Three-step ion exchange (Tiox) glass strengthening method with improved stress distribution

Abstract

Glass articles having high surface compressive stress (CS) and a high CS integrated area are provided. Methods of making such articles include a chemical ion exchange process.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to U.S. Provisional Application Serial No. 63 / 600302, filed November 17, 2023, and U.S. Provisional Application Serial No. 63 / 539900, filed September 22, 2023, pursuant to 35 USC § 119, the contents of each of which are incorporated herein by reference in their entirety. Technical Field

[0003] This disclosure relates to glass articles having high surface compressive stress (CS) and high CS integral area, and to a chemical ion exchange process for preparing such glass articles. Background Technology

[0004] Device designs in the consumer electronics market are constantly evolving. Designs incorporating 2.5D and 3D configurations are becoming increasingly common, as these features enhance the aesthetics of devices. Handheld devices (such as mobile phones and tablets) and heavy-duty consumer electronics devices (such as headsets), other applications (such as automotive interior displays), and complex devices (such as foldable phones) with 2.5D or 3D cover glass are susceptible to impact events, which can introduce defects. Impact events are a common cause of cover glass failure. To address this failure mode, compressive stress is typically added to the surface of the cover glass to help resist damage and failure. Regarding survivability in these events, the depth of damage is related to the depth of compressive stress.

[0005] Chemical strengthening is a method for imparting a desired and / or engineered stress distribution in glass articles, such as cover glass, having one or more of the following parameters: compressive stress (CS), depth of compression (DOC), and maximum center tension (CT). The compressive stress in many glass articles, including those with engineered stress distributions, is highest or peaks at the glass surface and decreases from the peak as it moves deeper into the article away from the surface. Furthermore, the stress is zero at some internal locations within the glass article before it becomes tensile stress. Chemical strengthening of alkali-containing glasses by ion exchange (IOX) is a proven method in this field.

[0006] Glass manufacturers, as well as manufacturers of handheld and consumer devices, have long strived to improve the protective capabilities of glass-containing devices, shielding them from strong impacts. Summary of the Invention

[0007] This disclosure relates to glass articles having various configurations, including conventional 2D (flat), 2.5D, and 3D, and methods of manufacturing said glass articles. A conventional 2D configuration refers to eyeglasses that are considered to have no edges or be completely flat with edges at 90 degrees. A 2.5D configuration, as mentioned herein, refers to glass that has curvature at the edges (generally considered to be slight curvature). As for 3D configurations, those eyeglasses have curvature at all locations, typically significant curvature. These glass articles can be used, for example, in consumer devices and automotive interiors.

[0008] On one hand, the glass article includes: opposite first and second surfaces defining a body of the article having a thickness (t); a stress distribution of the body including: a peak region extending from the first surface to a knee located at a layer depth (DOL); a peak compressive stress (CSmax) of the peak region greater than or equal to 1000 MPa, or 1100 MPa, or 1200 MPa, or 1300 MPa, or 1400 MPa; a tail region extending from the knee to the center of the glass article; and having a center tension (CT) and a depth of compression (DOC). The article has high compressive stress extending over a certain depth range, such that the compressive stress integral remains above a value above 5 micrometers and gradually extends to higher depths, up to 12 micrometers, 15 micrometers, 20 micrometers, 25 micrometers, and even 30 micrometers. This value corresponds to a significantly improved probability of survivability in high-stress impact events, obtained by providing significantly improved residual strength or failure stress within said depth range compared to the compressive stress distribution of the prior art. In one or more embodiments, the compressive stress integral at a depth of 5 micrometers is greater than or equal to 5.2 MPa·mm.

[0009] On one hand, the glass article comprises: opposite first and second surfaces defining a body of the article with a thickness (t) greater than or equal to 0.70 mm and less than or equal to 1.3 mm; a stress distribution of the body comprising: a peak region extending from the first surface to an inflection point located at a layer depth (DOL) greater than or equal to 20 micrometers; a peak compressive stress (CSmax) of the peak region greater than or equal to 1000 MPa, or 1100 MPa, or 1200 MPa, or 1300 MPa, or 1400 MPa; and a tail region extending from the inflection point to the center of the glass article, and having a center tension (CT) and a depth of compression (DOC) greater than or equal to 25 micrometers.

[0010] On one hand, a method of manufacturing a glass article having opposing first and second surfaces defining a body having a thickness (t), the method comprising: exposing the glass substrate to a first ion exchange (IOX-1) treatment for a first duration at a first temperature below the strain point of a glass substrate containing an alkali metal oxide in a base composition, the IOX-1 treatment comprising a first bath containing one or more molten potassium salts; after the IOX-1, exposing the glass substrate to a second ion exchange (IOX-2) treatment for a second duration at a second temperature greater than or equal to the first temperature and less than the strain point, the IOX-2 treatment comprising a second bath containing a mixture of ion-exchangeable molten salts and optional cleaning additives, the second duration being shorter than the first duration; and after the IOX-2, exposing the glass substrate to a third ion exchange (IOX-3) treatment for a third duration at a third temperature less than the first temperature, the IOX-3 treatment comprising a third bath containing one or more molten potassium salts, the third duration being shorter than the first duration.

[0011] Further features and advantages will be set forth in the detailed description below, and will be apparent in part from the description or to those skilled in the art by practice of the embodiments described herein (including the detailed description below, the claims, and the drawings).

[0012] It should be understood that both the foregoing general description and the following detailed description describe various embodiments and are intended to provide an overview or framework for understanding the nature and characteristics of the claimed subject matter. Drawings are included to provide a further understanding of the various embodiments, and these drawings are incorporated in and form a part of this specification. The drawings illustrate the various embodiments described herein and, together with the description, serve to explain the principles and operation of the claimed subject matter. Attached Figure Description

[0013] The accompanying drawings, which are incorporated in and form part of this specification, illustrate several embodiments described below.

[0014] Figure 1 A cross-section of a glass having a compressive stress layer on its surface is schematically depicted according to an embodiment disclosed and described herein;

[0015] Figure 2A It is a plan view of an exemplary electronic device that includes any of the glass articles disclosed herein;

[0016] Figure 2B yes Figure 2A A perspective view of an exemplary electronic device;

[0017] Figure 3 This is an exemplary stress distribution across the thickness of a chemically strengthened glass article;

[0018] Figure 4 This is another exemplary stress distribution across the thickness of chemically strengthened glass articles;

[0019] Figure 5 This is a graph of the concentrations (mol%) of K₂O, Na₂O, and Li₂O versus depth (micrometers) for Example 2-I;

[0020] Figure 6 It is a graph depicting the modeled stress distribution of compressive stress (MPa) versus depth (z µm) for various examples in Table 1;

[0021] Figure 7 This is a graph of compressive stress (MPa) versus thickness (micrometers) for Example 1;

[0022] Figure 8 Based on Figure 7 Example 1 shows a graph of compressive stress integral (MPa•mm) versus thickness (micrometers);

[0023] Figure 9 This is a graph of compressive stress (MPa) versus thickness (micrometers) for Example 2-II;

[0024] Figure 10 Based on Figure 9 Example 2-II shows a graph of compressive stress integral (MPa•mm) versus thickness (micrometers);

[0025] Figure 11 This is a graph of compressive stress (MPa) versus thickness (micrometers) for Example 3;

[0026] Figure 12 Based on Figure 11 Example 3 shows a graph of compressive stress integral (MPa•mm) versus thickness (micrometers);

[0027] Figure 13 This is a graph showing the failure stress (MPa) versus defect depth (micrometers) for Example 1 and Comparative Example B;

[0028] Figure 14 This is a graph of the failure probability (%) versus failure stress (MPa) for Example 1;

[0029] Figure 15 This is a graph of the failure probability (%) versus failure stress (MPa) for Example 7;

[0030] Figure 16 This is the load-deflection plot for Example 7;

[0031] Figure 17 This is a normalized load-deflection plot of Example 7 relative to deflection × thickness × modulus of elasticity; and

[0032] Figure 18 The following is an example micrograph of an article based on the DIOX-B comparative example in this article, showing the defects and their depths introduced by aerodynamic wear, which are revealed later after ring-on-ring (ROR) testing. Detailed Implementation

[0033] Before describing several exemplary embodiments, it should be understood that this disclosure is not limited to the details of the construction or method steps set forth in the following disclosure. The disclosure provided herein can have other embodiments and can be practiced or carried out in various ways.

[0034] Throughout this specification, references to "one embodiment," "some embodiments," "various embodiments," "one or more embodiments," or "an embodiment" mean that a particular feature, structure, material, or characteristic described in connection with the embodiment is included in at least one embodiment of this disclosure. Therefore, phrases such as "in one or more embodiments," "in some embodiments," "in various embodiments," "in one embodiment," or "in an embodiment" appearing throughout this specification do not necessarily refer to the same embodiment or only one embodiment. Furthermore, in one or more embodiments, a particular feature, structure, material, or characteristic may be combined in any suitable manner.

[0035] Definition and measurement techniques

[0036] The terms "glass article" and "glass substrate" are used to include any object made of glass. The glass substrate according to one or more embodiments may be selected from soda-lime silicate glass, alkali aluminosilicate glass, alkali borosilicate glass, alkali aluminosilicate glass, and alkali phosphate glass.

