Glass with high elastic modulus

Abstract

A glass includes in terms of mole percent (mol%) of constituents on an oxide basis, at least 10 mol% and no more than 32 mol% silica, at least 20 mol% and no more than 34 mol% alumina, and quicklime and magnesia such that a sum thereof is at least 41 mol% and no more than 60 mol%. A ratio of the magnesia in mol% to the quicklime in mol% is at least 0.10. The glass has an elastic modulus greater than 110 GPa.

Description

GLASS WITH HIGH ELASTIC MODULUSCross-reference to Related Applications

[0001] This application claims the benefit of priority of U.S. Application Serial No. 63 / 575,885, filed on April 08, 2024, the content of which is relied upon and incorporated herein by reference in its entirety.BACKGROUND

[0002] Aspects of the present disclosure relate to glass, as may be used as housings or covers for electronic devices or used otherwise.

[0003] Glass, such as sheets of glass, may provide a protective covering for displays of electronic devices, such as cellular phones and laptop computers. The glass may be formed as sheets by a fusion forming process or by so-called float method. The glass may then be cut to shape and integrated in electronic componentry. Further such glass may be naturally strong and may be further strengthened, such as by ion-exchange chemical tempering for example. However, constituents to make such glass may be quite rare, possibly requiring resource-intensive mining to procure. Further, such mining may be harmful to the environment.

[0004] A need exists for glasses that may serve as protective covers or in applications, but made with common constituents, readily available and / or which may be gathered in a fairly sustainable or eco-friendly manner.SUMMARY

[0005] Glass of the present disclosure includes fairly common constituents, such as quicklime (CaO), alumina (AI2O3), and silica (Si2O). However the constituents are arranged in a manner such that one may expect the combination to produce polycrystalline ceramic, as opposed to single-phase, amorphous glass. More specifically the presently disclosed glass includes a particularly large portion of alkaline earth oxides, and may also include an unusually large amount of alumina. Silica may be a lesser ingredient, comprising a lesser mol% of the glass than the sum of alkaline earth oxides, lesser mol% than quicklime, and / or lesser mol% than alumina.

[0006] According to an aspect, the glass may further include magnesia (MgO) and possibly other constituents such as boria (B2O3), phosphorus pentoxide (P2O5), soda (Na20), and others. With the new combination of such constituents, Applicants discovered glass with a surprisingly high modulus of elasticity, such as exceeding 100 GPa, 110 GPa, 115 GPa, and even exceeding 125 GPa. By contrast, “soda-lime silicate,” glass of roughly 70 wt% silica with 15 wt% soda, 10 wt% quicklime, and 5 wt% small amounts of other compounds such as alumina, potash (K2O), and magnesia (MgO), has an elastic modulus less than 75 GPa, such as about 70 or 72 GPa. Increased stiffness of the presently disclosed glass provides unique advantages in terms of coating performance and scratch resistance for glass made of prevalent ingredients facilitating use of the glass as a protective cover or other applications, such as windows, containers, housings, paneling, and laboratory equipment.

[0007] Accordingly, aspects of the present disclosure relate to glass, methods of making and using the glass, articles comprising glass, and methods of making and using the articles.

[0008] Additional features and advantages are set forth in the detailed description that follows, and in part will be readily apparent to those skilled in the art from the description or recognized by practicing the technology as described in the written description and claims hereof, as well as the appended drawings. It is to be understood that both the foregoing general description and the following detailed description are merely exemplary and are intended to provide an overview or framework to understand the nature and character of the claims.BRIEF DESCRIPTION OF THE FIGURE

[0009] The accompanying figures are included to provide a further understanding and are incorporated in and constitute a part of this specification. The drawing / images of the figures illustrate one or more aspects of the present disclosure, and / or together with the detailed description explain principles and operations of the various aspects. As such, the disclosure will become more fully understood from the following detailed description, taken in conjunction with the accompanying figures, in which:

[0010] FIG. 1 is a front view of a gob-pressed glass article according to an aspect of the present disclosure.

[0011] FIG. 2A is a front view of a crystallized gob.

