Glass with improved drop performance

Abstract

Glass-based articles are provided that exhibit improved drop performance.Relationships are provided between properties attributable to glass compositions and stress profiles of glass-based articles that exhibit improved drop performance.

Description

Description of Related Applications

[0001] This application claims the benefit of priority under 35 U.S.C. §119 of U.S. Provisional Patent Application No. 62 / 678,560, filed May 31, 2018, the contents of which are relied upon and incorporated herein by reference in their entirety. [Technical Field]

[0002] FIELD OF THE INVENTION This specification relates generally to glass compositions suitable for use as cover glasses for electronic devices. [Background technology]

[0003] Due to the portable nature of portable devices such as smartphones, tablets, portable media players, personal computers, and cameras, these devices are particularly susceptible to accidental drops onto hard surfaces, such as the ground. These devices typically incorporate a cover glass, which can be damaged when struck by a hard surface. In many of these devices, the cover glass serves as a cover for the display and may provide touch functionality; therefore, use of such devices is adversely affected when the cover glass is damaged.

[0004] There are two primary modes of cover glass failure when the associated portable device is dropped onto a hard surface. One mode is flexural failure, which occurs due to bending of the glass when the device is subjected to dynamic loads from impact with the hard surface. The other mode is sharp contact failure, which occurs due to the introduction of damage into the glass surface. When glass impacts a rough hard surface, such as asphalt or granite, sharp indentations can occur in the glass surface. These indentations become fracture sites in the glass surface from which cracks can initiate and propagate.

[0005] Glass can be made more resistant to flexural failure by ion-exchange techniques, which involve introducing compressive stress into the glass surface. However, ion-exchanged glass is still vulnerable to dynamic sharp contact due to high stress concentrations caused by localized indentations in the glass from the sharp contact.

[0006] Glass manufacturers and portable device manufacturers have continually strived to improve the resistance of portable devices to sharp contact damage. Solutions range from coatings on the cover glass to bezels that prevent the cover glass from directly impacting a hard surface when the device is dropped onto it. However, due to constraints of aesthetic and functional requirements, it is very difficult to completely prevent the cover glass from impacting a hard surface.

[0007] It is also desirable to make portable devices as thin as possible. Therefore, in addition to strength, it is also desirable to make the glass to be used as a cover glass in a portable device as thin as possible. Therefore, in addition to increasing the strength of the cover glass, it is also desirable for the glass to have mechanical characteristics that allow it to be formed by processes that can produce thin glass articles, such as thin glass sheets. Summary of the Invention [Problem to be solved by the invention]

[0008] Thus, there is a need for glasses that can be strengthened, such as by ion exchange, and that have mechanical properties that allow the glass to be formed into thin glass articles. [Means for solving the problem]

[0009] According to embodiment (1), a glass-based article is provided. The glass-based article includes a compressive stress layer extending from the surface of the glass-based article to a compression depth. The glass-based article is a K IC 2 ×DOC / t×√STE≧7.0×10 11 Pa 2.5 m 1.5wherein K IC is the Pa·m of a glass-based substrate with the same composition and phase assemblage as those at the center of the glass-based article. 0.5 where DOC is the compression depth in metres, t is the thickness of the glass-based article in metres, and STE is the stored strain energy of the glass-based article in Pa·m.

[0010] According to aspect (2), K IC 2 ×DOC / t×√STE≧8.0×10 11 Pa 2.5 m 1.5 The glass-based article of embodiment (1) is provided, wherein

[0011] According to aspect (3), K IC 2 ×DOC / t×√STE≧9.0×10 11 Pa 2.5 m 1.5 The glass-based article of embodiment (1) or (2) is provided, wherein:

[0012] According to aspect (4), K IC 2 ×DOC / t×√STE≧9.5×10 11 Pa 2.5 m 1.5 The glass-based article of any of aspects (1) to (3) is provided, wherein

[0013] According to aspect (5), K IC 2 ×DOC / t×√STE≧1.0×10 12 Pa 2.5 m 1.5 The glass-based article of any of aspects (1) to (4) is provided, wherein

[0014] According to embodiment (6), a glass-based article is provided. The glass-based article includes a compressive stress layer extending from the surface of the glass-based article to a compression depth. The glass-based article is a K IC 2 ×DOC×√STE≧5.6×108 Pa 2.5 m 2.5 wherein K IC is the Pa·m of a glass-based substrate with the same composition and phase assemblage as those at the center of the glass-based article. 0.5 where DOC is the compression depth in metres, t is the thickness of the glass-based article in metres, and STE is the stored strain energy of the glass-based article in Pa·m.

[0015] According to aspect (7), K IC 2 ×DOC×√STE≧6.0×10 8 Pa 2.5 m 2.5 The glass-based article of embodiment (6) is provided, wherein

[0016] According to aspect (8), K IC 2 ×DOC×√STE≧7.0×10 8 Pa 2.5 m 2.5 The glass-based article of embodiment (6) or (7) is provided, wherein

[0017] According to aspect (9), K IC 2 ×DOC×√STE≧8.0×10 8 Pa 2.5 m 2.5 The glass-based article of any of aspects (6) to (8) is provided, wherein

[0018] According to a tenth aspect, a glass-based article is provided. The glass-based article includes a compressive stress layer extending from a surface of the glass-based article to a compression depth. The glass-based article is a K IC 2 ×DOC×H / E×√STE≧4.1×10 7 Pa 2.5 m 2.5 wherein K IC is the Pa·m of a glass-based substrate with the same composition and phase assemblage as those at the center of the glass-based article. 0.5where DOC is the compression depth in meters, H is the hardness in Pascals of a glass-based substrate having a composition and phase assemblage equal to that at the center of the glass-based article, E is the Young's modulus in Pascals of a glass-based substrate having a composition and phase assemblage equal to that at the center of the glass-based article, and STE is the stored strain energy of the glass-based article in Pa·m.

[0019] According to aspect (11), K IC 2 ×DOC×H / E×√STE≧4.5×10 7 Pa 2.5 m 2.5 The glass-based article of embodiment (10) is provided, wherein

[0020] According to aspect (12), K IC 2 ×DOC×H / E×√STE≧5.0×10 7 Pa 2.5 m 2.5 The glass-based article of embodiment (10) or (11) is provided, wherein

[0021] According to aspect (13), K IC 2 ×DOC×H / E×√STE≧5.5×10 7 Pa 2.5 m 2.5 The glass-based article of any of aspects (10) to (12) is provided, wherein

[0022] According to an aspect (14), there is provided the glass-based article of any of the previous aspects, wherein DOC≧75 μm.

[0023] According to an aspect (15), there is provided the glass-based article of any of the previous aspects, wherein the DOC is ≦300 μm.

[0024] According to an aspect (16), there is provided the glass-based article of any of the previous aspects, wherein DOC≦0.4t.

[0025] According to an aspect (17), there is provided the glass-based article of any of the previous aspects, wherein DOC≧0.1t.

[0026] According to an aspect (18), there is provided the glass-based article of any of the previous aspects, having a maximum central tension CT of 95 MPa or greater.

[0027] According to an aspect (19), there is provided the glass-based article of any of the previous aspects, having a maximum central tension CT of 120 / √t MPa or less, where t is expressed in mm.

[0028] According to an aspect (20), there is provided the glass-based article of any of the previous aspects, wherein the glass-based article has a thickness t of 1.0 mm or less.

[0029] According to an aspect (21), there is provided the glass-based article of any of the previous aspects, wherein the glass-based article has a thickness t of 0.3 mm or greater.

[0030] According to an aspect (22), there is provided the glass-based article of any of the previous aspects, wherein STE is ≧20 Pa·m.

[0031] According to an embodiment (23), there is provided the glass-based article of any one of embodiments (1) to (21), wherein 5 Pa·m≦STE≦10 Pa·m.

[0032] According to an embodiment (24), there is provided the glass-based article of any of the previous embodiments, wherein the compressive stress layer has a compressive stress CS of 100 MPa or more.

[0033] According to an embodiment (25), there is provided the glass-based article of any of the previous embodiments, wherein the compressive stress layer has a compressive stress CS of 400 MPa or more.

[0034] According to an embodiment (26), there is provided the glass-based article of any of the previous embodiments, wherein the compressive stress layer has a compressive stress CS of 1300 MPa or less.

[0035] According to aspect (27), there is provided the glass-based article of any of the previous aspects, wherein the glass-based article is made from a glass-ceramic.

[0036] According to an aspect (28), there is provided the glass-based article of any of the previous aspects, wherein the glass-based article comprises SiO, AlO, BO, and at least one alkali metal oxide.

[0037] According to aspect (29), a glass-based substrate having a composition and a phase set equal to the composition and the phase set at the center of the glass-based article has a K of 0.75 MPa√m or more. IC The glass-based article of any of the previous aspects is provided, having:

[0038] According to aspect (30), a glass-based substrate having a composition and a phase set equal to the composition and the phase set at the center of the glass-based article has a K of 1.5 MPa√m or less. IC The glass-based article of any of the previous aspects is provided, having:

[0039] According to an aspect (31), there is provided the glass-based article of any of the previous aspects, wherein the glass-based substrate having a composition and phase assemblage equal to the composition and phase assemblage at the center of the glass-based article has a hardness H of 6.0 GPa or greater.

[0040] According to an aspect (32), there is provided the glass-based article of any of the previous aspects, wherein the glass-based substrate having a composition and phase assemblage equal to the composition and phase assemblage at the center of the glass-based article has a hardness H of 8.0 GPa or less.

[0041] According to an aspect (33), there is provided the glass-based article of any of the previous aspects, wherein the glass-based substrate having a composition and phase assemblage equivalent to the composition and phase assemblage at the center of the glass-based article has a Young's modulus, E, of 80 GPa or greater.

[0042] According to an aspect (34), there is provided the glass-based article of any of the previous aspects, wherein the glass-based substrate having a composition and phase assemblage equal to the composition and phase assemblage at the center of the glass-based article has a Young's modulus, E, of 120 GPa or less.

