阅读说明：本技术 制造经涂覆的基于玻璃的部件的方法 (Method for producing a coated glass-based component ) 是由 I·Z·阿迈德 J·T·哈里斯 胡广立 S·S·朱彼 于 2018-11-29 设计创作，主要内容包括：制造具有涂层和目标形状的基于玻璃的制品,所述目标形状包括：平面中心部分和周界部分,所述周界部分与至少一部分的平面中心部分接壤且从平面中心部分的平面向外延伸,所述周界部分具有周界边缘和边缘到相对边缘的目标尺寸。方法包括：形成基于玻璃的部件以提供初始形成的部件,所述初始形成的部件的初始三维形状与目标形状至少对于边缘到相对边缘的目标尺寸而言是不同的。向初始形成的部件施涂涂层以形成具有涂层的基于玻璃的制品,涂层向初始模制的部件赋予了应力,这导致初始形状发生经过计算的弯曲诱发的变化。(Producing a glass-based article having a coating and a target shape, the target shape comprising: a planar central portion and a perimeter portion bordering at least a portion of the planar central portion and extending outwardly from a plane of the planar central portion, the perimeter portion having a perimeter edge and a target dimension from the edge to an opposite edge. The method comprises the following steps: forming a glass-based part to provide an initially-formed part having an initial three-dimensional shape that is different from a target shape at least for a target dimension from an edge to an opposite edge. Applying a coating to the initially formed part to form a glass-based article having a coating that imparts a stress to the initially molded part that results in a calculated bend-induced change to the initial shape.)

1. A method of making a glass-based article, comprising:

forming a glass-based component comprising an initial shape that is different from a target shape at least for a target dimension from edge to opposite edge, the initial shape comprising a planar central portion and a perimeter portion bordering at least a portion of the planar central portion, the perimeter portion comprising a perimeter edge; and

applying a coating to the formed glass-based component, the coating imparting a stress that results in a calculated bend-induced change in the initial shape.

2. The method of claim 1, wherein the initial shape comprises a three-dimensional shape including a planar central portion and a perimeter portion bordering at least a portion of the planar central portion and extending outward from a plane of the planar central portion.

3. The method of claim 2, wherein the target shape is flat.

4. The method of claim 2 or 3, wherein forming the glass-based article comprises forming the glass-based article in a mold having a molding surface, and wherein the molding surface is designed and dimensioned to compensate for the calculated bend-induced variation of the initial shape such that the coated glass-based article comprises a target shape and a target dimension edge-to-opposing edge.

5. The method of claim 4, wherein the target shape is three-dimensional and includes a planar central portion and a perimeter portion bordering at least a portion of the planar central portion and extending outwardly from a plane of the planar central portion.

6. The method of any of claims 1-5, wherein the coating imparts a compressive stress on the formed part.

7. The method of any of claims 1-5, wherein the coating imparts a tensile stress on the formed part.

8. The method of any one of claims 1-7, wherein the calculated bend-induced change of the initial shape is determined by modeling.

9. The method of claim 8, wherein modeling comprises finite element analysis.

10. The method of any of claims 1-9, wherein the initially formed part comprises a substrate selected from the group consisting of: a laminated glass-based substrate, an ion-exchangeable glass-based substrate, a thermally strengthened glass-based substrate, and combinations thereof.

11. The method of any of claims 1-10, wherein the initially formed part comprises an ion-exchangeable glass-based substrate.

12. The method of any of claims 1-10, wherein the glass-based article comprises an ion-exchangeable alkali aluminosilicate glass composition.

13. The method of any of claims 1-10, wherein the glass-based article comprises an ion-exchangeable alkali aluminoborosilicate glass composition.

14. The method of claim 11, further comprising ion-exchange strengthening the ion-exchangeable glass-based substrate to strengthen the ion-exchangeable glass-based substrate prior to coating.

15. The method of claim 14, wherein the ion-exchange strengthening forms a surface compressive stress of 100MPa to 1100MPa in an outer region of the ion-exchangeable glass-based substrate.

16. The method of claim 14, wherein the ion-exchange strengthening forms a surface compressive stress of 600MPa to 1100MPa in an outer region of the ion-exchangeable glass-based substrate.

17. The method of any of claims 14-16, wherein modeling further comprises calculating a change in initial shape due to ion exchange strengthening of the ion-exchangeable glass-based substrate.

18. The method of any of claims 1-17, wherein the coating imparts a compressive stress of 100MPa to 950 MPa.

19. The method of any one of claims 1-18, wherein the coating has a thickness of 5 nanometers to 5 micrometers.

20. The method of any of claims 1-18, wherein the coating has a thickness of 10 nanometers to 2 micrometers.

21. A method of making a glass-based article, comprising:

forming an initial molded part with a mold comprising a molding surface, the initial molded part comprising a pre-coated three-dimensional shape comprising a planar central portion and a perimeter portion bordering at least a portion of the planar central portion and extending outwardly from the plane of the planar central portion such that the initial molded part has three-dimensional characteristics, the perimeter portion comprising a perimeter edge and a pre-coated edge to opposing edge dimensions; and

coating the initial molded part with a coating to form the glass-based article, the coating imparting a stress on the initial molded part that bends the initial molded part and alters a pre-coated edge-to-opposing edge dimension of the initial molded part such that the target edge-to-opposing edge dimension is different from the pre-coated edge-to-opposing edge dimension, the target edge-to-opposing edge dimension being equal to a calculated value based on a model calculation that takes into account the coating thickness, the coating Young's modulus, and the initial molded part thickness.

22. The method of claim 21, wherein the modeling calculations comprise finite element analysis.

23. The method of claim 21 or 22, wherein the initial molded part comprises a substrate selected from the group consisting of: a laminated glass-based substrate, an ion-exchangeable glass-based substrate, a thermally strengthened glass-based substrate, and combinations thereof.

24. The method of claim 21 or 22, wherein the initial molded part comprises an ion-exchangeable glass-based substrate.

25. The method of claim 24, further comprising ion-exchange strengthening the ion-exchangeable glass-based substrate to strengthen the ion-exchangeable glass-based substrate prior to coating.

26. The method of claim 25, wherein the ion-exchange strengthening forms a surface compressive stress in an outer region of the ion-exchangeable glass-based substrate of 100MPa to 1100 MPa.

27. The method of claim 25, wherein the ion-exchange strengthening forms a surface compressive stress in an outer region of the ion-exchangeable glass-based substrate of 600MPa to 1100 MPa.

28. The method of any of claims 25-27, wherein modeling further comprises calculating a change in target dimension from edge to opposite edge due to ion exchange strengthening of the ion-exchangeable glass-based substrate.

29. The method of any of claims 21-28, wherein the coating imparts a compressive stress of 100MPa to 950 MPa.

30. The method of any of claims 21-29, wherein the coating has a thickness of 5 nanometers to 5 micrometers.

31. The method of any of claims 21-29, wherein the coating has a thickness of 10 nanometers to 2 micrometers.

32. A method of modeling dimensional changes of an initially glass-material-based component due to stresses imparted by a coating on the initially glass-based component that cause the formed component to bend, the method comprising:

generating a model that combines the coating thickness, the coating Young's modulus, the thickness of the glass-based material, and the Young's modulus of the glass-based material;

performing finite element analysis using the model, wherein performing the finite element analysis includes determining a dimension from an edge to an opposite edge prior to coating, the initial glass-based component including a shape prior to coating including a planar central portion and a peripheral portion bordering at least a portion of the planar central portion and extending outwardly from a plane of the planar central portion, the peripheral portion including a peripheral edge; and

a quantitative change in the pre-coated edge-to-opposing edge dimension of the initial glass-based component is determined based on the model as a result of the compressive stress imparted by the coating that results in the target edge-to-opposing edge dimension.