[0012] FIG. 2B is a front view of another crystallized gob.DETAILED DESCRIPTION

[0013] Before turning to the following detailed description and figures, which illustrate aspects of the present disclosure in detail, it should be understood that the present inventive technology is not limited to the details or methodology set forth in the detailed description or illustrated in the figures. For example, as will be understood by those of ordinary skill in the art, features and attributes associated with an aspect shown in the figures or described in the text relating to an aspect may be applied to another aspect described elsewhere in the text.

[0014] Applicants discovered new glass with useful properties, yet generally made with fairly common constituents. More specifically, the constituents include relatively large amounts of quicklime, alumina, and silica, fairly common materials. According to an aspect, the glass may be single-phase, where the glass is amorphous, as opposed to glass-ceramic, and the glass has generally the same physical and chemical properties throughout, having characteristics of an isotropic, homogenous material. According to an aspect, the glass is at least partially amorphous and comprises an amorphous volume (i.e. contiguous volume without detectable crystals; e.g., box- or cuboid-volume with rectangular sides having dimensions such as 2 mm by 0.5 mm by 1 mm, or spherical volume within a larger boule or other article of glass) greater than or equal to 1 mm3, such as greater than 2 mm3, 5 mm3, 100 mm3, most of the total volume is amorphous, fully amorphous. It should be noted, beyond the above ingredients, the glass may include other alkali metal oxides, such as potash (K2O), and the glass may include alkaline earth oxides beyond quicklime, such as magnesia; and / or may include zirconia (ZrO?) among other constituents.

[0015] Despite wide availability of most or even all constituents of the glass, at least some glasses of the present disclosure have remarkably high moduli of elasticity, such as exceeding 100 GPa, 110 GPa, 115 GPa, and even exceeding 125 GPa. Elastic modulus (also called Young’s modulus) may be measured by Brillouin spectroscopy, resonant ultrasound spectroscopy, or simply tensile test, and corresponds with slope of stress (tensile load over cross-sectional area) versus strain (change in length per unit length) over an elastic region of the stress-strain relationship of the glass, which is approximately until failure for brittlematerials such as glass herein, at standard conditions, such as roughly 20° C, 40% relative humidity, sea level atmospheric pressure, etc.

[0016] Applicants believe new glass made primarily of prevalent ingredients with such high elastic moduli are significant and surprising. Such high-modulus glass advances the art by opening the door for new combinations of materials, such as the glass strengthened by or paired with a coating (e.g., hard coating, anti-reflective coating, anti-glare coating, antimicrobial coating) having a comparable elastic modulus (e.g., within 20 GPa thereof; within 10 GPa thereof; less than that of the glass), and thus overcoming challenges with coatings, such as delamination or interfacial strain caused by elastic modulus mismatch. Further, Applicants believe the glasses disclosed herein have comparable advantages in hardness and scratch-resistance, such as when compared to soda-lime silicate.

[0017] According to an aspect, the glass may be translucent and / or transparent, such as having an average transmittance of at least 10% for light in a wavelength range from 380 nm to 750 nm through a pathlength (e.g., thickness) of a linear dimension (e.g., 0.6 mm, 0.8 mm, 1.0 mm, 1.4 mm, 2 mm), such as at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, and / or even over 90%. Transmittance in the visible spectrum may be measured with a Lambda 950 UV / Vis / NIR Spectrophotometer manufactured by PerkinElmer Inc. (Waltham, Massachusetts USA). The Lambda 950 apparatus may be fitted with a 150 mm integrating sphere. Data may then be collected using an open beam baseline and a Spectralon® reference reflectance disk. For total transmittance, the sample may be fixed at the integrating sphere entry point. The term “average transmittance,” as used herein with respect to the visible spectrum, refers to the average of total transmittance measurements made within a given wavelength range with each whole numbered wavelengths weighted equally. As used herein, the “average transmittance” with respect to the visible spectrum is reported over the wavelength range from 380 nm to 750 nm (inclusive of endpoints). Unless otherwise specified, the average transmittance is indicated for light pathlength (e.g., article thickness) of 0.6 mm through glass of the same composition.

[0018] For “silicate glasses,” silica may typically be the primary or greatest constituent of the glass in mol%, and / or is typically the primary glass former constituent. But for at least some glasses disclosed herein, alumina is the primary glass former; and at least some glasses disclosed herein comprise comparable amounts of silica and alumina, as further explained herein, such as within 20 mol% of one another, within 15 mol%, within 10 mol%. In evensome glass disclosed herein, alumina is the single greatest constituent of the glass in mol%. The alumina may contribute to the particularly high elastic moduli discovered for glasses disclosed herein.

