Abstract: A glass-ceramic comprising, in weight percent on an oxide basis, of 50 to 70% SiO2, 0 to 20% Al2O3, 12 to 23% MgO, 0 to 4% Li2O, 0 to 10% Na2O, 0 to 10% K2O, 0 to 5% ZrO2, and 2 to 12% F, wherein the predominant crystalline phase of said glass-ceramic is a trisilicic mica, a tetrasilicic mica, or a mica solid solution between trisilicic and tetrasilicic, and wherein the total of Na2O+Li2O is at least 2 wt. %; wherein the glass-ceramic can be ion-exchanged.

Abstract: Glass-based articles are provided that exhibit improved fracture resistance. The relationships between properties attributable to the glass composition and stress profile of the glass-based articles are provided that indicate improved fracture resistance.

Abstract: A glass-based article may include from about 45 mol. % to about 80 mol. % SiO2; from about 0 mol. % to about 10 mol. % Na2O; less than about 5 mol. % K2O; a non-zero amount of Al2O; and an amorphous phase and a crystalline phase. The article may further in include a stress profile comprising a surface compressive stress (CS) and a maximum central tension (CT). A ratio of Li2O (mol. %) to R2O (mol. %) in the article is from about 0.5 to about 1, where R2O is the sum of Li2O, Na2O, and K2O in the article. CT may be greater than or equal to about 50 MPa and less than about 100 MPa. CS may be greater than 2.0·CT. A depth of compression (DOC) of the stress profile may be greater than or equal to 0.14·t and less than or equal to 0.25·t, where t is the thickness of the article.

Abstract: A group of glass compositions in the Li2O—Al2O3—SiO2—B2O3 family that can be chemically strengthened in single or multiple ion exchange baths containing at least one of NaNO3 and KNO3 for a short time (2-4 hours) to develop a deep depth of layer (DOL). In some instances, the DOL is at least 70 ?m; in others, at least about 100 ?m. The ion exchanged glasses have a high damage resistance (indentation fracture toughness ranging form greater than 10 kgf to greater than 50 kgf) that is better than or at least comparable to that of sodium aluminosilicate glasses.

Abstract: According to one embodiment, a glass article may include SiO2, Al2O3, Li2O and Na2O. The glass article may have a softening point less than or equal to about 810° C. The glass article may also have a high temperature CTE less than or equal to about 27×10?6/° C. The glass article may also be ion exchangeable such that the glass has a compressive stress greater than or equal to about 600 MPa and a depth of layer greater than or equal to about 25 ?m after ion exchange in a salt bath comprising KNO3 at a temperature in a range from about 390° C. to about 450° C. for less than or equal to approximately 15 hours.

Abstract: A glass-ceramic article comprises: a center-volume composition comprising (on an oxide basis): 55-75 mol % SiO2; 0.2-10 mol % Al2O3; 0-5 mol % B2O3; 15-30 mol % Li2O; 0-2 mol % Na2O; 0-2 mol % K2O; 0-5 mol % MgO; 0-2 mol % ZnO; 0.2-3.0 mol % P2O5; 0.1-10 mol % ZrO2; 0-4 mol % TiO2; and 0-1.0 mol % SnO2. Lithium disilicate and either ?-spodumene or ?-quartz are the two predominant crystalline phases (by weight) of the glass-ceramic article. The glass-ceramic article further comprises tetragonal ZrO2 as a crystalline phase. The composition of the glass-ceramic article from a primary surface into a thickness of the glass-ceramic article can comprise over 10 mol % Na2O (on an oxide basis), with the mole percentage of Na2O decreasing from the primary surface towards the center-volume. The glass-ceramic article exhibits a ring-on-ring load-to-failure of at least 120 kgf, when the thickness of the glass-ceramic article is 0.3 mm to 2.0 mm.

Abstract: Ion-exchanged glass ceramic articles described herein have a stress that decreases with increasing distance according to a substantially linear function from a depth of about 0.07t to a depth of about 0.26t from the outer surface of the ion-exchanged glass ceramic article from a compressive stress to a tensile stress. The stress transitions from the compressive stress to the tensile stress at a depth of from about 0.18t to about 0.25t from the outer surface of the ion-exchanged glass ceramic article. An absolute value of a maximum compressive stress at the outer surface of the ion-exchanged glass article is from 1.8 to 2.2 times an absolute value of a maximum central tension (CT) of the ion-exchanged glass article, and the glass ceramic article has a fracture toughness of 1 MPa?m or more as measured according to the double cantilever beam method.

Abstract: A transparent gahnite-spinel glass ceramic is provided. The glass ceramic includes a first crystal phase including (MgxZn1?x)Al2O4 where x is less than 1 and a second crystal phase including tetragonal ZrO2. The glass ceramic may be ion exchanged. Methods for producing the glass ceramic are also provided.

Abstract: A group of glass compositions in the Li2O—Al2O3—SiO2—B2O3 family that can be chemically strengthened in single or multiple ion exchange baths containing at least one of NaNO3 and KNO3 for a short time (2-4 hours) to develop a deep depth of layer (DOL). In some instances, the DOL is at least 70 ?m; in others, at least about 100 ?m. The ion exchanged glasses have a high damage resistance (indentation fracture toughness ranging form greater than 10 kgf to greater than 50 kgf) that is better than or at least comparable to that of sodium aluminosilicate glasses.

