A strengthened glass ceramic, cover glass, electronic device, and glass article

Abstract

The application provides a kind of spinel-containing strengthened glass ceramic, cover glass, electronic device and glass device, belongs to the technical field of glass-ceramics.The zinc-aluminum spinel-magnesium-aluminum spinel solid solution is used as the main crystal phase of the glass ceramic, so that the glass ceramic obtains high intrinsic strength, and the surface composition and stress distribution of the prepared strengthened glass ceramic meet specific requirements by chemical strengthening, especially the surface Na2O content, surface K2O content, K + diffusion depth, Na + concentration maximum position depth meet specific requirements, while the thickness, K + diffusion depth (or K + exchange (layer) depth) DOL_K, |CT-AV| and compressive stress layer depth DOL_0 of the strengthened glass ceramic meet formula A, which significantly improves the mechanical properties of the strengthened glass ceramic, so that the strengthened glass ceramic simultaneously obtains excellent extrusion resistance and impact resistance.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of microcrystalline glass, in particular to a strengthened glass ceramic, a cover glass, an electronic device and a glass device. BACKGROUND

[0002] In recent years, glass ceramics are often used in many electronic devices, such as smart phones, smart wear, computers, tablets, cameras, electronic watches, smart detection devices and other similar devices, as window glass, protective cover glass, etc. The damage risk points encountered by electronic devices applied in different scenarios are not completely the same. For example, as a smart phone, tablet, etc., the damage risks encountered mainly include scratching, dropping and impact problems, and in deep-sea detection environment, diving environment, etc., the electronic devices used encounter not only impact problems but also water pressure extrusion problems. In order to better meet the application requirements of electronic devices in different application scenarios and achieve better protection of electronic devices, it is necessary to develop glass ceramic materials that can exhibit higher performance. However, the extrusion resistance and impact resistance of the existing glass ceramics still need to be further improved. SUMMARY

[0003] 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 and impact resistance compared to ordinary glass.

[0004] The purpose of the present application is to provide a strengthened glass ceramic with spinel crystal phase as the main crystal phase, which has excellent impact resistance and excellent extrusion resistance.

[0005] To achieve the above purpose, the present application provides the following technical solutions:

[0006] In a first aspect, a strengthened glass ceramic is provided, wherein the strengthened glass ceramic comprises a main crystal phase of zinc aluminate spinel-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.

[0007] In terms of mass percentage of oxides, the mass percentage of K2O on the surface of the strengthened glass ceramic is 2.50% to 7.50%, preferably the mass percentage of K2O on the surface of the strengthened glass ceramic is 3.00% to 7.00%, and more preferably the mass percentage of K2O on the surface of the strengthened glass ceramic is 3.50% to 7.00%;

[0008] The surface Na2O mass percentage of the strengthened glass ceramic is less than or equal to 0.010% in terms of the mass percentage of oxides, 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%;

[0009] The strengthened glass ceramic satisfies: 8.00 μm≤DOL_K≤20.00 μm, preferably, 8.50 μm≤DOL_K≤18.00 μm, more preferably, 9.00 μm≤DOL_K≤16.00 μm, wherein DOL_K is the K + diffusion depth;

[0010] The strengthened glass ceramic satisfies: 30.00 μm≤DOL_Na≤60.00 μm, preferably, 34.00 μm≤DOL_Na≤59.00 μm, more preferably, 37.00 μm≤DOL_Na≤59.00 μm, wherein DOL_Na is the Na + depth of the position of the maximum concentration;

[0011] The strengthened glass ceramic satisfies: A=(t×DOL_K) / (|CT-AV|×(DOL_0 / t)), 850≤A≤4000, preferably, 850≤A≤3000, more preferably, 900≤A≤2000; wherein t is the thickness of the strengthened glass ceramic, in units of μm; DOL_K is the K + diffusion depth, in units of μm; |CT-AV| is the absolute value of the average tensile stress of the strengthened glass ceramic, in units of MPa; DOL_0 is the depth of the compressive stress layer of the strengthened glass ceramic, in units of μm; in the formula A, the data is substituted into the formula according to the above unit requirements, and the calculation result is obtained, and the unit does not participate in the calculation.

[0012] The present application obtains high intrinsic strength of the glass ceramic by taking the zinc aluminate-magnesium aluminate spinel solid solution as the main crystal phase of the glass ceramic, and the surface composition and stress distribution of the prepared strengthened glass ceramic satisfy specific requirements by chemical strengthening of the glass ceramic, especially the surface Na2O content, surface K2O content, K + diffusion depth, Na + depth of the position of the maximum concentration satisfy specific requirements, and the thickness, K + diffusion depth (or K +The DOL_K, |CT-AV| and DOL_0 satisfy the requirement of formula A, which significantly improves the mechanical properties of the strengthened glass ceramic, and the strengthened glass ceramic simultaneously obtains excellent extrusion resistance and impact resistance. In the present application, (Zn, Mg)Al2O4 represents a zinc aluminate-magnesium aluminate solid solution (or also referred to as a zinc magnesium spinel solid solution, a zinc spinel-magnesium spinel solid solution, a zinc magnesium aluminate spinel solid solution).

[0013] As an optional embodiment, the surface K2O mass percentage of the strengthened glass ceramic is 5.62%, 4.66%, 6.78%, 4.95%, 3.86%, 4.96%, 4.55%, 4.53%, 4.04%, 5.73%, 5.39%, 6.11% or 5.89%; and / or,

[0014] The surface Na2O mass percentage of the strengthened glass ceramic is 0% or 0.002%; and / or,

[0015] The DOL_K of the strengthened glass ceramic is 12.10 μm, 11.00 μm, 9.40 μm, 15.10 μm, 14.10 μm, 13.00 μm, 11.10 μm, 19.10 μm, 18.00 μm or 17.10 μm; and / or,

[0016] The DOL_Na of the strengthened glass ceramic is 46.10 μm, 40.00 μm, 55.10 μm, 45.40 μm, 47.10 μm, 58.10 μm, 48.00 μm, 51.10 μm, 38.00 μm, 43.10 μm, 50.30 μm, 50.20 μm or 56.40 μm; and / or,

[0017] The value of formula A is 1039, 1150, 1520, 910, 1542, 1469, 935, 995, 1780, 1054, 1500, 2010 or 2440.

[0018] As an optional embodiment, the strengthened glass ceramic satisfies: along the thickness direction of the strengthened glass ceramic, the concentration of K + shows a nonlinear decreasing trend from the main surface of the strengthened glass ceramic to the center of the strengthened glass ceramic; and / or,

[0019] Along the thickness direction of the strengthened glass ceramic, the concentration of Na + shows a nonlinear increasing trend first, and then a nonlinear decreasing trend from the main surface of the strengthened glass ceramic to the center of the strengthened glass ceramic.

[0020] As an optional embodiment, the strengthened glass ceramic satisfies:

[0021] In a K element concentration distribution curve with the horizontal axis being depth in μm from the main surface of the strengthened glass ceramic and the vertical axis being K element concentration in mass percent on an elemental basis:

[0022] The absolute value P1 of the average slope of the K element concentration distribution curve between the depth of 0 μm and the depth of DOL_K is 0.150-1.000, preferably, P1 is 0.150-0.800, more preferably, P1 is 0.150-0.600; and / or,

[0023] The absolute value P2 of the average slope of the K element concentration distribution curve between the depth of 5 μm and the depth of 8 μm is 0.50-2.50, preferably, P2 is 0.60-2.00, more preferably, P2 is 0.70-1.50; and / or, 5-8 5-8 5-8

[0024] In a Na element concentration distribution curve with the horizontal axis being depth in μm from the main surface of the strengthened glass ceramic and the vertical axis being Na element concentration in mass percent on an elemental basis:

[0025] The absolute value P2 of the average slope of the Na element concentration distribution curve between the depth of 0 μm and the depth of DOL_Na is 0.01-0.05, preferably, P2 is 0.01-0.04, more preferably, P2 is 0.01-0.03.

[0026] In the present application, by making the average slope of the K element concentration distribution curve and / or the Na element concentration distribution curve in different depth ranges of the strengthened glass ceramic satisfy specific requirements, it is beneficial to make the strengthened glass ceramic achieve a desired stress distribution structure, and further beneficial to make the strengthened glass ceramic simultaneously obtain excellent impact resistance and extrusion resistance.

[0027] As an optional embodiment, the strengthened glass ceramic satisfies:

[0028] In a K element concentration distribution curve with the horizontal axis being depth in μm from the main surface of the strengthened glass ceramic and the vertical axis being K element concentration in mass percent on an elemental basis:

[0029] ​​​The absolute value P1 of the average slope of the K element concentration distribution curve between the depth of 0 microns and the depth of DOL_K is 0.380, 0.315, 0.302, 0.530, 0.348, 0.193, 0.445, 0.452, 0.194, 0.440, 0.220, or 0.310; and / or,

[0030] The absolute value P2 of the average slope of the Na element concentration distribution curve between the depth of 0 microns and the depth of DOL_Na is 0.02, 0.01, or 0.03. 5-8 The absolute value P1 of the average slope of the K element concentration distribution curve between the depth of 0 microns and the depth of DOL_K is 0.74, 1.12, 1.22, 0.99, 1.04, 1.25, 0.76, 0.80, 0.79, 0.95, 0.66, 1.34, or 1.64; and / or

[0031] In a Na element concentration distribution curve with the horizontal axis being the depth in microns from the main surface of the strengthened glass ceramic and the vertical axis being the Na element concentration in mass percent on an element basis:

[0032] The absolute value P2 of the average slope of the Na element concentration distribution curve between the depth of 0 microns and the depth of DOL_Na is 0.02, 0.01, or 0.03.

[0033] As an optional embodiment, the strengthened glass ceramic satisfies:

[0034] In an SLP stress distribution curve with the horizontal axis being the depth in microns from the main surface of the strengthened glass ceramic and the vertical axis being the stress in MPa:

[0035] The absolute value K of the average slope of the SLP stress distribution curve between the depth of 50 microns and the depth of 80 microns is 1.00-2.50, preferably, K is 1.00-2.40, more preferably, K is 1.00-2.30; and / or, 50-80 The absolute value K of the average slope of the SLP stress distribution curve between the depth of 50 microns and the depth of 80 microns is 1.00-2.50, preferably, K is 1.00-2.40, more preferably, K is 1.00-2.30; and / or, 50-80 The absolute value K of the average slope of the SLP stress distribution curve between the depth of 50 microns and the depth of 80 microns is 1.00-2.50, preferably, K is 1.00-2.40, more preferably, K is 1.00-2.30; and / or, 50-80 The absolute value K of the average slope of the SLP stress distribution curve between the depth of 50 microns and the depth of 80 microns is 1.00-2.50, preferably, K is 1.00-2.40, more preferably, K is 1.00-2.30; and / or,

[0036] The absolute value K of the average slope of the SLP stress distribution curve between the depth of 80 microns and the depth of DOL_0 is 0.90-2.00, preferably, K is 0.90-1.80, more preferably, K is 0.90-1.60. 80DOL-0 The absolute value K of the average slope of the SLP stress distribution curve between the depth of 80 microns and the depth of DOL_0 is 0.90-2.00, preferably, K is 0.90-1.80, more preferably, K is 0.90-1.60. 80DOL-0 The absolute value K of the average slope of the SLP stress distribution curve between the depth of 80 microns and the depth of DOL_0 is 0.90-2.00, preferably, K is 0.90-1.80, more preferably, K is 0.90-1.60. 80 DOL-0 The absolute value K of the average slope of the SLP stress distribution curve between the depth of 80 microns and the depth of DOL_0 is 0.90-2.00, preferably, K is 0.90-1.80, more preferably, K is 0.90-1.60.

[0037] In the present application, by making the average slopes of the stress distribution curves of the strengthened glass ceramic in different depth ranges satisfy certain requirements, it is beneficial to make the strengthened glass ceramic achieve a desired stress distribution structure, and thus it is beneficial for the strengthened glass ceramic to simultaneously have excellent impact resistance and extrusion resistance.

[0038] As an optional embodiment, the strengthened glass ceramic satisfies:

[0039] In an SLP stress profile curve with the horizontal axis being the depth in μm from the main surface of the strengthened glass ceramic, and the vertical axis being the stress in MPa:

[0040] The absolute value K of the average slope of the SLP stress profile curve between the depth of 50 μm and the depth of 80 μm 50-80 is 1.92, 1.48, 1.52, 1.38, 1.70, 1.03, 1.59, 1.28, 2.29, 1.50, 1.56 or 1.73; and / or,

[0041] The absolute value K of the average slope of the SLP stress profile curve between the depth of 80 μm and the depth of DOL_0 80DOL-0 is 1.35, 1.06, 1.05, 1.33, 1.17, 0.98, 1.29, 1.09, 1.42, 1.18 or 1.13.

[0042] As an optional embodiment, the strengthened glass ceramic is in a plate shape, 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 0.9 mm to 2.0 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 and impact resistance of the strengthened glass ceramic will be obviously reduced, and when the thickness is too large, on the one hand, the weight will be increased, which is not conducive to the light and thin electronic device, and on the other hand, the transmittance of the glass ceramic will be reduced, and the transmittance performance will be poor.

[0043] As an optional embodiment, the composition at the center of the strengthened glass ceramic contains Al2O3 with a mass percentage greater than or equal to 30.00% in terms of mass percentage of oxides.

[0044] 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 ensured, so that the glass-ceramic has high intrinsic strength (or also known as inherent strength), and on the other hand, a certain amount of alumina is also 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 to form a unified grid with [SiO4], so that the degree of network connection 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 the strengthened glass-ceramic with excellent mechanical strength performance.

[0045] As an optional embodiment, in the composition at the center of the strengthened glass-ceramic, the mass percentage of ZrO2 is greater than or equal to 3.00% in terms of mass percentage of oxides.

[0046] In the present application, by controlling the mass percentage of ZrO2 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, ZrO2 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, ZrO2 exists in the glass phase in the form of [ZrO8] cube, which can enhance the interionic interaction and make the glass structure more compact, thereby being conducive to improving the mechanical strength of the glass phase. At the same time, ZrO2 can significantly improve the surface compressive stress formed by ion exchange, thereby improving the surface stress level of the strengthened glass-ceramic obtained thereby.

[0047] As an optional embodiment, in the composition at the center of the strengthened glass-ceramic, 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, and more preferably 1.00-3.00; and / or

[0048] In the composition at the center of the strengthened glass-ceramic, 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, and more preferably 0.04-0.10.

[0049] 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 beneficial to obtain a strengthened glass ceramic with excellent mechanical strength performance.

[0050] As an optional embodiment, the composition at the center of the strengthened glass ceramic, in terms of mass percentage of oxides, comprises: 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%.

[0051] In the present application, by adjusting and controlling the content range of each oxide component, it is beneficial to ensure that the strengthened glass ceramic meets the desired crystal structure and stress structure, and at the same time, it is beneficial to ensure that the strengthened glass ceramic has excellent optical performance and high intrinsic strength.

[0052] As an optional embodiment, the composition at the center of the strengthened glass ceramic, in terms of mass percentage of oxides, comprises:

[0053] The mass percentage of SiO2 is 30.00% to 42.00%, preferably, the mass percentage of SiO2 is 35.00% to 40.00%; and / or,

[0054] The mass percentage of Al2O3 is 32.00% to 42.00%, preferably, the mass percentage of Al2O3 is 34.00% to 42.00%; and / or,

[0055] The mass percentage of ZrO2 is 4.00% to 7.00%, preferably, the mass percentage of ZrO2 is 5.00% to 6.00%; and / or,

[0056] The mass percentage of MgO is 2.50% to 4.00%, preferably, the mass percentage of MgO is 2.50% to 3.50%; and / or,

[0057] The mass percentage of ZnO is 9.00% to 13.00%, preferably, the mass percentage of ZnO is 9.00% to 11.00%; and / or,

[0058] Na2O in a mass percent of 1.00% to 8.00%, preferably in a mass percent of 2.00% to 6.00%; and / or,

[0059] K2O in a mass percent of 0% to 3.00%, preferably in a mass percent of 0% to 1.00%; and / or,

[0060] Li2O in a mass percent of 1.00% to 4.00%, preferably in a mass percent of 2.00% to 3.00%; and / or,

[0061] CaO in a mass percent of 0% to 3.00%, preferably in a mass percent of 0% to 1.50%; and / or,

[0062] B2O3 in a mass percent of 0% to 8.00%, preferably in a mass percent of 0% to 4.00%; and / or,

[0063] BaO in a mass percent of 0% to 7.00%, preferably in a mass percent of 0% to 4.00%; and / or,

[0064] Y2O3 in a mass percent of 0% to 4.00%, preferably in a mass percent of 0% to 2.00%; and / or,

[0065] La2O3 in a mass percent of 0% to 5.00%, preferably in a mass percent of 0% to 3.00%.

[0066] As an optional embodiment, the composition at the center of the strengthened glass ceramic comprises, in mass percent of oxides:

[0067] SiO2 in a mass percent of 37.08%, 36.87%, 33.23%, 37.43%, 37.40%, 38.33%, 36.05%, 35.67%, or 32.39%; and / or,

[0068] Al2O3 in a mass percent of 35.83%, 36.98%, 36.27%, 37.52%, 36.60%, 37.07%, 34.84%, 34.55%, or 35.88%; and / or,

[0069] the mass percent of Zr02 is 5.69%, 5.65%, 5.61%, 5.74%, 5.81%, 5.89%, 5.54%, or 5.48%; and / or, the mass percent of MgO is 3.00%, 2.98%, 3.04%, 3.03%, 3.06%, 3.10%, 2.92%, or 2.89%; and / or,

[0070] the mass percent of ZnO is 10.77%, 10.71%, 10.55%, 10.87%, 11.01%, 11.15%, 10.46%, or 10.37%; and / or,

[0071] the mass percent of Na20 is 2.86%, 2.85%, 2.89%, 3.00%, 1.69%, 2.79%, or 2.76%; and / or,

[0072] preferably free of K20; and / or,

[0073] the mass percent of Li20 is 2.35%, 1.55%, 1.50%, 1.77%, 1.60%, 1.62%, 2.28%, 2.27%, or 2.24%; and / or,

[0074] the mass percent of CaO is 0%, 0.75%, 1.15%, or 0.92%; and / or,

[0075] the mass percent of B203 is 0% or 7.07%; and / or,

[0076] the mass percent of BaO is 2.42%, 2.41%, 6.94%, 0%, 2.35%, or 2.32%; and / or,

[0077] the mass percent of Y203 is 0%, 1.52%, or 0.60%; and / or,

[0078] the mass percent of La203 is 0%, 2.17%, or 3.69%.

[0079] As an optional embodiment, in the strengthened glass ceramic, the average crystal size is no 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

[0080] in the strengthened glass ceramic, the total content of the crystalline phase is 25% to 60%, preferably 30% to 55%, more preferably 40% to 50%, in terms of mass percent.

[0081] In the present application, by making the glass-ceramics meet the desired total content of crystalline phase / crystallinity, appropriate average crystal size, it is beneficial to make the glass-ceramics maintain excellent optical performance while meeting excellent mechanical strength performance and high intrinsic strength.