[0037] The “base composition” is the chemical composition of the substrate prior to any ion exchange (IOX) treatment. That is, the base composition is undoped with any ions from the IOX. The composition at the center of an IOX-treated glass article is typically the same as the base composition, provided that the ions supplied to the IOX do not diffuse to the center of the substrate. In one or more embodiments, the center composition at the center of the glass article comprises the base composition.

[0038] It should be noted that the terms “substantially” and “about” can be used herein to indicate the degree of uncertainty inherent in any quantitative comparison, value, measurement, or other representation. These terms are also used herein to indicate the extent to which a quantitative representation may differ from the stated reference without altering the essential function of the subject matter. Thus, for example, a glass article “substantially free of MgO” is a glass article in which MgO is not actively added to or incorporated into the glass article but may be present in very small amounts as a contaminant. As used herein, the term “about” means that a quantity, size, formulation, parameter, and other quantity and characteristic is not exact and need not be exact, but may be approximate and / or larger or smaller as required, reflecting tolerances, conversion factors, rounding, measurement errors, and other factors known to those skilled in the art. When the term “about” is used to describe a value or range endpoint, this disclosure should be understood to include the specific value or endpoint mentioned. Regardless of whether a numerical or range endpoint in the specification is described with “about,” the numerical or range endpoint is intended to include two embodiments: one modified by “about” and one not modified by “about.” It should be further understood that each endpoint of the range is valid both in relation to and independent of the other endpoint.

[0039] Unless otherwise stated, all compositions described herein are expressed as mole percent (mol%) based on oxides.

[0040] "Stress distribution" refers to the functional relationship between stress and thickness across a glass article. The compressive stress region extends from the first surface of the article to the depth of compression (DOC) and is the area where the article is under compressive stress. The central tension region extends from the DOC to include the area where the article is under tensile stress.

[0041] As used herein, the depth of compression (DOC) refers to the depth within a glass article where the stress changes from compressive stress to tensile stress. At the DOC, the stress changes from positive (compressive) stress to negative (tensile) stress, and therefore exhibits a stress value of zero. According to convention commonly used in the mechanical field, compression is represented as negative (< 0) stress, and tension as positive (> 0) stress. However, throughout this specification, the positive value of stress is compressive stress (CS), which is expressed as a positive or absolute value, i.e., CS = |CS|, as described herein. Conversely, negative values ​​of stress are tensile stresses. However, when used with the term "tension," stress or center tension (CT) can be expressed as a positive value, i.e., CT = |CT|. Center tension (CT) refers to the tensile stress in the central region or center tension region of a glass article. Maximum center tension (maximum CT or CT) maxThe center tension (PT) may occur in the nominally 0.5•t region, where t is the article thickness, allowing for precise center variation from the location of maximum tensile stress. The peak tension (PT) refers to the maximum tension measured, which may or may not be located at the center of the article.

[0042] refer to Figure 1 Glass articles include glass with a thickness t and a first region under compressive stress extending from the glass surface to a certain depth of compression (DOC) (e.g., Figure 1 The first compressive stress layer 120 and the second compressive stress layer 122 in the glass) and the second region extending from the DOC to the center or interior region of the glass under tensile stress or central tension (CT) (e.g., Figure 1 (Central area 130).

[0043] Compressive stress (CS) has a maximum or peak value, which typically occurs at the glass surface (though this is not always the case, as the peak may occur at a certain depth from the glass surface), and CS varies with the distance d from the surface according to a function. See again. Figure 1 The first compressive stress layer 120 extends from the first surface 110 to a depth d1, and the second compressive stress layer 122 extends from the second surface 112 to a depth d2. These sections together define the compression region or CS of the glass 100.

[0044] Two compressive stress layers ( Figure 1 The compressive stresses in 120 and 122 are balanced by the tension stored in the central region (130) of the glass.

[0045] Figure 3 The diagram graphically illustrates an exemplary stress distribution in a chemically strengthened glass article, the stress distribution spanning a thickness t defined by a first surface 302 and a second surface 304 opposite to the first surface of a glass article 300 according to one or more embodiments. In one or more embodiments, the thickness t may be about 3 millimeters or less, including all values ​​and subranges therein.

[0046] The stress distribution extends from the first surface 302 to the second surface 304 (or along the entire length of thickness t). Figure 3The embodiment shown illustrates a stress distribution 312 measured by SCALP as described herein. The y-axis represents the stress value, and the x-axis represents the thickness or depth within the glass article. An exemplary stress distribution 312 includes a surface CS 310, a maximum CT 320, and a first DOC 330. The stress distribution 312 has a CS layer 317 extending from the surface 302 to the first DOC 330. A second CS layer 317 extends from the surface 304 to the second DOC 332. The stress distribution 312 also has a CT layer 327 extending between the first DOC 330 and the second DOC 332.

[0047] The "knee" of stress distribution refers to the depth of the workpiece where the slope of the stress distribution transitions from steep to gentle. See, for example... Figure 4 An inflection point can refer to the transition region across a depth span where the slope changes. The stress at the inflection point is CS. k Defined as the deeper portion of the CS distribution extrapolated to the peak depth (DOL) sp The compressive stress value at (). DOL sp The report is based on measurements taken using a surface stress gauge using known methods. Figure 4 Overall, the stress distribution of compressive stress with respect to the normalized position is shown, including the peak region, inflection point, and tail region; CSmax, CS k DOL sp and DOC.

[0048] A non-zero concentration of metal oxides relative to the variation of the metal oxide concentration from the first surface to the layer depth (DOL) or along at least a majority of the article thickness (t) indicates that stress has been generated in the article due to ion exchange. This variation in metal oxide concentration may be referred to herein as a metal oxide concentration gradient. A metal oxide concentration that is non-zero and varies from the first surface to the DOL or along a portion of the thickness can be described as generating stress in the glass article. The metal oxide concentration gradient or variation is generated by chemically strengthening the glass substrate, wherein multiple first metal ions in the glass substrate exchange with multiple second metal ions.

[0049] As used herein, the terms “depth of exchange,” “depth of layer” (DOL), “chemical depth of layer,” and “depth of chemical layer” are used interchangeably and generally describe the depth at which ion exchange occurs for a particular ion facilitated by an ion exchange process (IOX). DOL refers to the depth within a glass article (i.e., the distance from the surface of the glass article to its interior region) at which ions of metal oxides or alkali metal oxides (e.g., metal ions or alkali metal ions) diffuse into the glass substrate, where the ion concentration reaches a minimum, determined by glow discharge-optical emission spectroscopy (GD-OES). In some embodiments, DOL is given as the exchange depth of the slowest or largest ion introduced by the ion exchange (IOX) process. The DOL relative to potassium (DOL) K (DOL) refers to the depth to which the potassium content of the glass reaches the potassium content of the substrate below. This is relative to the sodium content of DOL (DOL). Na ( ) is the depth to which the sodium content of the glass product reaches the sodium content of the substrate below.

[0050] Unless otherwise stated, CT and CS are expressed in megapascals (MPa) in this document, thickness in millimeters, and DOC and DOL in micrometers (micrometers).

[0051] Compressive stress (including surface / peak CS, CS) max The surface stress can be measured using a commercially available instrument (such as the FSM-6000 manufactured by Orihara Industrial Co., Ltd. (Japan)) using a surface stress meter (FSM). Surface stress measurement relies on the accurate measurement of the stress optical coefficient (SOC) associated with the birefringence of the glass. The SOC is measured according to Procedure C (Glass Disc Method) as described in ASTM Standard C770-16 entitled "Standard Test Method for Measurement of Glass Stress-Optical Coefficient," the contents of which are incorporated herein by reference in their entirety.

[0052] Maximum center tension (CT) or peak tension (PT) and stress retention value are measured using Scattered Light Polarimeter (SCALP) techniques known in the art. Stress distribution and depth of compression (DOC) can be measured using the Refractive Near-Field (RNF) method or SCALP. When measuring stress distribution using the RNF method, the maximum CT value provided by SCALP is utilized in the RNF method. Specifically, the stress distribution measured by RNF is force-balanced and calibrated to the maximum CT value provided by SCALP measurement. The RNF method is described in U.S. Patent No. 8,854,623, entitled "Systems and methods for forming a profile characteristic of a glass sample," which is incorporated herein by reference in its entirety. Specifically, the RNF method includes: placing a glass article in proximity to a reference block; generating a polarization-switched beam that switches between orthogonal polarizations at a rate of 1 Hz to 50 Hz; measuring the power quantity in the polarization-switched beam; and generating a polarization-switched reference signal, wherein the measured power quantity in each of the orthogonal polarizations is within 50% of each other. The method further includes: transmitting a polarization-switched beam through the glass sample and a reference block to different depths within the glass sample, and then using a relay optics system to relay the transmitted polarization-switched beam to a signal photodetector, wherein the signal photodetector generates a polarization-switched detector signal. The method also includes: dividing the detector signal by a reference signal to form a normalized detector signal, and determining the distribution characteristics of the glass sample based on the normalized detector signal.