33. The method of claim 32, wherein modeling further comprises calculating a change in the pre-coated edge-to-opposing edge dimension due to ion exchange strengthening of the pre-coated edge-to-opposing edge dimension.

Technical Field

Embodiments of the present disclosure generally relate to methods of making coated glass-based components (e.g., glass-based covers).

Background

Glass-based articles, in particular, strengthened glass-based articles, are widely used in electronic devices, as covers or windows for portable or mobile electronic communication and entertainment devices (e.g., cell phones, smart phones, tablets, video players, Information Terminal (IT) devices, laptops, navigation systems, and the like), and in other applications, such as buildings (e.g., windows, shower panels, countertops, and the like), transportation (e.g., vehicles, trains, aircraft, seagoing, and the like), appliances, or any application that would benefit from superior shatter resistance but is also a thin and lightweight article. Strengthened glass-based articles (e.g., chemically strengthened glass-based articles), such as covers for cell phones, wearable items (e.g., watches), and other electronic devices, can be non-planar in shape and geometry (e.g., "three-dimensional" or "3D" and "2.5-dimensional"), containing some shapes that protrude from the surface, such asCurved cell phone cover glass andan edge cover glass. Such 2.5D and 3D shaped glasses present significant challenges to the shaping and reliability of cover glass based components.

Fig. 1 shows a representative, non-limiting shape for a 3D glass-based cover (also referred to in the art as a 3D cover glass), which may be used for electronic devices such as phones, televisions, flat panels, or monitors, etc. As shown in this figure, the 3D glass-based article is in the form of a cover 100, which includes: a planar central portion 101, a peripheral portion 102, and a peripheral edge 103. The planar central portion 101 is flat or nearly flat. The peripheral portion 102 extends out of the plane of the planar central portion 101 to provide the glass cover with an overall three-dimensional shape as opposed to a two-dimensional shape. Although as shown in fig. 1, the perimeter portion 102 completely surrounds the central portion 101, in some embodiments, the perimeter portion may extend only around a portion of the central portion (i.e., less than the entire perimeter), e.g., for a glass cover having a rectangular shape, less than all four sides of the glass cover may include the perimeter portion, e.g., two sides may have the perimeter portion and the other two sides may be flat or substantially flat. The perimeter edge 103 defines a dimension D1 from edge to opposite edge and a dimension D2 from edge to opposite edge. Similarly, to be three-dimensional, for a glass cover in the form of a dish or tray, it may have a portion (including only some or all) of its flat or near-flat central portion transition to a peripheral portion extending from the plane of the flat or near-flat central portion.

It is apparent that the shape of the 3D glass cover may vary widely depending on the desires of the designer of the device in which the 3D glass cover is used. Thus, the 3D glass cover can have various overall shapes, and can include central and peripheral portions of various sizes and shapes, and various configurations of transitions between the central and peripheral portions can be employed. Commonly assigned U.S. patent application No. 13/774,238 entitled "Cover Glass Article," filed 2013, 2, and 22, which is published as U.S. patent application publication No. 2013/0323444, provides various representative dimensions for a 3D Glass Cover, and also describes typical applications for the Cover, the entire contents of which are incorporated herein by reference.

The lateral dimension (thickness) of the peripheral edge 103 corresponds to the thickness of the glass-based sheet from which the glass-based covering is made, which is typically less than 1mm, for example: 0.8 millimeters or less, 0.7mm or less, 0.6mm or less, 0.5mm or less, 0.4mm or less, 0.3mm or less, 0.2mm or less, 0.1mm or less, 75 micrometers (microns or μm) or less, 50 micrometers or less, down to 10 micrometers. If functional coatings (e.g., scratch resistant or anti-reflective coatings) are applied to 2.5D and 3D glass parts based on shapes, the residual stress of the functional coating can cause the shape to bend, resulting in the part not meeting the specified dimensional tolerances. And this effect is greater as the glass becomes thinner.

Accordingly, it would be desirable to provide a method of manufacturing glass-based components with coatings that have mechanical and optical properties, and that apply coatings that maintain 2.5D and 3D component shapes within dimensional tolerances. In addition, it would be desirable to provide a method of manufacturing chemically strengthened (e.g., ion exchanged) glass-based articles having coatings with mechanical and optical properties and maintaining 2.5D and 3D part shapes within dimensional tolerances after the coatings are applied.

Disclosure of Invention

A first aspect of the present disclosure pertains to making a glass-based article having a coating and a target shape, the target shape comprising: a planar central portion and a perimeter portion bordering at least a portion of the planar central portion and extending outwardly from a plane of the planar central portion, the perimeter portion having a perimeter edge and a target dimension from the edge to an opposite edge. The method comprises the following steps: a glass-based component (also referred to as a glass-based article or a glass-based substrate) is formed to provide an initially-formed component having an initial three-dimensional shape that differs from a target shape at least with respect to an edge-to-opposite edge target dimension. Applying a coating to the initially formed part to form a glass-based article having a coating that imparts a stress to the initially molded part that results in a calculated bend-induced change to the initial shape.

Another aspect of the present disclosure pertains to a method of making a glass-based article comprising: forming an initial molded part with a mold having a molding surface, the initial molded part having a pre-coated three-dimensional shape including a planar central portion and a peripheral portion bordering at least a portion of the planar central portion and extending outwardly from the plane of the planar central portion, thereby providing the initial molded part with three-dimensional characteristics, the peripheral portion having a peripheral edge and pre-coated edge-to-opposing edge dimensions; and coating the initial molded part with a coating that imparts a stress on the initial molded part that causes the initial molded part to bend and changes a pre-coated edge-to-opposing edge dimension of the initial molded part to provide an edge-to-opposing edge target dimension that is different than the pre-coated edge-to-opposing edge dimension, the edge-to-opposing edge target dimension being equal to a calculated value based on model calculations that take into account the coating thickness, the coating young's modulus, and the initial molded part thickness to form the glass-based article.

Another aspect of the present disclosure pertains to a method of modeling dimensional changes of an initial glass-based component due to stresses imparted on the component by a coating on the component that cause the component to bend, the method comprising: generating a model on a computer, the model incorporating the coating thickness, the coating Young's modulus, the thickness of the glass-based material, and the Young's modulus of the glass-based material; performing finite element analysis on the computer using the model, wherein performing the finite element analysis comprises: determining a part formed from an initial base material having a pre-coating shape comprising: a planar central portion and a perimeter portion bordering at least a portion of the planar central portion and extending outwardly from the plane of the planar central portion, the perimeter portion having a perimeter edge and a dimension from the edge to the opposite edge prior to coating; and determining on the computer, based on the model, a quantitative change in a pre-coated edge-to-opposing edge dimension of the initially glass-based formed part as a result of the compressive stress imparted by the coating that results in the target edge-to-opposing edge dimension.