[0082] As an optional embodiment, the average crystal size in the strengthened glass-ceramics is 5.0 nm, 6.8 nm, 6.4 nm, 6.5 nm, 8.1 nm or 7.0 nm; and / or

[0083] The total content of crystalline phase in the strengthened glass-ceramics is 48.69%, 45.11%, 49.52%, 47.85%, 54.07%, 51.56%, 45.49% or 44.77% in mass percentage.

[0084] As an optional embodiment, the strengthened glass-ceramics is transparent in the visible light wavelength range, preferably, the transmittance of the strengthened glass-ceramics is ≥85.00% for 550 nm wavelength light at a thickness of 0.90 mm, preferably the transmittance is ≥87.00%. The strengthened glass-ceramics meeting this transmittance can ensure better light transmittance, better transparent effect, and is suitable for use in electronic device display screens which have requirements for display effect.

[0085] As an optional embodiment, the Vickers hardness of the strengthened glass-ceramics is greater than or equal to 750 kgf / mm 2 , preferably the Vickers hardness of the strengthened glass-ceramics is greater than or equal to 790 kgf / mm 2 ; and / or,

[0086] The fracture toughness value of the strengthened glass-ceramics is greater than or equal to 1.00 MPa·m 0.5 , preferably the fracture toughness value of the strengthened glass-ceramics is greater than or equal to 1.20 MPa·m 0.5 , more preferably the fracture toughness value of the strengthened glass-ceramics is greater than or equal to 1.50 MPa·m 0.5 ; and / or,

[0087] The strengthened glass-ceramics has a |CT_AV| greater than 20.00 MPa, |CT_AV| is the absolute value of average tensile stress, preferably the strengthened glass-ceramics has a |CT_AV| of 30.00 MPa to 55.00 MPa; and / or,

[0088] The strengthened glass-ceramics has a |CT_CV| greater than 25.00 MPa, |CT_CV| is the absolute value of maximum tensile stress, preferably the chemical strengthened microcrystalline glass has a |CT_CV| of 40.00 MPa to 75.00 MPa; and / or,

[0089] The strengthened glass ceramic has a CS_50 of greater than 100 MPa, the CS_50 being a compressive stress value at a depth of 50 μm from a main surface of the strengthened glass ceramic, preferably, the strengthened glass ceramic has a CS_50 of 140 MPa to 200 MPa; and / or,

[0090] The strengthened glass ceramic has a CS_80 of greater than 50 MPa, the CS_80 being a compressive stress value at a depth of 80 μm from a main surface of the strengthened glass ceramic, preferably, the strengthened glass ceramic has a CS_80 of 100 MPa to 150 MPa; and / or,

[0091] The strengthened glass ceramic has a DOL_0 of greater than 144 μm, the DOL_0 being a depth of compressive stress layer, preferably, the strengthened glass ceramic has a DOL_0 of 160 μm to 200 μm; and / or,

[0092] The strengthened glass ceramic satisfies: DOL_0 > 0.16t, wherein the DOL_0 is a depth of compressive stress layer, and t is a thickness of the strengthened glass ceramic, preferably, DOL_0 > 0.18t, more preferably, DOL_0 ≥ 0.20t.

[0093] In the present application, 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 and impact resistance of the strengthened glass ceramic. And 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 performance, especially the excellent compression resistance and excellent impact resistance.

[0094] As an optional embodiment, the Vickers hardness of the strengthened glass ceramic is 858 kgf / mm 2 , 875 kgf / mm 2 , 915 kgf / mm 2 , 850 kgf / mm 2 , 837 kgf / mm 2 , 900 kgf / mm 2 , 869 kgf / mm 2 , 889 kgf / mm 2 , 857 kgf / mm 2 , 865 kgf / mm 2 , or 825 kgf / mm 2 ; and / or,

[0095] The fracture toughness value of the strengthened glass ceramic is 1.67 MPa·m 0.5 , 1.69 MPa·m0.5 1.75 MPa-m 0.5 1.65 MPa-m 0.5 1.94 MPa-m 0.5 1.73 MPa-m 0.5 1.68 MPa-m 0.5 1.71 MPa-m 0.5 or 1.77 MPa-m 0.5 ; and / or,

[0096] |CT AV| of the strengthened glass ceramic is 50.96 MPa, 41.74 MPa, 36.56 MPa, 45.01 MPa, 41.49 MPa, 40.48 MPa, 50.27 MPa, 49.49 MPa, 36.05 MPa, 45.43 MPa, 53.86 MPa, 40.86 MPa, or 35.91 MPa; and / or,

[0097] |CT CV| of the strengthened glass ceramic is 65.70 MPa, 54.30 MPa, 46.07 MPa, 68.75 MPa, 53.70 MPa, 53.07 MPa, 66.96 MPa, 71.25 MPa, 42.73 MPa, 60.57 MPa, 81.79 MPa, 52.40 MPa, or 44.78 MPa; and / or,

[0098] CS_50 of the strengthened glass ceramic is 199.69 MPa, 155.95 MPa, 146.48 MPa, 181.94 MPa, 181.35 MPa, 141.02 MPa, 188.73 MPa, 168.30 MPa, 188.13 MPa, 162.61 MPa, 177.13 MPa, 190.71 MPa, or 204.29 MPa; and / or,

[0099] CS_80 of the strengthened glass ceramic is 142.01 MPa, 111.53 MPa, 100.86 MPa, 140.44 MPa, 130.30 MPa, 110.00 MPa, 140.99 MPa, 129.89 MPa, 119.54 MPa, 117.60 MPa, 130.38 MPa, 138.72 MPa, or 152.35 MPa; and / or,

[0100] The DOL_0 of the strengthened glass ceramic is 185.12 μm, 185.63 μm, 176.34 μm, 185.81 μm, 191.19 μm, 192.04 μm, 189.59 μm, 199.08 μm, 164.11 μm, 187.76 μm, 191.43 μm, 197.80 μm or 215.20 μm.

[0101] As an optional embodiment, 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 vertical downward load at a rate of 10 mm / min to the center of the main surface of the strengthened glass ceramic with a thickness greater than 0.7 mm, and the single rod static pressure strength of the strengthened glass ceramic is greater than 800 N, preferably greater than 850 N; and / or,

[0102] The 2.5 m fixed point height drop test is performed on the strengthened glass ceramic with a thickness greater than 0.7 mm by using 80 mesh silicon carbide sandpaper, and if the glass sample does not break after dropping, it is recorded as passing, and the passing rate of the strengthened glass ceramic is ≥ 50%, preferably ≥ 60%, more preferably ≥ 70%; the passing rate is based on the test of at least 10 samples; and / or,

[0103] The center ball impact energy that the strengthened glass ceramic can withstand is tested by using a 130 g steel ball to impact the strengthened glass ceramic with a thickness greater than 0.7 mm, and the center ball impact energy that the strengthened glass ceramic can withstand is greater than 0.7 J, preferably greater than 0.8 J.

[0104] As an optional embodiment, the strengthened glass ceramic is prepared by chemical strengthening treatment of a glass ceramic with a fracture toughness of not less than 1.40 MPa·m 0.5 , preferably, the strengthened glass ceramic is prepared by at least two steps of chemical strengthening treatment of a glass ceramic with a fracture toughness of not less than 1.40 MPa·m 0.5 , more preferably, the strengthened glass ceramic is prepared by first placing a glass ceramic with a fracture toughness of not less than 1.40 MPa·m 0.5 in a molten salt bath containing sodium salt with a mass percentage of sodium salt greater than or equal to 20% for the first step of strengthening treatment, and then placing the glass ceramic in a molten salt bath containing potassium salt with a mass percentage of potassium salt greater than or equal to 90% for the second step of chemical strengthening treatment.

[0105] In the present application, preferably, the strengthened glass ceramic is made to achieve the desired stress distribution structure by at least two chemical strengthening processes, respectively for the purpose of forming a specific deep stress structure and forming a specific surface stress structure, thereby achieving the improvement of the extrusion resistance and impact resistance of the strengthened glass ceramic, and making the strengthened glass ceramic have excellent extrusion resistance and excellent impact resistance at the same time. Preferably, by using an inorganic salt composition containing Na + as the molten salt salt bath in the first step of the strengthening process, Na + in the salt bath is ion-exchanged with Li + in the glass ceramic, a high depth of compressive stress layer DOL_0 and a high deep stress are obtained; by using an inorganic salt composition containing K + as the molten salt salt bath in the second step of the chemical strengthening, K + in the salt bath is ion-exchanged with Na + in the glass ceramic, Na + in the glass ceramic from the surface to a certain depth inside the glass ceramic is exchanged as K + as much as possible, and the strengthened glass ceramic obtains a high surface compressive stress level.

[0106] In a second aspect, a cover glass is provided, which is made of the strengthened glass ceramic according to any one of the embodiments of the first aspect.

[0107] In a third aspect, an electronic device is provided, which comprises the strengthened glass ceramic according to any one of the embodiments of the first aspect.

[0108] As an optional embodiment, the electronic device comprises a housing assembled on the outer side of the electronic device, and the housing comprises the strengthened glass ceramic according to any one of the embodiments of the first aspect.

[0109] 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 one of the embodiments of the first aspect.

[0110] As an optional embodiment, the housing comprises a rear cover assembled on the rear side of the electronic device, and the rear cover comprises the strengthened glass ceramic according to any one of the embodiments of the first aspect.

[0111] As an optional embodiment, the electronic device further comprises a camera assembly located inside the housing, and 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 the embodiments of the first aspect.

[0112] As an optional embodiment, the electronic device further comprises a middle frame comprising the strengthened glass ceramic according to any one of the embodiments of the first aspect.

[0113] 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 the display screen cover plate, the back cover, the camera protection cover plate, and the middle frame, which are made of the strengthened glass ceramic according to any one of the embodiments of the first aspect.

[0114] In a fourth aspect, a glass device is provided, comprising the strengthened glass ceramic according to any one of the embodiments of the first aspect.

[0115] Compared with the prior art, one or more of the above technical solutions provided in the present application have the following advantages:

[0116] In the present application, the zinc-aluminum spinel-magnesium-aluminum spinel solid solution is used as the main crystal phase of the glass ceramic, so that the glass ceramic has high intrinsic strength. The glass ceramic is chemically strengthened, and the surface composition and stress distribution of the prepared strengthened glass ceramic meet specific requirements, especially the surface Na2O content, the surface K2O content, the K + diffusion depth, the depth of the position where the Na + concentration maximum meets specific requirements, and the thickness, K + diffusion depth (or K + exchange (layer) depth) DOL_K, |CT-AV|, and the compression stress layer depth DOL_0 of the strengthened glass ceramic meet the requirements of formula A, which significantly improves the mechanical properties of the strengthened glass ceramic, so that the strengthened glass ceramic has excellent extrusion resistance and impact resistance. The application of the strengthened glass ceramic in electronic devices enables the electronic devices to meet the application environment with high requirements for extrusion resistance and / or impact resistance, such as better matching the application requirements in water environment (such as deep sea environment), and can be applied in deep water environment. BRIEF DESCRIPTION OF DRAWINGS

[0117] 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 regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor.

[0118] Figure 1 The XRD pattern comparison chart of the glass ceramic and the strengthened glass ceramic provided in Embodiment 1 of the present application.

[0119] Figure 2 A comparison chart of transmittance curves of the glass-ceramics and the strengthened glass-ceramics provided in Embodiment 1 of the present application.

[0120] Figure 3 K element concentration distribution curve and Na element concentration distribution curve of the strengthened glass-ceramics of Embodiment 1 of the present application measured by EPMA.

[0121] Figure 4 SLP stress distribution curve of the strengthened glass-ceramics of Embodiment 1 of the present application measured by SLP-2000.

[0122] Figure 5 A structural schematic diagram of the strengthened glass-ceramics of the present application.

[0123] Figure 6 A process schematic diagram of the single-rod static pressure strength test provided in Embodiment 1 of the present application, wherein 30 is a pressure rod, 31 is a strengthened glass-ceramics sample / sheet to be tested, and 32 is a jig.

[0124] Figure 7 A structural schematic diagram of the jig used in the single-rod static pressure strength test provided in Embodiment 1 of the present application.

[0125] Figure 8 A cross-sectional structural schematic diagram of the jig used in the single-rod static pressure strength test provided in Embodiment 1 of the present application.

[0126] Figure 9 A front side structural schematic diagram of the electronic device mentioned in the embodiment of the present application.

[0127] Figure 10 A back side structural schematic diagram of the electronic device mentioned in the embodiment of the present application.

[0128] Figure 11 A structural schematic diagram of the electronic device mentioned in the embodiment of the present application Figure 1 .

[0129] Figure 12 A structural schematic diagram of the electronic device mentioned in the embodiment of the present application Figure 2 .

[0130] Fig. 1 is a structural schematic diagram of an electronic device according to the present application.

[0131] 20 - strengthened glass-ceramics, 21 - main surface of the strengthened glass-ceramics, 22 - surface compressive stress layer, 23 - deep compressive stress layer, 24 - tensile stress layer, t - thickness of the strengthened glass-ceramics, d1 - DOL_K, d2 - DOL_Na, d3 - DOL_0. DETAILED DESCRIPTION

[0132] The embodiments of the present application will be described in detail below with 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 obtained by commercial purchase.

[0133] The endpoints of the ranges and any values described herein are not limited to the precise values stated. The endpoints of the ranges and the values stated are approximations that are used in the art to describe the ranges and values. The endpoints of the ranges and the values stated are not to be construed as limiting. Ranges can be expressed as from one value and / or to another value. When two values are expressed as a range, e.g. 0.1 to 10, it is intended to include from the lower value and / or to the upper value. For values which are less than one, one digit is removed from the left of the number values which contains the decimal point, e.g. ranges which are less than 0.1 are expressed by removing the first zero and expressing the range as from 1 to 10, and vice versa. It is to be expected that values and ranges which are inherently combinable can be combined and / or commutated to form one or more new values and / or ranges. The terms "optional", "optionally" mean that the subsequently described event or circumstance can or can not occur or hence the feature can or can not be present. The term "and / or" is inclusive, e.g. "A and / or B" means only A, or only B, or both A and B.

[0134] Terminology and test methods:

[0135] In the present application, glass-ceramics are a kind of solid composite materials containing both glass phase and crystal phase (or also known as microcrystalline phase, crystalline phase, crystalline phase) prepared by targeted and controlled heat treatment of base glass. Glass-ceramics are also known as microcrystalline glass or crystallized glass.

[0136] In the present application, strengthened glass-ceramics refer to solid composite materials obtained by chemical strengthening treatment of glass-ceramics. It should be understood that during chemical strengthening treatment, alkali metal ions with large ionic radius (such as potassium ions or sodium ions) in the molten salt bath (or also known as molten salt bath) will replace alkali metal ions with small ionic radius (such as sodium ions or lithium ions) in the glass-ceramics, thereby generating an exchange ion volume difference and generating a compressive stress (or also known as a compressive stress) on the surface of the glass-ceramics.

[0137] In the present application, base glass refers to glass that has not been subjected to nucleation treatment, crystallization treatment and strengthening treatment, or also known as base glass.

[0138] In the present application, the composition at the center of the strengthened glass-ceramics refers to the composition at or near the center of the depth or thickness of the strengthened glass-ceramics, that is, the composition of the region in the strengthened glass-ceramics that has not been subjected to ion exchange. It should be understood that the composition at the center of the strengthened glass-ceramics is the same as or substantially the same as the composition of the glass-ceramics used to prepare the strengthened glass-ceramics but has not been subjected to chemical strengthening treatment.

[0139] In the present application, the main crystal phase (or also referred to as the primary crystal phase) refers to a crystal phase with a higher weight content (or also referred to as a weight percentage, a mass percentage) than other crystal phases present in the glass-ceramic.

[0140] In the present application, the total content of crystal phase refers to the percentage of the total mass of crystal phase or crystal in the glass-ceramic to the mass of the glass-ceramic, or also referred to as the crystallinity of the glass-ceramic.

[0141] In the present application, the main surface refers to the surface with the largest surface area, such as the upper surface or the lower surface of a horizontally placed glass-ceramic sheet.

[0142] In the present application, the wavelength range of visible light refers to 360 nm to 740 nm.

[0143] In the present application, when light of a certain wavelength is irradiated onto the main surface of the 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.

[0144] 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 target crystals or crystal phases in the base glass through heat treatment.

[0145] 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 referred to as a scattered light photoelastic stress meter).

[0146] 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.

[0147] In the present application, CS_50 and CS_80 respectively refer to the compressive stress values at depths of 50 μm and 80 μm from the main surface of the self-strengthening glass-ceramic, with the unit of MPa, which are obtained by SLP-2000 stress meter.

[0148] In the present application, DOL_0 refers to the depth of the compressive stress layer, or the depth of the compressive stress layer, and specifically refers to the distance from any main surface of the strengthened glass-ceramic to the position close to the surface where the compressive stress is zero, which is obtained by SLP-2000 stress meter.

[0149] In the present application, the test method of the foregoing stress performance is as follows: the |CT_CV|, |CT_AV|, CS_50, CS_80 and DOL_0 of the strengthened glass ceramic are tested by using an SLP 2000 stress meter. The related parameter settings of the stress meter are as follows: the light source wavelength is 518 nm, 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 300 μsec.

[0150] In the present application, the SOC (photoelastic coefficient) refers to the photoelasticity of a transparent material after being stressed, which mainly refers to the birefringence phenomenon caused by anisotropy.

[0151] In the present application, the DOL_K refers to the K + diffusion depth, or K + diffusion layer depth, or K + exchange (layer) depth, specifically, 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 referred to as the K element concentration distribution curve) is equal to 0.000 for the first time, which is obtained by testing with a JEOL electron probe EPMA-1720HT. In the present application, the K + depth in the concentration distribution curve, the surface K + diffuses into the glass ceramic after ion exchange, and with the increase of the depth, the K + amount in the glass ceramic becomes less and less, and finally to the depth at which the slope value of the curve is equal to 0.000 for the first time, the K + stops diffusing inward.

[0152] In the present application, the DOL_Na refers to the Na + depth at which the maximum concentration is located, specifically, the depth from any main surface of the strengthened glass ceramic to the Na + depth at which the slope value of the concentration distribution curve (or also referred to as the Na element concentration distribution curve) is equal to 0.000 for the first time, which is obtained by testing with a JEOL electron probe EPMA-1720HT. In the present application, the Na + depth in the concentration distribution curve, the surface Na + is exchanged by K + and has a low concentration, and even possibly 0, and with the increase of the depth, the K + exchange Na + becomes more and more difficult, and the Na +The amount in the glass-ceramics increases more and more, and finally reaches the depth where the curve slope value is equal to 0.000 for the first time, Na + The concentration reaches a maximum value.

[0153] Electron Probe X-ray Microanalysis (EPMA) test: a strengthened glass-ceramic sample to be tested is taken, one of the surfaces perpendicular to the main surface is mechanically ground to remove the strengthening layer (the amount of wear removal is 500 μm or more), a cross-section sample is prepared, the ground cross-section is treated with 30 nm carbon spraying, a linear line in the thickness direction is selected along the ground cross-section by a focused electron beam, and the element composition and element concentration distribution in the thickness direction are obtained. The electron probe X-ray microanalyzer used in the present application is EPMA-1720HT of Shimadzu, the acceleration voltage is 15 kV, the probe current is 100 nA, the beam size is MIN, the step interval is 1 μm, the time is 1 s / point; the light splitting crystal is RAP (Na Kα ray), the light splitting crystal is PET (K Kα ray); the test elements are Na and K.