[0019] Notably, concentrations of constituent components are provided herein in representative oxide form (e.g., quicklime, silica, alumina, soda and the like) and are specified in mole percent (mol%) on an oxide basis, unless otherwise specified (e.g., when specified by weight percent). According to an aspect of the present disclosure, the glass comprises at least some silica and / or at least some alumina, such as at least 10 mol% of either or both, such as at least 15 mol% thereof, such as at least 18 mol% thereof, such as at least 20 mol% thereof. According to an aspect of the present disclosure, the glass comprises at least 25 mol% of at least one of silica or alumina. According to an aspect, when alumina is increased, silica is decreased, and vice versa such that the total amount of alumina plus silica is between 41 mol% and 61 mol%, such as between 45 mol% and 55 mol%, which may be viewed as a surprisingly low amount of such network forming constituents by those of skill in the art. Too much silica, such as over 50 mol%, over 45 mol%, or over 42% according to some aspects of the present disclosure, may decrease the elastic modulus or produce a material that is not a single-phase glass when combined with other constituents as disclosed here. Similarly too much alumina, such as over 50 mol%, over 45 mol%, or over 42% according to some aspects of the present disclosure, may produce a material that is not a single-phase glass when combined with other constituents as disclosed here. According to an aspect, alumina of the glass is in a range of 18 mol% to 40 mol% when combined with silica in a similar range of 18 mol% to 42 mol%. This surprisingly low amount of silica and alumina network formers is then offset by a surprisingly large amount of alkaline earth oxides.

[0020] According to an aspect of the present disclosure, the glass comprises a surprisingly large amount of alkaline earth oxides, such as quicklime and magnesia. The amount is such that those of skill in the art may not expect glasses to form. Applicants find that the large amount of alkaline earth oxides in combination with the above network formers (in amounts as described) produces glasses of high elastic modulus, as further disclosed herein. With that said, too much alkaline earth oxides may undermine glass formation. According to an aspect, the glass comprises at least 40 mol% alkaline earth oxides, such as at least 42 mol%, at least 45 mol%, at least 46 mol% and / or no more than 60 mol%.

[0021] According to an aspect, the glass comprises non-zero amounts of both quicklime and magnesia, such as at least 0.08 mol% of each, such as at least 0.1 mol% of each. According to an aspect, the glass comprises such amounts just in terms of a sum of quicklime and magnesia, such as where the sum in mol% of quicklime plus magnesia is at least 40 mol%, at least 41 mol%, at least 42 mol%, at least 45 mol%, at least 46 mol% and / or no more than 60 mol%, such as in a range of 41 mol% to 60 mol% for example. Surprisingly, the sum of alkaline earth oxides (e.g., quicklime plus magnesia) may be greater than silica in mol%, may be greater than alumina in mol%, and / or greater than the sum of network formers, such as the sum of silica and alumina. Such a result, forming a glass of particularly high elastic modulus, is surprising because quicklime and magnesia are typically believed to be modifiers, and such glass may have an excess of modifiers, which would presumably increase non-bridging oxides, presumably lowering elastic modulus. But findings disclosed herein show otherwise. Likewise surprisingly, quicklime may be the greatest oxide constituent of the glass in terms of mol%, as shown in some examples provided herein.

[0022] According to an aspect of the present disclosure, the glass may comprise a nonzero amount of alkali metal oxides, such as soda, lithia, and / or potash, such as at least 0.01 mol% (i.e. as analyzed), such as at least 0.05 mol% of any or all alkali metal oxides, such as at least 0.05 mol% soda. Such soda may be provided in raw materials of the glass, such as accompanying the quicklime and / or magnesia for example. Alkali metal oxides may facilitate strengthening of the glass, such as by ion-exchange, and soda may be a preferred alkali metal oxide because soda is a fairly common material, as opposed to lithia, and sodium is a relatively small atom, useful during ion-exchange chemical tempering where sodium near the surface of an article of such glass may be replaced by larger atoms, such as potassium, another fairly common material, to impart a compressive stress. According to an aspect of the present disclosure, the glass may relatively free of lithia, such as comprising less than 5 mol%, less than 1 mol%, less than 0.1 mol% thereof. Such glass may be of relatively common constituents. However, another contemplated aspect could have high amounts of lithia, such as at least 5 mol%, such as at least 9 mol%, such as at least 10 mol%, at least 11 mol%, and / or no more than 25 mol%. Such glass may benefit from high modulus as well as relatively strong chemical tempering.