Abstract: A glass-based article includes an amorphous phase and a crystalline phase, and a first surface and a second surface opposing the first surface thereby defining a thickness (t) of the glass-based article. The glass-based article has a stress profile with a surface compressive stress (CS) and a maximum central tension (CT). The maximum CT is greater than or equal to 80 MPa and less than or equal to 95 MPa, and the maximum CT is positioned within the glass-based article at a range from greater than or equal to 0.4·t and less than or equal to 0.6·t. The surface CS of the glass-based article is greater than or equal to 200 MPa; and a depth of compression (DOC) is from greater than or equal to 0.14·t and less than or equal to 0.25·t.

Abstract: In embodiments, a lithium-containing aluminosilicate glass-ceramic article includes a fracture toughness of 1 MPa·m1/2 or greater; a ring-on-ring strength of at least 300 MPa; a compressive stress layer formed by ion-exchange having a depth of layer (DOL) of at least about 30 ?m; and a transmittance of at least 85% for light in a wavelength range from 400 nm to 700 nm at a thickness of 1 mm. The lithium-containing aluminosilicate glass-ceramic article is not frangible.

Abstract: Glass and glass ceramic compositions having a combination of lithium silicate and petalite crystalline phases along with methods of making the glass and glass ceramic compositions are described. The compositions are compatible with conventional rolling and float processes, are transparent or translucent, and have high mechanical strength and fracture resistance. Further, the compositions are able to be chemically tempered to even higher strength glass ceramics that are useful as large substrates in multiple applications.

Abstract: A glass article including, on an oxide basis, from 60 mol % to 74 mol % SiO2, from 7 mol % to 18 mol % Al2O3, from 3 mol % to 16 mol % B2O3, from 0 mol % to 6 mol % Na2O, from 0 mol % to 5 mol % P2O5, from 5 mol % to 11 mol % Li2O, less than or equal to 0.2 mol % SnO2, and from 0.5 mol % to 6.5 mol % divalent cation oxides. The glass article has a molar ratio of Al2O3:(R2O+RO) greater than or equal to 0.9, where R2O is a sum of alkali metal oxides in mol % and RO is a sum of divalent cation oxides in mol %.

Abstract: A black lithium silicate glass ceramic is provided. The glass ceramic includes lithium silicate as a primary crystal phase and at least one of petalite, ?-quartz, ?-spodumene, cristobalite, and lithium phosphate as a secondary crystal phase. The glass ceramic is characterized by the color coordinates: L*: 20.0 to 40.0, a*: ?1.0 to 1.0, and b*: ?5.0 to 2.0. The glass ceramic may be ion exchanged. Methods for producing the glass ceramic are also provided.

Abstract: Glass and glass ceramic compositions having a combination of lithium silicate and petalite crystalline phases along with methods of making the glass and glass ceramic compositions are described. The compositions are compatible with conventional rolling and float processes, are transparent or translucent, and have high mechanical strength and fracture resistance. Further, the compositions are able to be chemically tempered to even higher strength glass ceramics that are useful as large substrates in multiple applications.

Abstract: Glass-based articles are provided that exhibit improved fracture resistance. The relationships between properties attributable to the glass composition and stress profile of the glass-based articles are provided that indicate improved fracture resistance.

Abstract: According to one embodiment, a glass article may include SiO2, Al2O3, Li2O and Na2O. The glass article may have a softening point less than or equal to about 810° C. The glass article may also have a high temperature CTE less than or equal to about 27×10?6/° C. The glass article may also be ion exchangeable such that the glass has a compressive stress greater than or equal to about 600 MPa and a depth of layer greater than or equal to about 25 ?m after ion exchange in a salt bath comprising KNO3 at a temperature in a range from about 390° C. to about 450° C. for less than or equal to approximately 15 hours.

Abstract: A glass article including, on an oxide basis, from 60 mol % to 74 mol % SiO2, from 7 mol % to 18 mol % Al2O3, from 3 mol % to 16 mol % B2O3, from 0 mol % to 6 mol % Na2O, from 0 mol % to 5 mol % P2O5, from 5 mol % to 11 mol % Li2O, less than or equal to 0.2 mol % SnO2, and from 0.5 mol % to 6.5 mol % divalent cation oxides. The glass article has a molar ratio of Al2O3:(R2O+RO) greater than or equal to 0.9, where R2O is a sum of alkali metal oxides in mol % and RO is a sum of divalent cation oxides in mol %.

Abstract: Ion-exchanged glass ceramic articles described herein have a stress that decreases with increasing distance according to a substantially linear function from a depth of about 0.07 t to a depth of about 0.26 t from the outer surface of the ion-exchanged glass ceramic article from a compressive stress to a tensile stress. The stress transitions from the compressive stress to the tensile stress at a depth of from about 0.18 t to about 0.25 t from the outer surface of the ion-exchanged glass ceramic article. An absolute value of a maximum compressive stress at the outer surface of the ion-exchanged glass article is from 1.8 to 2.2 times an absolute value of a maximum central tension (CT) of the ion-exchanged glass article, and the glass ceramic article has a fracture toughness of 1 MPa?m or more as measured according to the double cantilever beam method.

Abstract: A glass article including any one or several of SiO2, Al2O3, B2O3, Li2O, SnO2 and a fusion line. The glass article can also include a liquidus viscosity less than or equal to 100 kP. In some embodiments, the glass article includes, on an oxide basis, from 60 mol % to 74 mol % SiO2, from 7 mol % to 18 mol % Al2O3, from 3 mol % to 16 mol % B2O3, from 0 mol % to 6 mol % Na2O, from 0 mol % to 5 mol % P2O5, from 5 mol % to 11 mol % Li2O, less than or equal to 0.2 mol % SnO2.