Novel glass and glass-ceramic compositions

Abstract

Novel glass and glass-ceramic compositions are provided. A composition comprising: 30 to 60 mol% of SiO2; 15 to 35 mol% of Al2O3; 5 to 25 mol% of Y2O3; 0 to 20 mol% of TiO2; and 0 to 25 mol% of R2O, such that R2O is the sum of Na2O, K2O, Li2O, Rb2O, and Cs2O.

Description

[0001] This application claims the priority benefits of U.S. Provisional Application No. 63 / 024,835, filed on May 14, 2020, and Korean Patent Application No. 10-2020-0120241, filed on September 18, 2020, under 35 U.S.C. § 119, the contents of each of which are incorporated herein by reference in their entireties and made the basis hereof. Technical Field

[0002] The present disclosure relates to novel glass and glass-ceramic compositions. Background Art

[0003] High-strength glass and glass-ceramic materials are essential for a wide range of applications including handheld devices, memory disks, and optical fibers. For glass, sufficient mechanical properties can be achieved through compositions containing high proportions of high-field-strength oxides such as MgO, Y2O3, La2O3, etc. Glass-ceramics pose more complex problems. Designing mechanically advantageous glass-ceramics is more difficult to predict because the precursor glass composition does not necessarily indicate the behavior of the composite material (microcrystals and residual glass).

[0004] Accordingly, as described herein, novel glass and glass-ceramic compositions having predictable and excellent mechanical properties are disclosed. Summary of the Invention

[0005] In some embodiments, a composition includes: 30 mol% to 60 mol% of SiO2; 15 mol% to 35 mol% of Al2O3; 5 mol% to 25 mol% of Y2O3; 0 mol% to 20 mol% of TiO2; and 0 mol% to 25 mol% of R2O, where R2O is the sum of Na2O, K2O, Li2O, Rb2O, and Cs2O.

[0006] In one aspect combinable with any other aspect or embodiment, R2O is the sum of Na2O and Li2O. In one aspect combinable with any other aspect or embodiment, R2O consists of Na2O or Li2O. In one aspect combinable with any other aspect or embodiment, R2O contains 0 mol% to 12.5 mol% of Na2O. In one aspect combinable with any other aspect or embodiment, R2O contains 0 mol% to 12.5 mol% of Li2O.

[0007] In one aspect combinable with any other aspect or embodiment, the composition further includes 0 mol% to 2.5 mol% of B2O3. In one aspect combinable with any other aspect or embodiment, the composition further includes 0 mol% to 4 mol% of ZrO2.

[0008] In one aspect, which can be combined with any other aspect or embodiment, the composition comprises: 30 mol% to 40 mol% of SiO2; 25 mol% to 35 mol% of Al2O3; 8 mol% to 14 mol% of Y2O3; and 4 mol% to 18 mol% of TiO2. In one aspect, which can be combined with any other aspect or embodiment, the composition comprises: 0 mol% to 12.5 mol% of Li2O; 0 mol% to 10.5 mol% of Na2O; and 0 mol% to 2.5 mol% of B2O3.

[0009] In one aspect, which can be combined with any other aspect or embodiment, the composition comprises: 30 mol% to 50 mol% of SiO2; 18 mol% to 30 mol% of Al2O3; 10 mol% to 15 mol% of Y2O3; and 4 mol% to 14 mol% of TiO2. In one aspect, which can be combined with any other aspect or embodiment, the composition comprises: 0 mol% to 11.5 mol% of Li2O; 0 mol% to 10.5 mol% of Na2O; and 0 mol% to 4 mol% of ZrO2.

[0010] In one aspect, which can be combined with any other aspect or embodiment, the ratio of R2O to Al2O3 is in the range of 0.1 to 1; or the ratio of Al2O3 to Y2O3 is in the range of 0.1 to 5; or the ratio of TiO2 to Y2O3 is in the range of 0.1 to 5; or the ratio of TiO2 to the sum of Y2O3 and Al2O3 is in the range of 0.1 to 1; or the ratio of TiO2 to SiO2 is in the range of 0.05 to 1.

[0011] In one aspect, which can be combined with any other aspect or embodiment, the ratio of R2O to Al2O3 is in the range of 0.3 to 0.7; or the ratio of Al2O3 to Y2O3 is in the range of 1 to 4; or the ratio of TiO2 to Y2O3 is in the range of 0.25 to 1.75; or the ratio of TiO2 to the sum of Y2O3 and Al2O3 is in the range of 0.1 to 0.5; or the ratio of TiO2 to SiO2 is in the range of 0.05 to 0.75.

[0012] In one aspect, which can be combined with any other aspect or embodiment, the composition is a glass composition. In one aspect, which can be combined with any other aspect or embodiment, the composition is a glass-ceramic composition.

[0013] In some embodiments, the Young's modulus of the glass composition is in the range of 107 GPa to 126 GPa. In some embodiments, the Young's modulus of the glass-ceramic composition is in the range of 119 GPa to 177 GPa. Description of the Drawings

[0014] In conjunction with the accompanying drawings, the present disclosure can be more fully understood through the following specific embodiments, wherein:

[0015] Figures 1A to 1I Backscattered scanning electron microscopy (SEM) images of Li-only glass-ceramic microstructures are illustrated according to some embodiments.