Drawings

FIG. 1 is a perspective view of a representative 3D glass cover;

FIG. 2 shows a strengthened glass-based substrate having a coating on one side, according to some embodiments;

FIG. 3 shows a measured strain to failure versus thickness plot for a glass-based substrate comprising a coating;

FIG. 4 is a model-based plot showing the critical strain percentage versus normalized flaw size;

FIG. 5 is a model-based plot showing critical strain% versus normalized flaw size;

FIG. 6 shows predicted substrate curvature versus substrate thickness for parts having various coating thicknesses;

FIG. 7A shows the shape of the covering member measured before ion exchange;

FIG. 7B shows the cover member shape measured after ion exchange;

FIG. 8 shows a modeled finite element analysis diagram illustrating the bending of the disk shaped member after ion exchange;

FIG. 9 shows a measurement of the change in shape of a bend-compensating part produced by the bend correction die; and

fig. 10 shows a schematic cross-sectional view of a representative mold for producing a 3D glass cover.

Detailed Description

Before describing several exemplary embodiments, it is to be understood that the present disclosure is not limited to the details of construction or process steps set forth. The disclosure provided herein is capable of other embodiments and of being practiced or being carried out in various ways.

Reference throughout this specification to "one embodiment," "certain embodiments," "some embodiments," "various embodiments," "one or more embodiments," or "an embodiment" means that a particular feature, structure, material, or characteristic described in connection with the embodiment is included in at least one embodiment of the present disclosure. Thus, the appearances of the phrases such as "in one or more embodiments," "in certain embodiments," "in various embodiments," "in one embodiment," "in some embodiments," or "in an embodiment" in various places throughout this specification are not necessarily referring to the same embodiment. Furthermore, the particular features, structures, materials, or characteristics described in connection with one embodiment may be combined in any suitable manner in one or more other embodiments. The various glass-based articles and methods described herein can be selected from the group consisting of: glass-based substrates for architectural use, vehicle glazing, glass-based substrates for vehicle interiors, glass-based substrates for appliances, glass-based substrates for handheld devices (e.g., components for screen coverings), and glass-based substrates for wearable devices.

One or more embodiments of the present disclosure provide a glass-based article that includes a glass-based substrate having an initial shape and a coating on the glass-based substrate. In one or more embodiments, the coating imparts a stress to the initially formed component that results in a calculated bend-induced change in the initial shape. The coating may comprise a multi-layer coating. The glass-based components or substrates may be flat, or they may be bent in one or more directions (e.g., x, y, and/or z planes) to provide a three-dimensional substrate or component. The glass-based substrate or component may be cold-formed. In one or more embodiments, the substrate or component can be curved in at least one direction (e.g., x, y, and/or z plane). In one or more embodiments, the glass-based substrate or component can have 2.5 dimensions, e.g., with beveled edges.

In accordance with one or more embodiments, a coated glass-based article is provided. In one or more embodiments, the glass-based article includes a coating applied for functions such as: scratch resistance, damage resistance (e.g., sharp contact induced cracking), antimicrobial properties, anti-reflective properties, capacitive touch sensitivity, photochromic coatings, or other optical properties. The coating may be applied by any suitable technique, for example, Chemical Vapor Deposition (CVD) (e.g., plasma enhanced CVD, low pressure CVD, atmospheric CVD, and plasma enhanced atmospheric CVD), Physical Vapor Deposition (PVD) (e.g., reactive or non-reactive sputtering or laser ablation), thermal or electron beam evaporation, and/or atomic layer deposition. The coating may also be applied by dipping, spraying, brushing, spin coating, and other suitable techniques.

Provided herein are methods of producing coated glass-based articles (e.g., covers for electronic devices) having a shape that closely corresponds to the shape specified by the article designer (target shape; in the case of shapes specified by CAD drawing, also referred to as "CAD shape" (CAD refers to computer aided design)). The 2.5D and 3D glass-based articles tend to bend after the application of a coating that imparts stress to the surface of the coated part. Bending occurs as the coating imparts stress to the glass-based article. This results in an increase or decrease in the size of the glass, depending on whether the coating imparts a tensile or compressive stress to the surface of the glass-based article, and depending on the side of the glass-based article to which the coating is applied. To determine whether the size of the glass-based article (in, for example, one or both of the x-plane or the y-plane) is increasing or decreasing, measurements are taken of the size of the glass-based article before and after coating.

Shape deviations due to coating-induced bending are undesirable because consumer specifications for dimensional tolerances can be ± 100 microns or less. To compensate for such coating-induced bending, methods are provided to calculate the degree of dimensional change in the glass-based component in advance, thereby providing the calculated bending-induced change to the initial shape and size.

Since the coating-induced bending depends on the details of the overall shape of the glass-based article and the details of the shape and thickness of the edges of the article, the correction value is obtained by converting the coating-induced bending problem to a thermal diffusion problem, thereby enabling the use of commercial software (e.g., sold by ANSYS ltd., 15317 cannon steburg technical dao 275, pa)Software (ANSYS inc.,275Technology Drive, Canonsburg, PA15317, USA) that employs finite element and graphical display techniques to solve the coating-induced bowing problem. Further, the target shape (specifically, the target shape in CAD format) may be input into such commercial software. In practice, using the techniques disclosed herein, mold contour correction may be provided for molds used to form glass-based components, which may be developed without the need for iterative changes to the physical mold.

In some embodiments, 3D glass-based articles are manufactured from 2D glass sheets using a thermal reforming process, such as described in U.S. patent application publication nos. 2010/0000259 and 2012/0297828, which are incorporated herein by reference in their entirety. In some embodiments, the 2D glass sheet is manufactured by a fusion process, although 2D glass sheets manufactured by other processes, such as float, down, up, or roll processes, may also be used.

Thus, the initially formed glass-based component may be shaped into a 3D shaped glass-based article by a thermoforming process (e.g., by molding). This initially formed part may then be coated. In one or more embodiments, prior to coating, the component may be chemically strengthened by ion exchange, which may induce ion exchange bending. Thus, in embodiments where the component is ion exchanged, both the ion exchange induced bending and the coating induced bending are determined/calculated prior to manufacture to determine the magnitude of the dimensional change to the initially formed component. In one or more embodiments, a method comprises: forming a glass-based article in a mold having a molding surface, and the molding surface is designed and dimensioned to compensate for the calculated bend-induced variation of the initial shape such that the glass-based article having the coating has a target shape and target edge-to-opposing edge dimensions. In one or more embodiments, the initially formed part may have a three-dimensional characteristic or curvature, and a coating is applied that imparts stress to the coated part having the initial shape to remove the curvature from the initially formed part to provide a coated final part having a flat shape.