[0053] Ion exchange (IOX) treatment

[0054] Chemical strengthening of a glass substrate with a base composition is accomplished by placing an ion-exchangeable glass substrate in a molten bath containing cations (e.g., K+, Na+, Ag+, etc.), which diffuse into the glass, while smaller alkali ions (e.g., Na+, Li+) in the glass diffuse into the molten bath. The smaller cations are replaced by larger cations, thereby generating compressive stress near the top surface of the glass. Tensile stress is generated inside the glass to balance the near-surface compressive stress.

[0055] Manufacturing strengthened glass with high CS and deep DOL or DOC presents processing challenges. Typically, there are two types of strengthening processes in ion-exchange manufacturing: single ion exchange (SIOX) and double ion exchange (DIOX).

[0056] SIOX is a simple one-step process and is generally a cost-effective way to perform ion exchange. The CS and DOL of SIOX are mainly determined by the bath composition, IOX temperature, and time, and they are inversely correlated with each other. This means that in order to obtain a higher CS value, the IOX time cannot be too long, and therefore the DOL cannot be increased too deeply.

[0057] DIOX is a two-step process where the first step (Step 1 or IOX-1) is designed to build a deep stress distribution (DOC), and the second step (Step 2 or IOX-2) is designed to achieve high stress distribution (CS) with a shorter DOL. DIOX is an advantageous process for building stress distributions with both high CS and deep DOC to resist damage-induced failure. However, DIOX may still lack the ability to build stress distributions with both high CS and DOL.

[0058] This paper introduces a three-step ion exchange process (TIOX). To generate a stress distribution with high CS and deep DOL and / or DOC and / or compressive stress integrals increasing with depth, the IOX process described herein comprises three ion exchange steps. The third step (Step 3 or IOX-3) combines with the conventional Step 2 (IOX-2) and Step 1 (IOX-1), offering advantages in achieving higher CS and deeper DOL than SIOX or DIOX using industry-standard ion exchange conditions.

[0059] The three steps of TIOX are referred to as Step 1, Step 2, and Step 3.

[0060] Step 1 comprises exposing the glass substrate to a first ion exchange (IOX-1) treatment for a first duration at a first temperature below the strain point of the glass substrate containing alkali metal oxides in the base composition, the IOX-1 treatment comprising a first bath containing large cations (e.g., from one or more molten potassium salts). Optional scavenging additives may be added to the bath, typically in an amount of 0.5% by weight. In one or more embodiments, the total amount of potassium salt and optional scavenging additives in the first bath is 100% by weight. In one or more embodiments, Step 1 is carried out in a 100% by weight KNO3 bath or a combination of KNO3 and K2CO3 at a relatively high temperature and a long IOX time to build a deep DOL, but still with a relatively high CS, for example, as high as that achievable with a SIOX process. In one or more embodiments, the temperature and time of IOX-1 are designed to build a deep DOL greater than 20 micrometers.

[0061] Step 2 comprises: after IOX-1, exposing the glass substrate to a second ion exchange (IOX-2) treatment for a second duration at a second temperature greater than or equal to the first temperature and less than the strain point, the IOX-2 treatment comprising a second bath containing a mixture of ion-exchangeable molten salts and optional scavenging additives, the second duration being shorter than the first duration. In one or more embodiments, Step 2 is performed in a KNO3-NaNO3 mixed bath (preferably a high NaNO3 bath) at a temperature equal to or higher than that of Step 1. In one or more embodiments, the second bath contains a molten salt mixture of Na and K cations, preferably with a Na / K weight ratio greater than 1. Optional scavenging additives may be added to the bath, typically in an amount of 0.5% by weight. In one or more embodiments, the total amount of the mixture of Na and K cation molten salts and optional scavenging additives in the second bath is 100% by weight. The aim is to exchange K ions near the surface with Na ions to reset the high Na concentration at the glass surface depleted in Step 1. Step 2 should be performed at a temperature equal to or higher than that of Step 1, for a short duration of IOX, to ensure that the depth of Na↔K ion exchange is less than that of Step 1, preferably less than half of that of Step 1. After Step 2, the surface CS decreases significantly, while the peak CS is embedded into the bulk glass. Although Step 2 may seem to contradict the goal of CS enhancement, it is precisely this step that provides some fresh Na ions near the surface for further enhancement in Step 3. The IOX-2 process parameters (bath composition, IOX temperature, and time) are designed to ensure that the CS at the surface does not drop to a negative value (from compressive stress to tensile stress).

[0062] Step 3 includes: after IOX-2, exposing the glass substrate to a third ion exchange (IOX-3) treatment for a third duration at a third temperature lower than the first temperature, the IOX-3 treatment comprising a third bath containing one or more molten potassium salts, the third duration being shorter than the first duration. Optional scavenging additives may be added to the bath, typically in an amount of 0.5% by weight. In one or more embodiments, the total amount of potassium salts and optional scavenging additives in the third bath is 100% by weight. In one or more embodiments, Step 3 is performed at a lower temperature (below Step 1) in a 100% KNO3 bath, or preferably in a KNO3-K2CO3 mixed bath for IOX enhancement. The purpose of Step 3 is to reintroduce potassium ions into the glass via K↔Na ion exchange to restore the K concentration at the surface to its maximum value. Because step 3 is performed at a lower temperature and for a shorter duration, the amount of K exchanged into the glass in this step will provide a greater boost to CS than the decrease in CS caused by K depletion near the surface through Na↔K ion exchange in step 2, which is performed at a much higher temperature (meaning a smaller decrease in CS). Therefore, higher CS and deeper DOL, DOC, and / or compressive stress integrals can be obtained than in step 1.

[0063] The TIOX method is unique and differs from existing SIOX and DIOX methods in that it provides a process that can achieve higher CS and deeper DOL than conventional SIOX and DIOX, while allowing stress to be placed at the desired depth to improve damage resistance. TIOX offers a wide processing window for strengthening glass with improved stress distribution.

[0064] In some embodiments, the methods described herein involve ion exchange, which can be achieved through thermal diffusion or electrodiffusion processes involving molten salt mixtures of Li+, Na+, K+, Rb+, Cs+, Ag+, and Tl+.

[0065] A general overview of the properties of glass products

[0066] Consumer electronics devices / displays (e.g., headsets) require chemically strengthened glass with high CS and deep DOL or DOC, which are typically subjected to high-speed impacts, such as stresses significantly exceeding 1 GPa. To withstand high-speed impacts, strengthened glass ideally has very high CS to overcome over-stress failure and deep DOL or DOC to overcome damage-induced failure.

[0067] The glass articles described herein have a stress distribution designed to provide improved protection for the glass device against strong impacts. Such devices include 3D devices with a preferred thickness of 0.70 mm to 1.3 mm. The combination of high compressive stress (Csmax) at the surface and the compressive stress integral at the desired depth improves survivability in high-stress impact events.

[0068] Alkali aluminosilicate glasses possess excellent ion exchange properties, and chemical strengthening processes have been used to achieve their high strength and toughness. Sodium aluminosilicate glasses are highly ion-exchangeable glasses with high formability and quality. Lithium aluminosilicate glasses are highly ion-exchangeable glasses with high glass quality. Substituting Al₂O₃ into the silicate glass network improves the interdiffusion of monovalent cations during ion exchange. Glasses with high strength, high toughness, and high resistance to dent cracking can be obtained through chemical strengthening in a molten salt bath (e.g., KNO₃ or NaNO₃). The stress distribution obtained through chemical strengthening can be shaped to enhance drop performance.

[0069] Therefore, lithium aluminum silicate glass, with its excellent physical properties, chemical durability, and ion exchange capacity, has attracted much attention as a cover glass. Through different ion exchange processes, greater center tension (CT), depth of compression (DOC), and high compressive stress (CS) can be achieved.

[0070] In embodiments of the glass compositions described herein, unless otherwise stated, the concentrations of the constituent components (e.g., SiO2, Al2O3, Li2O, etc.) are given as a mole percentage (mol%) based on the oxide. It should be understood that any of the various ranges of description of a component can be combined alone with any of the various ranges of description of any other component.

[0071] In glass articles, there is an alkali metal oxide with a non-zero concentration, which varies from one or both of a first surface and a second surface to the depth of layer (DOL) relative to the metal oxide. Due to the non-zero concentration of the metal oxide varying from the first surface, a stress distribution is generated. The non-zero concentration can vary along a portion of the article thickness. This variation can be measured using methods known in the art, including microprobes.

[0072] In some embodiments, the concentration variation may be continuous along a thickness range of about 10 micrometers to about 30 micrometers. In some embodiments, the concentration of the alkali metal oxide decreases from the first surface to a value between the first surface and the second surface, and increases from said value to the second surface.

[0073] The concentration of alkali metal oxides may include more than one metal oxide (e.g., a combination of Na₂O and K₂O). In some embodiments, when using two metal oxides and when the ionic radii are different from each other, at shallow depths, the concentration of ions with larger radii is greater than the concentration of ions with smaller radii, while at deeper depths, the concentration of ions with smaller radii is greater than the concentration of ions with larger radii.