[0016] Figure 2A and 2B Backscattered SEM images of Na-only glass-ceramic microstructures are illustrated according to some embodiments.

[0017] Figure 3A and 3B Backscattered SEM images of glass-ceramic microstructures containing mixed alkali metals (e.g., containing Li and Na) are illustrated according to some embodiments.

[0018] Figure 4 Backscattered SEM images of glass-ceramic microstructures containing high SiO2, low Al2O3, and low ZrO2 are illustrated according to some embodiments. Specific Embodiments

[0019] In the following description, whenever a group is described as including at least one and combinations of a group of elements, it should be understood that the group can include any number of these listed elements in the form of a single element or a combination of each other, or consist essentially of any number of these listed elements, or consist of any number of these listed elements. Similarly, whenever a group is described as consisting of at least one element or a combination thereof from a group of elements, it should be understood that the group can consist of any number of these listed elements in the form of a single element or a combination of each other. Unless otherwise specified, the recited numerical ranges include both the upper and lower limits of the range, as well as any range between the upper and lower limits. It should also be understood that the various features disclosed in the specification and drawings can be used in any and all combinations.

[0020] If a numerical range including an upper limit value and a lower limit value is recited herein, unless otherwise indicated in specific circumstances, the range is intended to include the endpoints of the range and all integers and fractions within the range. The scope of the claims is not limited to the specific values recited when defining the range. Additionally, when a quantity, concentration, or other numerical value or parameter is given in the form of a range, a list of one or more preferred ranges, or a list of preferred upper limit values and preferred lower limit values, this should be understood to expressly disclose all ranges formed by any pairing of any range upper limit or preferred value with any range lower limit or preferred value, whether or not those pairings are separately disclosed. Finally, when the term “about” is used to describe a value or endpoint of a range, it should be understood that the present disclosure includes the specific value or endpoint being referenced. When the numerical value or endpoint of a range is recited without using “about”, the numerical value or endpoint of the range is intended to include two embodiments: one modified by “about” and the other not modified by “about”.

[0021] In this document, glass and glass - ceramic compositions are expressed in terms of the molar % amounts of the specific components contained therein (based on oxides), unless otherwise indicated. Any component having more than one oxidation state may be present in the glass or glass - ceramic composition in any oxidation state. However, the concentration of such a component is expressed in terms of the oxide in which the component is in its lowest oxidation state, unless otherwise indicated.

[0022] Unless otherwise indicated, all compositions are expressed as mole percentages (mol %). The Young's modulus, shear modulus, and Poisson's ratio are all measured at the same time using resonance ultrasonic spectroscopy as described in ASTM E1875 - 00e1.

[0023] Glass and glass - ceramic compositions

[0024] The novel compositions disclosed herein include mechanically advantageous and ion - exchangeable precursor glasses, and strong, high Young's modulus, high hardness, and ion - exchangeable glass - ceramics. The precursor glasses are unique because they include extremely high Al2O3 and Y2O3 contents, and low SiO2 contents. The glass - ceramics have novel phase compositions and microstructures (e.g., homogeneous nucleation and internal nucleation). Additionally, in addition to their inherent strength, the disclosed glass and glass - ceramic compositions can be chemically strengthened, thereby further increasing their resistance to damage from surface flaws.

[0025] As used herein, “composition” may refer to either “glass composition” or “glass - ceramic composition”. It is expected that the compositions of the precursor glasses and the glass - ceramics after heat - treating the precursor glasses (ceramization) are substantially equivalent (explained below).

[0026] Silicon dioxide (SiO2) is used as the main oxide component of the compositions of the embodiments and may be included therein to provide high-temperature stability and chemical durability. In some instances, the composition may include from 30 mole % to 60 mole % of SiO2. In some instances, the composition may include from 30 mole % to 50 mole % of SiO2. In some instances, the composition may include from 30 mole % to 35 mole % of SiO2, or from 35 mole % to 40 mole % of SiO2, or from 40 mole % to 45 mole % of SiO2, or from 45 mole % to 50 mole % of SiO2, or from 50 mole % to 55 mole % of SiO2, or from 55 mole % to 60 mole % of SiO2, or from 30 mole % to 40 mole % of SiO2, or from 35 mole % to 50 mole % of SiO2, or from 40 mole % to 50 mole % of SiO2, or any value or range disclosed herein. In some instances, the composition is substantially free of SiO2 or includes 30 mole %, 31 mole %, 32 mole %, 33 mole %, 34 mole %, 35 mole %, 36 mole %, 37 mole %, 38 mole %, 39 mole %, 40 mole %, 41 mole %, 42 mole %, 43 mole %, 44 mole %, 45 mole %, 46 mole %, 47 mole %, 48 mole %, 49 mole %, 50 mole % of SiO2, or any range or value having the endpoints disclosed herein.

[0027] Network formers are oxide components of a glass that form the backbone of the glass structure. Some examples include: SiO2, Al2O3, P2O5, and B2O3. Alumina (Al2O3) can affect the structure of the composition and also lower the liquidus temperature and coefficient of thermal expansion, or raise the strain point. In addition to its role as a network former, Al2O3 (and ZrO2) helps improve the chemical durability of silicate-based compositions without toxicity concerns.