Referring now to fig. 2, embodiments of the present disclosure pertain to a coated glass-based article 200, such as a glass-based covering, that includes a glass-based substrate 210, the glass-based substrate 210 having a first surface 215 (having a first coating 220 thereon providing a first interface 225 between the first coating 220 and the glass-based substrate 210) and a second surface 325 opposite the first surface 215. First coating 220 has a first coating thickness t extending from first coating surface 230 to first surface 215_c. The glass-based substrate 210 has a substrate thickness t extending from the first surface 215 to the second surface 235_s. The substrate thickness ranges from 0.01 millimeters (mm) to 3mm, for example: 0.01mm to 2.75mm, 0.01mm to 2.5mm, 0.01mm to 2.25mm, 0.01mm to 2.0mm, 0.01mm to 1.75mm, 0.01mm to 1.5mm, 0.01mm to 1.25mm, 0.01mm to 1.0mm, 0.01mm to 0.75mm, 0.01mm to 0.5mm, 0.025mm to 3.0mm, 0.05mm to 3.0mm, 0.075mm to 3.0mm, 0.1mm to 3.0mm, 0.2mm to 3.0mm, 0.3mm to 3.0mm, 0.05mm to 2.5mm, 0.075mm to 2.0mm, 0.1mm to 1.75mm, 0.1mm to 1.5mm, 0.1mm to 1.25mm, 0.1mm to 1.5mm, 0.1mm to 1.0mm, 0.1mm to 1.0.0 mm, 0.1mm to 1.5mm, 0.0.0 mm, 0.1mm to 1.0mm, 0.8mm, 0.0 mm, 0.1mm to 1mm, 0.0 mm, 0.0.0 mm, 0 to 1.0mm, 0mm, 0.0 to 1mm, 0mm, or 1 mm. The first coating 220 imparts a stress on the glass-based substrate 210. The first coating 220, which may be on the first surface 215 or the second surface 235 of the substrate 210, has a thickness of about 80 nanometers to about 80 nanometersCoating thickness t of 10 microns_c. In some embodiments, the glass-based article is not strengthened. In fig. 2, the glass-based substrate 210 has a compressive stress region 240 extending from the first surface 215. The compressive stress region has a surface Compressive Stress (CS) at a surface of the glass-based article of about 750MPa up to about 1200MPa and extends to a depth of compression (DOC) at which point the stress transitions from compressive to tensile. In one or more embodiments, the first coating layer 220 imparts a compressive stress to the substrate 210. In other embodiments, the first coating layer 220 imparts a tensile stress to the substrate 210. Depending on the desired final part shape, a tensile stress-inducing or compressive stress-inducing coating may be selected and applied to at least one of the first surface 215 and the second surface 235, which imparts stress to the substrate 210, changing the initial shape of the part, thereby causing a calculated bend-induced change in the part shape and edge-to-opposite edge dimensions of the initially formed part.

FIG. 3 shows a graph of measured strain to failure versus thickness for a hard, brittle coating applied to chemically strengthened glass. FIG. 3 shows the importance of the stress state of the coating and the thickness of the coating to increase the robustness of the coating and of the underlying substrate, measured as% strain to failure. Overall, as the% strain to failure increases, the object becomes stronger and more resistant to damage. The round data points represent the failure strain of the coating, while the square data points represent the failure strain of the substrate itself. All samples had the same underlying substrate composition, thickness and stress profile. For sample D, the coating and substrate failure strains were substantially the same, about 70%. Samples a and B both had a 460nm thick coating, where both coatings had young's modulus (E) of about 188 GPa. Samples C and D had a 1160nm thick coating, wherein the coating had a young's modulus (E) of about 229 GPa. The coating stress (σ) of coatings C, B, A and D was 479MPa (tensile), 147MPa (tensile), 90MPa (tensile) and-960 MPa (compressive), respectively. Comparing coatings of the same thickness and young's modulus shows that more tensile (less tensile) stresses result in an increase in the strain to failure of both the coating and the substrate. For example, coatings a and B have the same thickness and young's modulus, but coating a (with less tensile stress) has increased strain to failure. Similarly, coatings C and D have the same thickness and young's modulus, but coating D (with less tensile stress) has increased strain to failure. Furthermore, as can be seen from fig. 3, a thinner coating results in an increase in strain to failure, particularly for the underlying substrate. For example, comparing samples a and B (each having a thickness of 460 nm) with sample C (having a thickness of 1160 nm), it is seen that the strain to failure of both the coating and the underlying substrate increases in the samples with the thinner coating. Similarly, comparing samples a and B (each having a thickness of 460 nm) with sample D (having a thickness of 1160 nm), it is seen that the strain to failure of the underlying substrate increases in the samples with the thinner coating. Thus, in general, thinner, less stretched substrates tend to produce products with more robust coatings and underlying substrates.

Fig. 4 shows the results of the model for critical strain plotted against normalized flaw size. Similar to the strain to failure, the critical strain is a measure of the robustness of the substrate and coating. In general, the higher the critical strain, the more robust the object (substrate, coating or coated substrate) will be (failure, such as cracking, is less likely to occur, as this makes flaws more difficult to propagate). Fig. 4 shows the critical strain of the underlying glass substrate itself when coated with a 1.1 micron thick coating. The solid line represents a coating with a tensile stress of 0.48GPa and the dashed line represents a coating with a compressive stress of 1.0 GPa. Similar to fig. 3, fig. 4 shows that making the coating less stretchable provides a more robust coated substrate.

Further modeling work was performed with a 2.0 μm thick coating as shown in fig. 5. Similar improvements were found for coating and substrate robustness as shown in both figures 3 and 4 (critical strain is measured here). More specifically, all coatings had the same 2 micron thickness, were the same material (AlON), and were all modeled on substrates with the same composition, thickness, and stress distribution. Similar to fig. 3 and 4, fig. 5 shows that for a given coating thickness, the sample becomes stronger as the coating stress becomes less tensile. And figure 5 demonstrates this relationship across all standardized flaw sizes. Furthermore, comparing fig. 4 and 5, it is again seen that thinner coatings have greater improvement in sample firmness. Specifically, fig. 4 shows that for a normalized flaw size of 4, a thinner (1.1 micron) coating with a 1.0GPa coating compression has a critical strain of about 0.95%. On the other hand, fig. 5 shows that for a normalized flaw size of 4, the thicker (2 micron) coatings with 1.0GPa compressive stress (triangular data points) have a critical strain of less than 0.8%.

Thus, as can be seen from fig. 3-5, proper selection of the coating (for its thickness and its stress level) can have a beneficial effect on the robustness of the coated substrate. Therefore, more compressive coatings are desired.

Furthermore, it is believed that by moderately increasing the glass compressive stress, a progressive improvement in drop performance can be obtained. Thus, it follows that an increase in AlON coating compression (as well as compression of other types of coatings) can improve sharp break contact resistance during a drop event, thereby improving drop performance. It is expected that coating compression improves the crack initiation strain of the coating and the flexural strength of the glass.

Coating compression or tension can be achieved by varying coating deposition parameters or by mechanical means. For example, in one or more embodiments, a Coefficient of Thermal Expansion (CTE) difference or temperature difference between the coating and the glass-based component may be used to increase or decrease the coating compression or tension. For example, if the CTE of the coating is lower than that of the underlying glass-based component, the coating may exert a compressive force on the underlying component. In one or more embodiments, high energy coating deposition can be used to provide a dense, dense backing coating that can result in compressive stresses on the underlying glass-based component. The coating density can be controlled by varying the coating deposition parameters.