[0074] The concentration of alkali metal oxides can be determined by the baseline amount of metal oxides in the glass substrate that is ion-exchanged to form the glass article; for example, the concentration can be determined relative to the base composition.

[0075] In one or more embodiments, the thickness t of the glass article is in the range of 0.3 mm to 1.5 mm, and all values ​​and sub-ranges therebetween; and / or t may be less than or equal to 1.2 mm, less than or equal to 1.1 mm, less than or equal to 1.0 mm, less than or equal to 0.9 mm, less than or equal to 0.80 mm, less than or equal to 0.70 mm, less than or equal to 0.65 mm, less than or equal to 0.50 mm and / or greater than or equal to 0.5 mm, greater than or equal to 0.6 mm, greater than or equal to 0.7 mm, greater than or equal to 0.8 mm, including all values ​​and sub-ranges therebetween. In one or more embodiments, the thickness t is in the range of 0.70 mm to 1.3 mm.

[0076] In one or more embodiments, the maximum compressive stress (CS) of the glass article max ) Greater than or equal to 950 MPa, greater than or equal to 1000 MPa, greater than or equal to 1050 MPa, greater than or equal to 1100 MPa, greater than or equal to 1150 MPa, greater than or equal to 1200 MPa, greater than or equal to 1250 MPa, greater than or equal to 1300 MPa, greater than or equal to 1350 MPa, greater than or equal to 1400 MPa, including all values ​​and subranges in between.

[0077] In one or more embodiments, the glass article comprises: a compressive stress integral at a depth of 5 micrometers, said compressive stress integral being greater than or equal to 5.2 MPa·mm, and optionally including one or more of the following: a compressive stress integral at a depth of 8 micrometers being greater than or equal to 8.5 MPa·mm; a compressive stress integral at a depth of 12 micrometers being greater than or equal to 11.7 MPa·mm; a compressive stress integral at a depth of 16 micrometers being greater than or equal to 14.1 MPa·mm; a compressive stress integral at a depth of 20 micrometers being greater than or equal to 15.7 MPa·mm; and a compressive stress integral at a depth of 25 micrometers being greater than or equal to 16.7 MPa·mm.

[0078] In one or more embodiments, the glass article comprises: a tensile stress factor K t It is the fragility limit in units of stress intensity factor, for example, MPa√m. As used in this paper, the quantity K... t The tensile stress factor is given by equation (I):

[0079] ,

[0080] Where σ is represented by one of the in-plane components (since it is assumed that the in-plane components are equal), and z is the position in the thickness direction. To obtain the Kt value in MPa√m, the stress value under integration should be in MPa, while the thickness position scale z should be in meters.

[0081] In some embodiments, the glass articles contain ion-exchanged sodium and potassium. In some embodiments, the glass articles contain ion-exchanged lithium, sodium, and potassium.

[0082] In some implementations, the glass products contain ion-exchange lithium, sodium, potassium and metal ion dopants, such as silver, copper, zinc, titanium dioxide, etc., to introduce additional functions, such as antimicrobial and self-cleaning properties.

[0083] In some implementations, when tested according to ASTM C1499-19 using a 0.5-inch diameter loading ring and a 1-inch diameter support ring, the glass article contains one or more of the following: at a defect depth of 5 micrometers, the failure stress is greater than or equal to 1500 MPa, 1600 MPa, 1700 MPa, 1800 MPa, or 1900 MPa; at a defect depth of 9 micrometers, the failure stress is greater than or equal to 1200 MPa, 1300 MPa, 1400 MPa, 1500 MPa, or 1600 MPa; at a defect depth of 13 micrometers, the failure stress is greater than or equal to 600 MPa, 700 MPa, 800 MPa, or 900 MPa; and at a defect depth of 25 micrometers, the failure stress is greater than or equal to 400 MPa or 500 MPa. The “defect depth” (inspection depth or crack tip depth) mentioned refers to the location or depth at which a crack tip is formed in a defect (or the defect itself, in the absence of a crack) before strength testing. Figure 18 This is an example micrograph of the DIOX-B comparative example in this article, showing the defect introduced by aerodynamic wear and its depth, which will be revealed later after ring-to-ring (ROR) testing. The defect depth is shown as 37.79 micrometers.

[0084] In some implementations, in the absence of surface etching, using a 0.5-inch diameter loading ring and a 1-inch diameter support ring according to ASTM C1499-19 63.2, under quasi-static and / or dynamic conditions, in a 2-parameter Weibull distribution, at a failure probability of 63.2%, the property strength of the glass article is greater than or equal to 1.5 GPa and less than or equal to 4 GPa, including greater than or equal to 2 GPa and less than or equal to 3 GPa.

[0085] In some embodiments, the article comprising a pre-loaded stress distribution is combined with surface etching, which involves removing a certain amount of material, including, for example, 0.2 micrometers to 20 micrometers per side, preferably 0.3 micrometers to 8 micrometers per side, more preferably 0.5 micrometers to 3 micrometers per side, and even more preferably 1 micrometer to 2.5 micrometers per side, to reduce the depth or sharpness of pre-existing defects, thereby increasing the strength of the remaining defects to a level capable of withstanding high-stress contact events. In some desired distributions, the surface CS is designed to be less than 1100 MPa because the distribution described herein can exhibit sufficient performance when combined with some surface etching, in which material is etched from the glass surface to improve its strength by eliminating pre-existing defects, reducing their depth, and / or changing their shape through the etching process. In this case, the combination of higher stress regions having at least one of depths of 5 micrometers, 8 micrometers, 12 micrometers, 16 micrometers, 20 micrometers, or 25 micrometers provides excellent resistance to fracture for certain defects compared to prior art distributions. These defects include edge-finishing flaws, which can be very costly to reduce to less than 10 micrometers in size when the cover glass has a complex 3D shape. Other defects that may require this deeper protection include some 3D forming defects. Furthermore, defects that develop on the glass surface during use are common, including scratches that can produce median cracks deeper than 10 micrometers, sometimes reaching 15, 20, or even 25 micrometers. Increasing the compressive stress zone to these depths can help increase the residual strength or failure stress of such defects to a significantly greater extent than what can be provided by existing distributions.

[0086] In some implementations, such as glass articles further combined with surface etching, the characteristic strength according to ASTM C1499-19 using a 0.5-inch loading ring and a 1-inch support ring, under quasi-static conditions, in a two-parameter Weibull distribution, at a failure probability of 63.2%, is greater than or equal to 2 GPa to less than or equal to 8 GPa, including greater than or equal to 6.5 GPa; and / or according to ASTM C1499-19 using a 0.5-inch diameter loading ring and a 1-inch diameter support ring, under dynamic conditions, in a two-parameter Weibull distribution, at a failure probability of 63.2%, is greater than or equal to 5 GPa to less than or equal to 10 GPa, including greater than or equal to 8.7 GPa.

[0087] In some embodiments, with or without surface etching, the normalized deflection of the glass article, calculated as deflection (in mm) × thickness (in mm) × modulus of elasticity (in Pa), is greater than or equal to 80 (10^9 N or GN), including greater than or equal to 100 (10^9 N or GN), greater than or equal to 120 (10^9 N or GN), greater than or equal to 140 (10^9 N or GN), or greater than or equal to 150 (10^9 N or GN).

[0088] Aspect (a) is a glass article comprising: opposing first and second surfaces defining a body of the article having a thickness (t); a stress distribution of the body comprising: a peak region extending from the first surface to an inflection point located at a layer depth (DOL); and a peak compressive stress (CS) of the peak region. max The peak compressive stress is greater than or equal to 1000 MPa; the tail region extends from the inflection point to the center of the glass article, the tail region has central tension (CT) and includes a depth of compression (DOC); and the compressive stress integral at a depth of 5 micrometers, the compressive stress integral being greater than or equal to 5.2 MPa·mm.

[0089] Aspect (b) is the glass article according to aspect (a), wherein t is in the range of 0.30 mm to 1.5 mm.

[0090] Aspect (c) is a glass article according to aspect (a) or (b), wherein the DOC is greater than or equal to 0.035•t.

[0091] Aspect (d) is a glass article according to any one of aspects (a) to (c), comprising one or more of the following: the integral of the compressive stress at a depth of 8 micrometers is greater than or equal to 8.5 MPa·mm; the integral of the compressive stress at a depth of 12 micrometers is greater than or equal to 11.7 MPa·mm; the integral of the compressive stress at a depth of 16 micrometers is greater than or equal to 14.1 MPa·mm; the integral of the compressive stress at a depth of 20 micrometers is greater than or equal to 15.7 MPa·mm; and the integral of the compressive stress at a depth of 25 micrometers is greater than or equal to 16.7 MPa·mm.

[0092] Aspect (e) is a glass article comprising: opposing first and second surfaces defining a body of the article having a thickness (t) greater than or equal to 0.70 mm and less than or equal to 1.3 mm; a stress distribution of the body comprising: a peak region extending from the first surface to an inflection point located at a layer depth (DOL) greater than or equal to 20 micrometers; and a peak compressive stress (CS) of the peak region. max The peak compressive stress is greater than or equal to 1000 MPa; and the tail region extends from the inflection point to the center of the glass article, the tail region having central tension (CT) and including a depth of compression (DOC) greater than or equal to 25 micrometers.