[0028] Additionally, alumina (Al2O3) advantageously promotes an increase in the mechanical strength of the composition. The compositions disclosed herein are unique due to their high Al2O3 content. Together with yttrium oxide, one of the most important effects of alumina is that it increases the elastic modulus E (GPa) of the glass or glass-ceramic composition. At least due to the concentration of alumina, glass compositions and glass-ceramic compositions with high Young's modulus values are obtained (Young's modulus is 107 - 126 GPa and 119 - 177 GPa, respectively). Additionally, the glass-ceramic composition also has a high fracture toughness (0.99 - 3.2 MPa*√m) and a high Vickers hardness (868 - 1192 kgf / mm 2 )

[0029] In some instances, the composition may comprise from 15 mole % to 35 mole % of Al2O3. In some instances, the composition may comprise from 18 mole % to 31 mole % of Al2O3. In some instances, the composition may comprise from 15 mole % to 20 mole % of Al2O3, or from 20 mole % to 25 mole % of Al2O3, or from 25 mole % to 30 mole % of Al2O3, or from 30 mole % to 35 mole % of Al2O3, or from 18 mole % to 30 mole % of Al2O3, or from 25 mole % to 31 mole % of Al2O3, or from 18 mole % to 21 mole % of Al2O3, or from 21 mole % to 24 mole % of Al2O3, or from 24 mole % to 27 mole % of Al2O3, or from 27 mole % to 30 mole % of Al2O3, or from 30 mole % to 33 mole % of Al2O3, or from 25 mole % to 35 mole % of Al2O3, or any value or range disclosed herein. In some instances, the composition comprises 15 mole %, 16 mole %, 17 mole %, 18 mole %, 19 mole %, 20 mole %, 21 mole %, 22 mole %, 23 mole %, 24 mole %, 25 mole %, 26 mole %, 27 mole %, 28 mole %, 29 mole %, 30 mole %, 31 mole %, 32 mole %, 33 mole %, 34 mole %, 35 mole % of Al2O3, or any range or value having the endpoints disclosed herein.

[0030] Zirconia (ZrO2) acts as a nucleating agent, which promotes internal nucleation, an important first step in crystallization. In some instances, the composition may comprise from 0 mole % to 10 mole % of ZrO2. In some instances, the composition may comprise from 0 mole % to 5 mole % of ZrO2. In some instances, the composition may comprise from 0 mole % to 4 mole % of ZrO2, or from 0.5 mole % to 3.5 mole % of ZrO2 or from 1 mole % to 3 mole % of ZrO2, or any value or range disclosed herein. In some instances, the composition comprises 0, >0, 0.5 mole %, 1 mole %, 1.5 mole %, 2 mole %, 2.5 mole %, 3 mole %, 3.5 mole %, 4 mole % of ZrO2, or any range or value having the endpoints disclosed herein.

[0031] Alkali metal oxides (R2O, which is the sum of Na2O, K2O, Li2O, Rb2O, and / or Cs2O) are used as aids to achieve low melting temperatures and low liquidus temperatures, and / or contribute to improved bioactivity (if desired), and / or affect the coefficient of thermal expansion, especially at low temperatures. In some instances, the composition may comprise from 0 mole % to 25 mole % of R2O. In some instances, the composition may comprise from 0 mole % to 22 mole % of R2O. In some instances, the composition may comprise a combination of from 0 mole % to 22 mole % of Na2O and Li2O. In some instances, the composition may comprise from 1 mole % to 20 mole %, or from 3 mole % to 17 mole %, or from 4 mole % to 16 mole %, or from 4.5 mole % to 15.5 mole %, or from 5 mole % to 15 mole %, or from 0 mole % to 15 mole % of R2O, or any numerical value or range disclosed herein. In some instances, the composition may comprise from 0 mole % to 15 mole % of Na2O, or from 0 mole % to 12.5 mole % of Na2O, 0 mole % to 10.5 mole % of Na2O, or any numerical value or range disclosed herein. In some instances, the composition may comprise from 0 mole % to 15 mole % of Li2O, or from 0 mole % to 12.5 mole % of Li2O, 0 mole % to 11.5 mole % of Li2O, or any numerical value or range disclosed herein. In some instances, the composition comprises 0, >0, 1 mole %, 2 mole %, 3 mole %, 4 mole %, 5 mole %, 6 mole %, 7 mole %, 8 mole %, 9 mole %, 10 mole %, 11 mole %, 12 mole %, 13 mole %, 14 mole %, 15 mole %, 16 mole %, 17 mole %, 18 mole %, 19 mole %, 20 mole %, 21 mole %, 22 mole %, 23 mole %, 24 mole %, 25 mole % of R2O (e.g., Na2O, K2O, Li2O, Rb2O, Cs2O, or a combination thereof), or any range or numerical value having the endpoints disclosed herein.