[0043] According to a thirty-fifth aspect, a method is provided, comprising ion-exchanging a glass-based substrate to form a glass-based article having a compressive stress layer extending from a surface of the glass-based article to a compression depth. IC 2 ×DOC / t×√STE≧7.0×10 11 Pa 2.5 m 1.5 wherein K IC is the Pa·m of the glass substrate 0.5 where DOC is the compression depth in metres, t is the thickness of the glass-based article in metres, and STE is the stored strain energy of the glass-based article in Pa·m.

[0044] According to a thirty-sixth aspect, a method is provided, comprising ion-exchanging a glass-based substrate to form a glass-based article having a compressive stress layer extending from a surface of the glass-based article to a compression depth. IC 2 ×DOC×H / E×√STE≧4.1×10 7 Pa 2.5 m 2.5 wherein K IC is the Pa·m of the glass substrate 0.5 where DOC is the compression depth in meters, H is the hardness of the glass-based substrate in Pascals, E is the Young's modulus of the glass-based substrate in Pascals, and STE is the stored strain energy of the glass-based article in Pa·m.

[0045] According to an embodiment (37), there is provided the method of embodiment (35) or (36), wherein the glass-based substrate is made of glass-ceramic.

[0046] According to an embodiment (38), there is provided the method of any one of embodiments (35) to (37), wherein the ion-exchanging step includes contacting the glass-based substrate with a molten salt bath.

[0047] According to an embodiment (39), there is provided the method of embodiment (38), wherein the molten salt bath includes at least one of sodium nitrate and potassium nitrate.

[0048] According to an embodiment (40), there is provided the method of embodiment (38) or (39), wherein the contacting step lasts for at least 4 hours up to 48 hours.

[0049] According to an embodiment (41), there is provided the method of any of embodiments (38) to (40), wherein during the contacting step, the molten salt bath is at a temperature of 400° C. or more and 500° C. or less.

[0050] According to an aspect (42), there is provided a glass-based article produced by the method of any one of aspects (35) to (41).

[0051] According to aspect (43), there is provided a domestic appliance comprising: a housing having a front, a back, and a side; 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 of the housing; and a cover glass disposed over the display, wherein at least one of a portion of the housing or a portion of the cover glass is made from the glass-based article of any of aspects (1) through (34) or (42).

[0052] Additional features and advantages will be set forth in the following detailed description, and in part will become readily apparent to those skilled in the art from that description, or may be learned by practicing the embodiments described herein, including the following detailed description, claims, and accompanying drawings.

[0053] It will 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 character of the claimed subject matter. The accompanying drawings are included to provide a further understanding of the various embodiments, and are incorporated into and constitute a part of this specification. The drawings illustrate various embodiments described herein, and together with the description, serve to explain the principles and operation of the claimed subject matter. [Brief explanation of the drawings]

[0054] [Figure 1] Schematic of the specimen and its cross section used to determine the fracture toughness KIC [Figure 2] 1 is a cross-sectional view of a glass-based article having a compressive stress layer on a surface thereof according to embodiments disclosed and described herein. [Figure 3A] FIG. 1 is a plan view of an exemplary electronic device incorporating any of the glass-based articles disclosed herein. [Figure 3B] FIG. 3B is a perspective view of the exemplary electronic device of FIG. [Figure 4] Plot of drop performance as a function of the value of formula (I) for various comparative examples and embodiments. [Figure 5] Plot of drop performance as a function of the value of formula (II) for various comparative examples and embodiments. DETAILED DESCRIPTION OF THE INVENTION

[0055] Reference will now be made in detail to glass-based articles according to various embodiments. As used herein, "glass-based" refers to an article comprising glass, such as a glass or glass-ceramic composition. Generally, a "glass-based substrate" refers to the article prior to ion-exchange, and a "glass-based article" refers to the article after ion-exchange.

[0056] The glass-based article exhibits improved drop performance, the glass-based article includes a compressive stress layer extending from the surface of the glass-based article to the compression depth, and the glass-based article exhibits a minimum value of an equation that correlates with desired drop performance based on various properties affected by the glass composition and the compression profile characteristics of the glass-based article.

[0057] In some embodiments, the glass-based article has the following formula (I):

[0058]

number

[0059] wherein K IC is the Pa·m of a glass-based substrate with the same composition and phase assemblage as those at the center of the glass-based article. 0.5 where DOC is the compression depth in meters, t is the thickness of the glass-based article in meters, and STE is the stored tensile energy of the glass-based article in Pa·m. The dependence of equation (I) on the thickness of the glass-based article allows for the comparison of the performance of glass-based articles across different thicknesses. In an embodiment, the glass-based article has a 9.0×10 11 Pa 2.5 m 1.5 That's it, 9.5 x 10 11 Pa 2.5 m 1.5 That's it, 1.0 x 10 12 Pa 2.5 m 1.5 More than or equal to 8.0 x 10 11 Pa 2.5 m 1.5 The values ​​of the above formula (I) may be indicated.

[0060] In some embodiments, the glass-based article has the following formula (IA):

[0061]

number

[0062] wherein K IC is the Pa·m of a glass-based substrate with the same composition and phase assemblage as those at the center of the glass-based article. 0.5 where DOC is the depth of compression in meters, and STE is the stored tensile energy of the glass-based article in Pa m. In an embodiment, the glass-based article has a fracture toughness of 6.5×10 8 Pa 2.5 m 2.5 That's it, 7.5 x 10 8 Pa 2.5 m 2.5 That's it, 8.0 x 10 8 Pa 2.5 m 2.5 More than or equal to 6.0 x 10 8 Pa 2.5 m 2.5 The value of the above formula (IA) may be indicated.

[0063] In some embodiments, the glass-based article has the following formula (II):

[0064]

number

[0065] wherein K IC is the Pa·m of a glass-based substrate with the same composition and phase assemblage as those at the center of the glass-based article. 0.5 where DOC is the depth of compression in meters, H is the hardness in Pascals of a glass-based substrate having a composition and phase assemblage equal to that at the center of the glass-based article, E is the Young's modulus in Pascals of a glass-based substrate having a composition and phase assemblage equal to that at the center of the glass-based article, and STE is the stored tensile strain energy of the glass-based article in Pa·m. In an embodiment, the glass-based article has a tensile strength of 5.0×10 7 Pa 2.5 m 2.5That's it, 5.5 x 10 7 Pa 2.5 m 2.5 More than or equal to, or greater than, 4.5 x 10 7 Pa 2.5 m 2.5 The above formula (II) values ​​may be shown.

[0066] Glass-based articles that satisfy either or both of formulas (I), (IA), and (II) exhibit improved drop performance, a quality that makes the glass-based article particularly suitable for use in electronic devices. Thus, when selecting a glass-based article for use in electronic devices, the effect of the particular combination of properties resulting from the glass composition and the stress profile of the glass-based article will be considered as a whole. IC is included in the equation as an indication of the energy required to propagate a crack, and failure of glass-based articles depends, at least in part, on the propagation of the crack into the tensile region. Drop performance is determined by the K IC The DOC is included in the equation to indicate the depth a crack must propagate to reach the tensile region, with a deeper DOC providing greater fracture resistance by requiring a greater crack propagation depth before reaching the tensile region. The STE is included in the equation to indicate the degree of ion exchange strengthening, which may increase the fracture resistance of the glass-based article. The square root of the STE is incorporated due to the relationship between the square root of the STE and the crushability limit of the glass-based article.

[0067] In formulas (I), (IA), and (II), the properties of a glass-based substrate having a composition and phase assemblage equivalent to that at the center of the glass-based article generally depend on the composition and phase assemblage of the glass-based substrate that was ion-exchanged to form the glass-based article. In practice, the composition and phase assemblage at the center of the glass-based article may be measured by techniques known in the art, and the K of the manufactured glass-based substrate having the measured composition and phase assemblage may be determined. ICThe K, H, and E values ​​will be measured. Additionally, the center of the glass-based article is unaffected or only minimally affected by the ion-exchange process, and thus the composition and phase assemblage at the center of the glass-based article is substantially the same as or the same as the composition of the glass-based substrate. For this reason, the K of the glass-based substrate having the composition and phase assemblage at the center of the glass-based article will be measured. IC The , H, and E values ​​may be determined by measuring these properties of the glass-based substrate before the ion exchange treatment.

[0068] We now discuss the properties of the glass-based article, which can be achieved by varying the amounts of the components of the glass-based composition or the stress profile of the glass-based article.

