Low CTE glass compositions and glass articles formed from the same are described. In one embodiment, a glass composition includes from about 60 mol. % to about 66 mol. % SiO.sub.2; from about 7 mol. % to about 10 mol. % AI.sub.2O.sub.3; and from about 14 mol. % to about 18 mol. % B.sub.2O.sub.3 as glass network formers. The glass composition may further include from about 9 mol. % to about 16 mol. % alkaline earth oxide. The alkaline earth oxide includes at least CaO. The CaO may be present in the glass composition in a concentration from about 3 mol. % to about 12 mol. %. The glass composition is free from alkali metals. The glass composition has a coefficient of thermal expansion which is less than or equal to 40×10.sup.−7/° C. averaged over the temperature range from about 20° C. to 300° C. The glass composition is particularly well suited for use as a glass cladding layer in a laminated glass article.

Low CTE glass compositions and glass articles formed from the same are described. In one embodiment, a glass composition includes from about 60 mol. % to about 66 mol. % SiO.sub.2; from about 7 mol. % to about 10 mol. % AI.sub.2O.sub.3; and from about 14 mol. % to about 18 mol. % B.sub.2O.sub.3 as glass network formers. The glass composition may further include from about 9 mol. % to about 16 mol. % alkaline earth oxide. The alkaline earth oxide includes at least CaO. The CaO may be present in the glass composition in a concentration from about 3 mol. % to about 12 mol. %. The glass composition is free from alkali metals. The glass composition has a coefficient of thermal expansion which is less than or equal to 40×10.sup.−7/° C. averaged over the temperature range from about 20° C. to 300° C. The glass composition is particularly well suited for use as a glass cladding layer in a laminated glass article.

Methods for producing glass articles from laminated glass tubing include introducing the glass tubing to a converter. The glass tubing includes a core layer under tensile stress, an outer clad layer under, and an inner clad layer. The methods include forming a feature the glass article at a working end of the laminated glass tubing and separating a glass article from the working end of the laminated glass tubing, which may expose the core layer under tensile stress at the working end of the glass tubing. The method further comprises remediating the exposed portion of the core layer by completely enclosing the core layer in a clad layer. Systems for re-cladding the exposed portion of the core layer as well as glass articles made using the systems and methods are also disclosed.

Methods for manufacturing glass articles having a target effective coefficient of thermal expansion CTE.sub.Teff averaged over a temperature range comprise selecting a glass core composition having an average core glass coefficient of thermal expansion CTE.sub.core that is greater than the target effective CTE.sub.Teff and a glass clad composition having an average clad glass coefficient of thermal expansion CTE.sub.clad that is less than the target effective CTE.sub.Teff; and manufacturing a glass laminate comprising a glass core layer formed from the glass core composition and two or more glass cladding layers fused to the glass core layer, each of the two or more glass cladding layers formed from the glass clad composition such that a ratio of a thickness of the glass core layer to a total thickness of the two or more glass cladding layers is selected to produce the glass laminate having an effective coefficient of thermal expansion CTE.sub.eff that is within ±0.5 ppm/° C. of the target effective CTE.sub.Teff.

Methods for manufacturing glass articles having a target effective coefficient of thermal expansion CTE.sub.Teff averaged over a temperature range comprise selecting a glass core composition having an average core glass coefficient of thermal expansion CTE.sub.core that is greater than the target effective CTE.sub.Teff and a glass clad composition having an average clad glass coefficient of thermal expansion CTE.sub.clad that is less than the target effective CTE.sub.Teff; and manufacturing a glass laminate comprising a glass core layer formed from the glass core composition and two or more glass cladding layers fused to the glass core layer, each of the two or more glass cladding layers formed from the glass clad composition such that a ratio of a thickness of the glass core layer to a total thickness of the two or more glass cladding layers is selected to produce the glass laminate having an effective coefficient of thermal expansion CTE.sub.eff that is within ±0.5 ppm/° C. of the target effective CTE.sub.Teff.

A laminated glass article has a first layer having a first ion exchange diffusivity, D.sub.0, and a second layer adjacent to the first layer and having a second ion exchange diffusivity, D.sub.1. D.sub.0/D.sub.1 is from about 1.2 to about 10, or D.sub.0/D.sub.1 is from about 0.05 to about 0.95. A method for manufacturing the laminated glass article includes forming a first layer having a first ion exchange diffusivity, D.sub.0, and forming a second layer adjacent to the first layer and having a second ion exchange diffusivity, D.sub.1. The laminated glass article can be strengthened by an ion exchange process to form a strengthened laminated glass article having a compressive stress layer with a depth of layer from about 8 μm to about 100 μm.

A laminated glass article has a first layer having a first ion exchange diffusivity, D.sub.0, and a second layer adjacent to the first layer and having a second ion exchange diffusivity, D.sub.1. D.sub.0/D.sub.1 is from about 1.2 to about 10, or D.sub.0/D.sub.1 is from about 0.05 to about 0.95. A method for manufacturing the laminated glass article includes forming a first layer having a first ion exchange diffusivity, D.sub.0, and forming a second layer adjacent to the first layer and having a second ion exchange diffusivity, D.sub.1. The laminated glass article can be strengthened by an ion exchange process to form a strengthened laminated glass article having a compressive stress layer with a depth of layer from about 8 μm to about 100 μm.

An aluminoborosilicate glass includes alkaline earth oxides and is substantially free of alkali oxides. The glass may be fusion formable and may be useful as a substrate or other article, such as with consumer and commercial electronic devices.

Glass-based articles having defined stress profiles and methods for manufacturing such glass-based articles are provided. A non-limiting glass-based article comprises an outer region extending from the surface to a depth of compression, wherein the outer region is under a neutral stress or a first compressive stress, a core region under a second compressive stress, the second compressive stress defining a compression peak having a maximum compression value and a maximum width at zero stress in a range of from about 1 micrometer to about 200 micrometers, and an intermediate region disposed between the surface and the core region, wherein the intermediate region is under a tensile stress.

An aluminoborosilicate glass includes alkaline earth oxides and is substantially free of alkali oxides. The glass may be fusion formable and may be useful as a substrate or other article, such as with consumer and commercial electronic devices.