[0023] In addition to the above disclosed constituents, glasses disclosed herein may further comprise yttria (Y 2O3), niobium pentoxide (NbzOs), and zirconia (ZrCh) for example.Further, the glass may include some stannic oxide (SnCF) as a fining agent for example, or other fining agents. For example, the glass may include at least 0.01 mol% niobium pentoxide, such at least 0.1 mol%, at least 0.5 mol%, at least 1 mol%, and / or no more than 4 mol%, such as no more than 2 mol%. Likewise, the glass may include at least 0.01 mol% yttria or zirconia, such at least 0. 1 mol%, at least 0.5 mol%, at least 1 mol%, and / or no more than 6 mol%, such as no more than 4 mol%. All three may increase stiffness, but yttria and niobium pentoxide may be fairly rare materials compared to others disclosed herein. Accordingly, some glasses according to aspects of the present disclosure (e.g., reducing need to mine rare metals) may have less than 5 mol% yttria, less than 5 mol% niobium pentoxide, less than 5 mol% lithia, and / or less than 5 mol% oxides of other rare constituents, such as lanthanum and tantalum; such as less than 3 mol%, such as less than 1 mol%, such as less than 0.1 mol%, such as less than 0.05 mol%, such as less than 0.02 mol%, such as less than 0.01 mol% of any one such (e.g., less than 0.01 mol% of Li2O).

[0024] Many of the glasses disclosed herein have particularly high strain points, as shown in the examples, such as over 650° C, such as over 675° C, over 700° C, and even over 800° C in some cases. Accordingly, Applicants believe that the glasses may be chemically tempered in unusually hot baths of molten salt, such as in baths at temperatures exceeding 500° C, such as exceeding 525° C, such as exceeding 550° C, to improve the chemical tempering. Applicants find that to effectively use the salt at such temperatures, a combination of nitrogen- and sulfur-based salts may be used, with increasing weight percentages of sulfur-based salts with higher temperature baths. Further the baths may include potassium- and sodium-containing salts, such as if the glass includes soda or other alkali metal oxides in amounts as disclosed above. As such, according to an aspect, the glasses may be ion-exchanged to have a surface or peak compressive stress (e.g., at least 50 MPa, at least 100 MPa) and central tension (e.g., at least 10 MPa) in a salt bath comprising a molten mixture of sodium nitrate, sodium sulfate, potassium nitrate, and / or potassium sulfate salts at a temperature exceeding 500° C. In the salt bath, wt% of sodium nitrate may be greater than sodium sulfate, wt% of potassium nitrate may be greater than potassium sulfate, and / or wt% of sodium-containing salts may be greater than potassium-containing salts. Hotter salt baths may increase the depth of compression (e.g., at least 5 pm, at least 10 pm, at least 30 pm), where compressive stress transitions to tensile within an article of the glass, may shorten an amount of time for soaking the glass in such baths, and may increase surface or peak compressive stress compared to chemical tempering in salt baths at temperaturesunder 400° C and of all nitrate salts for example. Applicants hereby incorporate by reference herein in its entirety U.S. Application No. 63 / 600,790 filed November 20, 2023.

[0025] Perhaps even more advantageous, some glasses disclosed herein may have sufficient properties (e.g., stiffness, scratch- and drop-performance, hardness, etc.) for applications, such as cover glasses and housings of electronic components, even without ion-exchange. In some aspects, coatings (e.g., hard coatings, anti-scratch coatings) with comparable elastic moduli, as disclosed above, may be sufficient to augment the glass.