[0032] Yttrium oxide (Y2O3) advantageously promotes an increase in the mechanical strength of the composition. The compositions disclosed herein are unique due to their high Y2O3 content. Together with alumina, the most important effect of yttrium oxide is that it increases the elastic modulus E (GPa) of the glass or glass-ceramic composition. At least due to the concentration of yttrium oxide, glass compositions and glass-ceramic compositions with high Young's modulus values are obtained (Young's modulus is 107 - 126 GPa and 119 - 177 GPa, respectively). Additionally, the glass-ceramic composition also has a high fracture toughness (0.99 - 3.2 MPa*√m) and a high Vickers hardness (868 - 1192 kgf / mm 2 )

[0033] For glass compositions, these properties can be due to the high field strength of network modifiers in these glasses. Due to the high field strength, a close-packed structure appears and results in a high modulus, as well as a high density and refractive index. For glass-ceramic compositions, various crystalline phases increase the mechanical properties of the bulk material relative to their precursor glasses (e.g., as explained in Example 4 below). The phases that contribute the most to this increase in mechanical properties are Y2Ti2O7, Y2Si2O7, and Y3Al5O 12 (yttrium aluminum garnet, YAG). The increase in Young's modulus is greatest in compositions containing only Li, but the increase in Young's modulus is still significant for glass-ceramics containing only Na.

[0034] In some instances, the composition can comprise from 5 mol% to 25 mol% of Y2O3. In some instances, the composition can comprise from 8 mol% to 14 mol% of Y2O3. In some instances, the composition can comprise from 10 mol% to 15 mol% of Y2O3. In some instances, the composition can comprise from 7 mol% to 23 mol% of Y2O3 or from 10 mol% to 20 mol% of Y2O3, or any value or range disclosed herein. In some instances, the composition comprises 5 mol%, 6 mol%, 7 mol%, 8 mol%, 9 mol%, 10 mol%, 11 mol%, 12 mol%, 13 mol%, 14 mol%, 15 mol%, 16 mol%, 17 mol%, 18 mol%, 19 mol%, 20 mol%, 21 mol%, 22 mol%, 23 mol%, 24 mol%, 25 mol% of Y2O3, or any range or value having the endpoints disclosed herein.

[0035] Boron trioxide (B2O3) helps to lower the liquidus temperature and increase the amount of residual glass in the glass-ceramic composition. Currently, the liquidus temperature of the compositions disclosed herein is significantly lower than that achieved by other glass-ceramics with comparable high Young's modulus (e.g., enstatite glass-ceramics). In some instances, the composition can comprise from 0 mol% to 5 mol% of B2O3. In some instances, the composition can comprise from 0 mol% to 2.5 mol% of B2O3. In some instances, the composition can comprise from 0 mol% to 1 mol% of B2O3. In some instances, the composition can comprise from 0 mol% to 4 mol% of B2O3, or from 0.5 mol% to 3.5 mol% of B2O3, or from 1 mol% to 3 mol% of B2O3, or any value or range disclosed herein. In some instances, the composition comprises 0, >0, 0.5 mol%, 1 mol%, 1.5 mol%, 2 mol%, 2.5 mol%, 3 mol%, 3.5 mol%, 4 mol%, 4.5 mol%, 5 mol% of B2O3, or any range or value having the endpoints disclosed herein.

[0036] Titanium dioxide (TiO₂) acts as a nucleating agent, which promotes internal nucleation and is an important first step in crystallization. In some examples, the composition may comprise from 0 mol% to 20 mol% of TiO₂. In some examples, the composition may comprise from 5 mol% to 20 mol% of TiO₂. In some examples, the composition may comprise from 4 mol% to 14 mol% of TiO₂. In some examples, the composition may comprise from 4 mol% to 18 mol% of TiO₂, or from 6 mol% to 18 mol% of TiO₂, or from 6 mol% to 16 mol% of TiO₂, or from 8 mol% to 16 mol% of TiO₂, or from 8 mol% to 14 mol% of TiO₂, or any value or range disclosed herein. In some examples, the composition comprises 5 mol%, 6 mol%, 7 mol%, 8 mol%, 9 mol%, 10 mol%, 11 mol%, 12 mol%, 13 mol%, 14 mol%, 15 mol%, 16 mol%, 17 mol%, 18 mol%, 19 mol%, 20 mol% of TiO₂, or any range or value having the endpoints disclosed herein.

[0037] Other compositions may include phosphorus pentoxide (P₂O₅), network modifier alkaline earth metal oxides (MgO, CaO, SrO, and / or BaO), and zinc oxide (ZnO). Phosphorus pentoxide (P₂O₅) can also be used as a network former and helps to increase the viscosity of the composition, thereby expanding the range of operating temperatures and thus being beneficial for the manufacture and formation of glass and / or glass-ceramic compositions. The alkaline earth metal oxides can improve the desired properties in the material, including increasing the Young's modulus and the coefficient of thermal expansion. In some examples, zinc oxide (ZnO) can act similarly to an alkaline earth metal oxide (such as MgO).

[0038] Additional components may be included in the composition to provide additional benefits or may be included as contaminants commonly found in commercially prepared compositions. For example, additional components may be added as colorants or clarifying agents (e.g., to facilitate the removal of gaseous inclusions from the melt batch used to produce the composition) and / or for other purposes. In some examples, the composition may comprise one or more compounds that act as ultraviolet radiation absorbers. In some examples, the composition may comprise CeO, MnO, Nb₂O₅, MoO₃, Ta₂O₅, WO₃, SnO₂, Fe₂O₃, As₂O₃, Sb₂O₃, Cl, Br, or combinations thereof. According to some examples, the composition may also comprise various contaminants associated with the batch materials and / or introduced into the composition due to the melting, clarification, and / or forming equipment used to produce the composition. For example, in some embodiments, the composition may comprise SnO₂ or Fe₂O₃, or a combination thereof.