[0093] Aspect (f) is a glass article according to aspect (e) comprising a compressive stress integral at a depth of 5 micrometers, said compressive stress integral being greater than or equal to 5.2 MPa·mm, and optionally including one or more of the following: the compressive stress integral at a depth of 8 micrometers being greater than or equal to 8.5 MPa·mm; the compressive stress integral at a depth of 12 micrometers being greater than or equal to 11.7 MPa·mm; the compressive stress integral at a depth of 16 micrometers being greater than or equal to 14.1 MPa·mm; the compressive stress integral at a depth of 20 micrometers being greater than or equal to 15.7 MPa·mm; and the compressive stress integral at a depth of 25 micrometers being greater than or equal to 16.7 MPa·mm.

[0094] Aspect (g) is a glass article according to any one of aspects (a) to (f) which includes a 3D configuration.

[0095] Aspect (h) is a glass article according to any one of aspects (a) to (g), wherein the peak compressive stress (CS) in the peak region is... max ) Greater than or equal to 1100 MPa, 1200 MPa, 1300 MPa, 1400 MPa or 1500 MPa.

[0096] Aspect (i) is a glass article according to any one of aspects (a) to (h) comprising a lithium aluminum silicate core composition.

[0097] Aspect (j) is the glass article according to aspect (i), wherein the Na2O / Li2O molar ratio of the lithium aluminum silicate central composition is in the range of greater than or equal to 1.5 to less than or equal to 2.1.

[0098] Aspect (k) is a glass article according to aspect (i) or (j), wherein the lithium aluminum silicate core composition comprises: about 50 mol% to about 69 mol% SiO2; about 12.5 mol% to about 25 mol% Al2O3; about 0 mol% to about 8 mol% B2O3; about 0.01 mol% to about 2 mol% K2O; about 11.0 mol% to about 15.0 mol% Na2O; and about 0.5 mol% to about 10 mol% Li2O.

[0099] Aspect (l) is a consumer electronic product comprising: a housing having a front surface, a rear surface and a side surface; electrical components at least partially disposed within the housing, the electrical components including at least a controller, a memory and a display disposed at or adjacent to the front surface of the housing; and a glass article according to any one of aspects (a) to (k), the glass article being disposed above the display.

[0100] Aspect (m) is a method of manufacturing a glass article having opposing first and second surfaces defining a body having a thickness (t), the method comprising: exposing the glass substrate to a first ion exchange (IOX-1) treatment for a first duration at a first temperature below the strain point of a glass substrate containing an alkali metal oxide in a base composition, the IOX-1 treatment comprising a first bath containing one or more molten potassium salts; after the IOX-1, exposing the glass substrate to a second ion exchange (IOX-2) treatment for a second duration at a second temperature greater than or equal to the first temperature and less than the strain point, the IOX-2 treatment comprising a second bath containing a mixture of ion-exchangeable molten salts and optional cleaning additives, the second duration being shorter than the first duration; and after the IOX-2, exposing the glass substrate to a third ion exchange (IOX-3) treatment for a third duration at a third temperature less than the first temperature, the IOX-3 treatment comprising a third bath containing one or more molten potassium salts, the third duration being shorter than the first duration.

[0101] Aspect (n) is the method according to aspect (m), wherein: the first bath contains greater than or equal to 90% by weight of potassium nitrate (KNO3) and less than or equal to 10% by weight of sodium nitrate (NaNO3); the mixture of the ion-exchangeable molten salt in the second bath contains potassium nitrate (KNO3) and sodium nitrate (NaNO3), and the sodium to potassium (Na:K) ratio is greater than 1; and the third bath contains: 0 to less than or equal to 15% by weight of potassium carbonate (K2CO3) and potassium nitrate (KNO3), reaching a total of 100 wt.%.

[0102] Aspect (o) is the method according to aspect (m) or (n), wherein: the first duration is greater than or equal to 5 hours and less than or equal to 50 hours; the second duration is greater than or equal to 0.5 hours and less than or equal to 2 hours; and the third duration is greater than or equal to 1 hour and less than 15 hours.

[0103] Aspect (p) is the method according to any one of aspects (m) to (o), wherein: the first temperature is greater than or equal to 400°C and less than or equal to 500°C; the second temperature is greater than or equal to 400°C and less than or equal to 550°C; and the third temperature is greater than or equal to 350°C and less than 450°C.

[0104] Aspect (q) is the method according to any one of aspects (m) to (p), wherein the second bath comprises: greater than or equal to 5% by weight to less than or equal to 45% by weight of potassium nitrate (KNO3) and greater than or equal to 55% by weight to less than or equal to 95% by weight of sodium nitrate (NaNO3), reaching a total of 100 wt.%.

[0105] Aspect (r) is the method according to any one of aspects (m) to (q), which does not include any thermal relaxation step performed in the absence of a molten salt bath between said IOX-1 and said IOX-3.

[0106] Aspect (s) is the method according to any one of aspects (m) to (r), wherein the glass substrate comprises: a sodium calcium silicate composition; an alkali aluminosilicate composition; an alkali borosilicate composition; an alkali aluminosilicate composition or an alkali phosphate composition.

[0107] Aspect (t) is the method according to any one of aspects (m) to (s), wherein the glass substrate comprises a central composition comprising: a Na2O / Li2O molar ratio in the range of greater than or equal to 1.5 to less than or equal to 2.1, and / or about 50 mol% to about 69 mol% SiO2; about 12.5 mol% to about 25 mol% Al2O3; about 0 mol% to about 8 mol% B2O3; about 0.01 mol% to about 2 mol% K2O; about 11.0 mol% to about 15.0 mol% Na2O; and about 0.5 mol% to about 10 mol% Li2O.

[0108] Aspect (u) is any one of aspects (a) to (t), wherein the glass article comprises, according to ASTM C1499-19, a loading ring of 0.5 inches in diameter and a support ring of 1 inch in diameter, under quasi-static conditions, in a two-parameter Weibull distribution, at a failure probability of 63.2%, a characteristic strength greater than or equal to 1.5 GPa to less than or equal to 8 GPa, including 1.5 GPa to 4 GPa and 4 GPa to 8 GPa; and / or, according to ASTM C1499-19, a loading ring of 0.5 inches in diameter and a support ring of 1 inch in diameter, under dynamic conditions, in a two-parameter Weibull distribution, at a failure probability of 63.2%, a characteristic strength greater than or equal to 1.5 GPa to less than or equal to 10 GPa, including 1.5 GPa to 4 GPa and 5 GPa to 10 GPa.

[0109] Aspect (v) is any one of aspects (a) to (u), in the absence of surface etching, wherein the glass article comprises, according to ASTM C1499-19, a loading ring of 0.5 inches in diameter and a support ring of 1 inch in diameter, under quasi-static and / or dynamic conditions, in a 2-parameter Weibull distribution, with a failure probability of 63.2%, a characteristic strength greater than or equal to 1.5 GPa to less than or equal to 4 GPa.

[0110] Aspect (w) is any one of aspects (a) to (u), wherein the glass article further includes surface etching after ion exchange.

[0111] Aspect (x) is aspect (w), wherein the glass article comprises, according to ASTM C1499-19, under quasi-static conditions, in a 2-parameter Weibull distribution, at a failure probability of 63.2%, a characteristic strength greater than or equal to 4 GPa to less than or equal to 8 GPa, including greater than or equal to 6.5 GPa; and / or, according to ASTM C1499-19, using a loading ring of 0.5 inches in diameter and a support ring of 1 inch in diameter, under dynamic conditions, in a 2-parameter Weibull distribution, at a failure probability of 63.2%, a characteristic strength greater than or equal to 5 GPa to less than or equal to 10 GPa, including greater than or equal to 8.7 GPa, using a loading ring of 0.5 inches in diameter and a support ring of 1 inch in diameter, in a failure probability of 63.2%;

[0112] Aspect (y) is any one of aspects (a) to (x), wherein the glass article comprises a normalized deflection obtained by deflection (in mm) × thickness (in mm) × modulus of elasticity (in Pa), the normalized deflection being greater than or equal to 80 (10^9 N or GN), or greater than or equal to 100 (10^9 N or GN), or greater than or equal to 120 (10^9 N or GN), greater than or equal to 140 (10^9 N or GN), or greater than or equal to 150 (10^9 N or GN).

[0113] glass substrate

[0114] Examples of glasses that can be used as substrates may include soda-lime silicate glass compositions, alkali aluminosilicate glass compositions, or alkali aluminoborosilicate glass compositions, but other glass compositions, such as soda-lime silicate glass, are also contemplated. Specific examples of glass substrates that can be used include, but are not limited to, soda-lime silicate glass, alkali aluminosilicate glass, alkali borosilicate glass, alkali aluminoborosilicate glass, or alkali phosphate glass. In one embodiment, the glass substrate comprises an alkali lithium aluminosilicate composition. The glass substrate has a base composition that can be characterized as ion-exchangeable. As used herein, "ion-exchangeable" means that the substrate containing the composition is capable of exchanging cations located on or near the surface of the substrate with cations of larger or smaller sizes having the same valence. In some embodiments, the alkali content of the glass substrate is greater than 2 mol%.

