| 主权项 |
1. A strengthened glass or glass-ceramic article, comprising:
a first surface, a second surface, and a body extending therebetween, wherein the second surface is on an opposite side of the body from the first surface such that a thickness of the strengthened glass or glass-ceramic article is defined as a distance between the first and second surfaces, a width of the strengthened glass or glass-ceramic article is defined as a first dimension of one of the first or second surfaces orthogonal to the thickness, and a length of the strengthened glass or glass-ceramic article is defined as a second dimension of one of the first or second surfaces orthogonal to both the thickness and the width;
wherein the length of the strengthened glass or glass-ceramic article is greater than or equal to the width;wherein at least one of the first or second surfaces has a relatively large surface area, that being at least 2500 mm2; andwherein the strengthened glass or glass-ceramic article is thin such that the width is greater than five times the thickness; a stress profile of the strengthened glass or glass-ceramic article, wherein, at room temperature of 25° C. and standard atmospheric pressure, an interior portion of the strengthened glass or glass-ceramic article is under positive tensile stress and portions of the strengthened glass or glass-ceramic article exterior to and adjoining the interior portion are under negative tensile stress, whereby the negative tensile stress at least in part fortifies the strengthened glass or glass-ceramic article by limiting initiation and/or propagation of cracks therethrough;
wherein a difference in peak values of the positive and negative tensile stresses is at least 200 MPa; andwherein, despite the relatively large surface area and thin thickness of the strengthened glass or glass-ceramic article, tensile stress in the stress profile sharply transitions between the positive tensile stress of the interior portion and the negative tensile stress of the portions exterior to and adjoining the interior portion such that a rate of change of the tensile stress is at least 200 MPa divided by a distance of 500 μm; and composition of the strengthened glass or glass-ceramic article, wherein the composition comprises (a) an amorphous, non-crystalline solid or (b) a polycrystalline solid comprising an amorphous phase and one or more crystalline phases; and
wherein the composition comprises silicon dioxide;wherein the composition of the strengthened glass or glass-ceramic article located in at least a part of the portions of the strengthened glass or glass-ceramic article exterior to and adjoining the interior portion, under the negative tensile stress, is the same in terms of ion content and chemical constituency as the composition located in at least a part of the interior portion, under the positive tensile stress, such that at least some of the negative tensile stress of the stress profile is independent of a change in the composition of the strengthened glass or glass-ceramic article. |