[0154] In the present application, P1 refers to the absolute value of the average slope of the K element concentration distribution curve between the depth of 0 microns and the depth of DOL_K in the K element concentration distribution curve measured by EPMA. Specifically, P1 = (K element concentration at a depth of 0 microns - K element concentration at a depth of DOL_K) / DOL_K, with a unit of wt% / μm.

[0155] In the present application, P2 refers to the absolute value of the average slope of the Na element concentration distribution curve between the depth of 0 microns and the depth of DOL_Na in the Na element concentration distribution curve measured by EPMA. Specifically, P2 = (Na element concentration at a depth of DOL_Na - Na element concentration at a depth of 0 microns) / DOL_Na, with a unit of wt% / μm.

[0156] In the present application, P 5-8 refers to the absolute value of the average slope of the K element concentration distribution curve between the depth of 5 μm and the depth of 8 μm in the K element concentration distribution curve measured by EPMA. Specifically, P 5-8 = (K element concentration at a depth of 5 μm - K element concentration at a depth of 8 μm) / 3, with a unit of wt% / μm.

[0157] In the present application, the SLP stress distribution curve refers to the corresponding relationship curve of stress and depth obtained by test using a scattered light photoelastic stress meter SLP-2000.

[0158] In the present application, K 50-80K refers to the absolute value of the average slope of the SLP stress distribution curve measured by the SLP-2000, specifically the segment between a depth of 50 μm and a depth of 80 μm. 50-80 = (Stress value at a depth of 50μm - Stress value at a depth of 80μm) / 30, with units of MPa / μm.

[0159] In this application, K 80DOL K refers to the absolute value of the average slope of the SLP stress distribution curve measured by the SLP-2000, specifically the segment between depths of 80 μm and DOL_0. 80DOL = (Stress value at depth 80μm - Stress value at depth DOL_0) / (DOL_0-80), unit is MPa / μm.

[0160] In this application, Vickers hardness refers to a standard for expressing the hardness of materials proposed by Robert L. Smith and George E. Sandland in 1921 at Vickers Ltd.

[0161] The Vickers hardness test method in this application is as follows: A small circular piece of glass-ceramic or reinforced glass-ceramic with a diameter of 46 mm and a thickness of 0.9 mm is prepared. A clean glass sample without visible scratches, dents, cracks, or other damage is selected as the test sample. The Vickers hardness is then measured using a Vickers hardness tester. The Vickers hardness tester used in this application is a digital display low-load Vickers hardness tester, model VTD405, manufactured by Beijing Kewei Technology Co., Ltd. Test conditions: load 300 gf, loading time 10 s, and the validity of the indentation conforms to the standard "GB / T37900-2019 Test Method for Hardness and Fracture Toughness of Ultra-thin Glass: Low-load Vickers Hardness Indentation Method". Measurements are taken at three different locations on the surface of the same test sample, and the average of the three measurements is recorded as the Vickers hardness result of the test sample.

[0162] In this application, the thickness of the glass-ceramic was obtained by micrometer measurement. It should be understood that, in the thickness direction, the degree of ion exchange varies gradient from the surface to the center, and the overall increase (mass) in Na-K and / or Li-Na exchange generally does not exceed 1.5% of the total sample mass. Therefore, the expansion effect in the thickness direction is extremely slight, and the thickness can be approximated as essentially unchanged. That is, the thickness change of the glass-ceramic before and after chemical strengthening is very small and can be basically ignored; the thickness of the glass-ceramic is essentially the same as the thickness of the strengthened glass-ceramic obtained.

[0163] 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.

[0164] In the present application, the size specification of the glass-ceramic sheet is tested by a two-dimensional measuring machine (instrument model Miyu MY-YXCL-4030).

[0165] In the present application, the crystalline phase composition, the total content of crystalline phase (or also called crystallinity), and the average crystal size of the glass-ceramics are confirmed by XRD test, which is as follows:

[0166] (1) XRD test: The glass-ceramics or strengthened glass-ceramics of the present application are crushed and ground into samples with a particle size of less than 75 μm, and the ground samples are tested by an X-ray diffractometer to obtain XRD diffraction peak curves and XRD diffraction data. The X-ray diffractometer used in the present application is Shimadzu XRD-6100, the target material is copper, 2θ = 10°-80°, the scanning speed is 2° / min, the working voltage is 40 kV, and the working current is 30 mA.

[0167] (2) Determination of crystalline phase: The XRD diffraction data are analyzed by Jade software (JADE Standard 8.6) to determine the crystalline phase in the sample.

[0168] (3) Determination of the total content of crystalline phase (or also called crystallinity): The test results of XRD (RAW format) are imported into Jade software for fitting and calculation, so as to determine the total content of crystalline phase of the sample. Specifically, the ratio of the peak area of the fitted crystalline phase to the total peak area of the fitted crystalline phase is recorded as the total content of crystalline phase of the sample.

[0169] (4) Determination of the average crystal size: According to the Scherrer formula D = Kλ / (βcosθ), the average crystal size (or also called average grain size) of the sample can be calculated from the result data obtained by 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 Jade software, and the fitting report is output by Jade. 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 radian: β = (FWHM / 180×3.14), 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.

[0170] In the present application, the transmittance of the glass-ceramics is tested by a haze meter according to the national standard GB / T 7962.12-2010 Optical Glass - Test Methods - Part 12: Spectral Transmittance. Specifically, the transmittance of 5 pieces of glass-ceramics of the same batch to light of different wavelengths is tested by a haze meter. The average of the transmittance of the 5 pieces of glass-ceramics to light of 550 nm wavelength is taken as the transmittance result of the glass-ceramics to light of 550 nm wavelength. The haze meter used in the present application is a Konica Minolta Spectrophotometer CM-3600A from Japan, the light receiving optical system is transmission, the spectral method is plane diffraction grating, the wavelength range is 360 nm-740 nm, the wavelength interval is 10 nm, the illumination light source is 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%.

[0171] In the present application, the test method for the surface Na2O mass percentage (or also referred to as the surface Na2O concentration) of the strengthened glass-ceramics is as follows: the content of Na element on the surface of the strengthened glass-ceramics is measured by an X-ray fluorescence spectrometer (XRF), and then the surface Na2O mass percentage is calculated. The calculation method is as follows: surface Na2O mass percentage = (content of Na element on the surface x relative molecular mass of Na2O) / (relative atomic mass of Na element x 2). It should be understood that the content of Na element on the surface = mass of Na element / total mass of elements, and the total mass of elements = total mass of oxides. The equipment 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 30 kV, the current is 80 mA, the collimator is 0.40, the crystal selection is AxO3, the detector selection is FPC, and the test range is a circle with a diameter of 29 mm. The test method uses the X_UQ method in the OXSAS analysis software.

[0172] In the present application, the test method for the surface K2O mass percentage (or also referred to as the surface K2O concentration) of the strengthened glass-ceramics is as follows: the content of K element on the surface of the strengthened glass-ceramics is measured by an X-ray fluorescence spectrometer (XRF), and then the surface K2O mass percentage is calculated. The calculation method is as follows: surface K2O mass percentage = (content of K element on the surface x relative molecular mass of K2O) / (relative atomic mass of K element x 2). It should be understood that the content of K element on the surface = mass of K element / total mass of elements, and the total mass of elements = total mass of oxides. The equipment 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 selection is LiF200, the detector selection is 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.

[0173] In the present application, the XRF instrument test uses a non-standard test, 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.

[0174] In the present application, when testing with an XRF instrument, the strengthened glass ceramic sheet is directly cut into the appropriate size (such as 34mm*34mm), placed flat in the sample box, and covered with the test aperture, and the test can be performed.

[0175] In the present application, the test of fracture toughness is performed according to the standard of “GB / T 37900-2019 Ultra-thin glass hardness and fracture toughness test method small load Vickers hardness indentation method”.

[0176] 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.

[0177] Indentation fracture toughness calculation formula:

[0178]

[0179] Wherein, IFR: indentation fracture toughness, unit: megapascal two-thirds of the first power 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).

[0180] In the present application, the single rod static pressure strength test: place the strengthened glass ceramic sample to be tested in a customized jig (as shown in Figure 6 ), and then place it on the bottom ring of a tensile testing machine (LT-850A), start the test software, and set the moving speed of the extrusion rod (rod diameter 10mm, ball head diameter 10mm) to 10mm / min, click start test, and 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. The test process is shown in Figure 6 .

[0181] The test software will automatically read the force (N) at which the strengthened glass ceramic sample breaks, which is recorded as the single bar static pressure strength that it can withstand. Ten strengthened glass ceramic samples in the same state are tested, and the average of the test results is taken as the single bar static pressure strength of the strengthened glass ceramic sample to be tested.

[0182] The custom jig in the test method is a cylindrical jig with a diameter of 65 mm and a height of 20 mm, and the specific structure of the custom jig is as shown in Figure 7 、 Figure 8 wherein Φ1 = 65 mm, Φ2 = 46.02 mm, Φ3 = 44 mm, h1 = 20 mm, h2 = the thickness of the strengthened glass ceramic sample to be tested, and h3 = 15 mm. The height h2 of the sample slot in the custom 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 custom jig. The stepped blind hole for placing the sample for testing in the custom jig is coaxial with the custom jig. The material of the jig is acrylic material.

[0183] In the present application, a 2.5 m fixed-point height drop test is used to test the pass rate of the strengthened glass ceramic, which is used to characterize the anti-drop impact performance of the strengthened glass ceramic. The pass rate here refers to a plurality of identical strengthened glass ceramic samples, which are respectively subjected to a drop test from a 2.5 m fixed-point height, and the number of samples that pass the drop test is divided by the total number of test samples to calculate the pass rate. After the drop test, if the glass sample does not break, it is recorded as passing, otherwise it is recorded as not passing. In the present application, at least 10 identical strengthened glass ceramic samples are taken for testing in each batch.

[0184] Specifically, the method for a single sample to undergo a 2.5 m fixed-point height drop test is as follows:

[0185] Step 1: Paste 80-mesh sandpaper on the lower surface of the 160g model machine, and place the model machine on the green chart LT-SKDL-CD type drop machine;

[0186] Step 2: Place the strengthened glass ceramic sample to be tested with a diameter of 46 mm and a thickness of 0.7 mm to 1.05 mm directly below the model machine, so that the strengthened glass ceramic sample faces the sandpaper. Make the model machine drop from a 2.5 m drop height once, and impact the strengthened glass ceramic sample directly below the model machine. If the strengthened glass ceramic sample does not break, it is recorded as passing, otherwise it is recorded as not passing.

[0187] In the present application, a 130g steel ball is used to perform drop ball impact test on the strengthened glass ceramic, to test the central drop ball impact energy that the strengthened glass ceramic can withstand, for representing the anti-drop ball impact performance of the strengthened glass ceramic. Specifically, a strengthened glass ceramic sample piece with a diameter of 46mm and a thickness of 0.7mm-1.05mm to be tested is placed in a customized fixture, at a test position of a drop ball impact testing machine (MY-GXDL-1500), a test software is started, the fixture position is calibrated by infrared rays, a 130g steel ball is used to perform limit drop ball test on the center point of the strengthened glass ceramic, the initial impact height of the drop ball is set to 0.3m, if the sample piece is not broken after the drop ball impacts the strengthened glass ceramic sample piece from the initial impact height, the drop ball impact height is increased by 0.05m each time, the strengthened glass ceramic sample piece is continuously impacted until the strengthened glass ceramic sample piece is broken.

[0188] The last drop ball impact height before the strengthened glass ceramic sample piece is broken is recorded as the anti-drop ball impact height. For example, if the limit drop ball test is performed by increasing the drop ball impact height by 0.05m each time, when the drop ball impact height at which the sample piece is broken is 0.5m, the anti-drop ball impact height of the sample piece is 0.45m.

[0189] Then, the central drop ball impact energy that the strengthened glass ceramic can withstand is calculated according to the formula: E=mgh.

[0190] Wherein: m is the mass of the steel ball; the unit is kg; h is the anti-drop ball impact height; the unit is m; g is the acceleration of gravity, the value is 9.8, and the unit is m / s 2 ; E is the central drop ball impact energy; the unit is J.

[0191] The electronic equipment used in deep-sea exploration environment, diving environment and the like encounters damage risks including water pressure extrusion problem in addition to impact problem. Although the current glass ceramic has better performance than general glass, the anti-extrusion performance and the anti-impact performance still need to be further improved.

[0192] Without being limited by any theory, spinel crystal has excellent characteristics such as high hardness and high modulus, and the strengthened glass ceramic prepared by using glass ceramic with spinel crystal phase as the main crystal phase for chemical strengthening has better anti-extrusion performance and anti-impact performance than the strengthened glass ceramic prepared by using ordinary glass.

[0193] The chemical formula of the spinel crystal is AB2O4, wherein 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. Since Al-O, Mg-O and Zn-O can form strong ionic bonds, the structure is firm, the hardness is large, and the chemical properties are stable. The Mohs hardness of the spinel crystal is basically between 7 and 8, close to 8. Therefore, theoretically, a spinel glass ceramic with good mechanical properties can be obtained by controllably precipitating zinc spinel (or also referred to as zinc aluminum spinel) and / or magnesium spinel (or also referred to as magnesium aluminum spinel) and / or zinc magnesium spinel solid solution (Zn, Mg)Al2O4 in the glass.

[0194] To this end, the present application adopts a glass ceramic containing spinel crystals satisfying specific composition and structure to prepare a strengthened glass ceramic material with desired extrusion resistance and impact resistance. The glass ceramic adopted in the present application is rich in high-strength spinel crystals and has a high-strength glass phase structure, and the mutual coordination of the crystal phase structure and the glass phase structure endows the glass ceramic with high inherent strength or intrinsic strength. The present application makes the surface composition and stress distribution of the glass ceramic after chemical strengthening satisfy specific requirements, so as to endow the prepared strengthened glass ceramic with a stress structure and stress level that realizes high extrusion resistance and high impact resistance, and thus obtain a strengthened glass ceramic with excellent extrusion resistance and excellent impact resistance.

[0195] It can be understood that the "surface composition" in the present application can be the material composition or the component distribution of the surface of the substrate glass, the glass ceramic or the strengthened glass ceramic, can also be the mass percentage of a certain component, the molar percentage of a certain component, the mass percentage relationship between two or more than two material components, the mass content relationship between two or more than two material components, can also be the molar content relationship between two or more than two material components, can also be the combination of the foregoing, and the like. For example: the mass percentage of Na2O on the surface of the strengthened glass ceramic or the mass percentage of K2O on the surface of the strengthened glass ceramic, for example: the mass percentage of Na2O on the surface of the strengthened glass ceramic and the mass percentage of K2O on the surface of the strengthened glass ceramic, for example: the mass percentage of K2O from the main surface of the strengthened glass ceramic, and the like. + (K element) diffusion depth and the depth of the position where the Na + concentration maximum is located.

[0196] In some embodiments of the present application, a strengthened glass ceramic is provided, wherein 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;

[0197] The surface K2O mass percentage of the strengthened glass ceramic is 2.50% to 7.50% as measured by XRF in terms of mass percentage of oxide, preferably, the surface K2O mass percentage of the strengthened glass ceramic is 3.00% to 7.00%, more preferably, the surface K2O mass percentage of the strengthened glass ceramic is 3.50% to 7.00%;

[0198] The surface Na2O mass percentage of the strengthened glass ceramic is less than or equal to 0.010% as measured by XRF in terms of mass percentage of oxide, 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%;

[0199] The strengthened glass ceramic satisfies 8.00 μm≤DOL_K≤20.00 μm as measured by EPMA, preferably, 8.50 μm≤DOL_K≤18.00 μm, more preferably, 9.00 μm≤DOL_K≤16.00 μm, wherein DOL_K is the depth of the maximum K + diffusion depth;

[0200] The strengthened glass ceramic satisfies 30.00 μm≤DOL_Na≤60.00 μm as measured by EPMA, preferably, 34.00 μm≤DOL_Na≤59.00 μm, more preferably, 37.00 μm≤DOL_Na≤59.00 μm, wherein DOL_Na is the depth of the maximum Na + concentration maximum;

[0201] The strengthened glass ceramic satisfies A=(t×DOL_K) / (|CT-AV|×(DOL_0 / t)), 850≤A≤4000, preferably, 850≤A≤3000, more preferably, 900≤A≤2000; wherein t is the thickness of the strengthened glass ceramic, in units of μm; DOL_K is the depth of the maximum K +Diffusion depth, measured by EPMA, unit: pm; |CT-AV| is the absolute value of the average tensile stress of the strengthened glass ceramic, measured by SLP_2000, unit: MPa; DOL_0 is the depth of the compressive stress layer of the strengthened glass ceramic, measured by SLP_2000, unit: pm; in formula A, the data are substituted into the formula according to the above unit requirements, and the calculation result is obtained, and the unit is not involved in the calculation.

[0202] 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.

[0203] 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, and by chemically strengthening the glass ceramic and making the surface composition and stress distribution of the prepared strengthened glass ceramic meet specific requirements, especially the surface Na2O content, surface K2O content, K + Diffusion depth, Na + The depth of the position where the concentration maximum is located meets specific requirements, and at the same time, the thickness, K + Diffusion depth (or K + exchange (layer) depth) DOL_K, |CT-AV| and the depth of the compressive stress layer DOL_0 meet the requirements of formula A, and the mechanical properties of the strengthened glass ceramic are significantly improved, so that the strengthened glass ceramic simultaneously obtains excellent extrusion resistance and impact resistance.

[0204] 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 2.50%, 3.00%, 3.50%, 4.00%, 4.50%, 5.00%, 5.50%, 6.00%, 6.50%, 7.00%, 7.50%, 5.62%, 4.66%, 6.78%, 4.95%, 3.86%, 4.96%, 4.55%, 4.53%, 4.04%, 5.73%, 5.39%, 6.11%, or 5.89%, or can be a value within a value range formed by any two specific values as endpoints, as long as the strengthened glass ceramic 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 ceramic with the required performance of the present application can be obtained.

[0205] In some embodiments, the surface Na20 content 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 aforementioned specific numerical values as endpoints, as long as the strengthened glass ceramic having the desired properties herein is obtained. It will be understood that any of the above-mentioned ranges can be combined with any of the other ranges, as long as the strengthened glass ceramic having the desired properties herein is obtained.

[0206] In some embodiments, the DOL K of the strengthened glass ceramic can satisfy 10.00 pm < DOL K < 15.00 pm, 11.00 pm < DOL K < 14.00 pm, 15.00 pm < DOL K < 20.00 pm, or 12.00 pm < DOL K < 19.00 pm. In some embodiments, the DOL K of the strengthened glass ceramic can be 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, 12.10 pm, 11.00 pm, 9.40 pm, 15.10 pm, 14.10 pm, 13.00 pm, 11.10 pm, 19.10 pm, 18.00 pm, or 17.10 pm, or a value within a range having any two of the aforementioned specific numerical values as endpoints, as long as the strengthened glass ceramic having the desired properties herein is obtained. It will be understood that any of the above-mentioned ranges can be combined with any of the other ranges, as long as the strengthened glass ceramic having the desired properties herein is obtained.