[0115] In one or more embodiments, the glass substrate may include lithium aluminum silicate. In one embodiment, the Na2O / Li2O molar ratio of the glass substrate is in the range of greater than or equal to 1.5 and less than or equal to 2.1, including all values ​​and ranges therebetween, including greater than or equal to 1.8 and less than or equal to 2.0.

[0116] In one embodiment, the glass substrate comprises a central composition comprising: about 50 mol% to about 69 mol% SiO2; about 12.5 mol% to about 25 mol% Al2O3; about 11.0 mol% to about 15.0 mol% Na2O; about 0.5 mol% to about 10 mol% Li2O; and about 0.01 mol% to about 2 mol% K2O. In some embodiments, the glass substrate further comprises one or more of the following components: about 0 mol% to about 8 mol% B2O3; about 0.5 mol% to about 2 mol% CaO; about 0.5 mol% to about 2 mol% MgO; about 0.1 mol% to about 1 mol% ZnO; about 0.1 mol% to about 0.5 mol% SnO2; about 0 mol% to about 0.1 mol% TiO2; about 0 mol% to about 0.1 mol% Fe2O3; about 0 mol% to about 0.1 mol% P2O5; about 0 mol% to about 0.1 mol% ZrO2; and about 0 mol% to about 0.1 mol% MnO2.

[0117] In some embodiments, the glass substrate can be formed from any composition capable of forming a stress distribution. In some embodiments, the glass substrate can be formed from the glass composition described in U.S. Application No. 16 / 202,691, filed November 28, 2018, entitled “Glasses with Low Excess Modifier Content,” the entire contents of which are incorporated herein by reference. In some embodiments, the glass article can be formed from the glass composition described in U.S. Application No. 16 / 202,767, filed November 28, 2018, entitled “Ion-Exchangeable Mixed Alkali Aluminosilicate Glasses,” the entire contents of which are incorporated herein by reference.

[0118] The glass substrate is characterized by the manner in which it can be formed. For ease of implementation, the glass substrate can be characterized as float-forming (i.e., formed by a float process), draw-down, particularly fusion-forming, or slot-drawing (i.e., formed by a draw-down process, such as a fusion-drawing process or a slot-drawing process). In embodiments, the glass substrate can be rolled.

[0119] Some embodiments of the glass substrates described herein can be formed using a downward drawing process. The overflow downward drawing process produces glass substrates with a relatively uniform thickness and a surface relative to the original surface. Because the average flexural strength of a glass article is controlled by the amount and size of surface defects, the original surface with the least contact has higher initial strength. Furthermore, overflow downward-drawn glass articles have a very smooth surface, eliminating the need for expensive grinding and polishing before use in their final applications.

[0120] Some embodiments of glass substrates can be described as fusion-forming (i.e., forming using a fusion drawing process). The fusion process is an overflow-downward drawing process using a drawing groove with channels for receiving molten glass feedstock. The channels have weirs that open at the top along the length of the channel on both sides. When the channel is filled with molten material, the molten glass overflows the weirs. Due to gravity, the molten glass flows down the outer surfaces of the drawing groove as two flowing glass films. These outer surfaces of the drawing groove extend downwards and inwards, causing them to fuse at the lower edge of the drawing groove. The two flowing glass films fuse at this edge, forming a single flowing glass article. The advantage offered by fusion drawing is that because the two glass films flowing through the channel are fused together, the outer surface of the resulting glass article does not come into contact with any part of the equipment. Therefore, such contact does not affect the surface properties of the fusion-drawn glass article.

[0121] Some embodiments of the glass substrates described herein can be formed using a slot drawing process. Slot drawing differs from fusion drawing. In slot drawing, molten raw glass is fed into a drawing tank. The bottom of the drawing tank has an open slot with nozzles extending the length of the slot. The molten glass flows through the slot / nozzle and is drawn downwards as a continuous glass article into the annealing region.

[0122] In one or more embodiments, the glass substrates described herein may exhibit an amorphous microstructure and may be substantially free of crystals or microcrystals. In other words, in some embodiments, the glass substrates and glass articles do not include glass-ceramic materials.

[0123] Terminal products

[0124] The glass articles disclosed herein can be incorporated into another article, such as articles having a display (or display articles) (e.g., consumer electronics, including mobile phones, tablets, computers, navigation systems, etc.); building articles; transportation articles (e.g., automobiles, trains, airplanes, ships, etc.); electrical articles; defense articles; medical articles, packaging articles and safety articles; or any article that may benefit from a certain degree of transparency, scratch resistance, abrasion resistance or a combination thereof. Figure 2A and 2BThe document illustrates exemplary articles comprising any of the glass articles disclosed herein. Specifically, Figure 2A and 2B A consumer electronic device 200 is shown, comprising a housing 202 having a front surface 204, a rear surface 206, and a side surface 208; electrical components (not shown) at least partially or entirely within the housing, including at least a controller, memory, and a display 210 located at or adjacent to the front surface of the housing; and a cover 212 located at or above the front surface of the housing, such that it is above the display. In some embodiments, the cover 212 and / or the housing 202 may comprise any of the glass articles disclosed herein.

[0125] Example

[0126] The various implementation schemes will be further illustrated by the following examples. Different DOL targets were designed for the experiments. In these examples, "DOL" refers to the DOL as reported by the FSM. The target DOL for Examples 1 and 2-I is in the range of approximately 30 micrometers to approximately 35 micrometers. The target DOL for Examples 4 and 5 is in the range of approximately 65 micrometers to approximately 70 micrometers. The target DOL for Example 6 is in the range of approximately 85 micrometers to approximately 90 micrometers.

[0127] Ion exchange was performed on glass substrates with composition I and a thickness of 0.8 mm under various conditions, including a series of three ion exchange (TIOX) baths, summarized in Table 1. Ion exchange was also performed on glass substrates with composition I and a thickness of 0.8 mm under comparative conditions: using a single ion exchange (SIOX) bath or a double ion exchange (DIOX) bath, summarized in Table 1. The goal of the TIOX conditions was to produce glass articles with higher preload compressive stress CS compared to comparative articles, in order to improve the likelihood of survival in high-stress impact events. All of these substrates utilized a 2D configuration without any 3D thermal history.

[0128] Table 1

[0129]

[0130] Composition I has the following components: 0.03 mol% K₂O; 11.73 mol% Na₂O; 5.83 mol% Li₂O; 18.52 mol% Al₂O₃; 59.16 mol% SiO₂; 1.71 mol% CaO; 1.87 mol% MgO; 0.91 mol% ZnO; 0.11 mol% SnO₂; 0.06 mol% TiO₂; 0.02 mol% Fe₂O₃; 0.02 mol% B₂O₃; 0.01 mol% P₂O₅; 0.01 mol% ZrO₂; 0.01 mol% MnO₂ (0.00 mol% SrO); and a Na₂O / Li₂O molar ratio of 2.

[0131] The various stress distribution parameters of the obtained products are summarized in Table 2. Table 2 shows the stress distribution parameters for CS. max The DOL and CT values ​​were measured at 598 nm using the FSM, and the SOC value was measured at 546 nm. This typically results in an approximately 0.8% underreporting of Csmax compared to the SOC value at 598 nm (which is an appropriate value to match the FSM measurement wavelength). Therefore, referring to Table 2, the actual values ​​of Csmax, CT, and Kt will be expected to be approximately 0.8% higher than the reported values. DOL / t is calculated. Kt is the tensile stress factor discussed in this paper, derived from the FSM distribution.

[0132] Table 2

[0133]

[0134] Figure 5This is a graph showing the concentrations (mol%) of K₂O, Na₂O, and Li₂O versus depth (µm) for Example 2-I. As shown in Table 1, the TIOX conditions were: Step 1 (S1): 100 wt% KNO₃ at 410 °C for 25 hr; Step 2 (S2): 30 wt% KNO₃ / 70 wt% NaNO₃ at 430 °C for 1 hr; and Step 3 (S3): 95 wt% KNO₃ / 5 wt% K₂CO₃ at 385 °C for 8 hr. Most of the ion exchange occurred within a depth of approximately 30 µm via K↔Na ion exchange. Step 1 of the K↔Na ion exchange produced a K₂O concentration distribution at a depth of approximately 28 µm, with a surface concentration of approximately 13 mol%. After Step 2, via Na↔K ion exchange, the surface concentration of K₂O decreased from approximately 13 mol% to approximately 3.5 mol%, while the surface concentration of Na₂O increased from approximately 2 mol% to approximately 14 mol%. The depth of Na↔K ion exchange in this step is approximately 15 µm. Some Na↔Li ion exchange also occurs in this step, which significantly influences the Li cation distribution at a depth of approximately 30 µm. After step 3, the surface concentration increases to approximately 15 mol%, which is even higher than the level after step 1 (approximately 13 mol%). The K₂O distribution depth after step 3 is approximately 31 µm, which is deeper than the depth after step 1, indicating higher CS and deeper DOL, a fact confirmed by FSM and modeling data.