[0039] In some instances, the composition comprises a combination of SiO2, Al2O3, Y2O3, and TiO2. For example, the composition comprises 30 mol% to 40 mol% SiO2, 25 mol% to 35 mol% Al2O3, 8 mol% to 14 mol% Y2O3, and 4 mol% to 18 mol% TiO2. In some instances, the composition further comprises Li2O, Na2O, and B2O3. For example, the composition comprises 0 mol% to 12.5 mol% Li2O, 0 mol% to 10.5 mol% Na2O, and 0 mol% to 2.5 mol% B2O3.

[0040] In some instances, the composition comprises a combination of SiO2, Al2O3, R2O, Y2O3, and TiO2. For example, the composition comprises 30 mol% to 50 mol% SiO2, 18 mol% to 30 mol% Al2O3, 0 mol% to 22 mol% R2O, 10 mol% to 15 mol% Y2O3, and 4 mol% to 14 mol% TiO2. In some instances, the composition further comprises ZrO2, wherein R2O comprises Li2O and Na2O. For example, the composition comprises 0 mol% to 4 mol% ZrO2, 0 mol% to 11.5 mol% Li2O, and 0 mol% to 10.5 mol% Na2O.

[0041] Examples

[0042] The embodiments described herein are further illustrated by the following examples.

[0043] Example 1 - Precursors Glass Composition Formation

[0044] Glasses having the oxide contents listed in Table 1 can be manufactured by conventional methods. In some instances, the precursor glass can be formed by thoroughly mixing the required batch (e.g., using a tube mixer) to ensure a homogeneous melt, and then placing it into a silica and / or platinum crucible. The crucible can be placed in a furnace and the glass batch melted and held at a temperature of 1100 °C to 1400 °C for a time of about 6 hours to 24 hours. Subsequently, the melt can be poured into a steel mold to obtain glass slabs. Subsequently, the slabs can be immediately transferred to an annealing furnace operating at about 400 °C to 700 °C, where the glass is held at temperature for about 0.5 hours to 3 hours, and then cooled overnight. In another non-limiting example, the precursor glass is prepared by dry mixing the appropriate oxide and mineral sources for a time sufficient to thoroughly mix the components. The glass is melted in a platinum crucible at a temperature of about 1100 °C to about 1400 °C and held at temperature for about 6 hours to 16 hours. The resulting glass melt is then poured onto a steel table for cooling. Subsequently, the precursor glass is annealed at an appropriate temperature.

[0045] The glass compositions for specific implementation can be ground into fine particles of 1 - 10 micrometers (μm) by air jet milling, or can be ground into short fibers. For the glass batch, comminution or ball milling can be used, and the particle size can vary within the range of 1 - 100 μm. Additionally, different methods can be used to process these glasses into short fibers, beads, sheets, or three-dimensional scaffolds. Short fibers are manufactured by melt spinning or electrospinning; beads can be produced by flowing glass particles through a vertical furnace or torch; sheets can be manufactured using thin rolling, float, or fusion drawing processes; and scaffolds can be produced using rapid prototyping techniques, polymer foam replication, and particle sintering.

[0046] Continuous fibers can be easily drawn from the claimed compositions using processes known in the art. For example, using a platinum sleeve directly heated (through which an electric current passes directly), fibers can be formed. Cullet is loaded into the sleeve and heated until the glass can be melted. The temperature is set to achieve the desired glass viscosity (usually < 1000 poise), allowing a drip to form at the orifice in the sleeve (the sleeve size is selected to impose limitations on the possible fiber diameter range). The drip is pulled by hand to start forming the fiber. Once the fiber is produced, it is attached to a rotating draw / collection cylinder to continue the drawing process at a consistent speed. The fiber diameter can be manipulated using the cylinder speed (or revolutions per minute RPM) and the glass viscosity - generally, the faster the draw speed, the smaller the fiber diameter. Glass fibers with diameters in the range of 1 - 100 μm can be continuously drawn from the glass melt. Fibers can also be produced using the up-drawing process. In this process, fibers are drawn from the surface of the glass melt located in a box furnace. By controlling the viscosity of the glass, a quartz rod is used to draw the glass from the melt surface to form fibers. The fiber can be continuously pulled up to increase the fiber length. The speed at which the rod is pulled up and the glass viscosity determine the fiber thickness.

[0047] Example 2 - Precursors Glass Composition

[0048] Table 1 lists non-limiting examples of the amounts of oxides used to form the precursor glass.

[0049]

[0050] Table 1

[0051]

[0052] Table 1 continued

[0053] The ratios of TiO2 to Y2O3, TiO2 to the sum of Y2O3 and Al2O3, and TiO2 to SiO2 represent the ratio of the oxide component (TiO2) allocated to the nucleating microcrystals to (A) another oxide (Y2O3) in the Ti-containing phase; (B) two components (Y2O3 and Al2O3) with similar coordination in the precursor glass; and (C) the glass network former (SiO2). These ratios are important because they describe the balance between the nucleating phase and other crystalline phases. Assuming all R + First, charge balance Al 3+ , then the ratio of R2O to Al2O3 is important for determining the charge balance of the precursor glass. In other words, the ratio of R2O to Al2O3 is important for glass composition design because it represents the charge balance of the composition, which has a significant impact on the composition structure and thus on the composition properties. Charge balance is also important for determining the ease of forming the glass. The ratio of Al2O3 to Y2O3 is important for determining the potential components that can be allocated to the yttrium aluminum garnet (YAG) phase, which is one of the phases that crystallize.