[0026] The following Table 1 provides examples of glass made and found to have properties disclosed herein. The examples are presented in terms of mol% as analyzed. Physical properties of the glass are measured by Brillouin scatter and may include some range of error or tolerance for error, such as + / - 10%. Liquidus is measured by gradient boat and may likewise include some range of error or tolerance for error, such as + / - 5%.TABLE 1:TABLE 1 (continued):TABLE 1 (continued):TABLE 1 (continued):

[0027] The following Table 2 provides examples of glass samples made and found to have properties disclosed herein. The examples are provided in terms of mol% as analyzed. The abbreviation RUS is for resonant ultrasound spectroscopy, BBV is for beam bending viscosity, and PPV is for parallel plate viscosity, and measurement methods may include some range of error or tolerance for error, such as + / - 10%; see also ASTM C829-81 and ASTM Cl 35 IM. Liquidus is measured by gradient boat and may likewise include some range of error or tolerance for error, such as + / - 5%; see also ASTM C829-81. Some common properties herein are measured by different techniques (e.g., Brillouin scatter and resonant ultrasound spectroscopy), so unless otherwise specified when claimed, quantities refer to those measurable by the techniques of Table 2, such as with a reasonable degree of error tolerance as disclosed or known in the art.TABLE 2:

[0028] According to an aspect and as shown with the examples, the glass may have a density of at least 2.5 g / cm3, such as at least 2.6 g / cm3, such as at least 2.7 g / cm3, such as at least 2.738 g / cm3, and / or no more than 3.5 g / cm3, such as no more than 3.4 g / cm3, such as no more than 3.367 g / cm3. The density may be for example between 2.6 g / cm3and 3.4 g / cm3.

[0029] According to an aspect and as shown with the examples, the glass may have a refractive index at 589.3 nm using Brillouin scatter of at least 1.5 (unitless), such as at least 1.55, such as at least 1.6, such as at least 1.607, and / or no more than 1.8, such as no more than 1.75, such as no more than 1.741. The refractive index may be for example between 1.55 and 1.75.

[0030] According to an aspect and as shown with the examples, the glass may have a Young’s modulus (aka elastic modulus), as measured by Brillouin scatter or by resonant ultrasound spectroscopy, of at least 95 GPa, such as at least 100 GPa, such as at least 110 GPa, such as at least 115 GPa, such as at least 120 GPa, such as at least 125 GPa, and / or no more than 145 GPa, such as no more than 140 GPa, such as no more than 135 GPa, such as no more than 130 GPa. The Young’s modulus may be for example between 100 GPa and 150 GPa, such as between 110 GPa and 140 GPa, such as between 115 GPa and 135 GPa.

[0031] According to an aspect and as shown with the examples, the glass may have a shear modulus, as measured by Brillouin scatter or by resonant ultrasound spectroscopy, of at least35 GPa, such as at least 38 GPa, such as at least 40 GPa, such as at least 40.54 GPa, and / or no more that 55 GPa, such as no more than 50 GPa, such as no more than 49 GPa. The shear modulus may be for example between 38 GPa and 55 GPa.

[0032] According to an aspect and as shown with the examples, the glass may have a Poisson’s ratio, as measured by Brillouin scatter or by resonant ultrasound spectroscopy, of at least 0.25 (unitless), such as 0.26, such as 0.272 and / or no more than 0.29, such as no more than 0.287. The Poisson’s ratio may be for example between 0.25 and 0.29.

[0033] Viscosity of the glass may be measured according to ASTM C829-81. “Softening point” may refer to the temperature at which viscosity of the glass is 1 x IO7 6poise. The softening point may be measured according to parallel plate viscosity method, which measures viscosity of glass from 107to 109poise as a function of temperature, similar to ASTM Cl 35 IM. “Annealing point” or “anneal point” may refer to the temperature at which viscosity of the glass is 1 x 1013 18poise. “Strain point” may refer to the temperature at which viscosity of the glass is 1 x IO14 68poise. “Liquidus viscosity” may refer to the viscosity of the glass at the onset of devitrification, when crystallization first occurs, or at the liquidus temperature as determined with gradient furnace method according to ASTM C829-81. As such, “liquidus temperature” may refer to the temperature at which the glass composition begins to devitrify as determined with the gradient furnace method according to ASTM C829-81.