[0069] The compositions used to form glass-based articles according to embodiments have high fracture toughness (K IC As indicated by equations (I) and (II) above, fracture toughness strongly influences the drop performance of a glass-based article. In some embodiments, the composition used to form the glass-based article has a fracture toughness of 0.76 MPa m 0.5 More than 0.77MPa m 0.5 More than 0.78MPa m 0.5 More than 0.79MPa m 0.5 More than 0.80MPa m 0.5 More than 0.81MPa m 0.5 More than 0.82MPa m 0.5 More than 0.83MPa m 0.5 More than 0.84MPa m 0.5 More than 0.86MPa m 0.5 More than 0.87MPa m 0.5 Above, 0.88MPa m 0.5 More than 0.89MPa m 0.5 More than 0.90MPa m 0.5 More than 0.91MPa m 0.5 More than 0.92MPa m 0.5 More than 0.93MPa m 0.5 More than 0.94MPa m 0.5 More than 0.95MPa m0.5 More than 0.96MPa m 0.5 More than 0.97MPa m 0.5 More than 0.98MPa m 0.5 Over 0.99 MPa m 0.5 More than 1.00MPa m 0.5 More than 1.01MPa m 0.5 Over 1.02 MPa m 0.5 Above, 1.03MPa m 0.5 Over 1.04 MPa m 0.5 More than 1.05MPa m 0.5 More than 1.06MPa m 0.5 More than 1.07MPa m 0.5 More than 1.08MPa m 0.5 Above, 1.09MPa m 0.5 More than 1.10MPa m 0.5 Above, 1.11MPa m 0.5 Above, 1.12MPa m 0.5 Above, 1.13MPa m 0.5 Above, 1.14MPa m 0.5 More than 1.15MPa m 0.5 Above, 1.16MPa m 0.5 Above, 1.17MPa m 0.5 Above, 1.18MPa m 0.5 Above, 1.19MPa m 0.5 More than 1.20MPa m 0.5 Above, 1.21MPa m 0.5 Above, 1.22MPa m 0.5 Above, 1.23MPa m 0.5 Above, 1.24MPa m 0.5 More than 1.25MPa m 0.5 More than 1.26MPa m 0.5 More than 1.27MPa m 0.5 Above, 1.28MPa m 0.5 Above, 1.29MPa m 0.5 More than 1.30MPa m 0.5 Above, 1.31MPa m 0.5 Above, 1.32MPa m 0.5 Above, 1.33MPa m 0.5 or more, or 1.34 MPa m 0.5More than 0.75 MPa m 0.5 More than K IC In embodiments, the composition used to form the glass-based article has a modulus of 0.76 MPa m 0.5 From the above, it is 1.33 MPa m 0.5 Below, 0.77MPa m 0.5 From the above, it is 1.32 MPa m 0.5 Below, 0.78MPa m 0.5 From the above, it is 1.31 MPa m 0.5 Below, 0.79MPa m 0.5 Above 1.30 MPa m 0.5 Below, 0.80MPa m 0.5 From the above, it is 1.29 MPa m 0.5 Below, 0.81MPa m 0.5 From the above, it is 1.28 MPa m 0.5 Below, 0.82MPa m 0.5 From the above, it is 1.27 MPa m 0.5 Below, 0.83MPa m 0.5 From the above, it is 1.26 MPa m 0.5 Below, 0.84MPa m 0.5 Above 1.25 MPa m 0.5 Below, 0.85MPa m 0.5 From the above, it is 1.24 MPa m 0.5 Below, 0.86MPa m 0.5 From the above, it is 1.23 MPa m 0.5 Below, 0.87MPa m 0.5 From the above, it is 1.22 MPa m 0.5 Below, 0.88MPa m 0.5 From the above, it is 1.21 MPa m 0.5 Below, 0.89MPa m 0.5 Above 1.20 MPa m 0.5 Below, 0.90MPa m 0.5 From the above, it is 1.19 MPa m 0.5 Below, 0.91MPa m 0.5 From the above, it is 1.18 MPa m 0.5 Below, 0.92MPa m 0.5 From the above, it is 1.17 MPa m 0.5 Below, 0.93MPa m 0.5 From the above, it is 1.16 MPa m 0.5Below, 0.94MPa m 0.5 Above 1.15 MPa m 0.5 Below, 0.95MPa m 0.5 From the above, it is 1.14 MPa m 0.5 Below, 0.96MPa m 0.5 From the above, it is 1.13 MPa m 0.5 Below, 0.97MPa m 0.5 From the above, it is 1.12 MPa m 0.5 Below, 0.98MPa m 0.5 From the above, it is 1.11 MPa m 0.5 Below, 0.99MPa m 0.5 Above 1.10 MPa m 0.5 Below, 1.00MPa m 0.5 From the above, it is 1.09 MPa m 0.5 Below, 1.01MPa m 0.5 From the above, it is 1.08 MPa m 0.5 Below, 1.02MPa m 0.5 From the above, it is 1.07 MPa m 0.5 Below, 1.03MPa m 0.5 From the above, it is 1.06 MPa m 0.5 Below, 1.04MPa m 0.5 Above 1.05 MPa m 0.5 For example, 0.75 MPa m 0.5 From the above, it is 1.34 MPa m 0.5 All ranges and subranges between the following and preceding values ​​of K IC In some embodiments, the composition used to form the glass-based article has a modulus of 0.90 MPa m 0.5 More than K IC In some embodiments, the composition used to form the glass-based article has a modulus of 1.5 MPa m 0.5 The following K IC Indicates the value.

[0070] As used herein, K IC Fracture toughness is measured by the double cantilever beam (DCB) method. ICThe values ​​were measured on glass-based substrates before they were ion-exchanged to form the glass-based articles. The geometry of the DCB specimen is shown in Figure 1, with the critical parameters being the crack length a, the applied load P, the cross-sectional dimensions w and 2h, and the crack-inducing groove thickness b. The specimens were cut into rectangular shapes with a width 2h = 1.25 cm and a thickness ranging from 0.3 mm to 1 mm. The overall length of the specimens varied from 5 cm to 10 cm, but this is not a critical dimension. Diamond drill holes were drilled at both ends to provide a means for attaching the specimen to a specimen holder and load. Crack "inducing grooves" were cut into both flat surfaces of the specimen using a wafer dicing saw equipped with a diamond blade, running the length of the specimen, leaving a "web" of material approximately half the total thickness of the plate (dimension b in Figure 1) with a height of 180 μm, corresponding to the blade thickness. The dicing saw's high dimensional tolerances minimized sample-to-sample variation. This dicing saw was also used to cut the initial crack with a height of a = 15 mm. This final operation resulted in the formation of a very thin wedge of material near the crack tip (due to the curvature of the blade), making crack initiation within the sample easier. The sample was mounted in a metal sample holder with a steel wire in the hole at the bottom of the sample. To keep the sample horizontal under low load conditions, the sample was supported at the opposite end. A spring in series with a load cell (FUTEK, LSB200) was hooked to the top hole, which was then stretched and gradually loaded using a rope and precision slide. The crack was monitored using a microscope with a 5 μm resolution attached to a digital camera and computer. The following equation (III):

[0071]

number

[0072] Using the applied stress intensity K PFor each specimen, a crack was first initiated at the leading edge of the web, and then the initiating crack was carefully grown subcritically until the dimension ratio a / h was greater than 1.5 (which is necessary for Fund (III) to accurately calculate the stress intensity). At this point, the crack length a was measured and recorded using a moving microscope with a resolution of 5 μm. Next, a drop of toluene was placed in the crack groove and carried along the entire length of the groove by capillary forces, pinning the crack to prevent movement until the fracture toughness was reached. The load was then increased until the specimen broke, and the critical stress intensity K was calculated from the fracture load and specimen dimensions. IC was calculated. P is the measurement method, K IC is equal to.

[0073] The Young's modulus (E) of the glass composition used to form the glass-based article is inversely related to the drop performance of the glass-based article, as shown by equations (I) and (II). In embodiments, the composition used to form the glass-based article has a Young's modulus of 76 to 115 GPa, 77 to 113 GPa, 78 to 112 GPa, 79 to 111 GPa, 80 to 110 GPa, 81 to 109 GPa, 82 to 108 GPa, 83 to 107 GPa, 84 to 106 GPa, 85 to 105 GPa, 86 GPa, 87 to 109 GPa, 88 to 109 GPa, 89 to 109 GPa, 90 to 106 GPa, 91 to 109 GPa, 92 to 109 GPa, 93 to 107 GPa, 94 to 106 GPa, 95 to 105 GPa, 96 to 106 GPa, 97 to 109 GPa, 98 to 105 GPa, 99 to 111 GPa, 100 to 111 GPa, 101 to 109 GPa, 102 to 109 GPa, 103 to 104 GPa, 105 to 106 GPa, 106 to 105 GPa, 107 to 108 GPa, 108 to 109 GPa, 110 to 111 GPa, 112 to 112 GPa, 113 to 113 GPa, 114 to 114 GPa, 115 to 115 GPa, 116 to 116 GPa, 117 to 117 GPa, In some embodiments, the composition used to form the glass-based article exhibits a Young's modulus (E) of from 75 GPa to 120 GPa, such as from 80 GPa to 104 GPa, from 87 GPa to 103 GPa, from 88 GPa to 102 GPa, from 89 GPa to 101 GPa, from 90 GPa to 100 GPa, from 91 GPa to 99 GPa, from 92 GPa to 98 GPa, from 93 GPa to 97 GPa, from 94 GPa to 96 GPa, or equal to 95 GPa, and all ranges and sub-ranges therebetween. In embodiments, the composition used to form the glass-based article exhibits a Young's modulus (E) of from 80 GPa to 120 GPa. The Young's modulus values ​​recited in this disclosure refer to values ​​as measured by the general type of resonant ultrasonic spectroscopy technique set forth in ASTM E2001-13, entitled "Standard Guide for Resonant Ultrasound Spectroscopy for Defect Detection in Both Metallic and Non-metallic Parts."

[0074] The hardness (H) of the glass composition used to form the glass-based article is positively correlated with the drop performance of the glass-based article, as shown by equations (I) and (II). In embodiments, the composition used to form the glass-based article exhibits a hardness (H) of 6.0 GPa to 8.0 GPa, including 6.1 GPa to 7.9 GPa, 6.2 GPa to 7.8 GPa, 6.3 GPa to 7.7 GPa, 6.4 GPa to 7.6 GPa, 6.5 GPa to 7.5 GPa, 6.6 GPa to 7.4 GPa, 6.7 GPa to 7.3 GPa, 6.8 GPa to 7.2 GPa, 6.9 GPa to 7.1 GPa, or equal to 7.0 GPa, and all ranges and subranges therebetween. The hardnesses recited in this disclosure refer to values ​​as measured by the Vickers hardness test. The Vickers hardness test involved indentation with the tip of a Vickers indenter with a load of 200 grams for 15 seconds.

[0075] The glass-based article may have any suitable thickness. The thickness (t) of the glass-based article is inversely related to the drop performance of the glass-based article, as shown by formula (I). In embodiments, the glass-based article may have a thickness (t) of from 0.2 mm to 2.0 mm, such as from 0.3 mm to 1.0 mm, from 0.4 mm to 0.9 mm, from 0.5 mm to 0.8 mm, from 0.6 mm to 0.7 mm, and all ranges and sub-ranges therebetween.

[0076] As previously mentioned, glass-based articles can be strengthened, such as by ion exchange, to produce damage-resistant glass for applications such as, but not limited to, displays or electronic device enclosures. Referring to Figure 2, the glass-based article has a first region under compressive stress (e.g., first and second compressive layers 120, 122 in Figure 2) extending from the surface of the glass-based article to a depth of compression (DOC), and a second region under tensile stress or central tension (CT) extending from the DOC to a central or interior region of the glass-based article (e.g., central region 130 in Figure 2). As used herein, DOC refers to the depth within the glass-based article where stress changes from compression to tension. At the DOC, the stress crosses from positive (compressive) to negative (tensile) stress, and therefore exhibits a stress value of zero.

