A glass composition includes: 50 mol % to 69 mol % SiO.sub.2; 12.5 mol % to 25 mol % Al.sub.2O.sub.3; 0 mol % to 8 mol % B.sub.2O.sub.3; greater than 0 mol % to 4 mol % CaO; greater than 0 mol % to 17.5 mol % MgO; 0.5 mol % to 8 mol % Na.sub.2O; 0 mol % to 2.5 mol % La.sub.2O.sub.3; and greater than 8 mol % to 18 mol % Li.sub.2O, wherein (Li.sub.2O+Na.sub.2O+MgO)/Al.sub.2O.sub.3 is from 0.9 to less than 1.3; and Al.sub.2O.sub.3+MgO+Li.sub.2O+ZrO.sub.2+La.sub.2O.sub.3+Y.sub.2O.sub.3 is from greater than 23 mol % to less than 50 mol %. The glass composition may be characterized by at least one of the following: a K.sub.1C value measured by a chevron short bar method of at least 0.75; and a K.sub.1C value measured by a double torsion method of at least 0.8. The glass composition is chemically strengthenable. The glass composition may be used in a glass article or a consumer electronic product.

Methods of producing a glass article include melting a first glass composition and feeding a second glass composition into the melter. Both glass compositions include the same combination of components but at least one component has a concentration that is different in each. At least three glass articles may be drawn from the melter, including: a first glass article formed from the first glass composition; at least one intermediate glass article composed of neither the first nor the second glass composition; and a final glass article not composed of the first glass composition. The concentration of the at least one component in the intermediate glass article may be between the concentration in the first and second glass compositions. The first glass article and final glass article may have differing values for certain properties, and the intermediate glass article may have an intermediate set of values for the same properties.

Glass-based articles comprise high effective fracture toughness. Glass-based articles comprise: a glass-based substrate comprising opposing first and second surfaces defining a substrate thickness (t.sub.s), a substantially planar central portion, and a perimeter portion; a polymer coating disposed on at least a portion of at least one of the first or the second surfaces; and an effective fracture toughness that is greater than or equal to 1.25 MPa.Math.m.sup.0.5 as measured at room temperature.

Glass-based articles comprise high effective fracture toughness. Glass-based articles comprise: a glass-based substrate comprising opposing first and second surfaces defining a substrate thickness (t.sub.s), a substantially planar central portion, and a perimeter portion; a polymer coating disposed on at least a portion of at least one of the first or the second surfaces; and an effective fracture toughness that is greater than or equal to 1.25 MPa.Math.m.sup.0.5 as measured at room temperature.

Embodiments of this disclosure pertain to a strengthened glass article including a first surface and a second surface opposing the first surface defining a thickness (t) of about less than about 1.1 mm, a compressive stress layer extending from the first surface to a depth of compression (DOC) of about 0.1.Math.t or greater, such that when the glass article fracture, it breaks into a plurality of fragments having an aspect ratio of about 5 or less. In some embodiments, the glass article exhibits an equibiaxial flexural strength of about 20 kgf or greater, after being abraded with 90-grit SiC particles at a pressure of 25 psi for 5 seconds. Devices incorporating the glass articles described herein and methods for making the same are also disclosed.

Embodiments of this disclosure pertain to a strengthened glass article including a first surface and a second surface opposing the first surface defining a thickness (t) of about less than about 1.1 mm, a compressive stress layer extending from the first surface to a depth of compression (DOC) of about 0.1.Math.t or greater, such that when the glass article fracture, it breaks into a plurality of fragments having an aspect ratio of about 5 or less. In some embodiments, the glass article exhibits an equibiaxial flexural strength of about 20 kgf or greater, after being abraded with 90-grit SiC particles at a pressure of 25 psi for 5 seconds. Devices incorporating the glass articles described herein and methods for making the same are also disclosed.

A thermally tempered aluminosilicate glass-ceramic composition includes a crystalline phase and a residual glass phase, wherein the two phases form a system wherein the thermal expansion curve of the system has two distinct sections diverging from an inflection point temperature in the range of about 450° C. to about 600° C., and wherein the difference between coefficient of thermal expansion of the glass-ceramic below and above the inflection point is greater than about 4 ppm/° C.

A thermally tempered aluminosilicate glass-ceramic composition includes a crystalline phase and a residual glass phase, wherein the two phases form a system wherein the thermal expansion curve of the system has two distinct sections diverging from an inflection point temperature in the range of about 450° C. to about 600° C., and wherein the difference between coefficient of thermal expansion of the glass-ceramic below and above the inflection point is greater than about 4 ppm/° C.

Embodiments of an article comprising a cold-formed glass substrate in a curved shape, a plurality of separate mechanical retainers, and a frame are disclosed. The cold-formed glass substrate has a first major surface, and a second major surface opposing the first major surface. In one more embodiments, the plurality of separate mechanical retainers are attached to the second major surface of the cold-formed glass substrate. The mechanical retainers may be attached to the frame to define a position for each of the plurality of mechanical retainers, such that the mechanical retainers define the curved shape. Embodiments of processes to form such articles are also provided. Such processes can include attaching a plurality of separate mechanical retainers to a flexible glass substrate such that the glass substrate maintains its flexibility, and attaching the mechanical retainers to a frame, such that the mechanical retainers attached to the frame define a cold-formed curved shape for the flexible glass substrate.

Provided is a tempered glass sheet, including: a compressive stress layer having a compressive stress of 20 MPa or more continuously from a main surface in a depth direction thereof; a tensile stress layer that is arranged on an inner side with respect to the compressive stress layer in a sheet thickness direction and has a tensile stress of 20 MPa or more continuously in a depth direction thereof; and a stress-neutral layer arranged between the compressive stress layer and the tensile stress layer, wherein the stress-neutral layer has a compressive stress of less than 20 MPa and/or a tensile stress of less than 20 MPa continuously in the sheet thickness direction, and has a thickness of 5.3% or more of a sheet thickness.