[0135] Figure 6 The graphs show the modeling analysis performed by modeling diffusion at normalized location (z / thickness) with stress (MPa) for various examples in Table 1. Table 3 summarizes the various parameters generated by the modeling. For concentration distribution, the modeling analysis estimate is typically higher than that of surface stress (e.g., CS). max More accurate. The simulated stress distributions in Examples 1 and 2-I show that TIOX can produce a much higher CS than SIOX with a similar DOL, and a much deeper DOL with a higher CS than DIOX.

[0136] Table 3

[0137]

[0138] Figure 7 This is a graph of compressive stress (MPa) versus thickness (micrometers) for Example 1. Figure 8 Provided based on Figure 7 Example 1 shows a graph of compressive stress integral (MPa•mm) versus thickness (micrometers).

[0139] Figure 9 A graph of compressive stress (MPa) versus thickness (micrometers) is provided for Example 2-II. Figure 10 Provided based on Figure 9 Example 2-II shows the A(z) plot of the compressive stress integral (MPa•mm) against the thickness (micrometers).

[0140] Figure 11 This is a graph of compressive stress (MPa) versus thickness (micrometers) for Example 3. Figure 12 Provided based on Figure 11 Example 3 shows a graph of compressive stress integral (MPa•mm) versus thickness (micrometers).

[0141] Figure 7 , 9 The stress distributions for 11 and 11 are near-surface distributions obtained by the inverse IWKB method according to the stepwise linear IWKB method of U.S. Patent No. 9,140,543, which is incorporated herein by reference in its entirety. The deeper ends of the IWKB distribution exhibit a reduced signal-to-noise ratio, which does not significantly affect the accuracy of the DOC or the A(z) value, especially for z ≤ DOC. However, associated with the limited resolution of IWKB-based stress distribution extraction, the surface CS can potentially vary on the order of 10–20 MPa.

[0142] Table 4.A provides examples 2-II and 3 of CS based on IWKB-based surface distribution reports. max DOC / t. CT (MPa) and Kt were calculated according to U.S. Patent No. 11,639,310, based on the IWKB-based surface distribution and method, which is incorporated herein by reference in its entirety. DOC / t was calculated. The DOL value was obtained from the FSM measured at 598 nm. DOL / t was calculated. Table 4.B provides the compressive stress integrals at different depths for Examples 1, 2-II, and 3, where z = 5 µm, 8 µm, 12 µm, 16 µm, 20 µm, and 25 µm, which include... Figure 8 , 10 The A(z) graph (MPa*mm versus thickness (µm)) for 12 is shown.

[0143] Table 4.A

[0144]

[0145] Table 4.B

[0146]

[0147] Analyze the wear RoR comparison of Example 1 and Comparative Example B (0.5-inch diameter loading ring and 1-inch diameter support ring).

[0148] For abrasion, pneumatic abrasion was used to damage the glass samples. Before abrasion, the samples were covered with masking tape having a 1 / 8-inch diameter hole at the center. Therefore, the abrasion area was confined to a 1 / 8-inch circular spot at the center of the sample. 90-fineness SiC was used as the abrasive material. Various pressures ranging from 1 psi to 15 psi were used to create defects of different depths. The abraded samples were tested using RoR at 23°C and 50% RH for 12 hours.

[0149] For the determination of residual strength / failure stress and the measurement of defect depth, assess the failure stress from the measured failure load using the details provided in ASTM C1499-19 and Example 7 below. Preserve the fractured sample and perform fractography. Isolate the failure source and measure the defect depth (inspection depth or crack tip depth). Figure 13 The graph shows the relationship between failure stress (MPa) and defect depth (micrometers).

[0150] Compared to Comparative Example B, Example 1 exhibits significantly higher failure stress at deeper defect depths (2 µm to 25 µm) (almost twice as high at a 9 µm defect depth). Defect depths seen in this range are typical for such applications and similar MCE (Mobile Consumer Electronics) applications.

[0151] Figure 14 This is a graph of the failure probability (%) versus failure stress (MPa) for Example 1. Using the details provided in ASTM C1499-19 and Example 7 below, the characteristic strength of Example 1 (63.2% failure probability in a 2-parameter Weibull distribution) is 2.4 GPa under quasi-static conditions and 2.6 GPa under dynamic conditions.

[0152] Example 7. Subsequently, the surface of a glass substrate having composition I and a thickness of 0.8 mm, which has undergone ion exchange according to Example 1, is etched.

[0153] The isoaxial biaxial deflection or ring-on-ring test, as described in Example 7 of ASTM C1499-19 (Isoaxial Biaxial Deflection (RoR) using a 0.5-inch and a 1-inch diameter loading and support rings, respectively), is performed using a device comprising a support ring and a loading ring, with the load applied to the loading ring and the sample positioned between the support ring and the loading ring. For quasi-static conditions, the strain rate ἑ = 0.003 / s, and the displacement rate... = 1.2 mm / min. For both dynamic and static conditions, the strain rate ἑ = 38.5 / s, and the displacement rate... = 1300 mm / s.

[0154] Isobiaxial strength or failure stress:

[0155]

[0156]

[0157] F is the fracture load in N; D L ν is the diameter of the loading ring; D is Poisson's ratio; s The diameter of the support ring is in mm; E is the elastic modulus in MPa; h is the thickness of the test sample; l1 and l2 are the lengths of the edges.

[0158] Figure 15 This is a graph of the failure probability (%) versus failure stress (MPa) for Example 7. The characteristic strength of Example 7 (63.2% failure probability in a 2-parameter Weibull distribution) is 6.5 GPa under quasi-static conditions and 8.7 GPa under dynamic conditions.

[0159] Figure 16 This is the load-deflection plot for Example 7. The deflection is:

[0160]

[0161] Example 7 showed significant deflection during the RoR test (almost three times its thickness).

[0162] Figure 17 This is a normalized load-deflection plot for Example 7 relative to deflection * thickness * modulus of elasticity. The load is greater than 140 relative to deflection * thickness * modulus of elasticity. This material can withstand significant bending during use case events such as drops.

[0163] Examples 1 and 7 represent one aspect of this document, which includes: peak compressive stress (CS) in the peak region. maxThe peak compressive stress is greater than or equal to 1000 MPa, including greater than or equal to 1100 MPa, greater than or equal to 1200 MPa, greater than or equal to 1300 MPa, greater than or equal to 1400 MPa, or greater than or equal to 1500 MPa; and / or the compressive stress integral at a depth of 5 micrometers, the compressive stress integral being greater than or equal to 5.2 MPa·mm; and / or t being in the range of 0.30 mm to 1.5 mm; and / or DOC being greater than or equal to 0.035·t; and / or the characteristic strength, the characteristic strength according to ASTM C1499-19 using a 0.5-inch diameter loading ring and a 1-inch diameter support ring, under quasi-static conditions, in a 2-parameter Weibull distribution, at a failure probability of 63.2%, being greater than or equal to 1.5 GPa to less than or equal to 8 GPa, and / or according to ASTM C1499-19 uses a 0.5-inch diameter loading ring and a 1-inch diameter support ring, under dynamic conditions, in a 2-parameter Weibull distribution, at a failure probability of 63.2%, greater than or equal to 1.5 GPa to less than or equal to 10 GPa; and / or a normalized deflection obtained from deflection (in mm) x thickness (in mm) x elastic modulus (in Pa), said normalized deflection being greater than or equal to 80 (10^9 N or GN), greater than or equal to 100 (10^9 N or GN), or greater than or equal to 120 (10^9 N or GN), greater than or equal to 140 (10^9 N or GN), or greater than or equal to 150 (10^9 N or GN).

[0164] Unless otherwise stated, all compositional components, relationships, and ratios described in this specification are provided in mol%. All scopes disclosed in this specification include any and all scopes and subscopes covered by the broadly disclosed scope, whether explicitly stated before or after the scope disclosure.

[0165] It will be apparent to those skilled in the art that various modifications and variations can be made to the embodiments described herein without departing from the spirit and scope of the claimed subject matter. Therefore, this specification is intended to cover modifications and variations to the various embodiments described herein, provided that such modifications and variations fall within the scope of the appended claims and their equivalents.

Claims

1. A glass article comprising: Opposite first and second surfaces, which define the body of the article having a thickness (t); The stress distribution of the main body, the stress distribution comprising: A peak region extending from the first surface to the inflection point (knee) at the layer depth (DOL). The peak compressive stress (CS) in the peak region max The peak compressive stress is greater than or equal to 1000 MPa; A tail region extending from the inflection point to the center of the glass article, the tail region having central tension (CT) and including depth of compression (DOC); and The compressive stress integral at a depth of 5 micrometers, wherein the compressive stress integral is greater than or equal to 5.2 MPa•mm.

2. The glass article according to claim 1, wherein t is in the range of 0.30 mm to 1.5 mm, and / or the DOC is greater than or equal to 0.035•t.