[0077] In accordance with conventions commonly used in the art, compression or compressive stress is expressed as a negative (<0) stress, and tension or tensile stress is expressed as a positive (>0) stress. However, throughout this specification, Cs is expressed as a positive or absolute value—i.e., as set forth herein, Cs = |Cs|. Compressive stress (Cs) has a maximum value at or near the surface of the glass-based article, and Cs varies with distance d from the surface according to a function. Referring again to FIG. 2 , first segment 120 extends from first surface 110 to a depth d1, and second segment 122 extends from second surface 112 to a depth d2. Together, these segments define the compression or Cs of glass-based article 100. Compressive stress (including surface Cs) is measured with a surface stress meter (FSM) using a commercially available instrument, such as the FSM-6000 manufactured by Orihara Seisakusho Co., Ltd. (Japan). Surface stress measurements rely on precise measurement of the stress-optical coefficient (SOC), which is related to the birefringence of the glass. The SOC is then measured according to Procedure C (Glass Disk Method) 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.

[0078] In some embodiments, the CS of the glass-based article is from 300 MPa to 1300 MPa, such as from 325 MPa to 1250 MPa, from 350 MPa to 1200 MPa, from 375 MPa to 1150 MPa, from 400 MPa to 1100 MPa, from 425 MPa to 1050 MPa, from 450 MPa to 1000 MPa, from 475 MPa to 975 MPa, from 500 MPa to 950 MPa, from 525 MPa to 925 MPa, from 550 MPa to 900 MPa, from 575 MPa to 875 MPa, from 600 MPa to 850 MPa, from 625 MPa to 825 MPa, from 650 MPa to 800 MPa, from 675 MPa to 775 MPa, or from 700 MPa to 750 MPa, and all ranges and sub-ranges therebetween. In some embodiments, the CS of the glass-based article is 100 MPa or greater.

[0079] In one or more embodiments, Na + and K. + ions are exchanged into the glass-based article, and this Na + The ion is K + ions diffuse to a greater depth in glass-based articles than K +The ion penetration depth ("potassium DOL") is distinct from the DOC because it represents the penetration depth of potassium as a result of the ion exchange process. The potassium DOL is typically smaller than the DOC for the articles described herein. The potassium DOL is measured using a surface stress meter, such as the commercially available FSM-6000 surface stress meter manufactured by Orihara Seisakusho Co., Ltd. (Japan), which relies on precise measurement of the stress optical coefficient (SOC), as described above with respect to the CS measurement. The potassium DOL of each of the first and second compressive layers 120, 122 is 5 μm to 30 μm, such as 6 μm to 25 μm, 7 μm to 20 μm, 8 μm to 15 μm, or 9 μm to 10 μm, and all ranges and subranges therebetween. In other embodiments, the potassium DOL of each of the first and second packed layers 120, 122 is from 6 μm to 30 μm, such as from 10 μm to 30 μm, from 15 μm to 30 μm, from 20 μm to 30 μm, or from 25 μm to 30 μm, and all ranges and sub-ranges therebetween. In still other embodiments, the potassium DOL of each of the first and second packed layers 120, 122 is from 5 μm to 25 μm, such as from 5 μm to 20 μm, from 5 μm to 15 μm, or from 5 μm to 10 μm, and all ranges and sub-ranges therebetween.

[0080] The compressive stresses on both major surfaces (110, 112 in FIG. 1) are balanced by a storage tension in the central region (130) of the glass. The maximum central tension (CT) and DOC values ​​are measured using a scattered light polariscope (SCALP) known in the art. The refractive near-field (RNF) method or SCALP may be used to measure the stress profile. When the RNF method is used to measure the stress profile, the maximum CT value given by SCALP is used for the RNF method. Specifically, the stress profile measured by RNF is force balanced and calibrated to the maximum CT value given by the SCALP measurement. This RNF method is described in U.S. Pat. No. 8,854,623, entitled "Systems and methods for measuring a profile characteristic of a glass sample," which is incorporated herein by reference in its entirety. The RNF method includes the steps of placing a glass article adjacent to a reference block, generating a polarization-switched light beam that is switched between orthogonal polarizations at a rate between 1 Hz and 50 Hz, measuring the power output of the polarization-switched light beam, and generating a polarization-switched reference signal, wherein the measured power outputs of each of the orthogonal polarizations are within 50% of each other. The method further includes transmitting the polarization-switched light beam through the glass sample and the reference block for different depths in the glass sample, and then relaying the transmitted polarization-switched light beam to a signal photodetector using relay optics, which generates a polarization-switched detector signal. The method also includes dividing the detector signal by the reference signal to form a normalized detector signal, and determining a profile characteristic of the glass sample from the normalized detector signal.

[0081] In embodiments, the glass-based article may have a maximum CT of 95 MPa or greater, such as 100 MPa or greater, 105 MPa or greater, 110 MPa or greater, 110 MPa or greater, 120 MPa or greater, 130 MPa or greater, 140 MPa or greater, or 150 MPa or greater, or greater. In some embodiments, the glass-based article may have a maximum CT of 200 MPa or less, such as 190 MPa or less, 180 MPa or less, 170 MPa or less, 160 MPa or less, 150 MPa or less, 140 MPa or less, 130 MPa or less, 120 MPa or less, 110 MPa or less, or 100 MPa or less. It should be understood that any of the above ranges may be combined with any other range in embodiments. However, in other embodiments, the glass-based article may have a maximum CT of from 95 MPa to 200 MPa, such as from 100 MPa to 190 MPa, from 110 MPa to 180 MPa, from 120 MPa to 170 MPa, from 130 MPa to 160 MPa, or from 140 MPa to 150 MPa, and all ranges and sub-ranges therebetween.

[0082] The maximum central tension (CT) may also be described in terms of the thickness of the glass-based article. In embodiments, the glass-based article may have a maximum CT of 120 / √(t) MPa or less, where t is in mm, such as 110 / √(t) MPa or less, 110 / √(t) MPa or less, 100 / √(t) MPa or less, 90 / √(t) MPa or less, 80 / √(t) MPa or less, 70 / √(t) MPa or less, 60 / √(t) MPa or less, 50 / √(t) MPa or less, 40 / √(t) MPa or less, 30 / √(t) MPa or less, 20 / √(t) MPa or less, 10 / √(t) MPa or less, or even less. In embodiments, the glass-based article may have a maximum CT of 120 / √(t)MPa or less, where t is in mm, such as 110 / √(t)MPa or less, 110 / √(t)MPa or less, 100 / √(t)MPa or less, 90 / √(t)MPa or less, 80 / √(t)MPa or less, 70 / √(t)MPa or less, 60 / √(t)MPa or less, 50 / √(t)MPa or less, 40 / √(t)MPa or less, 30 / √(t)MPa or less, 20 / √(t)MPa or less, 10 / √(t)MPa or less, or even less. In embodiments, the glass-based article may have a maximum CT of 10 / √(t)MPa or greater, where t is in mm, such as 20 / √(t)MPa or greater, 30 / √(t)MPa or greater, 40 / √(t)MPa or greater, 50 / √(t)MPa or greater, 60 / √(t)MPa or greater, 70 / √(t)MPa or greater, 80 / √(t)MPa or greater, 90 / √(t)MPa or greater, 100 / √(t)MPa or greater, 110 / √(t)MPa or greater, or greater. In embodiments, the glass-based article may have a maximum CT of from 10 / √(t)MPa to 120 / √(t)MPa, inclusive, where t is expressed in mm, such as from 20 / √(t)MPa to 110 / √(t)MPa, from 30 / √(t)MPa to 100 / √(t)MPa, from 40 / √(t)MPa to 90 / √(t)MPa, from 50 / √(t)MPa to 80 / √(t)MPa, from 60 / √(t)MPa to 70 / √(t)MPa, inclusive, and all ranges and sub-ranges therebetween.

[0083] The glass-based article may have any suitable depth of compression (DOC), in embodiments, from 75 μm to 300 μm, such as from 85 μm to 290 μm, from 95 μm to 280 μm, from 100 μm to 270 μm, from 110 μm to 260 μm, from 120 μm to 250 μm, from 130 μm to 240 μm, from 140 μm to 230 μm, from 150 μm to 220 μm, from 160 μm to 210 μm, from 170 μm to 200 μm, from 180 μm to 190 μm, and all ranges and sub-ranges therebetween.

[0084] The DOC, in some embodiments, is given herein as a fraction of the thickness (t) of the glass-based article. In embodiments, the glass-based article may have a depth of compression (DOC) of from 0.18t to 0.38t, or from 0.19t to 0.36t, from 0.20t to 0.34t, from 0.18t to 0.32t, from 0.19t to 0.30t, from 0.20t to 0.29t, from 0.21t to 0.28t, from 0.22t to 0.27t, from 0.23t to 0.26t, or from 0.24t to 0.25t, such as from 0.15t to 0.40t, and all ranges and sub-ranges therebetween.

