes the following steps: (1) Mix the ingredients according to the formula to prepare the glass precursor; (2) The obtained glass precursor is subjected to nucleation and crystallization treatments in sequence to prepare transparent spinel glass ceramics; (3) The transparent spinel glass ceramic obtained in step (2) is subjected to one or more steps of ion exchange in a salt bath to obtain the reinforced glass ceramic as described in any one of claims 1-23; In step (2), during the crystallization process, the temperature is increased to the crystallization temperature at a rate greater than 20°C / min.

25. The preparation method according to claim 24, characterized in that: In step (2): During nucleation, the nucleation temperature is 700–800℃ and the nucleation time is 30–1440 min. When performing crystallization treatment, the crystallization temperature is 900-1000℃ and the crystallization time is 5-1440 min.

26. The preparation method according to claim 24, characterized in that: In step (2), during the nucleation process, the temperature is increased to the nucleation temperature at a rate of 5 to 20 °C / min.

27. The preparation method according to claim 24, characterized in that: In step (3), when performing one-step ion exchange, the salt bath composition includes: 50~100wt% NaNO3 + 0~50wt% KNO3, the ion exchange temperature is 400~500℃, and the ion exchange time is 0.5~48 h.

28. The preparation method according to claim 24, characterized in that: In step (3), during the two-step ion exchange, The first step involves a salt bath consisting of 90-100 wt% NaNO3 + 0-10 wt% KNO3, with an ion exchange temperature of 400-500℃ and an ion exchange time of 0.5-48 h. The second step involves a salt bath consisting of 0-10 wt% NaNO3 and 90-100 wt% KNO3. The ion exchange temperature is 400-500℃, and the ion exchange time is 0.5-48 h.

29. The preparation method according to claim 24, characterized in that: In step (2): In step (2), during the crystallization process, the temperature is increased to the crystallization temperature at a heating rate greater than or equal to 25°C / min.

30. The preparation method according to claim 29, characterized in that: In step (2): In step (2), during the crystallization process, the temperature is increased to the crystallization temperature at a heating rate greater than or equal to 30°C / min.

31. The application of the reinforced glass ceramic according to any one of claims 1-23 in watches, transparent armor, missile windows, fairings, substrate materials, new lamps, observation windows of equipment in high temperature, high pressure and corrosive environments, automobiles, trains, airplanes, marine vehicles, building materials and portable intelligent electronic devices.

32. An electronic terminal, characterized in that, include: The housing includes a front surface, a rear surface, and side surfaces; And some electronic components located within the housing, the electronic components including a display device located on or adjacent to the front surface of the housing; The front surface and / or rear surface and / or side surface comprise the reinforced glass-ceramic material as described in any one of claims 1-23; It also includes a cover article covering the front surface of the housing or located on the display device, the cover article comprising the reinforced glass-ceramic material as described in any one of claims 1-23; the electronic terminal includes a mobile phone, a tablet computer, a photovoltaic device, or other electronic terminal.

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