3. The glass article according to claim 1 or claim 2, comprising one or more of the following: The integral of the compressive stress at a depth of 8 micrometers is greater than or equal to 8.5 MPa·mm; the integral of the compressive stress at a depth of 12 micrometers is greater than or equal to 11.7 MPa·mm; The integral of the compressive stress at a depth of 16 micrometers is greater than or equal to 14.1 MPa·mm; The integral of the compressive stress at a depth of 20 micrometers is greater than or equal to 15.7 MPa·mm; and The integral of the compressive stress at a depth of 25 micrometers is greater than or equal to 16.7 MPa•mm.

4. A glass article comprising: Opposite first and second surfaces, the opposite first and second surfaces defining the body of the article with a thickness (t) greater than or equal to 0.70 mm and less than or equal to 1.3 mm; The stress distribution of the main body, the stress distribution comprising: A spike region extending from the first surface to an inflection point at a layer depth (DOL) greater than or equal to 20 micrometers; The peak compressive stress (CS) in the peak region max The peak compressive stress is greater than or equal to 1000 MPa; and A tail region extending from the inflection point to the center of the glass article, the tail region having center tension (CT) and including a depth of compression (DOC) greater than or equal to 25 micrometers.

5. The glass article of claim 4, comprising a compressive stress integral at a depth of 5 micrometers, said compressive stress integral being greater than or equal to 5.2 MPa·mm, and optionally including one or more of the following: The integral of the compressive stress at a depth of 8 micrometers is greater than or equal to 8.5 MPa·mm; The integral of the compressive stress at a depth of 12 micrometers is greater than or equal to 11.7 MPa·mm; The integral of the compressive stress at a depth of 16 micrometers is greater than or equal to 14.1 MPa·mm; The integral of the compressive stress at a depth of 20 micrometers is greater than or equal to 15.7 MPa·mm; and The integral of the compressive stress at a depth of 25 micrometers is greater than or equal to 16.7 MPa•mm.

6. The glass article according to any one of claims 1 to 5, comprising a 3D configuration.

7. The glass article according to any one of claims 1 to 6, wherein the peak compressive stress (CS) in the peak region is... max ) Greater than or equal to 1100 MPa, 1200 MPa, 1300 MPa, 1400 MPa or 1500 MPa.

8. The glass article according to any one of claims 1 to 7, comprising a lithium aluminum silicate core composition, and optionally, wherein the Na2O / Li2O molar ratio of said lithium aluminum silicate core composition is in the range of greater than or equal to 1.5 to less than or equal to 2.

1.

9. The glass article according to claim 8, wherein the lithium aluminum silicate core composition comprises: Approximately 50 mol% to approximately 69 mol% SiO2; Approximately 12.5 mol% to approximately 25 mol% Al2O3; Approximately 0 mol% to approximately 8 mol% B2O3; Approximately 0.01 mol% to approximately 2 mol% K₂O; Approximately 11.0 mol% to approximately 15.0 mol% Na₂O; and Approximately 0.5 mol% to approximately 10 mol% Li₂O.

10. The glass article according to any one of claims 1 to 9, comprising: one or more of the following, when tested according to ASTM C1499-19 using a loading ring of 0.5 inches in diameter and a support ring of 1 inch in diameter: At a defect depth of 5 micrometers, the failure stress is greater than or equal to 1500 MPa, greater than or equal to 1600 MPa, greater than or equal to 1700 MPa, greater than or equal to 1800 MPa, or greater than or equal to 1900 MPa. At a defect depth of 9 micrometers, the failure stress is greater than or equal to 1200 MPa, or greater than or equal to 1300 MPa, or greater than or equal to 1400 MPa, or greater than or equal to 1500 MPa, or greater than or equal to 1600 MPa. At a defect depth of 13 micrometers, the failure stress is greater than or equal to 600 MPa, greater than or equal to 700 MPa, greater than or equal to 800 MPa, or greater than or equal to 900 MPa. as well as At a defect depth of 25 micrometers, the failure stress is greater than or equal to 400 MPa or greater than or equal to 500 MPa.

11. The glass article according to any one of claims 1 to 10, comprising: a characteristic strength of greater than or equal to 1.5 GPa to less than or equal to 8 GPa under quasi-static conditions, in a two-parameter Weibull distribution, with a failure probability of 63.2%, using a loading ring of 0.5 inches in diameter and a support ring of 1 inch in diameter according to ASTM C1499-19; and / or a characteristic strength of greater than or equal to 1.5 GPa to less than or equal to 10 GPa under dynamic conditions, in a two-parameter Weibull distribution, with a failure probability of 63.2%, using a loading ring of 0.5 inches in diameter and a support ring of 1 inch in diameter according to ASTM C1499-19.

12. The glass article of claim 11, in the absence of surface etching, comprises: a characteristic strength of greater than or equal to 1.5 GPa and less than or equal to 4 GPa under quasi-static and / or dynamic conditions, using a loading ring of 0.5 inches in diameter and a support ring of 1 inch in diameter according to ASTM C1499-19.

13. The glass article of claim 11, further combined with surface etching, the glass article comprising: a characteristic strength of greater than or equal to 4 GPa to less than or equal to 8, including greater than or equal to 6.5 GPa, under quasi-static conditions, in a two-parameter Weibull distribution with a failure probability of 63.2%, using a loading ring of 0.5 inches in diameter and a support ring of 1 inch in diameter according to ASTM C1499-19; and / or a characteristic strength of greater than or equal to 5 GPa to less than or equal to 10, including greater than or equal to 8.7 GPa, under dynamic conditions, in a two-parameter Weibull distribution with a failure probability of 63.2%.

14. The glass article according to any one of claims 1 to 13, comprising a normalized deflection obtained by deflection × thickness × modulus of elasticity, said normalized deflection being greater than or equal to 80 GN, greater than or equal to 100 GN, greater than or equal to 120 GN, greater than or equal to 140 GN, or greater than or equal to 150 GN.

15. A consumer electronics product comprising: The housing has a front surface, a rear surface, and side surfaces; Electrical components, at least partially disposed within the housing, the electrical components including at least a controller, a memory, and a display, the display being disposed on or adjacent to the front surface of the housing; as well as The glass article according to any one of claims 1 to 14 is disposed above the display.

16. A method of manufacturing a glass article having opposing first and second surfaces, the opposing first and second surfaces defining a body having a thickness (t), the method comprising: The glass substrate is exposed to a first ion exchange (IOX-1) treatment for a first duration at a first temperature below the strain point of the glass substrate containing alkali metal oxides in the base composition, the IOX-1 treatment comprising a first bath containing one or more molten potassium salts. Following the first IOX-1, the glass substrate is exposed to a second ion exchange (IOX-2) treatment for a second duration at a second temperature greater than or equal to the first temperature and less than the strain point. The IOX-2 treatment includes a second bath comprising a mixture of ion-exchangeable molten salts and optional scavenging additives. The second duration is shorter than the first duration. Following the IOX-2, the glass substrate is exposed to a third ion exchange (IOX-3) treatment for a third duration at a third temperature lower than the first temperature. The IOX-3 treatment includes a third bath containing one or more molten potassium salts, and the third duration is shorter than the first duration.

17. The method of claim 16, wherein: The first bath contains greater than or equal to 90% by weight potassium nitrate (KNO3) and less than or equal to 10% by weight sodium nitrate (NaNO3). The mixture of the ion-exchangeable molten salt in the second bath comprises potassium nitrate (KNO3) and sodium nitrate (NaNO3), and the sodium to potassium (Na:K) ratio is greater than 1; and The third bath comprises: 0 to less than or equal to 15% by weight of potassium carbonate (K₂CO₃) and potassium nitrate (KNO₃), reaching a total of 100 wt.%. and / or The first duration is greater than or equal to 5 hours and less than or equal to 50 hours; The second duration is greater than or equal to 0.5 hours and less than or equal to 2 hours; and The third duration is greater than or equal to 1 hour and less than 15 hours. and / or The first temperature is greater than or equal to 400°C and less than or equal to 500°C; The second temperature is greater than or equal to 400°C and less than or equal to 550°C; and The third temperature is greater than or equal to 350°C and less than 450°C.

18. The method of claim 16, wherein the second bath comprises: greater than or equal to 5% by weight to less than or equal to 45% by weight of potassium nitrate (KNO3) and greater than or equal to 55% by weight to less than or equal to 95% by weight of sodium nitrate (NaNO3), reaching a total of 100 wt.%.

19. The method of claim 16, wherein it does not include any thermal relaxation step performed in the absence of a molten salt bath between the IOX-1 and the IOX-3.

20. The method of claim 16, wherein the glass substrate comprises: a sodium-calcium silicate composition; an alkali aluminosilicate composition; an alkali borosilicate composition; an alkali aluminoborosilicate composition or an alkali phosphate composition, optionally wherein the glass substrate comprises a core composition comprising: a Na₂O / Li₂O molar ratio in the range of greater than or equal to 1.5 to less than or equal to 2.1, and / or: Approximately 50 mol% to approximately 69 mol% SiO2; Approximately 12.5 mol% to approximately 25 mol% Al2O3; Approximately 0 mol% to approximately 8 mol% B2O3; Approximately 0.01 mol% to approximately 2 mol% K₂O; Approximately 11.0 mol% to approximately 15.0 mol% Na₂O; and Approximately 0.5 mol% to approximately 10 mol% Li₂O.

Images