[0034] According to an aspect and as shown with the examples, the glass may have a liquidus temperature, as measured by gradient boat, of at least at least 1200° C, such as at least 1300° C, such as at least 1350° C, and / or no more than 1600° C, such as no more than 1500° C. The liquidus temperature may be for example between 1300° C and 1500° C.

[0035] According to an aspect and as shown with the examples, the glass may have a strain point, as measured by beam bending viscosity, of at least at least 600° C, such as at least 620° C, such as at least 650° C, such as at least 700° C, and / or no more than 850° C, such as no more than 800° C. The strain point may be for example between 600° C and 800° C.

[0036] According to an aspect and as shown with the examples, the glass may have an anneal point, as measured by beam bending viscosity, of at least at least 700° C, such as at least 720° C, such as at least 750° C, and / or no more than 900° C, such as no more than 8500° C. The anneal point may be for example between 700° C and 850° C.

[0037] According to an aspect and as shown with the examples, the glass may have a softening point, as measured by parallel plate viscosity, of at least at least 850° C, such as at least 900° C, and / or no more than 1050° C, such as no more than 1000° C. The softening point may be for example between 850° C and 1050° C.

[0038] According to an aspect, the glass may have a liquidus viscosity less than 1000 poise, such as less than 500 poise, such as less than 200 poise, such as no more than 168.5 poise, and / or at least 1 poise, such at least 5 poise, such as at least 7.4 poise. Those of skill in the art may find glass with such low liquidus viscosity challenging to form into articles, such as by fusion or float methods. According to an aspect, methods of making an article with glass disclosed herein comprise gob-pressing the glass, such as dropping a gob of molten glass into a mold and quickly pressing the molten glass to a desired shape, where a gob is a discrete- and relatively-small-volume of molten glass, such as less than 0.5 L for example. “Preshaping” the gob prior to positioning the gob in the mold, such as elongating the gob, may allow for thinner articles with thicker portions further from a center of the mold, for example. U.S. Patent Application No. 63 / 525,060 filed July 5, 2023 is hereby incorporated by reference herein in its entirety. Additionally, pressing the glass more than once may improve dimensional control of the pressing, reducing need for finishing.

[0039] FIG. 1 includes a conceptual representation of a glass article 110 (e.g., parts blank) formed by gob pressing glass as disclosed herein. Such an article may be cut into glass parts, and finished, such as by computer numerical control grinding and polishing, to form an article that may be used in an electronic device, such as a housing or cover as disclosed above, or elsewhere. Similarly, glass disclosed herein may be formed into other articles, such as flat or curved sheets, containers, housings, panels, fibers, substrates (e.g., for memory disk, circuit, packaging), windows, covers, etc.

[0040] Referring to the samples and compositions disclosed above, Applicants discovered that magnesia (MgO), as a greater relative amount of total alkaline earth oxides of a glass (e.g., sum of CaO and MgO, where there are no other alkaline earth oxides) and / or relative to quicklime (CaO), generally increases elastic modulus of glasses as disclosed herein, such as those comprising silica and / or alumina in mol% ranges as disclosed. For example, compare groups of examples 1-7, examples 8-22, and examples 23-31 of Table 1 above.

[0041] The examples have some variations in amounts of silica, alumina, soda, alkaline earth oxides, etc. within disclosed ranges above, but examples 1-7 generally have magnesia as a relatively small percentage of total alkaline earth oxides, typically greater than 4%, but less than 15%, such as generally less than 10%. Similarly, the ratio of MgO:CaO (i.e. mol% MgO divided by mol% CaO) for examples 1-7 is at least 4%, but less than 20%, and mostly less than 15%. The Young’s moduli of these samples is high, greater than 100 GPa, such as greater than 105 GPa, and / or but less than 110 GPa.

[0042] Now compare examples 1-7 with examples 8-22. Examples 8-22 of Table 1 generally have magnesia as a larger percentage of total alkaline earth oxides than examples 1- 7, having typically greater than 10% of the total alkaline earth oxides being magnesia, but less than 40%, such as generally less than 30%. The ratio of MgO:CaO for examples 8-22 mostly at least 10%, and generally less than 50%, mostly less than 40%. Notably, the Young’s moduli of these samples is also greater than 100 GPa, such as mostly greater than 110 GPa, and in some instances greater than 115 GPa, and / or but also less than 120 GPa.