[0054] The glass compositions disclosed herein can be in any form, e.g., particles, powders, microspheres, fibers, sheets, beads, scaffolds, woven fibers.

[0055] Example 3 - Precursors Glass Composition Properties

[0056] The Young's modulus, shear modulus, and Poisson's ratio were all measured at the same time using resonant ultrasound spectroscopy as described in ASTM E1875 - 00e1. Additionally, the ion exchange properties of the glass were carried out in 100% NaNO3 at 450°C. The ion exchange process imparts a compressive stress layer in the glass material, which increases the damage resistance to flaws in this compressive stress layer. The tests and test conditions are to demonstrate that these glass materials are ion - exchangeable.

[0057] A C D E H I J B1 D1 G1 I1 J1 K1 Poisson's ratio 0.266 0.270 0.262 0.263 0.269 0.265 0.263 0.267 0.273 0.258 0.270 0.271 0.265 Young's modulus, E (GPa) 122 123 124 107 118 118 117 122 126 111 125 122 124 Shear modulus, G (GPa) 48.1 48.5 49.2 42.5 46.3 46.7 46.3 48.0 49.6 44.0 49.2 47.8 48.9 <![CDATA[Δ weight % after 4 hours in NaNO3]]> 0.03 0.03 0.05 0.01 0.04 0.08 --- --- --- --- --- --- --- <![CDATA[Δ weight % after 8 hours in NaNO3]]> 0.03 0.04 0.08 --- 0.06 0.12 --- --- --- --- --- --- ---

[0058] Table 2

[0059] The data in Table 2 illustrate that the precursor glass has extremely high Young's modulus values. In contrast, the Young's modulus value of ordinary glass compositions is only about 75 GPa. The low weight change after ion exchange is one way to indicate that the ion exchange has been successfully carried out.

[0060] Example 4 - Glass-Ceramic Composition Properties

[0061] After forming and testing the precursor glasses as described in Examples 1-3, the precursor glasses were subjected to the following heat treatment (i.e., ceramization): (a) a first temperature ramp from room temperature (RT) to the nucleation step temperature at 5 °C / min; (b) a first isothermal hold at the nucleation step temperature for a first predetermined time; (c) a second temperature ramp from the nucleation step temperature to the crystallization step temperature at 5 °C / min; (d) a second isothermal hold at the crystallization step temperature for a second predetermined time; and (e) a final cooling from the crystallization step temperature to room temperature in the furnace at the natural cooling rate.

[0062] Table 3-6 shows the properties of the glass-ceramics formed due to the ceramization treatment. The glass-ceramics were characterized as described in Example 3 above - Young's modulus, shear modulus, Poisson's ratio, and ion exchange capacity. Fracture toughness was measured using methods known in the art, for example, using V-notch, short bar, notched beam, etc., according to ASTM C1421-10. As described in the present disclosure, the fracture toughness value (K 1C ) refers to the value measured by the V-notch short bar (CNSB) method. Vickers hardness was measured using a Vickers indenter and a 200 g load.

[0063]

[0064]

[0065] Table 3

[0066]

[0067]

[0068] Table 4

[0069]

[0070]

[0071] Table 5

[0072]

[0073]

[0074] Table 6

[0075] Example 5 - Backscattered Scanning Electron Microscopy

[0076] Figures 1A to 1I Backscattered scanning electron microscopy (SEM) images illustrating the microstructure of Li-only glass-ceramics are summarized in Table 7 below.

[0077]

[0078]

[0079] Table 7

[0080] As the amount of nucleating agent (TiO2) in the bulk composition increases, nucleation and the resulting crystallization become more uniform (i.e., the crystallization—and the resulting microstructure—is consistent across the test area of the sample material). For example, Figure 1B less uniform. For example, in comparing Figure 1C and Figure 1A and Figure 1C (both held at a nucleation temperature of 850 °C for 2 hours and a crystallization temperature of 950 °C for 4 hours), even though samples A and D both have similar Young's moduli (A: 159.8 GPa; D: 157.3 GPa) and fracture toughnesses (A: 2.07 MPa*√m; D: 2.03 MPa*√m), the microstructure of each is unique and different. The large acicular and globular structures of sample A may contribute to the very high fracture toughness value. Sample A contains half the amount of TiO2 nucleating agent as sample D. In other words, sample A ( Figure 1A ) shows a structure with many random, cross-hatched structures that grow rapidly and, given their random positions in the material, are poorly nucleated. In contrast, sample D ( Figure 1D ) has twice the amount of TiO2 nucleating agent as sample A and, due to increased nucleation, has a finer, more consistent, and uniform structure. A similar trend was observed in comparing Figure 1B and Figure 1D (both held at a nucleation temperature of 850 °C for 2 hours and a crystallization temperature of 1050 °C for 4 hours).

[0081] Figure 2A and 2B illustrate backscattered SEM images of the Na-only glass-ceramic microstructure, which are summarized in Table 8 below.