[0207] In some embodiments, the strengthened glass-ceramics can satisfy: 40.00 pm ≤ DOL Na≤ 55.00 pm, 43.00 pm ≤ DOL Na≤ 52.00 pm, or 45.00 pm ≤ DOL Na≤ 50.00 pm. In some embodiments, the strengthened glass-ceramics can have a DOL Naof 30.00 pm, 35.00 pm, 37.00 pm, 40.00 pm, 42.00 pm, 45.00 pm, 47.00 pm, 50.00 pm, 52.00 pm, 55.00 pm, 57.00 pm, 60.00 pm, 46.10 pm, 40.00 pm, 55.10 pm, 45.40 pm, 47.10 pm, 58.10 pm, 48.00 pm, 51.10 pm, 38.00 pm, 43.10 pm, 50.30 pm, 50.20 pm, or 56.40 pm, or a value within a range between any two of the above specifically named values as an endpoint, as long as the strengthened glass-ceramics having 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 the strengthened glass-ceramics having the desired properties of the present application can be obtained.

[0208] In some embodiments, the value of Formula A can be 850, 950, 1050, 1150, 1250, 1350, 1450, 1550, 1650, 1750, 1850, 1950, 2050, 2150, 2250, 2350, 2450, 2550, 2650, 2750, 2850, 2950, 3050, 3150, 3250, 3350, 3450, 3550, 3650, 3750, 3850, 3950, 4000, 1039, 1150, 1520, 910, 1542, 1469, 935, 995, 1780, 1054, 1500, 2010, or 2440, or a value within a range between any two of the above specifically named values as an endpoint, as long as the strengthened glass-ceramics having 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 the strengthened glass-ceramics having the desired properties of the present application can be obtained.

[0209] In some embodiments of the present application, the strengthened glass-ceramics satisfy: along the thickness direction of the strengthened glass-ceramics, the concentration of K + decreases nonlinearly from the main surface of the strengthened glass-ceramics to the center of the strengthened glass-ceramics. In the present application, the K + concentration distribution curve from the main surface to the interior of the strengthened glass-ceramics measured by EPMA shows a nonlinear decreasing trend. +After ion exchange, K + The amount of K + in the glass ceramic increases with the depth, and finally, at the depth where the slope of the curve is equal to 0.000 for the first time, the amount of K + in the glass ceramic reaches a maximum value.

[0210] In some embodiments of the present application, the strengthened glass ceramic satisfies: along the thickness direction of the strengthened glass ceramic, the concentration of Na + firstly increases nonlinearly and then decreases nonlinearly from the main surface of the strengthened glass ceramic to the center of the strengthened glass ceramic. In the present application, in the Na + concentration distribution curve of the strengthened glass ceramic from the main surface to the interior, the concentration of Na + at the surface is low, even possibly 0, and with the increase of the depth, the difficulty of exchanging Na + with K + increases gradually, and the amount of Na + in the glass ceramic increases with the depth, and finally, at the depth where the slope of the curve is equal to 0.000 for the first time, the amount of Na + reaches a maximum value.

[0211] In the present application, by satisfying specific requirements for the average slope of the K element concentration distribution curve and / or the Na element concentration distribution curve in different depth ranges of the strengthened glass ceramic, it is beneficial to make the strengthened glass ceramic achieve the desired stress distribution structure, and thus it is beneficial to make the strengthened glass ceramic simultaneously obtain excellent impact resistance and extrusion resistance.

[0212] In some embodiments of the present application, the strengthened glass ceramic satisfies:

[0213] The K element concentration distribution curve is obtained by EPMA, in which the horizontal axis is the depth in μm from the main surface of the strengthened glass ceramic, and the vertical axis is the K element concentration in the mass percentage of element basis. In the obtained K element concentration distribution curve: the absolute value P1 of the average slope of the K element concentration distribution curve between the depth of 0 μm and the depth of DOL_K is 0.150-1.000, preferably, P1 is 0.150-0.800, and more preferably, P1 is 0.150-0.600.

[0214] In some embodiments, in the K element concentration distribution curve measured by EPMA: the absolute value of the average slope of the K element concentration distribution curve between a depth of 0 micrometers and a depth of DOL_K can be 0.150, 0.200, 0.250, 0.300, 0.350, 0.400, 0.450, 0.500, 0.550, 0.600, 0.650, 0.700, 0.750, 0.800, 0.850, 0.900, 0.950, 1.000, 0.380, 0.315, 0.302, 0.530, 0.348, 0.193, 0.445, 0.452, 0.194, 0.440, 0.220, or 0.310, or a value within a range having any two of the above specific numeric values as endpoints, as long as a strengthened glass-ceramic having the desired properties herein is obtained. It will be appreciated that in specific embodiments, any of the above ranges can be combined with any of the other ranges, as long as a strengthened glass-ceramic having the desired properties herein is obtained.

[0215] In some embodiments of the application, the strengthened glass-ceramic satisfies: a K element concentration distribution curve is obtained using EPMA with the horizontal axis as depth in micrometers from the major surface of the strengthened glass-ceramic and the vertical axis as K element concentration in mass percent on an elemental basis, and in the obtained K element concentration distribution curve: the absolute value of the average slope of the K element concentration distribution curve between a depth of 5 micrometers and a depth of 8 micrometers, P 5-8 is 0.50-2.50, preferably, P 5-8 is 0.60-2.00, more preferably, P 5-8 is 0.70-1.50.

[0216] In some embodiments, in the K element concentration distribution curve measured by EPMA: the absolute value of the average slope of the K element concentration distribution curve between a depth of 5 micrometers and a depth of 8 micrometers, P 5-8The values ​​can be 0.50, 0.60, 0.70, 0.80, 0.90, 1.00, 1.10, 1.20, 1.30, 1.40, 1.50, 1.60, 1.70, 1.80, 1.90, 2.00, 2.10, 2.20, 2.30, 2.40, 2.50, 0.74, 1.12, 1.22, 0.99, 1.04, 1.25, 0.76, 0.80, 0.79, 0.95, 0.66, 1.34, or 1.64, or values ​​within a range defined by any two of the above specific values ​​as endpoints, as long as the strengthened glass-ceramic with the desired performance of this 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 with the desired performance of this application is obtained.

[0217] In some embodiments of this application, the reinforced glass-ceramic satisfies the following: EPMA testing is used to obtain a Na element concentration distribution curve with the horizontal axis representing the depth in μm from the main surface of the reinforced glass-ceramic and the vertical axis representing the Na element concentration as a mass percentage based on elemental parameters. In the obtained Na element concentration distribution curve:

[0218] The absolute value of the average slope P2 of the Na element concentration distribution curve between a depth of 0 micrometers and a depth of DOL_Na is 0.01 to 0.05, preferably 0.01 to 0.04, and more preferably 0.01 to 0.03.

[0219] In some embodiments, in the Na element concentration distribution curve measured by EPMA, the absolute value P2 of the average slope of the Na element concentration distribution curve between a depth of 0 micrometers and a depth of DOL_Na can be 0.01, 0.02, 0.03, 0.04, or 0.05, or can be a value within a numerical range formed by any two of the above specific values ​​as endpoints, as long as the strengthened glass-ceramic with the desired performance of this application is obtained. It should be understood that in specific embodiments, any of the above ranges can be combined with any other ranges, as long as the strengthened glass-ceramic with the desired performance of this application is obtained.

[0220] In this application, by ensuring that the average slope of the stress distribution curves in different depth ranges of the reinforced glass ceramic meets specific requirements, it is beneficial to enable the reinforced glass ceramic to achieve the desired stress distribution structure, thereby enabling the reinforced glass ceramic to simultaneously possess excellent impact resistance and extrusion resistance.

[0221] In some embodiments of this application, the reinforced glass-ceramic satisfies:

[0222] The SLP stress profile is obtained using SLP-2000, with the horizontal axis being depth in pm from the main surface of the strengthened glass ceramic, and the vertical axis being stress in MPa, and wherein: the absolute value of the average slope of the SLP stress profile between a depth of 50 pm and a depth of 80 pm, K 50-80 is 1.00 to 2.50, preferably, K 50-80 is 1.00 to 2.40, more preferably, K 50-80 is 1.00 to 2.30.

[0223] In some embodiments, in the SLP stress profile measured by SLP-2000: the absolute value of the average slope of the SLP stress profile between a depth of 50 pm and a depth of 80 pm, K 50-80 may be 1.00, 1.10, 1.20, 1.30, 1.40, 1.50, 1.60, 1.70, 1.80, 1.90, 2.00, 2.10, 2.20, 2.30, 2.40, 2.50, 1.92, 1.48, 1.52, 1.38, 1.70, 1.03, 1.59, 1.28, 2.29, 1.50, 1.56, or 1.73, or can be a value within a range bounded by any two of the foregoing specific values as endpoints, as long as a 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 foregoing 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. In the present application, the SLP stress profile of the strengthened glass ceramic obtained using the SLP-2000 instrument is a non-linear curve, as shown in Figure 4 .

[0224] In some embodiments of the present application, the strengthened glass ceramic satisfies: the SLP stress profile is obtained using SLP-2000, with the horizontal axis being depth in pm from the main surface of the strengthened glass ceramic, and the vertical axis being stress in MPa, and wherein: the absolute value of the average slope of the SLP stress profile between a depth of 80 pm and a depth of DOL_0, K 80DOL-0 is 0.90 to 2.00, preferably, K 80DOL-0 is 0.90 to 1.80, more preferably, K 80 DOL-0 is 0.90 to 1.60.

[0225] In some embodiments, in the SLP stress profile measured by SLP-2000: the absolute value of the average slope of the SLP stress profile between a depth of 80 pm and a depth of DOL_0, K80 DOL-0 may be 0.90, 1.00, 1.10, 1.20, 1.30, 1.40, 1.50, 1.60, 1.70, 1.80, 1.90, 2.00, 1.35, 1.06, 1.05, 1.33, 1.17, 0.98, 1.29, 1.09, 1.42, 1.18, or 1.13, or a value within a range defined by any two of the specifically mentioned 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 ranges can be combined with any other range, as long as the strengthened glass-ceramic has the desired properties.

[0226] In some embodiments of the present application, the strengthened glass-ceramic is in the form of a plate, and 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 in the range of 0.9 mm to 2.0 mm. In the present application, when the thickness of the strengthened glass-ceramic is small, the compression resistance and impact resistance of the strengthened glass-ceramic will be significantly reduced. When the thickness of the strengthened glass-ceramic is too large, on the one hand, the weight will be increased, which is not conducive to the light and thin electronic devices, and on the other hand, the transmittance of the strengthened glass-ceramic will be reduced, which will result in poor transmittance performance.

[0227] In some embodiments, the thickness t of the strengthened glass-ceramic can be not less than 0.95 mm, not less than 1.00 mm, or not less than 1.05 mm. In some embodiments, the thickness t of the strengthened glass-ceramic can be 0.7 mm, 0.8 mm, 0.9 mm, 1.0 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, or 1.5 mm, or a value within a range defined by any two of the specifically mentioned 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 ranges can be combined with any other range, as long as the strengthened glass-ceramic has the desired properties.

[0228] 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 of the strengthened glass-ceramic is the same as or substantially the same as that of the glass-ceramic. Compared with the glass-ceramic before the chemical strengthening treatment (the chemical strengthening treatment will be ion exchange), the composition at the surface of the glass-ceramic article after the chemical strengthening treatment can be different from that of the glass-ceramic before the chemical strengthening treatment. This is because, during the chemical strengthening treatment, the type of alkali metal ions (for example, Li + or Na + ) at the surface of the glass-ceramic just formed will be replaced by larger alkali metal ions (for example, Na + or K ) respectively.+ However, in embodiments, the glass composition and phase assemblage at or near the center of the depth or thickness of the glass-ceramic article can still have the composition and phase assemblage of the as-formed glass-ceramic. That is, in the present application, the composition (e.g., the composition of the compressive stress layer) and phase assemblage at the center of the strengthened glass-ceramic is the same or substantially the same as the glass-ceramic that has not been chemically strengthened.

[0229] In the present application, the glass-ceramic used to make the strengthened glass-ceramic can be made from a base glass that has the same or substantially the same composition as the glass-ceramic, in terms of mass percent of oxides, by heat treatment.

[0230] In some embodiments of the present application, the composition at the center 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 contains Al2O3 in an amount of greater than or equal to 30.00% in terms of mass percent of oxides.

[0231] In the present application, by controlling the mass percent of Al2O3 in the glass-ceramic to be greater than or equal to 30%, on one hand, it can ensure the precipitation of desired amount of the main crystalline phase, so that the glass-ceramic has high intrinsic strength (or also known as inherent strength), on the other hand, it can also make the glass phase contain a certain amount of alumina, 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 degree of network connection 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 making the strengthened glass-ceramic with excellent mechanical strength performance.

[0232] In some embodiments of the present application, the composition at the center 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 contains ZrO2 in an amount of greater than or equal to 3.00% in terms of mass percent of oxides.

[0233] 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 and effectively improve the shatter resistance of the glass-ceramic. On the other hand, zirconia exists in the form of a cube [ZrO8] in the glass phase, which can enhance the interionic force and make the glass structure more compact, thereby 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.

[0234] In some embodiments of the present application, the composition at the center 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 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%. By adjusting and controlling the content range of each oxide component, it is beneficial to ensure that the strengthened glass-ceramic meets the desired crystal phase structure and stress structure, and at the same time, it is beneficial to ensure that the strengthened glass-ceramic has excellent optical performance and high intrinsic strength.

[0235] In the present application, SiO2 is a network-forming oxide of the glass network and is an indispensable component of the glass network structure. An appropriate amount of SiO2 can increase the stability and mechanical strength of the glass, but excessive SiO2 will increase the viscosity of the base glass, making it difficult to melt the glass and thus reducing the formability of the base glass. In the present application, the mass percentage of SiO2 in the composition at the center 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 25.00% to 55.00%, preferably 30.00% to 42.00%, and more preferably 35.00% to 40.00%.

[0236] 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 glass-ceramic used to make the strengthened glass-ceramic or the composition of the base glass can range from 25.00% to 55.00%, from 25.00% to 40.00%, from 40.00% to 55.00%, or from 30.00% to 40.00%, in terms of mass percent of oxides.

[0237] 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 glass-ceramic used to make the strengthened glass-ceramic or the composition of the base glass can range from 25.00% to 55.00%, from 25.00% to 40.00%, from 40.00% to 55.00%, or from 30.00% to 40.00%, in terms of mass percent of oxides.

[0238] 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, and 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-ceramic is also enhanced, and the mechanical properties of the glass-ceramic 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 will easily lead to the rapid crystallization rate, which will cause the substrate glass to devitrify during the normal cooling process. In the present application, the mass percentage of Al2O3 in the composition at the center 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 30.00% to 55.00%, preferably 32.00% to 42.00%, and more preferably 34.00% to 42.00%.

[0239] In some embodiments of the present application, the content of Al2O3 in the composition at the center 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 can be 30.00% to 55.00%, 30.00% to 40.00%, or 40.00% to 55.00% in terms of mass percentage of oxide.

[0240] In some embodiments of the present application, the content of Al2O3 in the composition at the center of the strengthened glass-ceramics or the composition of the glass-ceramics used for preparing the strengthened glass-ceramics or the composition of the base glass can be 30.00%, 30.50%, 31.00%, 31.50%, 32.00%, 32.50%, 33.00%, 33.50%, 34.00%, 34.50%, 35.00%, 35.50%, 36.00%, 36.50%, 37.00%, 37.50%, 38.00%, 38.50%, 39.00%, 39.50%, 40.00%, 40.50%, 41.00%, 41.50%, 42.00%, 42.50%, 43.00%, 43.50%, 44.00%, 44.50%, 45.00%, 45.50%, 46.00%, 46.50%, 47.00%, 47.50%, 48.00%, 48.50%, 49.00%, 49.50%, 50.00%, 50.50%, 51.00%, 51.50%, 52.00%, 52.50%, 53.00%, 53.50%, 54.00%, 54.50%, 55.00%, 35.83%, 36.98%, 36.27%, 37.52%, 36.60%, 37.07%, 34.84%, 34.55% or 35.88%, or a value within a range defined by any two of the above specific values as endpoints, as long as a glass-ceramics or strengthened glass-ceramics 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-ceramics or strengthened glass-ceramics with desired properties of the present application can be obtained.

[0241] In the present application, ZrO2 is an effective nucleating agent, which is precipitated in the form of crystals during the heat treatment of the glass, and the ZrO2 crystals become the crystal nucleus for the growth of subsequent crystals. 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-ceramics obtained after heat treatment of the glass, etc. By adjusting the glass composition, ZrO2 can be precipitated preferentially at the same temperature, followed by the growth of the main crystal phase spinel crystals. 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 cause the melting of the base glass to be difficult, resulting in white unmelted substances in the base glass. In the present application, the mass percentage of ZrO2 in the composition at the center of the strengthened glass-ceramics or the composition of the glass-ceramics used for preparing the strengthened glass-ceramics or the composition of the base glass is 3.00%-8.00%, preferably 4.00%-7.00%, more preferably 5.00%-6.00%.

[0242] In some embodiments of the present application, the content of Zr02in the composition at the center 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 3.00% to 8.00%, 3.00% to 6.00%, or 6.00% to 8.00% by mass percent of oxide.

[0243] In some embodiments of the present application, the content of Zr02in the composition at the center 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 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%, or 5.48% 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 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.

[0244] In the present application, ZnO provides the zinc necessary for the base glass to form the main crystal phase of the zinc-magnesium spinel solid solution crystal phase after crystallization. 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 base glass to form the main crystal phase of the zinc-magnesium spinel solid solution crystal phase after crystallization. MgO can slow the hardening speed of the glass, improve the forming properties of the glass; MgO can also reduce the crystallization tendency and crystallization speed, 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 at the center 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 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%.

[0245] In some embodiments of the present application, the content of ZnO in the composition at the center of the strengthened glass-ceramics or the composition of the glass-ceramics used to prepare the strengthened glass-ceramics or the composition of the base 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%, 14.00%, 15.00%, 10.77%, 10.71%, 10.55%, 10.87%, 11.01%, 11.15%, 10.46% or 10.37% in terms of mass percentage of oxide, or can be a value within a range defined by any two of the above specific numerical values as endpoints, as long as a glass-ceramics or strengthened glass-ceramics 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-ceramics or strengthened glass-ceramics with desired properties of the present application can be obtained.

[0246] In some embodiments of the present application, the content of MgO in the composition at the center of the strengthened glass-ceramics or the composition of the glass-ceramics used to prepare the strengthened glass-ceramics or the composition of the base 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% or 2.89% in terms of mass percentage of oxide, or can be a value within a range defined by any two of the above specific numerical values as endpoints, as long as a glass-ceramics or strengthened glass-ceramics 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-ceramics or strengthened glass-ceramics with desired properties of the present application can be obtained.

[0247] 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-ceramics during heat treatment, resulting in a decrease in the transmittance of the obtained glass-ceramics. Too low Na2O content can lead to an increase in the heat treatment temperature, direct phase separation or precipitation of impurity phases during heat treatment, resulting in glass-ceramics with poor transparency or opaque effect. In the present application, the mass percentage of Na2O in the composition at the center of the strengthened glass-ceramics or the composition of the glass-ceramics used to prepare the strengthened glass-ceramics 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%.

[0248] In some embodiments of the present application, the content of Na20 in the composition at the center of the strengthened glass-ceramics or the composition of the glass-ceramics used to prepare the strengthened glass-ceramics 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% or 2.76% in terms of mass percentage of oxide, or can be a value within a range defined by any two of the above specific values as endpoints, as long as a glass-ceramics or strengthened glass-ceramics 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-ceramics or strengthened glass-ceramics with desired properties of the present application can be obtained.