[0043] Lastly now compare examples 1-7 and 8-22 with examples 23-31. Examples 23-31 generally have magnesia as an even larger percentage of total alkaline earth oxides when compared to examples 1-7 and 8-22, typically greater than 20%, but also less than 40%. The ratio of MgO:CaO for examples 23-31 is mostly at least 20%, and generally less than 50%. The Young’s moduli of these samples is also greater than 100 GPa, such as greater than 110 GPa, such as greater than even 120 GPa, and / or but less than 130 GPa.

[0044] Referring now to FIGS. 2A and 2B, clear cups hold crystallized remnants of gobs of glasses similar to glasses disclosed above, but with perhaps excessively high amounts of MgO — 57 mol% in FIG. 2A and 62 mol% in FIG. 2B, each further including 10 mol% CaO (the remainder ~10 mol% silica plus other constituents as disclosed herein, such as boria). Applicants have found that if the ratio of MgO : CaO or the MgO percent of total alkaline earth oxides gets too high for glasses as disclosed herein, such as those having greater than 41 mol% alkaline earth oxides in combination with other ‘common’ constituents, such as with silica, alumina, etc. in ranges as disclosed, risk of devitrification and crystallization increases. As such, crystallized gobs in FIGS. 2A-2B are examples of compositions with perhaps too much MgO for corresponding glasses and forming process. Notably, pressing such glasses in a mold, as disclosed above, may cool the glasses faster, reducing risk of crystallization.

[0045] According to an aspect of the present disclosure, a glass comprises in terms constituents on a representative oxide basis, silica (e.g., nonzero amount, such as 10 mol% but less than 32 mol%), alumina (e.g., nonzero amount, more alumina than silica; greater than 10 mol%, greater than 20 mol%, and / or no more than 40 mol%, such as no more than 32 mol%), optionally alkali metal oxides (e.g., nonzero soda, lithia, potash, such as at least 0.05 mol% of one or more alkali metal oxides, such as soda), and relatively large amounts of alkaline earth oxides, such as quicklime and magnesia, such as at least 40 mol% of such, such as at least 41 mol%, and / or no more than 70 mol%, such as no more than 60 mol%. And, the percentage of magnesia to total alkaline earth oxides (e.g., in wt%) is at least 10%, such as at least 15 %, such as at least 20%, and / or no more than 90%, such as no more than 80%; and the corresponding elastic modulus is at least 110 GPa, such as at least 115 GPa, such as at least 120 GPa, and / or no more than 150 GPa, such as no more than 140 GPa.

[0046] According to an aspect of the present disclosure, a similar glass as just described, with relatively large amounts of alkaline earth oxides, such as quicklime and magnesia, includes a ratio of magnesia to quicklime (MgO:CaO; i.e. mol% MgO divided by mol% CaO) of at least 10%, such as at least 15 %, such as at least 20%, and / or no more than 90%, such as no more than 80%; and the corresponding elastic modulus is at least 110 GPa, such as at least 115 GPa, such as at least 120 GPa, and / or no more than 150 GPa, such as no more than 140 GPa.

[0047] Construction and arrangements of the compositions, assemblies, and structures, as shown in the various aspects, are illustrative only. Although only a few examples of the aspects have been described in detail in this disclosure, modifications are possible (e.g., variations in sizes, dimensions, structures, shapes, and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations) without materially departing from the novel teachings and advantages of the subject matter described herein. For example, while being translucent and / or transparent as disclosed above, the glass and corresponding articles may be colored, and each of U.S. Application No. 63 / 537,466 filed September 8, 2023 and International Application No. PCT / US23 / 82806 filed December 7, 2023 is incorporated by reference herein in its entirety. The order or sequence of any process, logical algorithm, or method steps may be varied or re-sequenced according to alternative embodiments. Other substitutions, modifications, changes and omissions may also be made in the design, operating conditions and arrangement of the various aspects without departing from the scope of the present inventive technology.

Claims

WHAT IS CLAIMED IS:1 . A glass, comprising in terms of mole percent (mol%) of constituents on an oxide basis: at least 10 mol% and no more than 32 mol% silica; at least 20 mol% and no more than 34 mol% alumina; both quicklime and magnesia wherein a sum thereof is greater than 40 mol%; and wherein a ratio of the magnesia in mol% to the quicklime in mol% is at least 0. 10, wherein the glass is amorphous and single-phase; and wherein the glass has an elastic modulus greater than 110 GPa.