However, compressive coatings impart compressive forces on glass-based substrates that can bend the part and cause part dimensional changes from the originally formed dimensions, and it is presently believed that high coating stress levels are undesirable due to part bending. However, during forming, bending occurs naturally due to the snap-back thermal gradient effect and chemical strengthening of the asymmetric three-dimensional machined or molded forming part. Fast spring back and thermal gradient operation can be controlled by process regulation and control. But the bending due to ion exchange is due to stress rebalancing, which causes deformation due to the asymmetric shape through the thickness. Thus, ion exchange induced bending of the molded formed part may be accounted for by compensating for the mold shape so that the part returns to the final desired shape after the ion exchange process, as described in U.S. patent No. 9,292,634, which is incorporated herein by reference in its entirety. Because the coating deposition-induced bowing is due to compressive or tensile stresses in the coating that cause rebalancing, the final shape of the coated glass-based article (e.g., glass-based covering) can be predicted by modeling. The bend-compensating die can be designed to achieve the desired shape of the part after both coating application and ion exchange. A similar process can be performed for molding of non-three-dimensional parts to produce a shape that becomes flat after the coating is applied. However, applying the method to a three-dimensional part does not add extra steps to the process.

For a flat plate with a thin coating, the stegnoni equation can be used to estimate the part bending. While the present disclosure is primarily directed to 3D applications, it may also be applicable to 2.5D parts (e.g., parts with beveled edges) and flat substrates. Furthermore, studying the flat plate curvature of a two-dimensional plate may provide an understanding of the curvature that may be created in the formed three-dimensional part. The results of the strornia equation are given in fig. 6, and it can be seen that the curvature (K) depends on both coating thickness and stress. The strony equation is shown below in equation 1:

where K denotes curvature, σ (f) denotes stress imparted to the glass-based molded part by the coating, h_fIndicating coatingThickness, v_sRepresenting the Poisson's ratio of the glass-based moulded part, E_sDenotes the Young's modulus of the glass-based molded part, and h_sIndicating the thickness of the glass-based molded part. Based on the stronih equation, such that Es is 65GPa, the predicted substrate curvature (K) for glass-based components of different coating thicknesses and coating stresses can be determined.

As can be seen from equation (1) and fig. 6, the derivative of the curvature (K) with respect to the square of the substrate thickness (h) increases. As covers for electronic devices (e.g., cell phones) become thinner, the coating stress state becomes more affected, and the curvature due to the coating increases. The curvature also increases linearly with coating stress (e.g., for a given substrate thickness, the curvature (K) increases as the stress increases from 500MPa compressive stress to 2GPa compressive stress). This again shows that the more compressive stress (less tensile stress) in the coating is advantageous for the robustness of the coated substrate. However, again, as the coating compression increases, the bending of the substrate increases. Thus, to obtain the benefit of increased coating compression and still maintain the desired part shape, the curvature of the coating is compensated for in accordance with the present disclosure.

Fig. 7A and 7B demonstrate experimental measurements of the bend produced by ion exchange of components that were not bend compensated. Fig. 7A shows the shape before ion exchange and fig. 7B shows the deviation (in millimeters) from the CAD shape dimensions after ion exchange. More specifically, the numbers in each of these figures represent the distance of the position of the substrate surface relative to a given reference plane. Thus, in the center of FIG. 7A, the substrate surface is seen to be offset by 0.04mm from the reference plane. On the other hand, it can be seen in fig. 7B that the same central portion of the substrate is deviated by 0.15mm from the reference plane. Comparing these values for the central portion of fig. 7A with the same central portion of fig. 7B, it is seen that ion exchange results in an additional 0.11mm deviation (e.g., 0.15-0.4 ═ 0.11). Thus, after ion exchange, the part shape may vary up to about 0.1mm or more, particularly for portions where flatness is desired (e.g., the main portion of the display screen, as opposed to the perimeter edges which are already curved). Such shape variations can cause the components to fall outside of tight geometric tolerances. This warping from ion exchange is a complement to what is caused by the stress of the coating itself. However, these curvatures can all be compensated for by adjusting the shape of the substrate (relative to the target shape) prior to ion exchange and coating.

Fig. 8 shows a simulation of the ion exchange process by thermal diffusion contrast, which is based on the results of finite element analysis of the bending of the disk-shaped part after ion exchange. In fig. 8, the bending size is not proportional to the component dimensions, and the dimensions provided are microns. With knowledge derived from such modeling, the mold can be bend compensated to produce parts that meet tight tolerances. That is, the ion exchange induced bowing can be predicted with considerable accuracy, so that the bowing compensation (and coating induced bowing) can be compensated for to produce a desired target shape in the component.

An example of an ion exchange bend compensation component is shown in fig. 9, where the dimensions are in millimeters. Likewise, similar to fig. 7A and 7B, the number at each position of the component represents the deviation of that position from the reference plane. However, in fig. 9, the measurements before and after ion exchange are shown on the same figure, simply as the difference between the two. Thus, for the center of the part in fig. 9, the shape change is 0, unlike the 0.11mm shape change in the example of fig. 7A and B. That is, the compensated part (fig. 9) is much flatter, i.e., less out-of-plane distortion, than the uncompensated part (fig. 7B). Similar die corrections can be applied directly to shape changes due to coating residual stresses. Coating deposition induced curvature (as shown in fig. 6) and ion exchange induced displacement as shown in fig. 7A and 7B can be corrected using the methods described herein to produce a component that falls within the target geometric tolerances, similarly to the process used to produce the component shown in fig. 9.

Herein, the present disclosure provides methods of improving the performance of coatings and substrates of composite systems. Coating viability is a property of device functionality and user experience, while component or cover viability is a property of preventing cover glass system level failures.

Fig. 10 shows a schematic cross-sectional view of a representative mold suitable for use in a thermoforming process. The mold 300 includes a mold body 302 having a top surface 306 and a cavity 304. The cavity is open at the top surface 306 and includes a molding (shaping) surface 308 at its bottom. The molding surface 308 has a surface profile according to the present disclosure that is corrected to complement the coating-induced curvature and/or the ion-exchange induced curvature, which results in a calculated curvature-induced change in the initial shape of the part formed in the mold 300. It will be appreciated that the profile of the molding surface 308 will vary from that shown in fig. 10 depending on the specifications of the 3D glass cover to be manufactured.

As shown in fig. 10, the mold body 302 may include one or more apertures and/or holes 310 (hereinafter "pores") extending from a bottom surface 315 of the mold body to the molding surface. The apertures 310 are arranged to provide communication between the exterior of the mold and the molding surface. In one example, the aperture is a vacuum aperture. That is, the apertures may be connected to a vacuum pump (not shown) or other device for providing a vacuum to the cavity 304 through the molding surface 308.

Fig. 10 also shows a flat glass-based substrate 318 having a portion 320 located over the cavity 304. Briefly, in forming a 3D glass cover using a mold of the type shown in FIG. 10, plate 318 is heated so that it sags into cavity 304 while a vacuum is applied to conform the shape of the softened glass to the shape that has been machined into molding surface 308. To withstand the temperatures associated with this process, the mold 300 may be made of a heat resistant material. For example, the mold may be made of high temperature steel or cast iron. To extend the life of the mold, the molding surface may be coated with a high temperature material (e.g., a chrome coating) that reduces the interaction between the mold and the glass that makes up the glass cover.