[0249] In the present application, Li20 helps to obtain higher compressive stress layer depth, increase Young's modulus and fracture toughness; at the same time, it can reduce the melting temperature and the temperature of crystal precipitation, but excessive addition of Li20 will lead to ceramming of the glass during annealing, or lead to precipitation of other phases affecting the transmittance of the glass-ceramics during heat treatment, or lead to excessive growth of crystals during heat treatment, resulting in a decrease in the transmittance of the obtained glass-ceramics. Too low addition of Li20 will lead to an increase in heat treatment temperature and a decrease in deep layer stress. In the present application, the mass percentage of Li20 in the composition at the center of the strengthened glass-ceramics or the composition of the glass-ceramics used to prepare the strengthened glass-ceramics or the composition of the base glass is 1.00% to 6.00%, preferably 1.00% to 4.00%, and more preferably 2.00% to 3.00%.

[0250] In some embodiments of the present application, the content of Li20 in the composition at the center of the strengthened glass-ceramics or the composition of the glass-ceramics used to prepare the strengthened glass-ceramics 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%, 2.35%, 1.55%, 1.50%, 1.77%, 1.60%, 1.62%, 2.28%, 2.27% or 2.24% in terms of mass percentage of oxide, or can be a value within a value range with any two of the above specific values as endpoints, as long as a glass-ceramics or 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 strengthened glass-ceramics with the desired properties of the present application can be obtained.

[0251] In the present application, K20 can be added as an optional component in an amount of 0-5.00% in terms of mass percentage, preferably 0-3.00%, more preferably 0-1.00%. In some embodiments, the composition at the center of the strengthened glass-ceramics or the composition of the glass-ceramics used to prepare the strengthened glass-ceramics or the composition of the base glass preferably does not contain K20.

[0252] 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, too much CaO will increase the density and CTE of the glass composition, significantly reducing the ion exchange performance of the glass-ceramics. In the present application, the mass percentage of CaO in the composition at the center of the strengthened glass-ceramics or the composition of the glass-ceramics used to prepare the strengthened glass-ceramics or the composition of the base glass is 0%-6.00%, preferably 0%-3.00%, more preferably 0%-1.50%.

[0253] In some embodiments of the present application, the content of CaO in the composition at the center 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 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%, or a value within a range defined by any two of the above specifically named 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 other range, as long as a glass-ceramic or strengthened glass-ceramic with the desired properties of the present application is obtained.

[0254] In the present application, B2O3 is an optional component. A proper 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 the heat treatment of the base glass to prepare the glass-ceramic, and can 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 at the center 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 is 0% to 10.00%, preferably 0% to 8.00%, and more preferably 0% to 4.00%.

[0255] In some embodiments of the present application, the content of B2O3 in the composition at the center 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 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%, 6.50%, 7.00%, 7.50%, 8.00%, 8.50%, 9.00%, 9.50%, 10.00%, or 7.07%, or a value within a range defined by any two of the above specifically named 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 other range, as long as a glass-ceramic or strengthened glass-ceramic with the desired properties of the present application is obtained.

[0256] In the present application, BaO is an optional component. Appropriate 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 ceramic. However, excessive 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 at the center of the strengthened glass ceramic or the composition of the glass ceramic used for preparing the strengthened glass ceramic or the composition of the base glass is 0% to 10.00%, preferably 0% to 7.00%, and more preferably 0% to 4.00%.

[0257] In some embodiments of the present application, the content of BaO in the composition at the center of the strengthened glass ceramic or the composition of the glass ceramic used for preparing 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%, 6.50%, 7.00%, 7.50%, 8.00%, 8.50%, 9.00%, 9.50%, 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 ceramic or a strengthened glass ceramic 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 ceramic or a strengthened glass ceramic with the required performance of the present application can be obtained.

[0258] In the present application, Y2O3 is an optional component. Y2O3 has the effect of making the glass structure compact. Appropriate amount of Y2O3 can increase the packing density inside the glass, which is manifested as increasing the density of the glass, thereby being beneficial to improve the intrinsic strength of the glass. For ion exchange performance, it can increase the stress effect of unit ion exchange of Li + + plasma in the chemical strengthening process, but may reduce the exchange speed. However, excessive Y2O3 is not conducive to obtaining transparent spinel glass ceramic. In the present application, the mass percentage of Y2O3 in the composition at the center of the strengthened glass ceramic or the composition of the glass ceramic used for preparing the strengthened glass ceramic or the composition of the base glass is 0% to 6.00%, preferably 0% to 4.00%, and more preferably 0% to 2.00%.

[0259] ​In some embodiments of the present application, the content of Y2O3 in the composition at the center of the strengthened glass-ceramics 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%, 1.52%, or 0.60%, or can be a value within a range defined by any two of the above specific numerical values as endpoints, as long as a glass-ceramics or 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 strengthened glass-ceramics with the desired properties of the present application can be obtained.

[0260] In the present application, La2O3 is an optional component, a network modifier component of the glass. An appropriate amount of La2O3 helps to increase the refractive index of the glass, reduce the high-temperature viscosity of the glass, and improve the glass melting effect and eliminate internal defects. At the same time, an appropriate amount of La2O3 can significantly improve the Young's modulus and micro Vickers hardness of the glass, and also has the effect of improving the chemical strengthening performance of the glass-ceramics and increasing the stress effect per ion exchange of the strengthened glass-ceramics. 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 at the center of the strengthened glass-ceramics or the composition of the glass-ceramics used to prepare the strengthened glass-ceramics or the composition of the base glass is 0% to 12.00%, preferably 0% to 5.00%, and more preferably 0% to 3.00%.

[0261] In some embodiments of the present application, the content of Y2O3 in the composition at the center of the strengthened glass-ceramics 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%, 1.52%, or 0.60%, or can be a value within a range defined by any two of the above specific numerical values as endpoints, as long as a glass-ceramics or 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 strengthened glass-ceramics with the desired properties of the present application can be obtained.

[0262] In the present application, on the basis of adjusting and controlling the content range of each oxide component, the content relationship of each oxide component is adjusted by adding an appropriate amount of Y2O3 and / or La2O3, which is beneficial to improve the strength, hardness, stability and deformation resistance of the strengthened glass ceramic.

[0263] In the present application, in order to obtain the strengthened glass ceramic with excellent performance as desired in the present application, in addition to Y2O3 and La2O3, metal oxides of cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium or scandium, 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 composition of the base glass, as long as the glass ceramic or the strengthened glass ceramic with the desired performance in the present application can be obtained. If the aforementioned metal oxides are added to the composition of the glass ceramic used for preparing the strengthened glass ceramic or the composition of the base glass, these metal oxides should also be contained in the composition at the center of the strengthened glass ceramic prepared.

[0264] In the present application, on the basis of adjusting and controlling the content range of each oxide component, the content relationship of each oxide component is adjusted and controlled, especially the mass percentage relationship between Na2O and Li2O and between Li2O and SiO2, which is beneficial to improve the intrinsic strength of the glass ceramic and the chemical strengthening effect, and further beneficial to obtain the strengthened glass ceramic with excellent mechanical strength performance.

[0265] In some embodiments of the present application, in the composition at the center of the strengthened glass ceramic or the composition of the glass ceramic used for preparing the strengthened glass ceramic or the composition of the base 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 0.90-5.00, and more preferably 1.00-3.00, in terms of mass percentage of oxides.

[0266] In some embodiments, the ratio of the mass percent of Na20 [Na20] to the mass percent of Li20 [Li20] [Na20] / [Li20] in the composition at the center of the strengthened glass-ceramic or in the composition of the glass-ceramic used to make the strengthened glass-ceramic or in the composition of the base glass 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 a range bounded by any two of the above specifically named values, as long as a glass-ceramic or strengthened glass-ceramic having the desired properties of the present application is obtained. It should 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.

[0267] In some embodiments of the present application, the mass percent of Li20 [Li20] to the mass percent of Si02 [Si02] in the composition at the center of the strengthened glass-ceramic or in the composition of the glass-ceramic used to make the strengthened glass-ceramic or in the composition of the base glass, in mass percent on an oxide basis, satisfies the following relationship: [Li20] / [Si02] = 0.03 to 0.20, preferably 0.04 to 0.15, more preferably 0.04 to 0.10.

[0268] In some embodiments, the ratio of the mass percent of Li20 [Li20] to the mass percent of Si02 [Si02] [Li20] / [Si02] in the composition at the center of the strengthened glass-ceramic or in the composition of the glass-ceramic used to make the strengthened glass-ceramic or in 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 bounded by any two of the above specifically named values, as long as a glass-ceramic or strengthened glass-ceramic having the desired properties of the present application is obtained. It should 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.

[0269] In this application, neither the zinc-magnesium spinel solid solution (Zn,Mg)Al2O4, the main crystalline phase, nor the tetragonal ZrO2 secondary crystalline phase contains alkali metal ions. Therefore, they do not participate in the ion exchange during the chemical strengthening process. Based on this, the crystal phase structure of the strengthened glass-ceramic obtained through chemical strengthening in this application is essentially 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 through chemical strengthening in this application are essentially the same as those of the glass-ceramic used for chemical strengthening in the preparation of this strengthened glass-ceramic. Figure 1 As shown, in Example 1, the XRD patterns of the glass-ceramic before and after chemical strengthening are basically the same. Additionally, as... Figure 2 As shown in this application, the transmittance of the glass ceramic before and after chemical strengthening is basically the same as that of the strengthened glass ceramic. In other words, in this application, by using glass ceramic with high transmittance, a strengthened glass ceramic product with the same excellent transmittance can be obtained through chemical strengthening treatment.

[0270] It should be understood that the stress structure generated by the chemical strengthening process can appropriately improve the mechanical properties of glass products. Therefore, in this application, after the glass ceramic is chemically strengthened to obtain strengthened glass ceramic glass, its mechanical properties such as Young's modulus and Vickers hardness will not decrease.

[0271] In this application, by ensuring that the glass-ceramic meets the desired total content / crystallinity of crystalline phases and an appropriate average crystal size, it is beneficial to enable the glass-ceramic to maintain excellent optical properties while satisfying excellent mechanical strength and high intrinsic strength.

[0272] In some embodiments of this application, the average crystal size of the strengthened glass-ceramic or the glass-ceramic used to prepare the strengthened glass-ceramic does not exceed 20 nm, preferably 1.0 nm to 10.0 nm, more preferably 4.0 nm to 9.0 nm, and even more preferably 4.0 nm to 8.0 nm. A suitable average crystal size / average grain size is beneficial for the glass-ceramic to possess both excellent optical properties and high intrinsic strength. However, if the average crystal size is too high, the glass-ceramic is prone to devitrification, and the chemical strengthening effect will also be affected. In this application, by ensuring that the glass-ceramic meets an appropriate average crystal size, it is beneficial to ensure that the glass-ceramic has excellent optical properties while obtaining good impact resistance and good compressive strength, and at the same time, it is beneficial to improve its chemical strengthening effect.

[0273] In some embodiments, the average crystallite size in the strengthened glass-ceramic or the glass-ceramic used to make 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, 6.8 nm, 6.4 nm, 6.5 nm, or 8.1 nm, or can be a value within a range defined by any two of the specifically named 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 other range, as long as a glass-ceramic or strengthened glass-ceramic having the desired properties of the present application is obtained.

[0274] In some embodiments of the present application, the total crystalline phase content in the strengthened glass-ceramic or the glass-ceramic used to make the strengthened glass-ceramic is 25% to 60%, preferably 30% to 55%, and more preferably 40% to 50% by mass. The higher the total crystalline phase content of the glass-ceramic or strengthened glass-ceramic, the more beneficial it is for the glass-ceramic or strengthened glass-ceramic to obtain high impact resistance and high compressive strength. However, if the total crystalline phase content is too high, it not only affects the chemical strengthening effect of the glass-ceramic, prolonging the chemical strengthening time for the glass-ceramic to obtain a strengthened glass-ceramic having a high stress level, but also can affect the optical properties of the glass-ceramic. In the present application, by having the glass-ceramic satisfy the desired total crystalline phase content, it is beneficial to allow the glass-ceramic to obtain good impact resistance and good compressive strength while ensuring that the glass-ceramic has excellent optical properties, and it is also beneficial to improve the chemical strengthening effect thereof.

[0275] In some embodiments, the total crystalline phase content of the strengthened glass-ceramic or the glass-ceramic used to make the strengthened glass-ceramic can be 30.00%, 30.50%, 31.00%, 31.50%, 32.00%, 32.50%, 33.00%, 33.50%, 34.00%, 34.50%, 35.00%, 35.50%, 36.00%, 36.50%, 37.00%, 37.50%, 38.00%, 38.50%, 39.00%, 39.50%, 40.00%, 40.50%, 41.00%, 41.50%, 42.00%, 42.50%, 43.00%, 43.50%, 44.00%, 44.50%, 45.00%, 45.50%, 46.00%, 46.50%, 47.00%, 47.50%, 48.00%, 48.50%, 49.00%, 49.50%, 50.00%, 48.69%, 45.11%, 49.52%, 47.85%, 54.07%, 51.56%, 45.49%, or 44.77%, or a value within a range having any two of the above specifically stated values as endpoints, as long as the glass-ceramic or strengthened glass-ceramic has the desired properties. It should be understood that any of the above ranges can be combined with any of the other ranges, as long as the glass-ceramic or strengthened glass-ceramic has the desired properties.

[0276] In some embodiments of the present application, the strengthened glass-ceramic or the glass-ceramic used to make the strengthened glass-ceramic is transparent in the visible wavelength range, preferably, the transmittance of the strengthened glass-ceramic or the glass-ceramic used to make the strengthened glass-ceramic is > 85.00% for 550 nm wavelength light at a thickness of 0.90 mm, preferably, the transmittance is > 87.00%. The glass-ceramic or strengthened glass-ceramic meeting this transmittance can ensure better light transmittance, better transparency, and is suitable for use in display screens that require display effects. The "visible wavelength range" herein refers to light having a wavelength of 360 nm to 740 nm.

[0277] In some embodiments, the strengthened glass-ceramic or the glass-ceramic used to make the strengthened glass-ceramic can have a transmittance of 86.00%, 86.50%, 87.00%, 87.50%, 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%, or 89.14%, or a value within a range having any two of these specifically endpoints, for a 550 nm wavelength light at a thickness of 0.90 mm. 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 application is obtained.

[0278] In the present application, by having the strengthened glass-ceramic with high Vickers hardness and fracture toughness, the strengthened glass-ceramic is less likely to break when subjected to extrusion or impact, which is beneficial to improving the compression resistance and impact resistance of the strengthened glass-ceramic. By having the strengthened glass-ceramic satisfy the appropriate stress structure, it is beneficial to exert the improvement effect of the stress structure on the mechanical strength performance, especially the excellent compression resistance and impact resistance to be achieved in the present application.

[0279] In some embodiments of the present application, 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 . The Vickers hardness of the strengthened glass-ceramic in the above range indicates that the strengthened glass-ceramic has high hardness and high intrinsic strength, thereby ensuring excellent mechanical properties.

[0280] In some embodiments, the Vickers hardness of the strengthened glass-ceramic can be 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 , 830 kgf / mm 2, 835 kgf / mm 2 , 840 kgf / mm 2 , 845 kgf / mm 2 , 855 kgf / mm 2 , 860 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 , 858 kgf / mm 2 , 875 kgf / mm 2 , 915 kgf / mm 2 , 850 kgf / mm 2 , 837 kgf / mm 2 , 900 kgf / mm 2 , 869 kgf / mm 2 , 889 kgf / mm 2 , 857 kgf / mm 2 , 865 kgf / mm 2 or 825 kgf / mm 2 , or can be a value within a range of values between any two of the above-mentioned specific numerical 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 of the other ranges, as long as the strengthened glass-ceramic has the desired properties.

[0281] In some embodiments of the present application, 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 . The fracture toughness value of the strengthened glass-ceramic is within the above-mentioned range, so that the strengthened glass-ceramic is less likely to break when subjected to a crush or impact, thereby facilitating the achievement of excellent crush resistance and excellent impact resistance.

[0282] In some embodiments, the fracture toughness value of the strengthened glass-ceramic can be 1.50 MPa-m 0.5 , 1.60 MPa-m 0.5 , 1.70 MPa-m 0.5 , 1.80 MPa-m 0.51.85 MPa·m 0.5 1.90 MPa·m 0.5 1.95 MPa·m 0.5 2.00 MPa·m 0.5 1.67 MPa·m 0.5 1.69 MPa·m 0.5 1.75 MPa·m 0.5 1.65 MPa·m 0.5 1.94 MPa·m 0.5 1.73 MPa·m 0.5 1.68 MPa·m 0.5 1.71 MPa·m 0.5 Or 1.77 MPa·m 0.5 Alternatively, the value can be any value within a range defined by any two of the above specific values ​​as endpoints, as long as it yields the reinforced glass-ceramic with the performance required by this application. It should be understood that, in specific embodiments, any of the above ranges can be combined with any other range, as long as it yields the reinforced glass-ceramic with the performance required by this application.

[0283] In some embodiments of this application, the reinforced glass ceramic has a |CT_AV| greater than 20.00 MPa, where |CT_AV| is the absolute value of the average tensile stress, measured by SLP_2000. Preferably, the reinforced glass ceramic has a |CT_AV| of 30.00 MPa to 55.00 MPa.

[0284] In some embodiments, the strengthened glass-ceramics can have a |CT AV| of 20.00 MPa, 22.00 MPa, 24.00 MPa, 26.00 MPa, 28.00 MPa, 30.00 MPa, 32.00 MPa, 34.00 MPa, 36.00 MPa, 38.00 MPa, 40.00 MPa, 42.00 MPa, 44.00 MPa, 46.00 MPa, 48.00 MPa, 50.00 MPa, 52.00 MPa, 54.00 MPa, 56.00 MPa, 58.00 MPa, 60.00 MPa, 50.96 MPa, 41.74 MPa, 36.56 MPa, 45.01 MPa, 41.49 MPa, 40.48 MPa, 50.27 MPa, 49.49 MPa, 36.05 MPa, 45.43 MPa, 53.86 MPa, 40.86 MPa, or 35.91 MPa, or a value within a range having any two of the above specifically stated values as endpoints, as long as a strengthened glass-ceramic having the desired properties herein is obtained. It should be understood that any of the above ranges can be combined with any of the other ranges, as long as a strengthened glass-ceramic having the desired properties herein is obtained.

[0285] In some embodiments of the present application, the strengthened glass-ceramics have a |CT CV| greater than 25.00 MPa, |CT CV| being the absolute value of the maximum tensile stress, determined by SLP_2000, and preferably, the chemically strengthened glass-ceramics have a |CT CV| of 40.00 MPa to 75.00 MPa.