[0082]

[0083]

[0084] Table 8

[0085] Compared to compositions containing only Li (e.g., those in Table 7), the microstructure of sample E is unique. For the Na-only glass-ceramic microstructure, due to the crystallization temperature from Figure 2AThe structural differences caused by the increase to 2B are not as large as those of the glass-ceramic microstructure containing only Li. For example, the Young's modulus of the ceramization scheme of nucleation at 850 °C for 2 hours and crystallization at 950 °C for 4 hours is 119 GPa, compared to 134 GPa when ceramized at nucleation at 850 °C for 2 hours and crystallization at 1050 °C for 4 hours, an increase of only about 13%. This may be due to two-phase crystallization (less strong) and a weaker microstructure.

[0086] Figure 3A and 3B Backscattered SEM images exemplifying glass-ceramic microstructures containing mixed alkali metals (e.g., containing Li and containing Na) are summarized in Table 9 below. Figure 3A The microstructure of Figure 3B is much finer than that of

[0087]

[0088] Table 9

[0089] As expected, the measured strength properties are between those of the composition containing only Li and the composition containing only Na: Young's modulus of sample D (containing only Li): 157.3 GPa to 174 GPa, sample E (containing only Na): 119 GPa to 134 GPa, and sample I (containing Li and containing Na): 142 GPa to 148 GPa. However, the microstructure is significantly different from either the composition containing only Li or the composition containing only Na.

[0090] Figure 4 Backscattered SEM images exemplifying glass-ceramic microstructures containing high SiO2 (50.0 mol%), low Al2O3 (18.0 mol%) and low ZrO2 (4.0 mol%) are shown. Specifically, Figure 4 Sample J is shown, which was ceramized at a nucleation temperature of 850 °C for 2 hours and a crystallization temperature of 950 °C for 4 hours. The microstructure of sample J is significantly different from the microstructure described in Figures 1A - 3B because it has significantly more globular and needle-like shapes.

[0091] Accordingly, as described herein, novel glass and glass-ceramic compositions having predictable, excellent mechanical properties are disclosed. The mechanical and elastic properties of the glass compositions disclosed herein are superior to many commercially available glass compositions. For example, the Young's modulus of compositions commonly used in hand-held devices, storage disks, and fiber applications is about 65 GPa to 75 GPa, while the Young's modulus range of the glass compositions disclosed herein is significantly higher, between 107 GPa and 126 GPa. These values are high enough such that the precursor glasses of the disclosed glass-ceramics are competitive with many transparent glass-ceramics, which is a significant achievement for a completely amorphous material. Additionally, the precursor glass compositions of the present application can be chemically strengthened (as indicated by preliminary weight gain data), while also having high fracture toughness and hardness.

[0092] After heat treatment, the glass compositions become opaque, forming white glass-ceramics that are even more mechanically favorable (i.e., having higher modulus values) than the precursor glasses. Depending on the composition and the ceramization protocol, the Young's modulus values of the glass-ceramics range from 119 GPa to 177 GPa. Fracture toughness is generally proportional to the Young's modulus, which suggests that these materials also have high fracture toughness, and thus, compared to materials with lower fracture toughness values (e.g., more common glasses), they have improved strength for a given flaw size scale. Finally, these materials also have high hardness - the Vickers hardness ranges from 868 kgf / mm 2 to 1192 kgf / mm 2 . In contrast, the Vickers hardness of common glasses is in the range of 550 kgf / mm 2 to 700 kgf / mm 2 .

[0093] Furthermore, the glass-ceramics provided herein can be chemically strengthened, which increases the depth to which surface flaws can penetrate before failure. After only 4 hours and 8 hours at 450 °C (a low temperature for glass-ceramics), the weight gain is 0.07% - 0.29% to 0.09% - 0.38%. More ion exchange will occur at higher temperatures and longer times, resulting in even higher surface compressive stress and thus higher damage resistance. This damage resistance is crucial for hand-held device applications that use glass / glass-ceramic protective covers.

[0094] As used herein, the term "and / or" when used in a list of two or more items means that any one of the listed items can be used alone, or any combination of two or more of the listed items can be used. For example, if a composition is described as containing components A, B, and / or C, the composition can contain only A; only B; only C; a combination of A and B; a combination of A and C; a combination of B and C; or a combination of A, B, and C.

[0095] Element positions referred to in this document (e.g., "top", "bottom", "above", "below", "first", "second", etc.) are only used to describe the orientations of the various elements in the drawings. It should be noted that the orientations of the various elements may be different according to other exemplary embodiments, and such changes are intended to be covered within the scope of the present disclosure. Additionally, these relative terms are only used to distinguish one entity or action from another entity or action, and do not necessarily require or imply any actual such relationship or order between these entities or actions.

[0096] Those skilled in the art and those who make or use the technology of the present disclosure can make modifications to the present disclosure. Therefore, it should be understood that the embodiments shown in the drawings and described above are only for illustrative purposes and are not intended to limit the scope of the present disclosure. The scope of the present disclosure is defined by the appended claims, as interpreted according to the principles of patent law (including the doctrine of equivalents).

[0097] Those of ordinary skill in the art should understand that the construction of the present disclosure and other components is not limited to any specific material. Unless otherwise stated herein, the other exemplary embodiments of the present disclosure disclosed herein may be formed of various materials.