[0085] The glass-based articles described herein may exhibit any suitable amount of stored tensile energy (STE). In embodiments, the glass-based articles may have a STE of 5 Pa·m or greater, such as 6 Pa·m or greater, 7 Pa·m or greater, 8 Pa·m or greater, 9 Pa·m or greater, 10 Pa·m or greater, 11 Pa·m or greater, 12 Pa·m or greater, 13 Pa·m or greater, 14 Pa·m or greater, 15 Pa·m or greater, 16 Pa·m or greater, 17 Pa·m or greater, 18 Pa·m or greater, 19 Pa·m or greater, 20 Pa·m or greater, 21 Pa·m or greater, 22 Pa·m or greater, 23 Pa·m or greater, 24 Pa·m or greater, 25 Pa·m or greater, 26 Pa·m or greater, 27 Pa·m or greater, 28 Pa·m or greater, 29 Pa·m or greater, or greater. In embodiments, the glass-based article may have a STE of 30 Pa·m or less, such as 29 Pa·m or less, 28 Pa·m or less, 27 Pa·m or less, 26 Pa·m or less, 25 Pa·m or less, 24 Pa·m or less, 23 Pa·m or less, 22 Pa·m or less, 21 Pa·m or less, 20 Pa·m or less, 19 Pa·m or less, 18 Pa·m or less, 17 Pa·m or less, 16 Pa·m or less, 15 Pa·m or less, 14 Pa·m or less, 13 Pa·m or less, 12 Pa·m or less, 11 Pa·m or less, 10 Pa·m or less, 9 Pa·m or less, 8 Pa·m or less, 7 Pa·m or less, 6 Pa·m or less, 5 Pa·m or less, or even less. In embodiments, the glass-based article may have an STE of from 5 Pa·m to 30 Pa·m, such as from 6 Pa·m to 29 Pa·m, from 7 Pa·m to 28 Pa·m, from 8 Pa·m to 27 Pa·m, from 8 Pa·m to 26 Pa·m, from 9 Pa·m to 25 Pa·m, from 10 Pa·m to 24 Pa·m, from 11 Pa·m to 23 Pa·m, from 12 Pa·m to 23 Pa·m, from 13 Pa·m to 22 Pa·m, from 14 Pa·m to 21 Pa·m, from 15 Pa·m to 20 Pa·m, from 16 Pa·m to 19 Pa·m, from 17 Pa·m to 18 Pa·m, and all ranges and sub-ranges therebetween.

[0086] As used herein, the stored tensile energy (STE) of a glass-based article is calculated according to the following formula (IV):

[0087]

number

[0088] where v is Poisson's ratio, E is Young's modulus, σ(z) is stress as a function of position (z) through the thickness, and the integral is over the tensile region only. Equation (IV) is described as Equation Number 4 in "Frangibility of Tempered Soda-Lime Glass Sheet" by Suresh T. Gulati at GLASS PROCESSING DAYS, The Fifth International Conference on Architectural and Automotive Glass, September 13-15, 1997. The Poisson's ratio values ​​listed in this disclosure refer to values ​​measured by the general type of resonant ultrasonic spectroscopy technique described in ASTM E2001-13, entitled "Standard Guide for Resonant Ultrasound Spectroscopy for Defect Detection in Both Metallic and Non-metallic Parts."

[0089] The glass-based article may be formed by exposing a glass-based substrate to an ion exchange solution to form a glass-based article having a compressive stress layer extending from the surface of the glass-based article to a compression depth. The ion exchange process may be carried out under conditions sufficient to produce a glass-based article satisfying any of formulas (I), (IA), and (II). In embodiments, the ion exchange solution may be molten nitrate. In some embodiments, the ion exchange solution may be molten KNO, molten NaNO, or a combination thereof. In certain embodiments, the ion exchange solution may comprise less than about 95% molten KNO, such as less than about 90% molten KNO, less than about 80% molten KNO, less than about 70% molten KNO, less than about 60% molten KNO, or less than about 50% molten KNO. In certain embodiments, the ion exchange solution may include at least about 5% molten NaNO, such as at least about 10% molten NaNO, at least about 20% molten NaNO, at least about 30% molten NaNO, or at least about 40% molten NaNO. In other embodiments, the ion exchange solution may include about 95% molten KNO and about 5% molten NaNO, about 94% molten KNO and about 6% molten NaNO, about 93% molten KNO and about 7% molten NaNO, about 80% molten KNO and about 20% molten NaNO, about 75% molten KNO and about 25% molten NaNO, about 70% molten KNO and about 30% molten NaNO, about 65% molten KNO and about 35% molten NaNO, or about 60% molten KNO and about 40% molten NaNO, and all ranges and subranges therebetween. In embodiments, other sodium and potassium salts may be used in the ion exchange solution, such as, for example, sodium or potassium nitrites, phosphates, or sulfates. In some embodiments, the ion exchange solution may include a lithium salt, such as LiNO.

[0090] The glass-based substrate may be exposed to the ion exchange solution by immersing the glass-based substrate in a bath of the ion exchange solution, by spraying the glass-based substrate with the ion exchange solution, or by otherwise physically applying the ion exchange solution to the glass-based substrate. During exposure of the glass-based substrate, the ion exchange solution may be at a temperature of from 350° C. to 490° C., from 360° C. to 480° C., from 370° C. to 470° C., from 380° C. to 460° C., from 390° C. to 450° C., from 400° C. to 440° C., from 410° C. to 430° C., equal to 420° C., and all ranges and subranges therebetween, according to embodiments. In embodiments, the glass composition may be exposed to the ion exchange solution for a period of time from 2 to 48 hours, such as from 4 to 44 hours, from 8 to 40 hours, from 12 to 36 hours, from 16 to 32 hours, from 20 to 28 hours, equal to 24 hours, etc., and all ranges and subranges therebetween.

[0091] The ion exchange process provides an improved compressive stress profile, as disclosed, for example, in U.S. Patent Application Publication No. 2016 / 0102011, which is incorporated herein by reference in its entirety. The composition of the ion exchange bath, the temperature and time of ion exchange, etc. The ion exchange process may be carried out in an ion exchange solution under processing conditions. In some embodiments, the ion exchange process may be selected to produce a parabolic stress profile in the glass article, such as the stress profile described in U.S. Patent Application Publication No. 2016 / 0102014, which is incorporated herein by reference in its entirety.

[0092] It should be understood that after the ion exchange process has been performed, the composition at the surface of the glass-based article will be different from the composition of the glass-based substrate before the ion exchange process. This is because, for example, + or K + exchanged by larger alkali metal ions such as Li + or Na +However, the glass composition and phase assemblage at or near the center of the depth of the glass-based article will still have the composition of the glass-based substrate, in embodiments.

[0093] The glass-based substrate that is ion-exchanged to form the glass-based article may have any suitable composition, such as an alkali aluminosilicate composition. In embodiments, the glass-based substrate comprises SiO, AlO, BO, and at least one alkali metal oxide. The at least one alkali metal oxide facilitates ion exchange of the glass-based substrate. For example, the glass-based substrate may comprise Na, SiO, AlO, BO, and at least one alkali metal oxide to form the glass-based article. + and K. + It may contain Li2O and / or Na2O to facilitate the exchange of ions into the glass-based substrate. As noted above, the composition of the glass-based substrate may be equivalent to the composition and phase assemblage at the center of the glass-based article.

[0094] In the glass-based substrate embodiments described herein, concentrations of constituent elements (e.g., SiO, AlO, LiO, etc.) are given in mole percent (mol%) on an oxide basis unless otherwise specified. Components of glass-based substrates according to embodiments are described individually below. It should be understood that any of the various recited ranges for a component may be individually combined with any of the various recited ranges for any other component.

[0095] In embodiments of the glass-based substrates disclosed herein, SiO2 is the largest component, and therefore, SiO2 is the major component of the glass network formed from the glass composition. Pure SiO2 has a relatively low CTE and is alkali-free. However, pure SiO2 has a high melting point. Therefore, if the concentration of SiO2 in the glass-based substrate is too high, the formability of the glass composition may be impaired, as higher concentrations of SiO2 increase the difficulty of melting the glass (which, in turn, adversely affects the formability of the glass). In embodiments, the glass-based substrate generally comprises SiO2 in an amount of from 50.0 mol% to 69.0 mol%, inclusive, and all ranges and subranges therebetween. In embodiments, the glass-based substrate comprises SiO in an amount from 51.0 mol% to 68.0 mol%, such as from 52.0 mol% to 67.0 mol%, from 53.0 mol% to 66.0 mol%, from 54.0 mol% to 65.0 mol%, from 55.0 mol% to 64.0 mol%, from 56.0 mol% to 63.0 mol%, from 57.0 mol% to 62.0 mol%, from 58.0 mol% to 61.0 mol%, or from 60.0 mol% to 61.0 mol%, and all ranges and sub-ranges therebetween.

[0096] The glass-based substrate of an embodiment may further include Al2O3. Like SiO2, Al2O3 may act as a glass network former. Due to its tetrahedral coordination in a glass melt formed from the glass composition, Al2O3 may increase the viscosity of the glass composition, and if the amount of Al2O3 is too high, it may reduce the formability of the glass composition. However, when the concentration of Al2O3 is balanced relative to the concentrations of SiO2 and alkali oxides in the glass-based substrate, Al2O3 can lower the liquidus temperature of the glass melt, thereby increasing the liquidus viscosity and improving the compatibility of the glass composition with certain forming processes, such as fusion forming processes. In an embodiment, the glass-based substrate generally includes Al2O3 in a concentration of from 12.5 mol% to 25.0 mol% and all ranges and subranges therebetween. In embodiments, the glass-based substrate comprises Al2O3 in an amount of from 13.0 mol% to 24.5 mol% or less, such as from 13.5 mol% to 24.0 mol%, from 14.0 mol% to 23.5 mol%, from 14.5 mol% to 23.0 mol%, from 15.0 mol% to 22.5 mol%, from 15.5 mol% to 22.0 mol%, from 16.0 mol% to 21.5 mol%, from 16.5 mol% to 21.0 mol%, from 17.0 mol% to 20.5 mol%, from 17.5 mol% to 20.0 mol%, from 18.0 mol% to 19.5 mol%, or from 18.5 mol% to 19.0 mol%, and all ranges and sub-ranges therebetween.

[0097] Like SiO and AlO, BO may be added to glass-based substrates as a network former, thereby reducing the meltability and formability of the glass composition. Therefore, BO should be added in an amount that does not excessively reduce these properties. In embodiments, the glass-based substrate may contain BO in an amount of from 0 mol% to 8.0 mol%, inclusive, and all ranges and subranges therebetween. In embodiments, the glass-based substrate may contain BO in an amount of from 0 mol% to 7.5 mol%, inclusive, such as from 1.0 mol% to 7.0 mol%, from 1.5 mol% to 6.5 mol%, from 2.0 mol% to 6.0 mol%, from 2.5 mol% to 5.5 mol%, from 3.0 mol% to 5.0 mol%, or from 3.5 mol% to 4.5 mol%, inclusive, and all ranges and subranges therebetween.