[0286] In some embodiments, the strengthened glass-ceramics can have a |CT_CV| of 25.00 MPa, 30.00 MPa, 35.00 MPa, 40.00 MPa, 45.00 MPa, 50.00 MPa, 55.00 MPa, 60.00 MPa, 65.00 MPa, 70.00 MPa, 75.00 MPa, 80.00 MPa, 85.00 MPa, 90.00 MPa, 95.00 MPa, 100.00 MPa, 65.70 MPa, 54.30 MPa, 46.07 MPa, 68.75 MPa, 53.70 MPa, 53.07 MPa, 66.96 MPa, 71.25 MPa, 42.73 MPa, 60.57 MPa, 81.79 MPa, 52.40 MPa, or 44.78 MPa, or a value within a range bounded by any two of the foregoing specific values, as appropriate to provide a strengthened glass-ceramic having the desired properties. It should be appreciated that any of the foregoing ranges can be combined with any other range, as appropriate to provide a strengthened glass-ceramic having the desired properties.

[0287] In some embodiments of the application, the strengthened glass-ceramics have a CS_50 greater than 100 MPa, where CS_50 is the compressive stress value at a depth of 50 μm from the major surface of the strengthened glass-ceramic, as measured by SLP_2000, and preferably, the strengthened glass-ceramics have a CS_50 of 140 MPa to 200 MPa.

[0288] In some embodiments, the strengthened glass-ceramics can have a CS_50 of 100.00 MPa, 105.00 MPa, 110.00 MPa, 115.00 MPa, 120.00 MPa, 125.00 MPa, 130.00 MPa, 135.00 MPa, 140.00 MPa, 145.00 MPa, 150.00 MPa, 155.00 MPa, 160.00 MPa, 165.00 MPa, 170.00 MPa, 175.00 MPa, 180.00 MPa, 185.00 MPa, 190.00 MPa, 195.00 MPa, 200.00 MPa, 205.00 MPa, 210.00 MPa, 215.00 MPa, 220.00 MPa, 225.00 MPa, 230.00 MPa, 235.00 MPa, 240.00 MPa, 199.69 MPa, 155.95 MPa, 146.48 MPa, 181.94 MPa, 181.35 MPa, 141.02 MPa, 188.73 MPa, 168.30 MPa, 188.13 MPa, 162.61 MPa, 177.13 MPa, 190.71 MPa, or 204.29 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 present 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 present application is obtained.

[0289] In some embodiments of the present application, the strengthened glass-ceramics have a CS_80 of greater than 50 MPa, where CS_80 is the compressive stress value at a depth of 80 μm from the major surface of the strengthened glass-ceramic, as measured by SLP_2000, and preferably, the strengthened glass-ceramics have a CS_80 of 100 MPa to 150 MPa.

[0290] In some embodiments, the strengthened glass-ceramics can have a CS_80 of 50.00 MPa, 55.00 MPa, 60.00 MPa, 65.00 MPa, 70.00 MPa, 75.00 MPa, 80.00 MPa, 85.00 MPa, 90.00 MPa, 95.00 MPa, 100.00 MPa, 105.00 MPa, 110.00 MPa, 115.00 MPa, 120.00 MPa, 125.00 MPa, 130.00 MPa, 135.00 MPa, 140.00 MPa, 145.00 MPa, 150.00 MPa, 155.00 MPa, 160.00 MPa, 165.00 MPa, 170.00 MPa, 175.00 MPa, 180.00 MPa, 185.00 MPa, 190.00 MPa, 195.00 MPa, 200.00 MPa, 142.01 MPa, 111.53 MPa, 100.86 MPa, 140.44 MPa, 130.30 MPa, 110.00 MPa, 140.99 MPa, 129.89 MPa, 119.54 MPa, 117.60 MPa, 130.38 MPa, 138.72 MPa, or 152.35 MPa, or a value within a range bounded by any two of the foregoing specific values, as appropriate to achieve the desired properties of the strengthened glass-ceramics. It should be appreciated that any of the foregoing ranges can be combined with any other range, as appropriate to achieve the desired properties of the strengthened glass-ceramics.

[0291] In some embodiments of the application, the strengthened glass-ceramics have a DOL_0 greater than 144 μm, where DOL_0 is the depth of compressive stress layer determined by SLP_2000, preferably, the strengthened glass-ceramics have a DOL_0 of 160 μm to 200 μm.

[0292] In some embodiments, the strengthened glass-ceramic can have a DOL_0 of 144 μιη, 150 μιη, 155 μιη, 160 μιη, 165 μιη, 170 μιη, 175 μιη, 180 μιη, 185 μιη, 190 μιη, 195 μιη, 200 μιη, 205 μιη, 210 μιη, 215 μιη, 220 μιη, 225 μιη, 230 μιη, 235 μιη, 240 μιη, 185.12 μιη, 185.63 μιη, 176.34 μιη, 185.81 μιη, 191.19 μιη, 192.04 μιη, 189.59 μιη, 199.08 μιη, 164.11 μιη, 187.76 μιη, 191.43 μιη, 197.80 μιη, or 215.20 μιη, or a value within a range bounded by any two of the foregoing specific values, as long as a strengthened glass-ceramic having the desired properties of the application is obtained. It will be appreciated that in specific embodiments, any of the foregoing ranges can be combined with any other range, as long as a strengthened glass-ceramic having the desired properties of the application is obtained.

[0293] In some embodiments of the application, the strengthened glass-ceramic has a DOL_0 > 0.16t, where DOL_0 is the depth of compressive stress layer measured by SLP_2000, and t is the thickness of the strengthened glass-ceramic, preferably DOL_0 > 0.18t, more preferably DOL_0 > 0.20t.

[0294] In some embodiments, the strengthened glass-ceramic can have a DOL_0 of 0.17t, 0.18t, 0.19t, 0.20t, 0.21t, 0.22t, 0.23t, 0.24t, or 0.25t, or a value within a range bounded by any two of the foregoing specific values, as long as a strengthened glass-ceramic having the desired properties of the application is obtained. It will be appreciated that in specific embodiments, any of the foregoing ranges can be combined with any other range, as long as a strengthened glass-ceramic having the desired properties of the application is obtained.

[0295] In some embodiments of the application, the single bar static pressure strength of the strengthened glass-ceramic is greater than 800 N, preferably greater than 850 N, measured by using a 10 mm diameter round head metal pressure rod to apply a load step by step vertically downward at a rate of 10 mm / min to the center of the major surface of the strengthened glass-ceramic having a thickness greater than 0.7 mm.

[0296] In some embodiments of the present application, the strengthened glass-ceramics having a thickness of greater than 0.7 mm are subjected to a 2.5 m drop test using 80 grit silicon carbide sandpaper. If the glass sample does not break after the drop, it is recorded as a pass. The pass rate of the strengthened glass-ceramics is greater than or equal to 50%, preferably greater than or equal to 60%, and more preferably greater than or equal to 70%. The pass rate is based on testing of at least 10 samples.

[0297] In some embodiments of the present application, the strengthened glass-ceramics having a thickness of greater than 0.7 mm are subjected to a drop ball impact test using a 130 g steel ball to test the central drop ball impact energy that the strengthened glass-ceramics can withstand. The central drop ball impact energy that the strengthened glass-ceramics can withstand is greater than 0.7 J, and preferably greater than 0.8 J.

[0298] In some embodiments of the present application, the glass-ceramics or strengthened glass-ceramics are 2D, 2.5D, 3D, or shaped. In some embodiments of the present application, the glass-ceramics or strengthened glass-ceramics are isometric or anisometric. One skilled in the art can select according to the needs. "Anisometric" means that the glass-ceramics or strengthened glass-ceramics contain at least two portions having different thicknesses.

[0299] After the foregoing describes the composition, crystal phase structure, and stress structure of the strengthened glass-ceramics, the preparation method of the strengthened glass-ceramics is described in detail below.

[0300] In the present application, the preparation process of the strengthened glass-ceramics mainly includes the preparation process of the glass-ceramics and the chemical strengthening process, and the preparation process of the glass-ceramics mainly includes the preparation process of the base glass and the heat treatment process of the base glass.

[0301] 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, a float method, an overflow method, a calendering process, or a casting process. Illustratively, the components are mixed according to the formula, melted and formed, and then subjected to cooling and annealing treatment, so as to obtain the base glass.

[0302] For example, the raw materials (industrial conventional raw materials) are proportioned according to the formula, a clarifying agent is added, and then the mixture is mixed for a period of time to obtain a raw material mixture with uniform mixing. The raw material mixture is placed in a platinum crucible, heated to 1450-1800°C, preferably the melting temperature is 1550-1680°C, and preferably the temperature is maintained for 3-12 hours, and then poured into a forming mold to cool and form, preferably cooled to 800-1000°C, and then placed in an annealing furnace for annealing treatment, preferably the annealing temperature is 500-700°C, and the annealing time is preferably 4-48 hours; then the furnace is cooled to room temperature, and the base glass is obtained. Those skilled in the art can select the type and amount of clarifying agent according to the needs, without the need for creative labor. Further, the clarifying agent can include, but is not limited to, one or more of sodium chloride, tin oxide, antimony oxide, or arsenic oxide, and the amount of clarifying agent added can be 0-1 wt% of the total amount of raw materials.

[0303] In some embodiments of the present application, the heat treatment process of the base glass can include nucleation treatment and / or crystallization treatment, preferably both nucleation treatment and crystallization treatment. In some embodiments, the crystallization treatment can include one-step crystallization treatment or multi-step crystallization treatment.

[0304] In some embodiments of the present application, in order to obtain the desired physical and chemical properties of the glass-ceramics, the base glass can be subjected to one-step heat treatment, two-step or multi-step heat treatment. If one-step heat treatment is performed, it means that the nucleation treatment (i.e., nucleation treatment) is not performed separately, and one-step temperature rising is directly performed, and the nucleation and target crystal growth are performed at the temperature reached in the one-step temperature rising process, which can be understood as directly performing crystallization treatment. If two-step heat treatment is performed, it means that two-step temperature rising process is performed, and nucleation treatment (i.e., nucleation treatment) is performed first, and then target crystal growth treatment (i.e., crystallization treatment) is performed.

[0305] In the present application, in order to obtain the desired crystal phase of the glass-ceramics and the desired physical and chemical properties, further, the nucleation treatment temperature can be 600-850°C, the nucleation treatment time can be 0-72h, preferably 0-10h; the crystallization treatment temperature can be 700-1000°C, and the crystallization treatment time can be 0.10-24h, preferably 0.1-6h. When heat treatment is performed, the temperature rising rate is preferably controlled to be 5-15°C / min, more preferably the temperature rising rate is 10°C / min. The nucleation treatment temperature refers to the temperature at which crystal nuclei can form. The crystallization treatment temperature refers to the temperature at which the target crystal can grow controllably.

[0306] After the heat treatment, the skilled person can also perform other conventional steps to obtain a glass-ceramic sample that meets the required specifications or requirements, for example, it is possible to perform a shaping treatment, a cutting treatment (for example using a multi-wire saw), a CNC machining treatment (computer numerical control), a thinning treatment or a polishing treatment, among others.

[0307] In some embodiments of the present application, the glass-ceramic described above is subjected to a specific chemical strengthening treatment, which allows obtaining a strengthened glass-ceramic that meets the desired properties.

[0308] 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, thus forming a compressive stress layer on the surface of the glass-ceramic and obtaining a strengthened glass-ceramic with better mechanical properties.

[0309] In some embodiments of the present application, the chemical strengthening treatment can be performed using a single-step strengthening method or a multi-step strengthening method. The molten salt bath used for the chemical strengthening treatment is a molten salt bath containing sodium and / or potassium salts. Preferably, in the present application, the chemical strengthening is performed using a two-step strengthening method, preferably the salt bath used for the first step of the strengthening ion exchange is a pure NaNO3salt bath, in which the Na + with the Li + ions in the glass-ceramic are exchanged, so as to obtain a high stress layer depth DOL_0and a high deep stress. Preferably, the salt bath used for the second step of the strengthening ion exchange is a pure KNO3salt bath, in which the K + with the Na + ions in the glass-ceramic are exchanged, so that the Na + ions in the glass-ceramic, as far as possible, are exchanged for K + ions, so as to obtain a high surface compressive stress level. When performing the second step of the strengthening ion exchange, the K +The relative atomic mass of potassium is large, and stress relaxation is prone to occur, so the diffusion depth and distribution of potassium ions need to be strictly controlled. Meanwhile, the deep stress formed in the first step of strengthening ion exchange may decrease during the second step of ion exchange. That is, when high surface compressive stress is formed in the second step of strengthening ion exchange, deep stress may decrease, which is not conducive to improving the impact resistance (e.g., drop impact resistance) of the strengthened glass ceramic. Therefore, the distribution of sodium ions and the deep stress structure also need to be strictly controlled in the second step of strengthening ion exchange. The temperature of the molten salt bath is preferably 380-600°C, and 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 chemical strengthening treatment time is preferably 0.1-48h, and more preferably 0.1-24h. The sodium salt can be selected from at least one of sodium nitrate, sodium sulfate, and sodium carbonate, and is preferably sodium nitrate; the potassium salt can be selected from at least one of potassium nitrate, potassium sulfate, and potassium carbonate, and is preferably potassium nitrate; and the lithium salt can be selected from at least one of lithium nitrate, lithium sulfate, and lithium carbonate, and is preferably lithium nitrate.

[0310] In some embodiments of the present application, 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 In some embodiments of the present application, 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 In some embodiments of the present application, 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 In some embodiments of the present application, 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

[0311] In the present application, at least two steps of ion exchange are used for strengthening to make the prepared strengthened glass ceramic meet a specific stress structure. This is conducive to making the prepared strengthened glass ceramic simultaneously have excellent extrusion resistance and excellent impact resistance (e.g., excellent drop impact resistance).

[0312] Without being bound by any theory, in the first step of the strengthening process, the main purpose is to form a specific deep stress structure, so as to effectively inhibit or hinder the crack propagation caused by drop impact and the like. As the ions diffuse into the glass-ceramic, the deep stress will gradually decrease. Therefore, in the first step of the strengthening process, the purpose is to obtain a high stress depth of layer DOL_0 and a high deep stress, so as to make the strengthened glass-ceramic meet the specific deep stress structure. At this time, in combination with the second step of the chemical strengthening process, the strengthened glass-ceramic meets the specific surface stress structure, and the surface compressive stress level of the strengthened glass-ceramic is improved. Finally, by making the strengthened glass-ceramic meet the specific deep stress structure and the specific surface stress structure, the strengthened glass-ceramic obtains a specific stress structure, and at the same time, the improvement of the extrusion resistance and the impact resistance of the strengthened glass-ceramic is realized, so that the strengthened glass-ceramic can simultaneously have excellent extrusion resistance and excellent impact resistance.

[0313] The glass-ceramic or the strengthened glass-ceramic provided by the present application has excellent performance (especially excellent extrusion resistance and excellent impact resistance), and 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 central control, electronic whiteboard glass, smart home, smart wear (such as smart bracelet, smart watch, smart glasses), and can also be used in vehicles, aircraft or ships, and can also be used in any required glass-ceramic or strengthened glass-ceramic glass device. 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 ship, 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.

[0314] For example, the glass-ceramic or the strengthened glass-ceramic provided by the present application has excellent performance, and can be used to manufacture glass devices. The glass devices referred to herein can be regular or irregular, and those skilled in the art can manufacture them according to requirements.

[0315] For example, the glass-ceramic or the strengthened glass-ceramic provided by the present application has excellent performance, and can be used to manufacture cover glass. The cover glass can be a display screen cover, back cover or camera protection cover of an electronic device. For example, the glass-ceramic or the strengthened glass-ceramic provided by the present application has excellent performance, and can be used in electronic devices. For reference Figure 9 、 Figure 10 、 Figure 11 and Figure 12In some embodiments of the present application, an electronic device, which can be a mobile phone, a tablet computer, a smart wearable device, or the like, is provided. The electronic device includes a housing 1 assembled on the outer side of the electronic device. The housing 1 includes 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. In some embodiments of the present application, the display screen cover plate 11 and / or the back cover 12 are made of the aforementioned glass ceramic or strengthened glass ceramic. In some embodiments of the present application, the display screen cover plate 11 and the back cover 12 can be made of the aforementioned glass ceramic or strengthened glass ceramic entirely or partially.

[0316] In some embodiments of the present application, as shown in FIG. 1, the electronic device further includes a camera assembly 2 located inside the housing 1. The housing 1 can include 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 ceramic or strengthened glass ceramic. Figure 10 In some embodiments of the present application, as shown in FIG. 1, the electronic device further includes a camera assembly 2 located inside the housing 1. The housing 1 can include 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 ceramic or strengthened glass ceramic.

[0317] In some embodiments of the present application, as shown in FIG. 1, the electronic device further includes a camera assembly 2 located inside the housing 1. The housing 1 can include 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 ceramic or strengthened glass ceramic. Figure 11 In some embodiments of the present application, as shown in FIG. 1, the electronic device further includes a camera assembly 2 located inside the housing 1. The housing 1 can include 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 ceramic or strengthened glass ceramic.

[0318] In some embodiments of the present application, the display screen cover plate, the back cover, the camera protection cover plate, and the middle frame of the electronic device can be made of the aforementioned glass ceramic or strengthened glass ceramic.

[0319] In some embodiments of the present application, the display screen cover plate, back cover, camera protection cover plate or 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, back cover, camera protection cover plate or middle frame in the electronic device can be of equal thickness or unequal thickness.

[0320] 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.

[0321] Embodiment 1

[0322] A strengthened glass ceramic is prepared as follows:

[0323] (1) Preparation of base material glass:

[0324] 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 the V-shaped mixer is used for mixing for 30 minutes to obtain a raw material mixture with uniform mixing.

[0325] The raw material mixture is transferred to a platinum crucible, then melted in the platinum crucible at 1650℃ for 5 hours, then poured into a forming mold for cooling, cooled to 900℃, then placed in a 600℃ annealing furnace for annealing for 24 hours, then cooled to room temperature with the furnace, and the base material glass brick is obtained.

[0326] (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, then heated to 765℃ at a rate of 10℃ / min for crystallization treatment, 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 the details are shown in Table 1.

[0327] After the obtained glass-ceramic sample bricks are subjected to cutting, CNC processing (the CNC instrument used in the present application is of RCG500S type), and polishing, cold processing, glass-ceramic samples meeting the required specifications and requirements can be prepared. In Examples 1-13 and Comparative Examples 1-13 of the present application, the glass-ceramic sample bricks are subjected to the aforementioned cold processing to prepare glass-ceramic samples with thicknesses of 0.70 mm, 0.90 mm, 0.95 mm, or 1.05 mm. Specifically, circular glass-ceramic polished pieces with a diameter of 46 mm and thicknesses of 0.70 mm, 0.90 mm, 0.95 mm, or 1.05 mm are prepared.

[0328] Test conditions for the glass-ceramic samples / pieces obtained in Example 1:

[0329] The crystal phase composition, average crystal size, total content of crystal phase, transmittance (under 550 nm wavelength light), density, Vickers hardness, and fracture toughness of the glass-ceramic samples / pieces are tested, respectively, and the results are shown in Table 2.

[0330] (3) Preparation of strengthened glass-ceramic: The obtained glass-ceramic samples / pieces are placed in a strengthening furnace cavity for preheating for 5 min according to the chemical strengthening process in Table 3, and then quickly placed in a 450℃ molten salt bath for first-step strengthening treatment. The composition of the molten salt is 100wt% NaNO3, and the chemical strengthening treatment time is 4 h. Then, the glass-ceramic samples / pieces are placed in a 420℃ molten salt bath for second-step strengthening treatment. The composition of the molten salt is 100wt% KNO3, and the chemical strengthening treatment time is 4 h. After that, the glass-ceramic samples / pieces 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, and the glass-ceramic samples are dried to obtain strengthened glass-ceramic.