2. The glass of claim 1, wherein the quicklime is greater than the silica in terms of mol%.

3. The glass of either claim 1 or claim 2, wherein the quicklime is greater than the magnesia in terms of mol%.

4. The glass of claim 3, wherein the alumina is greater than the silica in terms of mol%.

5. The glass of claim 2, wherein the ratio of magnesia in mol% to quicklime in mol% is at least 0.20 and no more than 0.80.

6. The glass of claim 1, wherein the glass has an average transmittance of at least 10% for light in a wavelength range from 380 nm to 750 nm through a thickness of 0.6 mm.

7. The glass of claim 1, comprising less than 0.01 mol% lithia.

8. The glass of claim 1, comprising less than 1 mol% phosphorus pentoxide.

9. A glass, comprising: constituents comprising quicklime, magnesia, and silica, wherein a sum of the quicklime, the magnesia, and the silica is greater than half of the glass in terms of mole percent (mol%) of constituents on an oxide basis, and wherein the silica is less than 32 mol% of the glass; wherein the glass is a single-phase glass; wherein the glass has an average transmittance of at least 60% for light in a wavelength range from 380 nm to 750 nm through a thickness of 0.6 mm; wherein the magnesia in mol% is at least 10% of all alkaline earth oxides in the glass in mol%; wherein the glass has a modulus of elasticity greater than 110 GPa.

10. The glass of claim 9, wherein the glass comprises at least 41 mol% alkaline earth oxides, including the quicklime and the magnesia as at least part of the alkaline earth oxides.

11. The glass of claim 10, wherein the magnesia in mol% is less than 90% of all alkaline earth oxides in the glass in mol%.

12. The glass of claim 10, wherein the glass comprises a greater mol% of the alkaline earth oxides than the silica.

13. The glass of claim 12, wherein the quicklime is the greatest constituent of the glass in terms of mol%.

14. The glass of claim 9, wherein the glass further comprises alumina, and wherein the alumina is greater than the silica of the glass in terms of mol%.

15. A glass, comprising: constituents comprising quicklime, magnesia, alumina, and silica, wherein a sum of the quicklime and magnesia is greater than a sum of the alumina and silica in terms of mol% of the glass; wherein a ratio of the magnesia in mol% to the quicklime in mol% is at least 0.10, wherein the glass is a single-phase glass; wherein the glass has an average transmittance of at least 60% for light in a wavelength range from 380 nm to 750 nm through a thickness of 0.6 mm; and wherein the glass has a modulus of elasticity greater than 110 GPa.

16. The glass of claim 15, further comprising soda.

17. The glass of claim 16, wherein a sum of soda, quicklime, and silica is greater than half of the glass in terms of mole percent (mol%) of constituents on an oxide basis.

18. The glass of claim 15, wherein silica is not the greatest constituent of the glass in terms of mol%.

19. The glass of claim 15, wherein the quicklime is the greatest constituent of the glass in terms of mol%.

20. The glass of claim 15, wherein the alumina is greater than the silica in terms of mol%.

21. The glass of claim 15, wherein the ratio of magnesia in mol% to quicklime in mol% is at least 0.20 and no more than 0.80.

22. The glass of claim 15, wherein the glass has a modulus of elasticity greater than 120 GPa.

23. A method of making a glass article, comprising: gob-pressing the glass of any of the above claims to at least partially form the article.

24. The method of claim 23, further comprising cooling at least a portion of the glass by at least 500° C in less than 10 seconds.

25. The method of claim 24, wherein the glass after the cooling comprises an amorphous volume greater than 1 mm3.

26. A method of making a glass article, comprising: chemically tempering the glass of any of the above claims in a salt bath at a temperature greater than 600° C.

27. The method of claim 26, wherein the salt bath comprises potassium sulfate.

28. A method of making a glass article, comprising: coating the glass of any of the above claims with a coating having a modulus of elasticity no more than 50 GPa greater than the glass, wherein ultimate strength of the coated glass is greater than ultimate strength of the glass prior to the coating.

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