[0098] The inclusion of Li2O in the glass-based substrate allows for better control of the ion exchange process and further reduces the softening point of the glass, thereby increasing the manufacturability of the glass. In embodiments, the glass-based substrate typically contains 8.0 mol% Li2O. Super from 18.0 mole % In embodiments, the glass-based substrate comprises LiO in an amount of from 8.5 mol% to 17.5 mol%, such as from 9.0 mol% to 17.0 mol%, from 9.5 mol% to 16.5 mol%, from 10.0 mol% to 16.0 mol%, from 10.5 mol% to 15.5 mol%, from 11.0 mol% to 15.0 mol%, from 11.5 mol% to 14.5 mol%, from 12.0 mol% to 14.0 mol%, or from 12.5 mol% to 13.5 mol%, and all ranges and sub-ranges therebetween.

[0099] According to embodiments, the glass-based substrate may also include alkali metal oxides other than LiO, such as NaO. NaO contributes to the ion-exchange functionality of the glass composition and also improves the formability of the glass composition, thereby improving its manufacturability. However, if too much NaO is added to the glass-based substrate, the CTE may be too low and the melting point may be too high. In embodiments, the glass-based substrate generally includes NaO in an amount of from greater than or equal to 0.5 mol % to less than or equal to 8.0 mol %, including all ranges and subranges therebetween. In embodiments, the glass-based substrate comprises NaO in an amount from 1.0 mol % to 7.5 mol %, such as from 1.5 mol % to 7.0 mol %, from 2.0 mol % to 6.5 mol %, from 2.5 mol % to 6.0 mol %, from 3.0 mol % to 5.5 mol %, from 3.5 mol % to 5.0 mol %, or from 4.0 mol % to 4.5 mol %, and all ranges and sub-ranges therebetween.

[0100] Like NaO, KO also promotes ion exchange and increases the DOC of the compressive stress layer. However, adding KO can result in a CTE that is too low and a melting point that is too high. In some embodiments, the glass-based substrate can include KO. In embodiments, the glass composition is substantially free of potassium. As used herein, the term "substantially free" means that the component is not added as a component of the batch materials, although the component may be present in the final glass in very small amounts, such as less than 0.01 mol %, as a contaminant. In other embodiments, KO can be present in the glass-based substrate in an amount less than 1 mol %.

[0101] MgO reduces the viscosity of the glass, thereby improving its formability and manufacturability. The inclusion of MgO in a glass-based substrate can also improve the strain point and Young's modulus of the glass composition and may also improve the ion-exchangeability of the glass. However, adding too much MgO to a glass composition can undesirably increase the density and CTE of the glass composition. In embodiments, the glass-based substrate generally includes MgO in a concentration of greater than 0 mol % to less than or equal to 17.5 mol %, and all ranges and subranges therebetween. In an embodiment, the glass-based substrate has a SiO 2 content of 1.0 mol % to 16.5 mol %, 1.5 mol % to 16.0 mol %, 2.0 mol % to 15.5 mol %, 2.5 mol % to 15.0 mol %, 3.0 mol % to 14.5 mol %, 3.5 mol % to 14.0 mol %, 4.0 mol % to 13.5 mol %, 4.5 mol % to 13.0 mol %, 5.0 mol % to 12.5 mol %. %, 5.5 mol% to 12.0 mol%, 6.0 mol% to 11.5 mol%, 6.5 mol% to 11.0 mol%, 7.0 mol% to 10.5 mol%, 7.5 mol% to 10.0 mol%, 8.0 mol% to 9.5 mol%, or 8.5 mol% to 9.0 mol%, such as 0.5 mol% to 17.0 mol%, and all ranges and sub-ranges therebetween.

[0102] CaO reduces the viscosity of the glass, which can improve formability, strain point, and Young's modulus, and can improve ion-exchangeability. However, adding too much CaO to a glass-based substrate can increase the density and CTE of the glass composition. In embodiments, the glass-based substrate generally contains CaO in a concentration of greater than 0 mol% to less than or equal to 4.0 mol%, and all ranges and subranges therebetween. In embodiments, the glass-based substrate contains CaO in an amount of greater than or equal to 0.5 mol% to less than or equal to 3.5 mol%, such as greater than or equal to 1.0 mol% to less than or equal to 3.0 mol%, or greater than or equal to 1.5 mol% to less than or equal to 2.5 mol%, and all ranges and subranges therebetween.

[0103] La2O3 increases the toughness of the glass and also increases the Young's modulus and hardness of the glass. However, if too much La2O3 is added to a glass composition, the glass becomes more susceptible to devitrification, reducing the manufacturability of the glass. In embodiments, the glass-based substrate generally includes La2O3 in a concentration of from 0 mol% to 2.5 mol% inclusive, and all ranges and subranges therebetween. In embodiments, the glass-based substrate includes La2O3 in an amount of from 0.5 mol% to 2.0 mol% inclusive, such as from 1.0 mol% to 1.5 mol% inclusive, and all ranges and subranges therebetween. In some embodiments, the glass composition is free or substantially free of La2O3.

[0104] Y2O3 also increases the toughness of the glass, increasing the Young's modulus and hardness of the glass. However, if too much Y2O3 is added to the glass composition, the glass becomes more susceptible to devitrification, reducing the manufacturability of the glass. In embodiments, the glass-based substrate contains from 0 mol % to 2.0 % or less, and all ranges and subranges therebetween. In embodiments, the glass-based substrate includes Y2O3 in an amount of greater than or equal to 0.5 mol % to less than or equal to 1.5 mol %. In some embodiments, the glass-based substrate is free or substantially free of Y2O3.

[0105] TiO2 also contributes to increased toughness of the glass while softening the glass. However, if too much TiO2 is added to a glass composition, the glass becomes prone to devitrification and exhibits undesirable coloration. In embodiments, the glass-based substrate comprises TiO2 in a concentration of from greater than or equal to 0 mol% to less than or equal to 2.0 mol%, including all ranges and subranges therebetween. In embodiments, the glass-based substrate comprises TiO2 in an amount of from greater than or equal to 0.5 mol% to less than or equal to 1.5 mol%. In some embodiments, the glass-based substrate is free or substantially free of TiO2.

[0106] ZrO2 contributes to the toughness of the glass. However, adding too much ZrO2 to a glass composition can result in the formation of undesirable zirconia inclusions in the glass, due, at least in part, to the low solubility of ZrO2 in the glass. In embodiments, the glass-based substrate includes ZrO2 in a concentration of from 0 mol% to 2.5 mol% or less, and all ranges and subranges therebetween. In embodiments, the glass-based substrate includes ZrO2 in an amount of from 0.5 mol% to 2.0 mol%, and all ranges and subranges therebetween, such as from 1.0 mol% to 1.5 mol% or less. In some embodiments, the glass-based substrate is free or substantially free of ZrO2.

[0107] SrO lowers the liquidus temperature of the glass compositions disclosed herein. In embodiments, the glass-based substrate may include SrO in an amount from 0 mol % to 1.0 mol %, such as from 0.2 mol % to 0.8 mol %, or from 0.4 mol % to 0.6 mol %, and all ranges and subranges therebetween. In some embodiments, the glass-based substrate may be substantially free or free of SrO.

[0108] In embodiments, the glass-based substrate may optionally include one or more fining agents. In some embodiments, the fining agent may include, for example, SnO. In such embodiments, SnO may be present in the glass-based substrate in an amount of 0.2 mol% or less, such as from 0 mol% to 0.1 mol%, and all ranges and subranges therebetween. In other embodiments, SnO may be present in the glass-based substrate in an amount of 0.2 mol% or less, such as from 0 mol% to 0.2 mol%, or from 0.1 mol% to 0.2 mol%, and all ranges and subranges therebetween. In some embodiments, the glass-based substrate may be substantially free or free of SnO.

[0109] In embodiments, the glass-based substrate may be substantially free of arsenic and / or antimony, hi other embodiments, the glass-based substrate may be free of arsenic and / or antimony.

[0110] In one or more embodiments, the glass articles described herein may exhibit an amorphous microstructure and may be substantially free of crystals or crystallites, in other words, the glass articles may, in some embodiments, exclude glass-ceramic materials.

[0111] The glass-based substrate may include a glass-ceramic. The glass-ceramic is characterized by a phase assemblage, the phase assemblage including an amorphous phase and at least one crystalline phase. The crystalline phase of the glass-ceramic may include any suitable crystalline structure, such as a lithium silicate, beta-spodumene, or spinel crystalline structure. The glass-based substrate containing the glass-ceramic may be formed by any suitable method, such as by ceramming a precursor glass.

[0112] The glass-based substrate may be formed by any suitable method. In embodiments, the glass-based substrate may be formed by processes including slot forming, float forming, roll forming, and fusion forming. A drawing process for forming the glass-based substrate is preferred because it can form thin glass articles with fewer defects.

[0113] The glass-based substrate may be characterized by the manner in which it is formed. For example, the glass-based substrate may be characterized as float-formable (i.e., formed by a float process), down-drawable, and particularly, fusion-formable or slot-drawable (i.e., formed by a down-draw process such as a fusion draw process or a slot draw process).

[0114] Some embodiments of the glass-based articles described herein may be formed by a down-draw process. The down-draw process produces glass-based substrates of uniform thickness with relatively pristine surfaces. Because the average bending strength of the glass-based substrate and resulting glass-based article is controlled by the amount and size of surface flaws, pristine surfaces with minimal contact have higher initial strength. Additionally, down-drawn glass-based substrates have very flat and smooth surfaces that can be used in end applications without the need for costly grinding and polishing.