[0331] Test conditions for the strengthened glass-ceramic samples / pieces obtained in Example 1:

[0332] I. The surface Na2O mass percentage and surface K2O mass percentage of the strengthened glass-ceramic after the first-step strengthening treatment and the second-step strengthening treatment are determined by XRF, and the results are shown in Table 3.

[0333] II. The CS_50, CS_80, DOL_0, |CT_CV|, and |CT_AV| of the strengthened glass-ceramic are measured under SLP-2000 stress instrument (the light source wavelength 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 value of formula A is calculated, and the absolute value K of the average slope at different depth segments is calculated according to the SLP stress distribution curve. 50-80 , K80-DOL The results are shown in Table 4.

[0334] III, The strengthened glass ceramic is subjected to micro-area composition analysis by using Shimadzu electron probe EPMA-1720HT to generate characteristic X-rays after the sample is subjected to electron beam, and DOL_K and DOL_Na are measured, and P1, P2, P3 and P4 are calculated according to the absolute value of the average slope of different depth segments calculated from the K element concentration distribution curve and the Na element concentration distribution curve. 5-8 The results are shown in Table 3-Table 4.

[0335] IV, the single rod static pressure strength, the center ball impact energy that the strengthened glass ceramic can withstand, the passing rate of the strengthened glass ceramic in the 80-mesh sandpaper, 2.5m height drop test, and the Vickers hardness and fracture toughness of the strengthened glass ceramic are tested, and the results are shown in Table 4.

[0336] Examples 2-13

[0337] 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 Table 1-Table 4.

[0338] The XRD pattern comparison chart of the glass ceramic and the strengthened glass ceramic of Example 1 is shown in Figure 1 From the chart, it can be seen that ① the main crystal phase of the glass ceramic and the strengthened glass ceramic is (Zn, Mg) Al2O4, and the secondary crystal phase is ZrO2; ② the XRD patterns of the glass ceramic and the strengthened glass ceramic are basically coincident, indicating that the crystal structure is basically unchanged before and after chemical strengthening.

[0339] The transmittance curve comparison chart of the glass ceramic and the strengthened glass ceramic of Example 1 is shown in Figure 2 From the chart, it can be seen that the glass ceramic and the strengthened glass ceramic prepared therefrom are both transparent in the visible light range, both have high transmittance, and the transmittance remains basically unchanged before and after chemical strengthening.

[0340] Comparative Examples 1-13

[0341] 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 Table 1-Table 4.

[0342]

[0343]

[0344]

[0345]

[0346]

[0347]

[0348] From the above examples and comparative examples of Table 1-Table 4, it can be seen that the embodiments of the present application use zinc-aluminum spinel-magnesium-aluminum spinel solid solution as the main crystal phase of the glass-ceramics, so that the glass-ceramics has high intrinsic strength, high Vickers hardness and high fracture toughness. By chemical strengthening of the glass-ceramics, and by meeting the specific requirements of the surface composition and stress distribution of the strengthened glass-ceramics, especially the surface Na2O content, surface K2O content, K + diffusion depth, Na + concentration maximum position depth meet the specific requirements, and the thickness, K + diffusion depth (or K + exchange (layer) depth DOL_K, |CT-AV| and the compressive stress layer depth DOL_0 meet the requirements of formula A, which significantly improves the mechanical properties of the strengthened glass-ceramics, and the strengthened glass-ceramics simultaneously obtains excellent extrusion resistance and impact resistance.

[0349] In the schemes of Comparative Example 1 to Comparative Example 13, the composition of the glass-ceramics used to prepare the strengthened glass-ceramics, the surface composition or stress distribution of the prepared strengthened glass-ceramics do not meet the specific requirements of the present application, which ultimately leads to the fact that the extrusion resistance and / or impact resistance of the prepared strengthened glass-ceramics is significantly worse than the embodiments that meet the requirements of the present application.

[0350] Some comparative examples are analyzed as follows:

[0351] The base glass composition of Comparative Example 1 does not contain Li2O, which does not meet the composition requirements of the present application at the center of the strengthened glass-ceramics. After heat treatment, the Vickers hardness of the prepared glass-ceramics is 650 kgf / mm 2 , and the fracture toughness value is 1.32 MPa·m 0.5 . After chemical strengthening treatment of the glass-ceramics, although DOL_K, surface K2O concentration, DOL_Na and relationship formula A do not meet the requirements of the present application for the strengthened glass-ceramics. Finally, through testing, the single rod static pressure strength that the strengthened glass-ceramics can withstand is only 605 N, it cannot pass the 80 mesh sandpaper-2.5 m drop test, and the ball impact test also breaks at the initial height. The impact resistance and pressure resistance of the strengthened glass-ceramics are significantly lower than the embodiments of the present application.

[0352] The Na2O content in the base glass composition of Comparative Example 2 is 0.87%, which is too low to meet the composition requirement at the center of the strengthened glass ceramic according to 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 treatment of the glass ceramic, the DOL_Na in the strengthened glass ceramic prepared does not meet the requirement of the strengthened glass ceramic according to the present application. Finally, the single rod static pressure strength that the strengthened glass ceramic can withstand is only 558 N, and the drop ball impact test also breaks at the initial height, and the impact resistance and compression resistance of the strengthened glass ceramic are obviously lower than the embodiment scheme of the present application.

[0353] The Li2O concentration in the base glass composition of Comparative Example 3 is 0.79%, which is too low to meet the composition requirement at the center of the strengthened glass ceramic according to 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 treatment of the glass ceramic, the relationship A in the strengthened glass ceramic prepared does not meet the requirement of the strengthened glass ceramic according to the present application. Finally, the single rod static pressure strength that the strengthened glass ceramic can withstand is only 690 N, and the drop ball impact test also breaks at the initial height, and the impact resistance and compression resistance of the strengthened glass ceramic are obviously lower than the embodiment scheme of the present application.

[0354] Comparative Examples 4 to 13 are obtained by using the glass ceramic of Example 1 under different thicknesses and different strengthening conditions, but the surface composition and stress distribution of the strengthened glass ceramic prepared in Comparative Examples 4 to 13, especially the surface Na2O content, the surface K2O content, the K + diffusion depth, the depth of the position of the maximum Na + concentration, and the relationship A, cannot simultaneously meet the requirement of the strengthened glass ceramic according to the present application. Finally, the strengthened glass ceramic prepared in Comparative Examples 4 to 13 either has a single rod static pressure strength lower than 800 N, or has a 80-mesh sandpaper-2.5 m drop test passing rate less than 50%, or has a center drop ball impact energy lower than 0.7 J, and the impact resistance and compression resistance of the strengthened glass ceramic are obviously lower than the embodiment scheme of the present application.

[0355] The above only describes specific embodiments 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 modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A strengthened glass-ceramic, characterized in that, The composition of the center of the strengthened glass ceramic or the tensile stress layer comprises, in mass percent 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%; The strengthened glass ceramic comprises a main crystal phase of a zinc aluminum spinel-magnesium aluminum spinel solid solution and a secondary crystal phase of zirconium oxide; the strengthened glass ceramic has a compressive stress layer on the surface and a tensile stress in the interior; The surface K2O mass percent of the strengthened glass ceramic is 2.50% to 7.50% in mass percent of oxides; The surface Na2O mass percent of the strengthened glass ceramic is less than or equal to 0.010% in mass percent of oxides; The strengthened glass-ceramic satisfies: 8.00 pm < DOL_K < 20.00 pm, wherein DOL_K is the K + diffusion depth; The strengthened glass ceramic satisfies: 30.00 pm ≤ DOL_Na ≤ 60.00 pm, wherein DOL_Na is the distance from the main surface of the strengthened glass ceramic to Na + depth of the location of the maximum concentration; The strengthened glass ceramic satisfies: A = (t x DOL_K) / (|CT-AV| x (DOL_0 / t)), 850 <= A <= 4000; wherein, t is the thickness of the strengthened glass ceramic, in units of pm; DOL_K is the K + diffusion depth, in units of pm; |CT-AV| is the absolute value of the average tensile stress of the strengthened glass ceramic, in units of MPa; DOL_0 is the depth of the compressive stress layer of the strengthened glass ceramic, in units of pm; in the formula A, the data is substituted into the formula according to the above unit requirements, and a calculation result is obtained.

2. The strengthened glass ceramic of claim 1, wherein, The surface K2O mass percent of the strengthened glass ceramic is 3.00% to 7.00% in mass percent of oxides; and / or, The surface Na2O mass percent of the strengthened glass ceramic is less than or equal to 0.005% in mass percent of oxides; and / or, The strengthened glass-ceramic satisfies: 8.50 pm < DOL_K < 18.00 pm, where DOL_K is the K + diffusion depth; and / or, The strengthened glass-ceramic satisfies: 34.00 pm ≤ DOL_Na ≤ 59.00 pm, wherein DOL_Na is the distance from the main surface of the strengthened glass-ceramic to Na + the depth of the location of the maximum concentration; The strengthened glass ceramic satisfies: 850≤A≤3000.

3. The strengthened glass ceramic of claim 2, wherein, The surface K2O mass percent of the strengthened glass ceramic is 3.50% to 7.00% in mass percent of oxides; and / or, The surface Na2O mass percent of the strengthened glass ceramic is less than or equal to 0.002% in mass percent of oxides; and / or, The strengthened glass-ceramic satisfies: 9.00 pm < DOL_K < 16.00 pm, where DOL_K is the K + diffusion depth; and / or, The strengthened glass-ceramic satisfies: 37.00 pm ≤ DOL_Na ≤ 59.00 pm, wherein DOL_Na is the Na + depth of the location of the maximum concentration; and / or, The strengthened glass ceramic satisfies: 900≤A≤2000.

4. 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; and / or, The concentration of Na + increases nonlinearly from the main surface of the strengthened glass ceramic to the center of the strengthened glass ceramic and then decreases nonlinearly along the thickness direction of the strengthened glass ceramic.

5. The strengthened glass ceramic of claim 1, wherein, The strengthened glass ceramic satisfies: In a K element concentration distribution curve with the horizontal axis being a depth in μm from the main surface of the strengthened glass ceramic and the vertical axis being a K element concentration in mass percent on an element basis: The absolute value P1 of the average slope of the K element concentration distribution curve between the depth of 0 μm and the depth of DOL_K is 0.150 to 1.000; and / or, The absolute value P of the average slope of the K element concentration profile between the depth of 5 μm and the depth of 8 μm 5-8 is 0.50 to 2.50; and / or, In a Na element concentration distribution curve with the horizontal axis being a depth in μm from the main surface of the strengthened glass ceramic and the vertical axis being a Na element concentration in mass percent on an element basis: The absolute value P2 of the average slope of the Na element concentration distribution curve between the depth of 0 μm and the depth of DOL_Na is 0.01 to 0.

05.

6. The strengthened glass ceramic of claim 5, wherein, The strengthened glass ceramic satisfies: In a K element concentration distribution curve with the horizontal axis being a depth in μm from the main surface of the strengthened glass ceramic and the vertical axis being a K element concentration in mass percent on an element basis: An absolute value P1 of an average slope of the K element concentration distribution curve between a depth of 0 micrometers and a depth of DOL_K is 0.150 to 0.800; and / or, The absolute value P of the average slope of the K element concentration profile between the depth of 5 μm and the depth of 8 μm 5-8 0.60 to 2.00; and / or, In a Na element concentration distribution curve in which a horizontal axis is a depth in micrometers from a main surface of the strengthened glass ceramic, and a vertical axis is a Na element concentration in mass percent on an element basis: An absolute value P2 of an average slope of the Na element concentration distribution curve between a depth of 0 micrometers and a depth of DOL_Na is 0.01 to 0.

04.

7. The strengthened glass ceramic of claim 6, wherein, The strengthened glass ceramic satisfies: In a K element concentration distribution curve in which a horizontal axis is a depth in micrometers from a main surface of the strengthened glass ceramic, and a vertical axis is a K element concentration in mass percent on an element basis: An absolute value P1 of an average slope of the K element concentration distribution curve between a depth of 0 micrometers and a depth of DOL_K is 0.150 to 0.600; and / or, The absolute value P of the average slope of the K element concentration profile between the depth of 5 μm and the depth of 8 μm 5-8 is 0.70 to 1.50; and / or, In a Na element concentration distribution curve in which a horizontal axis is a depth in micrometers from a main surface of the strengthened glass ceramic, and a vertical axis is a Na element concentration in mass percent on an element basis: An absolute value P2 of an average slope of the Na element concentration distribution curve between a depth of 0 micrometers and a depth of DOL_Na is 0.01 to 0.

03.

8. The strengthened glass ceramic of claim 4, wherein, The strengthened glass ceramic satisfies: In a K element concentration distribution curve in which a horizontal axis is a depth in micrometers from a main surface of the strengthened glass ceramic, and a vertical axis is a K element concentration in mass percent on an element basis: An absolute value P1 of an average slope of the K element concentration distribution curve between a depth of 0 micrometers and a depth of DOL_K is 0.150 to 1.000; and / or, The absolute value P of the average slope of the K element concentration profile between the depth of 5 μm and the depth of 8 μm 5-8 is 0.50 to 2.50; and / or, In a Na element concentration distribution curve in which a horizontal axis is a depth in micrometers from a main surface of the strengthened glass ceramic, and a vertical axis is a Na element concentration in mass percent on an element basis: An absolute value P2 of an average slope of the Na element concentration distribution curve between a depth of 0 micrometers and a depth of DOL_Na is 0.01 to 0.

05.

9. The strengthened glass ceramic of claim 1, wherein, The strengthened glass ceramic satisfies: In an SLP stress distribution curve in which a horizontal axis is a depth in micrometers from a main surface of the strengthened glass ceramic, and a vertical axis is a stress in MPa: The absolute value K of the average slope of the SLP stress profile between the depth of 50 μm and the depth of 80 μm 50-80 is 1.00 to 2.50; and / or, The absolute value K of the average slope of the SLP stress profile between the depth of 80 μm and the depth of DOL_0 80-DOL-0 is 0.90 to 2.

00.

10. The strengthened glass ceramic of claim 9, wherein, The strengthened glass ceramic satisfies: In an SLP stress distribution curve in which a horizontal axis is a depth in micrometers from a main surface of the strengthened glass ceramic, and a vertical axis is a stress in MPa: The absolute value K of the average slope of the SLP stress profile between the depth of 50 μm and the depth of 80 μm 50-80 is 1.00 to 2.40; and / or, The absolute value K of the average slope of the SLP stress profile between the depth of 80 pm and the depth of DOL_0 80-DOL-0 is 0.90 to 1.

80.

11. The strengthened glass ceramic of claim 10, wherein, The strengthened glass ceramic satisfies: In an SLP stress distribution curve in which a horizontal axis is a depth in micrometers from a main surface of the strengthened glass ceramic, and a vertical axis is a stress in MPa: The absolute value K of the average slope of the SLP stress profile between the depth of 50 μm and the depth of 80 μm 50-80 is 1.00 to 2.30; and / or, The absolute value K of the average slope of the SLP stress profile between the depth of 80 pm and the depth of DOL_0 80-DOL-0 is 0.90 to 1.

60.

12. The strengthened glass ceramic of claim 8, wherein, The strengthened glass ceramic satisfies: In an SLP stress distribution curve in which a horizontal axis is a depth in micrometers from a main surface of the strengthened glass ceramic, and a vertical axis is a stress in MPa: The absolute value K of the average slope of the SLP stress profile between the depth of 50 μm and the depth of 80 μm 50-80 is 1.00 to 2.50; and / or, The absolute value K of the average slope of the SLP stress profile between the depth of 80 μm and the depth of DOL_0 80-DOL-0 is 0.90 to 2.

00.

13. The strengthened glass ceramic of claim 1, wherein The strengthened glass ceramic satisfies: In an SLP stress distribution curve in which a horizontal axis is a depth in micrometers from a main surface of the strengthened glass ceramic, and a vertical axis is a stress in MPa: The strengthened glass ceramic has a thickness t of greater than 0.7 mm; and / or, The strengthened glass ceramic is 2D, 2.5D, 3D or profiled; and / or, The strengthened glass ceramic is equal-thickness or unequal-thickness.

14. The strengthened glass ceramic of claim 13, wherein, The thickness t of the strengthened glass ceramic is not less than 0.8 mm.

15. The strengthened glass ceramic of claim 14, wherein, The thickness t of the strengthened glass ceramic is 0.9 mm to 2.0 mm.

16. The strengthened glass ceramic of any one of claims 1 to 15, wherein, The mass percentage of Na2O [Na2O] and the mass percentage of Li2O [Li2O] in the composition at the center of the strengthened glass ceramic or the tensile stress layer satisfy the following relationship: [Na2O] / [Li2O]=0.60 to 6.00; and / or, The mass percentage of Li2O [Li2O] and the mass percentage of SiO2 [SiO2] in the composition at the center of the strengthened glass ceramic or the tensile stress layer satisfy the following relationship: [Li2O] / [SiO2]=0.03 to 0.

20.

17. The strengthened glass ceramic of claim 16, wherein, The mass percentage of Na2O [Na2O] and the mass percentage of Li2O [Li2O] in the composition at the center of the strengthened glass ceramic or the tensile stress layer satisfy the following relationship: [Na2O] / [Li2O]=0.90 to 5.00; and / or, The mass percentage of Li2O [Li2O] and the mass percentage of SiO2 [SiO2] in the composition at the center of the strengthened glass ceramic or the tensile stress layer satisfy the following relationship: [Li2O] / [SiO2]=0.04 to 0.

15.

18. The strengthened glass ceramic of claim 17, wherein, The mass percentage of Na2O [Na2O] and the mass percentage of Li2O [Li2O] in the composition at the center of the strengthened glass ceramic or the tensile stress layer satisfy the following relationship: [Na2O] / [Li2O]=1.00 to 3.00; and / or, The mass percentage of Li2O [Li2O] and the mass percentage of SiO2 [SiO2] in the composition at the center of the strengthened glass ceramic or the tensile stress layer satisfy the following relationship: [Li2O] / [SiO2]=0.04 to 0.

10.

19. The strengthened glass ceramic of claim 1, wherein, The composition at the center of the strengthened glass ceramic or the tensile stress layer comprises, in terms of mass percentage of oxides: The mass percentage of SiO2 is 30.00% to 42.00%; and / or, The mass percentage of Al2O3 is 32.00% to 42.00%; and / or, The mass percentage of ZrO2 is 4.00% to 7.00%; and / or, The mass percentage of MgO is 2.50% to 4.00%; and / or, The mass percentage of ZnO is 9.00% to 13.00%; and / or, The mass percentage of Na2O is 1.00% to 8.00%; and / or, The mass percentage of K2O is 0% to 3.00%; and / or, The mass percentage of Li2O is 1.00% to 4.00%; and / or, The mass percentage of CaO is 0% to 3.00%; and / or, The mass percentage of B2O3 is 0% to 8.00%; and / or, The mass percentage of BaO is 0% to 7.00%; and / or, Y2O3 is 0% to 4.00% by mass; and / or, La2O3 is 0% to 5.00% by mass.

