A strengthened glass article (100), such as a substrate for a p-Si based transistors, includes first and second glass cladding layers (104, 106) and a glass core layer (102) disposed therebetween. A coefficient of thermal expansion [CTE] of each cladding layer (104, 106), which can be made of the same glass, is at least 1×10.sup.−7° C..sup.−1 less than that of the core layer (102). Each of the core and cladding layers has a strain point less than 700° C. A compaction of the glass article (100) is at most about 20 ppm [see FIG. 1]. A method includes forming a glass article and/or heating a glass article to a first temperature of at least about 400° C. The glass article has a glass core layer (102) and a glass cladding layer (104, 106) adjacent to the core layer. The glass article is maintained at a temperature within a range of from 400° C. to 600° C. for a holding period from 30 to 90 minutes and subsequently cooled to a temperature of at most 50° C. over a cooling period from 30 seconds to 5 minutes. The glass article (100) for heat strengthening may have been produced by the fusion overflow down draw process, e.g. as depicted in FIG. 3.

A strengthened glass article (100), such as a substrate for a p-Si based transistors, includes first and second glass cladding layers (104, 106) and a glass core layer (102) disposed therebetween. A coefficient of thermal expansion [CTE] of each cladding layer (104, 106), which can be made of the same glass, is at least 1×10.sup.−7° C..sup.−1 less than that of the core layer (102). Each of the core and cladding layers has a strain point less than 700° C. A compaction of the glass article (100) is at most about 20 ppm [see FIG. 1]. A method includes forming a glass article and/or heating a glass article to a first temperature of at least about 400° C. The glass article has a glass core layer (102) and a glass cladding layer (104, 106) adjacent to the core layer. The glass article is maintained at a temperature within a range of from 400° C. to 600° C. for a holding period from 30 to 90 minutes and subsequently cooled to a temperature of at most 50° C. over a cooling period from 30 seconds to 5 minutes. The glass article (100) for heat strengthening may have been produced by the fusion overflow down draw process, e.g. as depicted in FIG. 3.

A laminated or single layer glass cylinder and its method of making are disclosed. The laminated cylinder glass is a precursor component to enable making subsequent drawn tubing having high optical quality. The laminated cylinder glass may comprise a first layer of glass as a clad glass and a second layer of glass as a core glass. The second layer of glass may be bound to the first layer of glass. The second layer may have a higher CTE from about 5×10.sup.−7/° C. to about 100×10.sup.−7/° C. than the first layer of glass. The first layer and second layer of glass may have different softening points within about 200° C. of each other. In some embodiments, the first layer and second layer of glass may have different softening points from about 50° C. to about 200° C. of each other.

A laminate sheet article including: a core including an electrical semi-conductor or an electrical conductor; and a continuous glass clad layer on at least four of six sides the core of the sheet article. Also disclosed is an apparatus for making a sheet laminate article as defined herein. Also disclosed is a method of making and using the article.

A laminate sheet article including: a core including an electrical semi-conductor or an electrical conductor; and a continuous glass clad layer on at least four of six sides the core of the sheet article. Also disclosed is an apparatus for making a sheet laminate article as defined herein. Also disclosed is a method of making and using the article.

A glass-based article comprising a thickness t; a first clad layer having a first thickness t.sub.C1; a second clad layer having a first thickness t.sub.C2; and a core layer having a first thickness t.sub.o, which core layer is disposed between and bonded to the first and second clad layers. A first compressive stress region extends from a surface of the first clad layer to a first depth of compression DOC.sub.1. A second compressive stress region extends from a surface of the second clad layer to a second depth of compression DOC.sub.2. The first and second compressive stress regions comprise a maximum compressive stress greater than or equal to 500 MPa. A central tension region extends from DOC.sub.1 to DOC.sub.2 and has a maximum central tension CT greater than or equal to 250 MPa. A difference in flaw sizes that produce delayed fracture is less than or equal to 3 μm.

A laminated glass article having a core layer made from a glass that is not ion-exchangeable, and a clad layer made from a glass that is ion-exchangeable. The laminated glass article has a maximum compressive stress in the clad layer from about 0.05 GPa to about 0.7 GPa, and a compressive stress at an inner surface of the clad layer directly adjacent to the core layer from about 20% to about 45% of a compressive stress at an outer surface of the clad layer. A slope of a stress profile in the clad layer is substantially linear. Methods for manufactured such a laminated glass article also are disclosed.

An apparatus for forming laminated sheet glass, including: a lower pipe and a first upper pipe separated by a first gap on one side and second gap on the other side, the apparatus being configured so that the position of the lower pipe relative to the first upper pipe are each independently adjustable to control the dimensions of the first gap, the second gap, or both, as defined herein. Also disclosed is a method for forming laminated sheet glass or articles thereof using the aforementioned glass laminating apparatus, as defined herein.

An apparatus for forming laminated sheet glass, including: a lower pipe and a first upper pipe separated by a first gap on one side and second gap on the other side, the apparatus being configured so that the position of the lower pipe relative to the first upper pipe are each independently adjustable to control the dimensions of the first gap, the second gap, or both, as defined herein. Also disclosed is a method for forming laminated sheet glass or articles thereof using the aforementioned glass laminating apparatus, as defined herein.

A laminated glass article includes a core layer and a clad layer directly adjacent to the core layer. The core layer is formed from a core glass composition. The clad layer is formed from a clad glass composition. An average clad coefficient of thermal expansion (CTE) is less than an average core CTE such that the clad layer is in compression and the core layer is in tension. A compressive stress of the clad layer decreases with increasing distance from an outer surface of the clad layer within an outer portion of the clad layer and remains substantially constant with increasing distance from the outer surface of the clad layer within an intermediate portion of the clad layer disposed between the outer portion and the core layer. A thickness of the intermediate portion of the clad layer is at least about 82% of a thickness of the clad layer,