[0098] As used herein, the terms "about", "approximately", "substantially" and similar terms are intended to have a broad meaning consistent with the ordinary and acceptable usage by those of ordinary skill in the art in the field to which the subject matter of the present disclosure pertains. Those skilled in the art who review the present disclosure should understand that these terms are intended to allow the description of certain features recited and claimed without restricting the scope of these features to the precise numerical ranges provided. Therefore, these terms should be interpreted to mean that non-substantial or minor modifications or variations of the recited and claimed subject matter are considered to be within the scope of the invention as recited in the appended claims. In other words, the terms "about", "approximately", etc. mean that quantities, dimensions, formulas, parameters and other quantities and features are not exact and need not be exact, but may be approximate and / or larger or smaller as required, such as reflecting tolerances, conversion factors, rounding, measurement errors, etc., and other factors known to those skilled in the art.

[0099] Therefore, a glass "free of" or "substantially free of" a certain component means that the component is not actively added or incorporated into the glass, but it may be present in trace amounts [e.g., 500 parts per million (500 ppm), 400 ppm, 300 ppm, 200 ppm or 100 ppm or less] as a contaminant.

[0100] As used herein, terms such as "optional" or "optionally" are intended to mean that the subsequent described event or circumstance may or may not occur, and such description includes instances where the event or circumstance occurs and instances where it does not occur. Unless otherwise specified, the modifier "a", "an" and their corresponding modifier "the" as used herein mean "at least one" or "one or more".

[0101] For substantially any plural and / or singular terms used herein, those skilled in the art can appropriately convert from the plural to the singular form and / or from the singular to the plural form, as long as it is applicable to the context and / or application. For clarity, various singular / plural permutations may be explicitly stated herein.

[0102] Unless otherwise stated, all compositions are expressed as mole percentages (mol%) at the time of compounding. Those of ordinary skill in the art will understand that various molten components (e.g., silicon, alkali metal or alkaline earth metal-based, boron, etc.) may be volatilized to different degrees during component melting (e.g., varying according to vapor pressure, melting time, and / or melting temperature). Therefore, the mole percentage values at the time of compounding used for these components are intended to cover values within ±0.5 wt% of these components in the final, molten article. Considering the above, it is expected that the composition between the final article and the composition at the time of compounding is substantially equivalent. For example, it is expected that the composition between the precursor glass and the glass-ceramic after the heat treatment (ceraming) step is substantially equivalent.

[0103] It will be apparent to those skilled in the art that various modifications and variations can be made without departing from the spirit or scope of the claimed subject matter. Therefore, the claimed subject matter is not limited by anything other than the appended claims and their equivalents.

Claims

1. A composition, which is a glass composition or a glass-ceramic composition, comprising: 30 mol% to 40 mol% of SiO2; 26 mol% to 35 mol% of Al2O3; 8 mol% to 14 mol% of Y2O3; 6 mol% to 18 mol% of TiO2; and 0 mol% to 25 mol% of R2O, Among them, wherein R2O is the sum of Na2O, K2O, Li2O, Rb2O, and Cs2O.

2. The composition according to claim 1, wherein R2O consists of Na2O or Li2O.

3. The composition according to claim 1, wherein R2O contains 0 mol% to 12.5 mol% of Na2O.

4. The composition according to claim 1, wherein R2O contains 0 mol% to 12.5 mol% of Li2O.

5. The composition according to claim 1, further comprising 0 mol% to 2.5 mol% of B2O3.

6. The composition according to claim 1, further comprising 0 mol% to 4 mol% of ZrO2.

7. The composition according to claim 1, comprising: 0 mol% to 12.5 mol% of Li2O; 0 mol% to 10.5 mol% of Na2O; and 0 mol% to 2.5 mol% of B2O3.

8. The composition according to any one of claims 1-7, comprising: 30 mol% to 40 mol% of SiO2; 26 mol% to 30 mol% of Al2O3; 10 mol% to 14 mol% of Y2O3; and 6 mol% to 14 mol% of TiO2.

9. The composition according to claim 8, comprising: 0 mol% to 11.5 mol% of Li2O; 0 mol% to 10.5 mol% of Na2O; and 0 mol% to 4 mol% of ZrO2.

10. The composition according to any one of claims 1-6, wherein: the ratio of R2O to Al2O3 is in the range of 0.1 to 1; or the ratio of Al2O3 to Y2O3 is in the range of 0.1 to 5; or the ratio of TiO2 to Y2O3 is in the range of 0.1 to 5; or the ratio of TiO2 to the sum of Y2O3 and Al2O3 is in the range of 0.1 to 1; or the ratio of TiO2 to SiO2 is in the range of 0.05 to 1.

11. The composition according to claim 10, wherein: the ratio of R2O to Al2O3 is in the range of 0.3 to 0.7; or the ratio of Al2O3 to Y2O3 is in the range of 1 to 4; or the ratio of TiO2 to Y2O3 is in the range of 0.25 to 1.75; or the ratio of TiO2 to the sum of Y2O3 and Al2O3 is in the range of 0.1 to 0.5; or the ratio of TiO2 to SiO2 is in the range of 0.05 to 0.

75.

12. The composition according to any one of claims 1-6, wherein, The composition is a glass composition.

13. The composition according to claim 12, wherein, The Young's modulus of the glass composition is in the range of 107 GPa to 126 GPa.

14. The composition according to any one of claims 1-6, wherein, The composition is a glass-ceramic composition.

15. The composition according to claim 14, wherein, The glass-ceramic composition has a Young's modulus of 119 GPa to 177 GPa.

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