Glass-based articles having stress profiles with high stored energy and methods of manufacture

A glass-based article having a surface and a thickness (t), the glass-based article comprising:

• an outer region extending from the surface to a depth of compression, wherein the outer region is under neutral stress or a first compressive stress;
• a core region under a second compressive stress, the core region including a mid-point between the surface and a second surface opposite the surface of the glass-based article, the second compressive stress defining a compression peak having a maximum compression value and a maximum width such that there is an aspect ratio of the maximum compression value in MPa to the maximum width in microns that is greater than 2:1;
• and
• an intermediate region disposed between the surface and the core region, wherein the intermediate region is under a tensile stress, wherein the glass-based article has a stress profile that results in stored energy in the glass-based article that prevents cracks formed by surface-induced damage from penetrating through the entire thickness of the glass-based article.

A method of making a glass-based article comprising:

• providing a first glass-based substrate having a surface, a thickness (t1), and an outer region extending from the surface to a depth of compression, wherein the outer region has a first compressive stress at the surface and a decreasing stress region such that the first glass-based substrate has a parabolic stress profile;
• providing a second glass-based substrate having a surface, a thickness (t2), and an outer region extending from the surface to a depth of compression, wherein the outer region has a second compressive stress at the surface and a decreasing stress region such that the second glass-based substrate has a parabolic stress profile;
• and
• bonding the first glass-based substrate and the second glass-based substrate together at a bonding interface to provide the glass-based article having a compression peak in a central region of the glass-based article including the bonding interface.

A glass-based article having a surface, a thickness (t) and an edge defining a perimeter, the glass-based article comprising:

• a core region under compressive stress disposed between two cladding regions under tensile stress, wherein the glass-based article is formed from a glass-based composition, and the compressive stress and the tensile stress are such that the glass based article comprises a tensile-strain energy TSE defined by the equation:
• TSE
• =
• (
• 1
• -
• v
• )
• 2
• 
• E
• [
• ∫
• tensile
• 
• 
• σ
• x
• 
• (
• z
• )
• 
• σ
• x
• 2
• 
• (
• z
• )
• 
• dz
• +
• ∫
• tensile
• 
• 
• σ
• y
• 
• (
• z
• )
• >
• 0
• 
• σ
• y
• 2
• 
• (
• z
• )
• 
• dz
• ]
• where ν is the Poisson's ratio of the glass-based composition, E is Young's modulus of the glass-based composition, z is a coordinate along the thickness, x and y are two mutually orthogonal directions in the surface of the glass-based article, σx≡σxx and σy≡σyy are the components of stress along x and y.

A glass-based article having a surface, a thickness (t) and an edge defining a perimeter, the glass-based article comprising:

• a core region under compressive stress disposed between two cladding regions under tensile stress, wherein the compressive stress and the tensile stress are such that the glass based article comprises a tensile-stress intensity parameter Kt defined by the equation:
• K
• t
• =
• ∫
• tensile
• 
• 
• σ
• 
• (
• z
• )
• 
• σ
• 2
• 
• (
• z
• )
• 
• dz
• wherein parameter Kt has units of MPa×√{square root over (m)}.