[0115] Some embodiments of the glass-based substrate may be described as fusion-formable (i.e., formable using the fusion draw process). The fusion process employs a drawing vessel having a channel for receiving molten glass raw material. The channel has weirs on both sides of the channel that are open at the top and along the length of the channel. When the channel is filled with molten material, the molten glass overflows the weirs. The molten glass flows down the exterior surface of the drawing vessel due to gravity as two flowing glass films. These exterior surfaces of the drawing vessel extend downward and inward to meet at the lower edge of the vessel. The two flowing glass films join at this edge and fuse to form a single flowing glass article. The fusion draw process offers the advantage that, as the two glass films flowing over the channel fuse together, neither of the exterior surfaces of the resulting glass-based substrate comes into contact with any part of the equipment. Therefore, the surface properties of the fusion-drawn glass-based substrate are not affected by such contact.

[0116] Some embodiments of the glass substrates described herein may be formed by a slot draw process, which is distinct from the fusion draw process. In the slot draw process, molten raw glass is fed into a drawing vessel. The bottom of the vessel has an open slot with a nozzle extending the length of the slot. The molten glass flows through the nozzle / slot and is drawn downward into an annealing zone as a continuous glass-based substrate.

[0117] The glass-based articles disclosed herein may be incorporated into another article, such as an article with a display (or display article) (e.g., consumer electronics including cell phones, tablets, computers, navigation systems, etc.), a building article, a transportation article (e.g., automobiles, trains, aircraft, watercraft, etc.), an appliance, or any article requiring some degree of transparency, scratch resistance, abrasion resistance, or a combination thereof. An exemplary article incorporating any of the glass-based articles disclosed herein is shown in FIGS. 3A and 3B. Specifically, FIGS. 3A and 3B show a consumer electronics device 200 comprising: a housing 202 having a front surface 204, a back surface 206, and sides 208; electrical components (not shown) at least partially inside or completely within the housing, including at least a controller, memory, and a display 210 at or adjacent the front surface of the housing; and a cover substrate 212 at or on the front surface of the housing to cover the display. The cover substrate 212 and / or the housing may comprise any of the glass-based articles disclosed herein. [Example]

[0118] The embodiments will be further clarified by the following examples, which should be understood as not limiting the embodiments described above.

[0119] A glass-based article was prepared having the composition in Table I below, where the concentrations of the components are given in mole percent. Example 1 was cerammed to form a glass-ceramic. The glass-based substrate had a thickness of 0.8 mm.

[0120] [Table 1]

[0121] The glass-based substrate was then ion-exchanged to produce a glass-based article. The properties of the glass-based substrate and glass-based article are given in Table 2 below. Young's modulus (E), hardness (H), and fracture toughness (KIC ) was measured on the glass-based substrate before it was ion-exchanged to form the glass-based article. To measure drop performance, the glass-based article was mounted in a puck simulating a smartphone and dropped onto 30-grit abrasive paper. The drop performance is reported in terms of the maximum drop height in cm before the glass-based article broke.

[0122] [Table 2]

[0123] The relationship between drop performance and the value of formula (I) is shown in Figure 4. The relationship between drop performance and the value of formula (II) is shown in Figure 5. As shown in Figures 4 and 5, glass-based articles that satisfy formulas (I) and (II) exhibit improved drop performance. As shown in Figures 4 and 5, Examples 1 to 3, which satisfy formulas (I) and (II), all exhibited better drop performance than Comparative Examples A to D, which did not satisfy formulas (I) and (II).

[0124] All ranges disclosed herein broadly encompass any and all ranges and subranges encompassed by the disclosed ranges, whether or not such ranges are expressly stated before or after the disclosure.

[0125] It will be apparent to those skilled in the art that various modifications and variations can be made in the embodiments described herein without departing from the spirit and scope of the claimed subject matter. Thus, it is intended that the specification cover modifications and variations of the various embodiments described herein, provided such modifications and variations come within the scope of the appended claims and their equivalents.

[0126] Preferred embodiments of the present invention will be described below in detail.

[0127] Embodiment 1 In glass-based articles, a compressive stress layer extending from the surface of the glass-based article to a compression depth; Including, K IC 2 ×DOC / t×√STE≧7.0×10 11 Pa 2.5 m 1.5 and In the formula, K IC is the Pa·m of a glass-based substrate having the same composition and phase set as the composition and phase set at the center of the glass-based article. 0.5 where DOC is the fracture toughness expressed in m / s, DOC is the compression depth expressed in meters, t is the thickness of the glass-based article expressed in meters, and STE is the stored strain energy of the glass-based article expressed in Pa m.

[0128] Embodiment 2 K IC 2 ×DOC / t×√STE≧8.0×10 11 Pa 2.5 m 1.5 2. The glass-based article of embodiment 1, wherein

[0129] Embodiment 3 K IC 2 ×DOC / t×√STE≧9.0×10 11 Pa 2.5 m 1.5 2. The glass-based article of embodiment 1, wherein

[0130] Embodiment 4 K IC 2 ×DOC / t×√STE≧9.5×10 11 Pa 2.5 m 1.5 2. The glass-based article of embodiment 1, wherein

[0131] Embodiment 5 K IC 2 ×DOC / t×√STE≧1.0×10 12 Pa 2.5 m 1.5 2. The glass-based article of embodiment 1, wherein

[0132] Embodiment 6 In glass-based articles, a compressive stress layer extending from the surface of the glass-based article to a compression depth; Including, K IC 2 ×DOC×√STE≧5.6×10 8 Pa 2.5 m 2.5 and In the formula, K IC is the Pa·m of a glass-based substrate having the same composition and phase set as the composition and phase set at the center of the glass-based article. 0.5 where DOC is the fracture toughness expressed in m / s, DOC is the compression depth expressed in meters, t is the thickness of the glass-based article expressed in meters, and STE is the stored strain energy of the glass-based article expressed in Pa m.

[0133] Embodiment 7 K IC 2 ×DOC×√STE≧6.0×10 8 Pa 2.5 m 2.5 7. The glass-based article of embodiment 6, wherein:

[0134] Embodiment 8 K IC 2 ×DOC×√STE≧7.0×10 8 Pa 2.5 m 2.5 7. The glass-based article of embodiment 6, wherein:

[0135] Embodiment 9 K IC 2 ×DOC×√STE≧8.0×10 8 Pa 2.5 m 2.5 7. The glass-based article of embodiment 6, wherein:

[0136] Embodiment 10 In glass-based articles, a compressive stress layer extending from the surface of the entire glass-based article to a compression depth; Including, K IC 2 ×DOC×H / E×√STE≧4.1×10 7 Pa 2.5 m 2.5 and In the formula, K IC is the Pa·m of a glass-based substrate having the same composition and phase set as the composition and phase set at the center of the glass-based article. 0.5 wherein DOC is the compression depth in meters, H is the hardness in Pascals of a glass-based substrate having a composition and phase assemblage equal to the composition and phase assemblage at the center of the glass-based article, E is the Young's modulus in Pascals of a glass-based substrate having a composition and phase assemblage equal to the composition and phase assemblage at the center of the glass-based article, and STE is the stored strain energy of the glass-based article in Pa m.

[0137] Embodiment 11 K IC 2 ×DOC×H / E×√STE≧4.5×10 7 Pa 2.5 m 2.5 11. The glass-based article of embodiment 10, wherein:

[0138] Embodiment 12 K IC 2 ×DOC×H / E×√STE≧5.0×10 7 Pa 2.5 m 2.5 11. The glass-based article of embodiment 10, wherein:

[0139] Embodiment 13 K IC 2 ×DOC×H / E×√STE≧5.5×10 7 Pa 2.5 m2.5 11. The glass-based article of embodiment 10, wherein:

[0140] Embodiment 14 14. The glass-based article of any of the preceding claims, wherein DOC > 75 μm.

[0141] Embodiment 15 15. The glass-based article of any of the preceding claims, wherein DOC≦300 μm.

[0142] Embodiment 16 16. The glass-based article of any of the preceding claims, wherein DOC≦0.4t.

[0143] Embodiment 17 17. The glass-based article of any of the preceding claims, wherein DOC > 0.1t.

[0144] Embodiment 18 18. The glass-based article of any of the preceding claims, having a maximum central tension, CT, of 95 MPa or greater.

[0145] Embodiment 19 19. The glass-based article of any of the preceding claims, having a maximum central tension, CT, less than or equal to 120 / √t MPa, where t is expressed in mm.

[0146] Embodiment 20 20. The glass-based article of any of the preceding claims, wherein the glass-based article has a thickness, t, of 1.0 mm or less.

[0147] Embodiment 21 21. The glass-based article of any of the preceding claims, wherein the glass-based article has a thickness t of 0.3 mm or greater.

[0148] Embodiment 22 22. The glass-based article of any of the preceding claims, wherein the STE is greater than or equal to 20 Pa·m.

[0149] Embodiment 23 22. The glass-based article of any of the preceding claims, wherein 5 Pa·m≦STE≦10 Pa·m.

[0150] Embodiment 24 24. The glass-based article of any of the preceding claims, wherein the compressive stress layer has a compressive stress CS of 100 MPa or greater.

[0151] Embodiment 25 25. The glass-based article of any one of claims 1 to 24, wherein the compressive stress layer has a compressive stress CS of 400 MPa or greater.

[0152] Embodiment 26 26. The glass-based article of any of the preceding claims, wherein the compressive stress layer has a compressive stress CS of 1300 MPa or less.

[0153] Embodiment 27 27. The glass-based article of any one of claims 1 to 26, wherein the glass-based article is made from a glass-ceramic.

[0154] Embodiment 28 28. The glass-based article of any of the preceding claims, wherein the glass-based article comprises SiO, AlO, BO, and at least one alkali metal oxide.

[0155] Embodiment 29 a glass-based substrate having a composition and phase set equal to the composition and phase set at the center of the glass-based article, and a K IC 29. The glass-based article of any of the preceding claims, having

[0156] Embodiment 30 a glass-based substrate having a composition and phase assemblage equal to the composition and phase assemblage at the center of the glass-based article, the glass-based substrate having a K IC 30. The glass-based article of any of the preceding claims, having

[0157] Embodiment 31 31. The glass-based article of any one of claims 1 to 30, wherein a glass-based substrate having a composition and phase assemblage equal to the composition and phase assemblage at the center of the glass-based article has a hardness H of 6.0 GPa or greater.