Various embodiments of the present disclosure will be described in detail below. In a first embodiment, a method of making a glass-based article having a coating and a target shape including a planar central portion and a peripheral portion bordering at least a portion of the planar central portion and extending outwardly from the plane of the planar central portion is provided. The perimeter portion has a perimeter edge and a target dimension edge to opposite edge. In a1 st embodiment, a method comprises: forming a glass-based part to provide an initially-formed part having an initial three-dimensional shape that is different from a target shape at least for a target dimension from edge to opposite edge; and applying a coating to the initially formed part to form a glass-based article having a coating that imparts a stress to the initially formed part that results in a calculated bend-induced change in the initial shape. In embodiment 2, the initially formed part of embodiment 1 has a three-dimensional shape. In embodiment 3, the target shape of embodiment 2 is flat.

In a 4 th embodiment, a 2 nd embodiment includes: forming the glass-based article includes forming the glass-based article in a mold having a molding surface, and wherein the molding surface is designed and dimensioned to compensate for the calculated bend-induced variation of the initial shape such that the glass-based article having the coating has a target shape and target edge-to-opposing edge dimensions. In the 5 th embodiment, the target shape of the 4 th embodiment is three-dimensional.

In the 6 th embodiment, the coating imparts a compressive stress to the formed component of any of the 1 st to 5 th embodiments. In embodiment 7, the coating imparts a tensile stress to the formed component of any of embodiments 1 through 5. In the 8 th embodiment, the calculated bending-induced change of the initial shape is determined by the modeling of any one of the 1 st to 7 th embodiments. In an 9 th embodiment, the modeling of the 8 th embodiment includes finite element analysis.

In a 10 th embodiment, in the method of any one of embodiments 1 through 9, the initially formed part comprises a substrate selected from the group consisting of: a laminated glass-based substrate, an ion-exchangeable glass-based substrate, a thermally strengthened glass-based substrate, and combinations thereof. In an 11 th embodiment, the initially-formed component of any one of embodiments 1-9 includes an ion-exchangeable glass-based substrate.

In an embodiment 12, the glass-based substrate of any one of embodiments 1 through 11 comprises an ion-exchangeable alkali aluminosilicate glass composition. In a 13 th embodiment, the glass-based article of any one of embodiments 1 through 11 includes an ion-exchangeable alkali aluminoborosilicate glass composition.

In a 14 th embodiment, the method of embodiment 11 further comprises ion-exchange strengthening the ion-exchangeable glass-based substrate, thereby strengthening the ion-exchangeable glass-based substrate prior to coating. In a15 th embodiment, the ion-exchange strengthening of the 14 th embodiment forms a CS of 100MPa to 1100MPa in the outer region of the ion-exchangeable glass-based substrate.

In a 16 th embodiment, the ion-exchange strengthening of the 14 th embodiment forms a CS of 600MPa to 1100MPa in the outer region of the ion-exchangeable glass-based substrate. In an 17 th embodiment, the modeling of any of the 14 th to 16 th embodiments further comprises calculating a change in the initial shape due to ion exchange strengthening of the ion-exchangeable glass-based substrate.

In an 18 th embodiment, the coating of any of embodiments 1 through 6 and 8 through 17 imparts a compressive stress of 100MPa to 950MPa, more specifically 400 and 950 MPa. In a 19 th embodiment, the coating of any one of embodiments 1 to 18 has a thickness of 5 nanometers to 5 micrometers.

In a 20 th embodiment, the coating of any one of embodiments 1-19 has a thickness of 10 nanometers to 2 micrometers.

A 21 st embodiment pertains to a method of making a glass-based article, comprising: forming an initial molded part with a mold having a molding surface, the initial molded part having a pre-coated three-dimensional shape including a planar central portion and a peripheral portion bordering at least a portion of the planar central portion and extending outwardly from the plane of the planar central portion, thereby providing the initial molded part with three-dimensional characteristics, the peripheral portion having a peripheral edge and pre-coated edge-to-opposing edge dimensions; and coating the initial molded part with a coating that imparts a stress on the initial molded part that causes the initial molded part to bend and changes a pre-coated edge-to-opposing edge dimension of the initial molded part to provide an edge-to-opposing edge target dimension that is different than the pre-coated edge-to-opposing edge dimension, the edge-to-opposing edge target dimension being equal to a calculated value based on model calculations that take into account the coating thickness, the coating young's modulus, and the initial molded part thickness to form the glass-based article. In a 22 nd embodiment, the modeling calculations of the 21 st embodiment include finite element analysis.

In an 23 rd embodiment, the initially molded part of any one of the 21 st and 22 nd embodiments comprises a substrate selected from the group consisting of: a laminated glass-based substrate, an ion-exchangeable glass-based substrate, a thermally strengthened glass-based substrate, and combinations thereof. In a 24 th embodiment, the initial molded part of any of the 21 st and 22 nd embodiments comprises an ion-exchangeable glass-based substrate. In a 25 th embodiment, the 24 th embodiment further comprises ion-exchange strengthening the ion-exchangeable glass-based substrate to strengthen the ion-exchangeable glass-based substrate prior to coating. In a 26 th embodiment, the ion-exchange strengthening of the 25 th embodiment forms a CS of 100MPa to 1100MPa in an outer region of the ion-exchangeable glass-based substrate. In an 27 th embodiment, the ion-exchange strengthening of the 25 th embodiment forms a CS of 600MPa to 1100MPa in an outer region of the ion-exchangeable glass-based substrate.

In an 28 th embodiment, the modeling of any of the 25 th through 27 th embodiments further comprises calculating a change in the target dimension from the edge to the opposite edge before coating due to ion exchange strengthening of the ion-exchangeable glass-based substrate.

In an 29 th embodiment, the coating of any one of embodiments 21 to 28 imparts a compressive stress of 100MPa to 950 MPa. In a 30 th embodiment, the coating of any one of the 21 st to 29 th embodiments has a thickness of 5 nanometers to 5 micrometers. In an embodiment 31, the coating of any of embodiments 21-30 has a thickness of 10 nanometers to 2 micrometers.

A 32 nd embodiment pertains to a method of modeling dimensional changes of an initial glass-based component due to stresses imparted by a coating on the initial glass-based component that cause the formed component to bend. The method of the 32 nd embodiment comprises: generating a model on a computer, the model incorporating the coating thickness, the coating Young's modulus, the thickness of the glass-based component, and the Young's modulus of the glass-based component; performing finite element analysis on the computer using the model, wherein performing the finite element analysis includes determining a pre-coated edge-to-opposing edge dimension of the glass-based component, and wherein the initial glass-based component has a pre-coated shape comprising: a planar central portion and a perimeter portion bordering at least a portion of the planar central portion and extending outwardly from a plane of the planar central portion, the perimeter portion having a perimeter edge; and determining on a computer, based on the model, a quantitative change in a pre-coated edge-to-opposing edge dimension of the initial glass-based component due to the stress imparted by the coating, which results in an edge-to-opposing edge target dimension.

In an 33 rd embodiment, the modeling of the 32 nd embodiment further includes calculating on a computer the edge-to-opposing-edge dimensional change before coating due to ion-exchange strengthening of the initial glass-based material molded part.