20. The strengthened glass ceramic of claim 19, wherein, The composition of the strengthened glass ceramic at the center or the compressive stress layer, in terms of mass percentage of oxides, comprises: SiO2 is 35.00% to 40.00% by mass; and / or, Al2O3 is 34.00% to 42.00% by mass; and / or, ZrO2 is 5.00% to 6.00% by mass; and / or, MgO is 2.50% to 3.50% by mass; and / or, ZnO is 9.00% to 11.00% by mass; and / or, Na2O is 2.00% to 6.00% by mass; and / or, K2O is 0% to 1.00% by mass; and / or, Li2O is 2.00% to 3.00% by mass; and / or, CaO is 0% to 1.50% by mass; and / or, B2O3 is 0% to 4.00% by mass; and / or, BaO is 0.50% to 4.00% by mass; and / or, Y2O3 is 0% to 2.00% by mass; and / or, La2O3 is 0% to 3.00% by mass.

21. The strengthened glass ceramic of any one of claims 1 to 15, wherein, The average crystal size in the strengthened glass ceramic is not more than 20 nm; and / or The total content of crystalline phases in the strengthened glass ceramic is 25% to 60% by mass.

22. The strengthened glass ceramic of claim 21, wherein, The average crystal size in the strengthened glass ceramic is 1.0 nm to 10.0 nm; and / or The total content of crystalline phases in the strengthened glass ceramic is 30% to 55% by mass.

23. The strengthened glass ceramic of claim 22, wherein, The average crystal size in the strengthened glass ceramic is 4.0 nm to 9.0 nm; and / or The total content of crystalline phases in the strengthened glass ceramic is 40% to 50% by mass.

24. The strengthened glass ceramic of claim 23, wherein, The average crystal size in the strengthened glass ceramic is 4.0 nm to 8.0 nm.

25. The strengthened glass ceramic of claim 16, wherein, The average crystal size in the strengthened glass ceramic is not more than 20 nm; and / or The total content of crystalline phases in the strengthened glass ceramic is 25% to 60% by mass.

26. The strengthened glass ceramic of any one of claims 1-15, wherein, The strengthened glass ceramic is transparent in the visible light wavelength range.

27. The strengthened glass ceramic of claim 26, wherein, The transmittance of the strengthened glass ceramic is ≥ 85.00% for light of 550 nm wavelength at a thickness of 0.90 mm.

28. The strengthened glass ceramic of claim 27, wherein, The transmittance of the strengthened glass ceramic is ≥ 87.00% for light of 550 nm wavelength at a thickness of 0.90 mm.

29. The strengthened glass ceramic of claim 21, wherein, The strengthened glass ceramic is transparent in the visible light wavelength range.

30. The strengthened glass ceramic of any of Claims 1 to 15, wherein, The strengthened glass-ceramics have a Vickers hardness greater than or equal to 750 kgf / mm 2 ; and / or, The strengthened glass-ceramics have a fracture toughness value of 1.00 MPa.m or greater 0.5 ; and / or, The strengthened glass ceramic has |CT_AV| greater than 20.00 MPa, |CT_AV| being the absolute value of the average tensile stress; and / or, The strengthened glass ceramic has |CT_CV| greater than 25.00 MPa, |CT_CV| being the absolute value of the maximum tensile stress; and / or, The strengthened glass ceramic has CS_50 greater than 100 MPa, CS_50 being the compressive stress value at a depth of 50 μm from the main surface of the strengthened glass ceramic; and / or, The strengthened glass ceramic has a CS_80 greater than 50 MPa, the CS_80 being a compressive stress value at a depth of 80 μm from a main surface of the strengthened glass ceramic; and / or, The strengthened glass ceramic has a DOL_0 greater than 144 μm, the DOL_0 being a depth of a compressive stress layer; and / or, The strengthened glass ceramic satisfies: DOL_0>0.16t, wherein the DOL_0 is a depth of a compressive stress layer, and t is a thickness of the strengthened glass ceramic.

31. The strengthened glass ceramic of claim 30, wherein, The strengthened glass-ceramics have a Vickers hardness greater than or equal to 790 kgf / mm 2 ; and / or, The strengthened glass-ceramics have a fracture toughness value of 1.20 MPa.m or greater 0.5 ; and / or, The strengthened glass ceramic has a |CT_AV| greater than 20.00 MPa, the |CT_AV| being an absolute value of an average tensile stress; and / or, The strengthened glass ceramic has a |CT_CV| greater than 25.00 MPa, the |CT_CV| being an absolute value of a maximum tensile stress; and / or, The strengthened glass ceramic has a CS_50 greater than 100 MPa, the CS_50 being a compressive stress value at a depth of 50 μm from a main surface of the strengthened glass ceramic; and / or, The strengthened glass ceramic has a CS_80 greater than 50 MPa, the CS_80 being a compressive stress value at a depth of 80 μm from a main surface of the strengthened glass ceramic; and / or, The strengthened glass ceramic has a DOL_0 greater than 144 μm, the DOL_0 being a depth of a compressive stress layer; and / or, The strengthened glass ceramic satisfies: DOL_0>0.16t, wherein the DOL_0 is a depth of a compressive stress layer, and t is a thickness of the strengthened glass ceramic.

32. The strengthened glass ceramic of claim 31, wherein, The strengthened glass-ceramics have a fracture toughness value of 1.50 MPa.m or greater 0.5 ; and / or, The strengthened glass ceramic satisfies: DOL_0>0.16t, wherein the DOL_0 is a depth of a compressive stress layer, and t is a thickness of the strengthened glass ceramic.

33. The strengthened glass ceramic of claim 21, wherein The strengthened glass-ceramics have a Vickers hardness greater than or equal to 750 kgf / mm 2 ; and / or, The strengthened glass-ceramics have a fracture toughness value of 1.00 MPa.m or greater 0.5 ; and / or, The strengthened glass ceramic has a |CT_AV| greater than 20.00 MPa, the |CT_AV| being an absolute value of an average tensile stress; and / or, The strengthened glass ceramic has a |CT_CV| greater than 25.00 MPa, the |CT_CV| being an absolute value of a maximum tensile stress; and / or, The strengthened glass ceramic has a CS_50 greater than 100 MPa, the CS_50 being a compressive stress value at a depth of 50 μm from a main surface of the strengthened glass ceramic; and / or, The strengthened glass ceramic has a CS_80 greater than 50 MPa, the CS_80 being a compressive stress value at a depth of 80 μm from a main surface of the strengthened glass ceramic; and / or, The strengthened glass ceramic has a DOL_0 greater than 144 μm, the DOL_0 being a depth of a compressive stress layer; and / or, The strengthened glass ceramic satisfies: DOL_0>0.16t, wherein the DOL_0 is a depth of a compressive stress layer, and t is a thickness of the strengthened glass ceramic.

34. The strengthened glass ceramic of Claim 1, wherein The strengthened glass ceramic has a surface K2O mass percentage of 5.62%, 4.66%, 6.78%, 4.95%, 3.86%, 4.96%, 4.55%, 4.53%, 4.04%, 5.73%, 5.39%, 6.11%, or 5.89%; and / or, the surface Na2O mass percentage of the strengthened glass ceramic is 0% or 0.002%; and / or, the DOL_K of the strengthened glass ceramic is 12.10 μm, 11.00 μm, 9.40 μm, 15.10 μm, 14.10 μm, 13.00 μm, 11.10 μm, 19.10 μm, 18.00 μm, or 17.10 μm, and / or, the DOL_Na of the strengthened glass ceramic is 46.10 μm, 40.00 μm, 55.10 μm, 45.40 μm, 47.10 μm, 58.10 μm, 48.00 μm, 51.10 μm, 38.00 μm, 43.10 μm, 50.30 μm, 50.20 μm, or 56.40 μm; and / or, the value of Formula A is 1039, 1150, 1520, 910, 1542, 1469, 935, 995, 1780, 1054, 1500, 2010, or 2440.

35. The strengthened glass ceramic of claim 5, wherein the strengthened glass ceramic satisfies: in a K element concentration distribution curve in which the horizontal axis is the depth in μm from the main surface of the strengthened glass ceramic, and the vertical axis is the K element concentration in mass percentage on an element basis: the absolute value P1 of the average slope of the K element concentration distribution curve between the depth of 0 μm and the depth of DOL_K is 0.380, 0.315, 0.302, 0.530, 0.348, 0.193, 0.445, 0.452, 0.194, 0.440, 0.220, or 0.310; and / or, The absolute value P of the average slope of the K element concentration profile between the depth of 5 μm and the depth of 8 μm 5-8 0.74, 1.12, 1.22, 0.99, 1.04, 1.25, 0.76, 0.80, 0.79, 0.95, 0.66, 1.34 or 1.64; and / or, in a Na element concentration distribution curve in which the horizontal axis is the depth in μm from the main surface of the strengthened glass ceramic, and the vertical axis is the Na element concentration in mass percentage on an element basis: the absolute value P2 of the average slope of the Na element concentration distribution curve between the depth of 0 μm and the depth of DOL_Na is 0.02, 0.01, or 0.

03.

36. The strengthened glass ceramic of claim 9, wherein the strengthened glass ceramic satisfies: in a SLP stress distribution curve in which the horizontal axis is the depth in μm from the main surface of the strengthened glass ceramic, and the vertical axis is the stress in MPa: The absolute value K of the average slope of the SLP stress profile between the depth of 50 pm and the depth of 80 pm 50-80 is 1.92, 1.48, 1.52, 1.38, 1.70, 1.03, 1.59, 1.28, 2.29, 1.50, 1.56, or 1.73; and / or, The absolute value K of the average slope of the SLP stress profile between the depth of 80 pm and the depth of DOL_0 80-DOL-0 1.35, 1.06, 1.05, 1.33, 1.17, 0.98, 1.29, 1.09, 1.42, 1.18, or 1.

13.

37. The strengthened glass ceramic of Claim 1, wherein the composition at the center or the tensile stress layer of the strengthened glass ceramic, in mass percentage on an oxide basis, comprises: the mass percentage of SiO2 is 37.08%, 36.87%, 33.23%, 37.43%, 37.40%, 38.33%, 36.05%, 35.67%, or 32.39%; and / or, the mass percentage of Al2O3 is 35.83%, 36.98%, 36.27%, 37.52%, 36.60%, 37.07%, 34.84%, 34.55%, or 35.88%; and / or, the mass percent of Zr02 is 5.69%, 5.65%, 5.61%, 5.74%, 5.81%, 5.89%, 5.54%, or 5.48%; and / or, the mass percent of MgO is 3.00%, 2.98%, 3.04%, 3.03%, 3.06%, 3.10%, 2.92%, or 2.89%; and / or, the mass percent of ZnO is 10.77%, 10.71%, 10.55%, 10.87%, 11.01%, 11.15%, 10.46%, or 10.37%; and / or, the mass percent of Na20 is 2.86%, 2.85%, 2.89%, 3.00%, 1.69%, 2.79%, or 2.76%; and / or, the mass percent of K20 is 0%; and / or, the mass percent of Li20 is 2.35%, 1.55%, 1.50%, 1.77%, 1.60%, 1.62%, 2.28%, 2.27%, or 2.24%; 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%.

38. The strengthened glass ceramic of Claim 21, wherein, the average crystal size in the strengthened glass ceramic is 5.0 nm, 6.8 nm, 6.4 nm, 6.5 nm, 8.1 nm, or 7.0 nm; and / or the total content of crystalline phases in the strengthened glass ceramic is 48.69%, 45.11%, 49.52%, 47.85%, 54.07%, 51.56%, 45.49%, or 44.77% by mass percent.

39. The strengthened glass ceramic of claim 30, wherein, the strengthened glass ceramic has a Vickers hardness of 858 kgf / mm 2 875 kgf / mm 2 915 kgf / mm 2 850 kgf / mm 2 837 kgf / mm 2 900 kgf / mm 2 869 kgf / mm 2 889 kgf / mm 2 857 kgf / mm 2 865 kgf / mm 2 or 825 kgf / mm 2 ; and / or, the strengthened glass ceramic has a fracture toughness value of 1.67 MPa-m 0.5 , 1.69 MPa-m 0.5 , 1.75 MPa-m 0.5 , 1.65 MPa-m 0.5 , 1.94 MPa-m 0.5 , 1.73 MPa-m 0.5 , 1.68 MPa-m 0.5 , 1.71 MPa-m 0.5 or 1.77 MPa-m 0.5 ; and / or, the |CT_AV| of the strengthened glass ceramic is 50.96 MPa, 41.74 MPa, 36.56 MPa, 45.01 MPa, 41.49 MPa, 40.48 MPa, 50.27 MPa, 49.49 MPa, 36.05 MPa, 45.43 MPa, 53.86 MPa, 40.86 MPa, or 35.91 MPa; and / or, the |CT_CV| of the strengthened glass ceramic is 65.70 MPa, 54.30 MPa, 46.07 MPa, 68.75 MPa, 53.70 MPa, 53.07 MPa, 66.96 MPa, 71.25 MPa, 42.73 MPa, 60.57 MPa, 81.79 MPa, 52.40 MPa, or 44.78 MPa; and / or, the strengthened glass ceramic has a CS_50 of 199.69 MPa, 155.95 MPa, 146.48 MPa, 181.94 MPa, 181.35 MPa, 141.02 MPa, 188.73 MPa, 168.30 MPa, 188.13 MPa, 162.61 MPa, 177.13 MPa, 190.71 MPa, or 204.29 MPa; and / or, the strengthened glass ceramic has a CS_80 of 142.01 MPa, 111.53 MPa, 100.86 MPa, 140.44 MPa, 130.30 MPa, 110.00 MPa, 140.99 MPa, 129.89 MPa, 119.54 MPa, 117.60 MPa, 130.38 MPa, 138.72 MPa, or 152.35 MPa; and / or, the strengthened glass ceramic has a DOL_0 of 185.12 µm, 185.63 µm, 176.34 µm, 185.81 µm, 191.19 µm, 192.04 µm, 189.59 µm, 199.08 µm, 164.11 µm, 187.76 µm, 191.43 µm, 197.80 µm, or 215.20 µm.

40. The strengthened glass ceramic of any of Claims 1 to 15, wherein, the strengthened glass ceramic has a single bar static compressive strength of greater than 800 N, wherein the single bar static compressive strength is measured by applying a vertical downward load step by step at a rate of 10 mm / min to the center of the main surface of the strengthened glass ceramic having a thickness of greater than 0.7 mm using a 10 mm diameter round head metal presser bar; and / or, the strengthened glass ceramic has a pass rate of greater than or equal to 50%, wherein the pass rate is determined by performing a 2.5 m drop test at a fixed height using 80 mesh silicon carbide sandpaper on the strengthened glass ceramic having a thickness of greater than 0.7 mm, and wherein the strengthened glass ceramic is considered to pass if the glass sample does not break after the drop test; and / or, the strengthened glass ceramic has a center ball impact energy of greater than 0.7 J, wherein the center ball impact energy is measured by performing a ball drop impact test using a 130 g steel ball on the strengthened glass ceramic having a thickness of greater than 0.7 mm.

41. The strengthened glass ceramic of claim 40, wherein, the strengthened glass ceramic has a single bar static compressive strength of greater than 850 N, wherein the single bar static compressive strength is measured by applying a vertical downward load step by step at a rate of 10 mm / min to the center of the main surface of the strengthened glass ceramic having a thickness of greater than 0.7 mm using a 10 mm diameter round head metal presser bar; and / or, the strengthened glass ceramic has a pass rate of greater than or equal to 60%, wherein the pass rate is determined by performing a 2.5 m drop test at a fixed height using 80 mesh silicon carbide sandpaper on the strengthened glass ceramic having a thickness of greater than 0.7 mm, and wherein the strengthened glass ceramic is considered to pass if the glass sample does not break after the drop test; and / or, A 130 g steel ball is used to impact the strengthened glass ceramic having a thickness greater than 0.7 mm to perform a ball drop impact test, and the central ball drop impact energy that the strengthened glass ceramic can withstand is tested. The strengthened glass ceramic can withstand a central ball drop impact energy greater than 0.8 J.

42. The strengthened glass ceramic of claim 40, wherein The strengthened glass ceramic having a thickness greater than 0.7 mm is subjected to a 2.5 m fixed height drop test using 80 mesh silicon carbide sandpaper. If the glass sample does not break after dropping, it is recorded as passing. The passing rate of the strengthened glass ceramic is greater than or equal to 70%.

43. The strengthened glass ceramic of Claim 33, wherein, A 10 mm diameter round head metal pressure rod is used to vertically downwardly apply a load at a rate of 10 mm / min to the center of the main surface of the strengthened glass ceramic having a thickness greater than 0.7 mm to test the single rod static pressure strength that the strengthened glass ceramic can withstand. The strengthened glass ceramic can withstand a single rod static pressure strength greater than 800 N; and / or, The strengthened glass ceramic having a thickness greater than 0.7 mm is subjected to a 2.5 m fixed height drop test using 80 mesh silicon carbide sandpaper. If the glass sample does not break after dropping, it is recorded as passing. The passing rate of the strengthened glass ceramic is greater than or equal to 50%; and / or, A 130 g steel ball is used to impact the strengthened glass ceramic having a thickness greater than 0.7 mm to perform a ball drop impact test, and the central ball drop impact energy that the strengthened glass ceramic can withstand is tested. The strengthened glass ceramic can withstand a central ball drop impact energy greater than 0.7 J.

44. The strengthened glass ceramic of any of Claims 1 to 15, wherein, The strengthened glass-ceramics are prepared by chemical strengthening treatment of a glass-ceramic having a fracture toughness not less than 1.40 MPa.m 0.5 .

45. The strengthened glass ceramic of claim 44, wherein, The strengthened glass-ceramics are made from a glass-ceramic having a fracture toughness not less than 1.40 MPa.m 0.5 by at least two steps of chemical strengthening.

46. The strengthened glass ceramic of claim 45, wherein, a glass-ceramic having a fracture toughness not less than 1.40 MPa·m 0.5 The strengthened glass-ceramic is prepared by first placing a glass-ceramic having a fracture toughness not less than 1.40 MPa·m 0.5 in a molten salt bath comprising a sodium salt and having a mass percentage of sodium salt greater than or equal to 20%, performing a first strengthening treatment, and then placing the glass-ceramic in a molten salt bath comprising a potassium salt and having a mass percentage of potassium salt greater than or equal to 90%, performing a second strengthening treatment.

47. The strengthened glass ceramic of Claim 33, wherein The strengthened glass-ceramics are prepared by chemical strengthening treatment of a glass-ceramic having a fracture toughness not less than 1.40 MPa.m 0.5 .

48. A cover glass, characterized by The cover glass is made of the strengthened glass ceramic according to any one of claims 1-47.

49. An electronic device, comprising: The electronic device comprises the strengthened glass ceramic according to any one of claims 1-47.

50. The electronic device of claim 49, wherein, The electronic device comprises a housing comprising the strengthened glass ceramic according to any one of claims 1-47.

51. The electronic device of claim 50, wherein, The housing comprises a display screen cover plate comprising the strengthened glass ceramic according to any one of claims 1-47.

52. The electronic device of claim 50 or 51, wherein, The housing comprises a back cover comprising the strengthened glass ceramic according to any one of claims 1-47.

53. The electronic device of claim 50 or 51, wherein, The electronic device further comprises a camera assembly, and 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 1-47.

54. The electronic device of claim 49 or 50, wherein, The electronic device further comprises a middle frame comprising the strengthened glass ceramic according to any one of claims 1-47.

55. A glass article, characterized by, The glassware comprises the strengthened glass ceramic according to any one of claims 1-47.

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