[0158] Embodiment 32 32. The glass-based article of any of the preceding claims, wherein a glass-based substrate having a composition and phase assemblage equal to the composition and phase assemblage at the center of the glass-based article has a hardness H of 8.0 GPa or less.

[0159] Embodiment 33 33. The glass-based article of any of the preceding claims, wherein a glass-based substrate having a composition and phase assemblage equal to that at the center of the glass-based article has a Young's modulus, E, of 80 GPa or greater.

[0160] Embodiment 34 34. The glass-based article of any of the preceding claims, wherein a glass-based substrate having a composition and phase assemblage equal to that at the center of the glass-based article has a Young's modulus, E, of 120 GPa or less.

[0161] Embodiment 35 In the method, ion-exchanging a glass-based substrate to form a glass-based article having a compressive stress layer extending from the surface of the glass-based article to a compression depth; and K IC 2 ×DOC / t×√STE≧7.0×10 11 Pa 2.5 m 1.5 and In the formula, K IC is the Pa·m of the glass substrate 0.5 where DOC is the fracture toughness expressed in m / s, DOC is the compression depth expressed in meters, t is the thickness of the glass-based article expressed in meters, and STE is the stored strain energy of the glass-based article expressed in Pa m.

[0162] Embodiment 36 In the method, ion-exchanging a glass-based substrate to form a glass-based article having a compressive stress layer extending from the surface of the glass-based article to a compression depth; and K IC 2 ×DOC×H / E×√STE≧4.1×10 7 Pa 2.5 m 2.5 and In the formula, K IC is the Pa·m of the glass substrate 0.5 where DOC is the compression depth in meters, H is the hardness of the glass-based substrate in Pascals, E is the Young's modulus of the glass-based substrate in Pascals, and STE is the stored strain energy of the glass-based article in Pa m.

[0163] Embodiment 37 37. The method of claim 35 or 36, wherein the glass-based substrate is made from a glass-ceramic.

[0164] Embodiment 38 38. The method of any one of embodiments 35 to 37, wherein the ion-exchanging comprises contacting the glass-based substrate with a molten salt bath.

[0165] Embodiment 39 39. The method of embodiment 38, wherein the molten salt bath comprises at least one of sodium nitrate and potassium nitrate.

[0166] Embodiment 40 40. The method of embodiment 38 or 39, wherein said contacting step lasts for at least 4 hours up to 48 hours.

[0167] Embodiment 41 41. The method of any of embodiments 38 to 40, wherein during the contacting step, the molten salt bath is at a temperature of from 400°C or more to 500°C or less.

[0168] Embodiment 42 42. A glass-based article manufactured by the method of any of claims 35 to 41.

[0169] Embodiment 43 In household electrical appliances, a housing having a front face, a back face, and a side face; an electrical component at least partially disposed within the housing, the electrical component including at least a controller, a memory, and a display, the display being disposed on or adjacent to a front surface of the housing; a cover glass disposed on the display; Equipped with 43. A household appliance wherein at least one of a portion of the housing or a portion of the cover glass is made from the glass-based article of any of claims 1 to 34 or 42. [Explanation of symbols]

[0170] 100 Glass products 110 First Surface 112 Second Surface 120 First Segment 122 Second Segment 130 Central area 200 Household electronics 204 Front 206 Back 208 Side 210 Display 212 Cover board

Claims

1. In glass-based articles, a compressive stress layer extending from the surface of the glass-based article to a compression depth; Including, K ＩＣ ２ ×DOC / t×√STE≧7.0×10 １１ Pa ２．５ m １．５ and In the ceremony, K ＩＣ is the P m of a glass-based substrate having the same composition and phase set as the composition and phase set at the center of the glass-based article. ０．５ where DOC is the depth of compression in meters, t is the thickness of the glass-based article in meters, and STE is the stored strain energy of the glass-based article in Pa m; A glass-based article, wherein 5 Pa·m≦STE≦10 Pa·m.

2. In glass-based articles, a compressive stress layer extending from the surface of the glass-based article to a compression depth; Including, K ＩＣ ２ ×DOC×√STE≧5.6×10 ８ Pa ２．５ m ２．５ and In the ceremony, K ＩＣ is the P m of a glass-based substrate having the same composition and phase set as the composition and phase set at the center of the glass-based article. ０．５ where DOC is the depth of compression in meters, t is the thickness of the glass-based article in meters, and STE is the stored strain energy of the glass-based article in Pa m; A glass-based article, wherein 5 Pa·m≦STE≦10 Pa·m.

3. In glass-based articles, a compressive stress layer extending from the surface of the entire glass-based article to a compression depth; Including, K ＩＣ ２ ×DOC×H / E×√STE≧4.1×10 ７ Pa ２．５ m ２．５ and In the ceremony, K ＩＣ is the P m of a glass-based substrate having the same composition and phase set as the composition and phase set at the center of the glass-based article. ０．５ where DOC is the depth of compression in meters, H is the hardness in Pascals of a glass-based substrate having a composition and phase assemblage equal to that at the center of the glass-based article, E is the Young's modulus in Pascals of a glass-based substrate having a composition and phase assemblage equal to that at the center of the glass-based article, and STE is the stored strain energy of the glass-based article in Pa m; A glass-based article, wherein 5 Pa·m≦STE≦10 Pa·m.

4. 4. The glass-based article according to claim 1, wherein 75 μm≦DOC≦300 μm.

5. The glass-based article according to any one of claims 1 to 4, wherein 0.1t≦DOC≦0.4t.

6. 6. The glass-based article of any one of claims 1 to 5, having a maximum central tension CT of 95 MPa or greater.

7. 7. The glass-based article of any one of claims 1 to 6, having a maximum central tension CT of less than or equal to 120 / √t MPa, where t is expressed in mm.

8. 8. The glass-based article of any one of claims 1 to 7, wherein the glass-based article has a thickness t of 1.0 mm or less.

9. The glass-based article according to any one of claims 1 to 8, wherein the compressive stress layer has a compressive stress CS of 100 MPa or more and 1300 MPa or less.

10. a glass-based substrate having a composition and phase assemblage identical to the composition and phase assemblage at the center of the glass-based article; K between 0.75 MPa√m and 1.5 MPa√m ＩＣ , A hardness H of 6.0 GPa or more and 8.0 GPa or less, and Young's modulus E of 80 GPa or more and 120 GPa or less, The glass-based article of any one of claims 1 to 9, comprising at least one of:

11. In the method, ion-exchanging a glass-based substrate to form a glass-based article having a compressive stress layer extending from a surface of the glass-based article to a compression depth DOC and a stored strain energy STE in a central region; and K ＩＣ ２ ×DOC / t×√STE≧7.0×10 １１ Pa ２．５ m １．５ and In the ceremony, K ＩＣ is the P·m of the glass substrate ０．５ where DOC is the compression depth of the glass-based article in meters, t is the thickness of the glass-based article in meters, and STE is the stored strain energy of the glass-based article in Pa m; the ion exchange comprises contacting the glass-based substrate with a molten salt bath containing sodium nitrate and potassium nitrate at a temperature of 400°C or more and 500°C or less, the contacting lasts for 4 hours or more and 48 hours or less, the ion exchange forms an STE with the DOC of the glass-based article, the glass-based substrate exhibits an amorphous microstructure, and based on a total of 100 mol% of the glass-based substrate, 52.0 mol% or more to 69.0 mol% or less of SiO ２ and, 13.0 mol% or more to 24.5 mol% or less of Al ２ O ３ and, 0 mol % or more to 8.0 mol % or less B ２ O ３ and, More than 8.0 mol% to 18.0 mol% Li ２ O and 0 mol% or more and 17.0 mol% or less of MgO; 0 mol% or more and 4.0 mol% or less of CaO; 0 mol% or more to 2.5 mol% or less of La ２ O ３ and, 0 mol % or more to 2.0 mol % or less of Y ２ O ３ and, 0 mol % or more to 2.0 mol % or less of TiO ２ and, and 0 mol % to 2.5 mol % ZrO ２ and 5 Pa·m≦STE≦10 Pa·m.

12. In the method, ion-exchanging a glass-based substrate to form a glass-based article having a compressive stress layer extending from a surface of the glass-based article to a compression depth DOC and a stored strain energy STE in a central region; and K ＩＣ ２ ×DOC×H / E×√STE≧4.1×10 ７ Pa ２．５ m ２．５ and In the ceremony, K ＩＣ is the P·m of the glass substrate ０．５ where DOC is the depth of compression of the glass-based article in meters, H is the hardness of the glass-based substrate in Pascals, E is the Young's modulus of the glass-based substrate in Pascals, and STE is the stored strain energy of the glass-based article in Pa m; the ion exchange comprises contacting the glass-based substrate with a molten salt bath containing sodium nitrate and potassium nitrate at a temperature of 400°C or more and 500°C or less, the contacting lasts for 4 hours or more and 48 hours or less, the ion exchange forms an STE with a DOC of the glass-based article, the glass-based substrate exhibits an amorphous microstructure, and based on a total of 100 mol% of the glass-based substrate, 52.0 mol% or more to 69.0 mol% or less of SiO ２ and, 13.0 mol% or more to 24.5 mol% or less of Al ２ O ３ and, 0 mol % or more to 8.0 mol % or less B ２ O ３ and, More than 8.0 mol% to 18.0 mol% Li ２ O and 0 mol% or more and 17.0 mol% or less of MgO; 0 mol% or more and 4.0 mol% or less of CaO; 0 mol% or more to 2.5 mol% or less of La ２ O ３ and, 0 mol % or more to 2.0 mol % or less of Y ２ O ３ and, 0 mol % or more to 2.0 mol % or less of TiO ２ and, and 0 mol % to 2.5 mol % ZrO ２ and 5 Pa·m≦STE≦10 Pa·m.

13. In household electrical appliances, a housing having a front face, a back face, and a side face; an electrical component at least partially disposed within the housing, the electrical component including at least a controller, a memory, and a display, the display being disposed on or adjacent to a front surface of the housing; a cover glass disposed on the display; Equipped with A household electrical appliance, wherein at least one of a part of the housing or a part of the cover glass is made from the glass-based article according to any one of claims 1 to 10.

Images