As used herein, the terms "glass-based article," glass-based object, "" glass-based substrate, "" glass-based component"and" glass-based covering "are used in their broadest sense to include any object made in whole or in part of glass, including glass, glass-ceramic, and sapphire₂O-Al₂O₃-SiO₂System (i.e., L AS system) glass-ceramic, MgO-Al₂O₃-SiO₂System (i.e., MAS system) glass-ceramic, ZnO × Al₂O₃×nSiO₂(i.e., ZAS system) and/or a glass-ceramic comprising a primary crystalline phase having β -quartz solid solution, β -spodumene, cordierite, and lithium disilicate₂SO₄Strengthening in molten salt, 2L i can occur⁺Is coated with Mg²⁺And (4) exchanging. Glass-based objects include laminates of glass and non-glass materials, laminates of glass and crystalline materials, and glass-ceramics (including amorphous and crystalline phases). All compositions are expressed as mole percent (mol%) unless otherwise indicated. Glass-based substrates and components according to one or more embodiments may be selected from: soda lime glass, alkali aluminosilicate glass, alkali containing borosilicate glass, and alkali aluminoborosilicate glass. In one or more embodiments, the substrate or component is glass, and the glass can be strengthened, for example, thermally strengthened tempered glass or chemically strengthened glass (e.g., ion exchanged glass). In one or more embodiments, the strengthened glass-based substrate or component has a CS layer, with the CS in the chemically strengthened glass extending from the surface of the chemically strengthened glass to a compressive stress depth of compression (DOC) of 10 μm or more, and up to tens or even hundreds of microns in depth. In one or more embodiments, the glass-based substrate is a chemically strengthened glass-based substrate, for example,glass (available from corning, inc., new york, usa).

As used herein, the term "about" means that amounts, sizes, formulations, parameters, and other variables and characteristics are not and need not be exact, but may be approximate and/or larger or smaller as desired, reflecting tolerances, conversion factors, rounding off and measurement errors and the like, and other factors known to those of skill in the art. When the term "about" is used to describe a value or an endpoint of a range, it is to be understood that the disclosure includes the particular value or endpoint referenced. Whether or not the numerical values or range endpoints of the specification recite "about," the numerical values or range endpoints are intended to include two embodiments: one modified with "about" and one not. It will be further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint.

As used herein, the terms "substantially", "essentially" and variations thereof are intended to mean that the features described are equal or approximately the same as the numerical values or descriptions. For example, a "substantially planar" surface is intended to mean a planar or near-planar surface. Further, "substantially" is intended to mean that the two values are equal or approximately equal. In some embodiments, "substantially" may mean values within about 10% of each other, such as within about 5% of each other, or within about 2% of each other.

Thus, for example, a glass-based article that is "substantially free of MgO" is one in which MgO is not actively added or dosed to the glass-based article, but may be present in very small amounts as a contaminant.

Directional terminology used herein, such as upper, lower, left, right, front, rear, top, bottom, is for reference only to the accompanying drawings and is not intended to be absolute.

As used herein, the terms "the," "an," or "an" mean "at least one," and should not be limited to "only one," unless expressly stated to the contrary. Thus, for example, reference to "a component" includes embodiments having two or more such components, unless the context clearly indicates otherwise.

A variety of different processes may be employed to provide the glass-based substrate for forming the initial components and the cover. For example, exemplary methods of forming glass-based substrates include float glass processes and down-draw processes, such as fusion and slot draw, up-draw, and roll processes. Glass-based substrates made by the float glass process can be characterized as having a smooth surface and uniform thickness, and are manufactured by floating molten glass on a bed of molten metal (typically tin). In an exemplary process, molten glass is fed onto the surface of a bed of molten tin to form a floating glass ribbon. As the ribbon flows along the tin bath, the temperature is gradually reduced until the ribbon solidifies into a solid glass-based substrate, which can be lifted from the tin onto the rollers. Once out of the bath, the glass-based substrate may be further cooled and annealed to reduce internal stresses.

The downdraw process produces a glass-based substrate having a uniform thickness that has a relatively pristine surface. Because the average flexural strength of the glass-based substrate is controlled by the amount and size of the surface flaws, the pristine surface that is minimally contacted has a higher initial strength. When such high strength glass-based substrates are subsequently further strengthened (e.g., chemically strengthened), the resulting strength may be higher than that of a glass-based substrate whose surface has been lapped and polished. The drawn glass-based substrate may be drawn to a thickness of less than about 2mm, for example: 1.75mm, 1.5mm1.25mm, 1.1mm, 1.0mm, 0.9mm, 0.8mm, 0.7mm, 0.6mm, 0.5mm, 0.4mm, 0.3mm, 0.2mm, 0.1mm, 0.075mm, 0.05mm, and any range or subrange therebetween. Furthermore, the substrate based on drawn glass has a very flat, smooth surface which can be used for end applications without costly grinding and polishing.

The fusion draw process uses, for example, a draw tank having a channel for receiving molten glass raw materials. The channel has weirs that open at the top of both sides of the channel along the length of the channel. As the channel is filled with molten material, the molten glass overflows the weir. Under the influence of gravity, the molten glass flows down from the outer surface of the draw tank as two flowing glass films. The outer surfaces of these drawn cans extend downwardly and inwardly so that they join at the edge below the drawn can. The two flowing glass films are joined at the edge to fuse and form a single flowing glass-based substrate. The fusion drawing method has the advantages that: because the two glass films overflowing the channel fuse together, neither outer surface of the resulting glass-based substrate is in contact with any component of the apparatus. Thus, the surface properties of the fusion drawn glass-based substrate are not affected by such contact.

The slot draw process is different from the fusion draw process. In the slot draw process, molten raw material glass is supplied to a draw tank. The bottom of the draw vessel has an open slot with a nozzle extending along the length of the slot. The molten glass flows through the slot/nozzle, down-draw as a continuous substrate, and into an annealing zone. In some embodiments, a composition for a glass-based substrate may be formulated with 0 to 2 mole% of at least one fining agent selected from the group consisting of: na (Na)₂SO₄、NaCl、NaF、NaBr、K₂SO₄KCl, KF, KBr and SnO₂。

Once formed, the glass-based substrate used to make the initial component can be strengthened to form a strengthened glass-based substrate, thereby providing a strengthened substrate coated with a brittle coating. It should be noted that the glass-ceramic substrate may also be strengthened in the same manner as the glass-based substrate. As used herein, the term "strengthened substrate" can refer to a glass-based substrate that is chemically strengthened by, for example, ion-exchanging larger ions for smaller ions in the surface of the glass-based substrate. However, the strengthened glass-based substrate may be formed using strengthening methods known in the art, such as thermal tempering or thermal strengthening. In some embodiments, a combination of chemical and thermal strengthening processes may be used to strengthen the substrate.

Examples of glasses that may be used to make substrates and components may include alkaline aluminum siliconAn acid salt glass composition or an alkali aluminoborosilicate glass composition, although other glass compositions are also contemplated. Such glass compositions can be characterized as being ion-exchangeable. As used herein, "ion-exchangeable" means that the substrate comprises a composition that enables the exchange of larger or smaller sized homovalent cations with cations located at or near the surface of the substrate. An exemplary glass composition comprises SiO₂、B₂O₃And Na₂O, wherein (SiO)₂+B₂O₃) Not less than 66 mol% and Na₂O is more than or equal to 9 mol percent. In some embodiments, suitable glass compositions further comprise K₂O, MgO and CaO. In some embodiments, a glass composition for a substrate may comprise: 61-75 mol% SiO₂(ii) a 7-15 mol% Al₂O₃(ii) a 0-12 mol% of B₂O₃(ii) a 9-21 mol% of Na₂O; 0-4 mol% of K₂O; 0-7 mol% MgO; and 0-3 mol% CaO.

Another exemplary glass composition suitable for use in a substrate or component comprises: 60-70 mol% SiO₂(ii) a 6-14 mol% Al₂O₃(ii) a 0-15 mol% of B₂O₃0-15 mol% of L i₂O; 0-20 mol% Na₂O; 0-10 mol% of K₂O; 0-8 mol% MgO; 0-10 mol% CaO; 0-5 mol% of ZrO₂(ii) a 0-1 mol% of SnO₂(ii) a 0-1 mol% of CeO₂(ii) a Less than 50ppm of As₂O₃(ii) a And less than 50ppm Sb₂O₃Wherein 12 mol% is less than or equal to (L i)₂O+Na₂O+K₂O) is less than or equal to 20 mol percent, and (MgO + CaO) is less than or equal to 0 mol percent and less than or equal to 10 mol percent.

Another exemplary glass composition suitable for a substrate or component comprises: 63.5-66.5 mol% SiO₂(ii) a 8-12 mol% Al₂O₃(ii) a 0-3 mol% B₂O₃0 to 5 mol% L i₂O; 8-18 mol% Na₂O; 0-5 mol% K₂O; 1-7 mol% MgO; 0-2.5 mol% CaO; 0-3 mol% ZrO₂(ii) a 0.05-0.25 molMol% SnO₂(ii) a 0.05-0.5 mol% CeO₂(ii) a Less than 50ppm of As₂O₃(ii) a And less than 50ppm Sb₂O₃Wherein 14 mol% is less than or equal to (L i)₂O+Na₂O+K₂O) is less than or equal to 18 mol percent, and 2 mol percent is less than or equal to (MgO + CaO) is less than or equal to 7 mol percent.

In some embodiments, an alkali aluminosilicate glass composition suitable for use in a substrate or component comprises: alumina; at least one alkali metal; and, in some embodiments, greater than 50 mole% SiO₂And in other embodiments 58 mole% or more SiO₂And in other embodiments 60 mole% or more SiO₂In which ratio (Al)₂O₃+B₂O₃) The/sigma modifier is greater than 1, wherein the components are in proportions, in mole%, and the modifier is an alkali metal oxide. In particular embodiments, such glass compositions comprise: 58-72 mol% SiO₂(ii) a 9-17 mol% Al₂O₃(ii) a 2-12 mol% of B₂O₃(ii) a 8-16 mol% Na₂O; and 0-4 mol% of K₂O, wherein ratio (Al)₂O₃+B₂O₃) Sigma modifier>1。

In some embodiments, the substrate or component may comprise an alkali aluminosilicate glass composition comprising: 64-68 mol% SiO₂(ii) a 12-16 mol% Na₂O; 8-12 mol% Al₂O₃(ii) a 0-3 mol% of B₂O₃(ii) a 2-5 mol% of K₂O; 4-6 mol% MgO; and 0-5 mol% of CaO, wherein SiO is more than or equal to 66 mol%₂+B₂O₃CaO is less than or equal to 69 mol%; na (Na)₂O+K₂O+B₂O₃+MgO+CaO+SrO>10 mol%; MgO, CaO and SrO are more than or equal to 5 mol% and less than or equal to 8 mol%; (Na)₂O+B₂O₃)-Al₂O₃Less than or equal to 2 mol percent; na is not more than 2 mol percent₂O-Al₂O₃Less than or equal to 6 mol percent; and 4 mol% is less than or equal to (Na)₂O+K₂O)-Al₂O₃Less than or equal to 10 mol percent.

In some embodiments, the substrate or component may comprise an alkali aluminosilicate glass composition comprising: 2 mol% or more of Al₂O₃And/or ZrO₂Or 4 mol% or more of Al₂O₃And/or ZrO₂。

In embodiments including strengthened glass-based components, such strengthened components may be chemically strengthened by an ion exchange process. In the ion exchange process, ions on or near the surface of the glass or glass ceramic substrate are exchanged with the larger metal ions of the salt bath, typically by immersing the glass-based substrate in a molten salt bath for a predetermined period of time. In some embodiments, the molten salt bath has a temperature of about 400 ℃ to about 430 ℃ and the predetermined time is about 4 to about 12 hours. By incorporating larger ions in a glass or glass-ceramic substrate, the substrate is strengthened by creating compressive stress in a near-surface region of the substrate or a region located at and adjacent to a surface of the substrate. A corresponding tensile stress is induced in a central region or spaced apart from the surface of the substrate to balance the compressive stress. Glass or glass-ceramic substrates that employ such strengthening processes may be more particularly described as chemically strengthened or ion exchanged glass or glass-ceramic substrates.

In some examples, sodium ions in a chemically strengthened glass-based substrate are replaced by potassium ions in a molten salt bath (e.g., a potassium nitrate bath), but other alkali metal ions with larger atomic radii (e.g., rubidium or cesium) may also replace smaller alkali metal ions in the glass. According to some embodiments, the smaller alkali metal ions in the glass or glass-ceramic may be replaced by Ag⁺Ion replacement to provide an antimicrobial effect. Similarly, other alkali metal salts, such as, but not limited to, sulfates, phosphates, halides, and the like, may be used in the ion exchange process.

Replacing smaller ions with larger ions at temperatures below that at which relaxation of the glass network would occur creates an ion distribution on the surface of the strengthened substrate, which results in a stress profile. The larger volume of the incoming ions creates CS on the surface, creating tension (central tension, or CT) in the center of the strengthening substrate.

Compressive Stress, including surface CS, is measured by a surface Stress meter (FSM) using a commercial instrument such as FSM-6000 manufactured by Japan atomic laboratory co., L td (Japan)), which relies on the precise measurement of the Stress Optical Coefficient (SOC), which is related to the birefringence of the Glass, and then the SOC is measured according to protocol C (Method of Glass disks) described in ASTM Standard C770-16, entitled "Standard Test Method for measuring Glass Stress-Optical Coefficient", the entire contents of which is incorporated herein by reference.

In one or more embodiments, the surface compressive stress of the glass-based substrate can be 750MPa or greater, for example, 800MPa or greater, 850MPa or greater, 900MPa or greater, 950MPa or greater, 1000MPa or greater, 1150MPa or greater, or 1200 MPa.

As used herein, DOC represents the depth of change in stress from compression to tension in a chemically strengthened alkali aluminosilicate glass article described herein, depending on the ion exchange process, DOC can be measured by FSM or scattered light polarizers (SCA L P.) when stress is generated in the glass article by exchanging potassium ions into the glass article, DOC is measured using FSM. when stress is generated in the glass article by exchanging sodium ions into the glass article, DOC is measured using SCA L P. when stress is generated in the glass article by exchanging both potassium and sodium ions into the glass, DOC is measured by SCA L P because it is believed that the depth of exchange of sodium represents DOC and the depth of exchange of potassium ions represents the change in the magnitude of compressive stress (rather than the change in stress from compression to tension), in such glass articles the depth of exchange of potassium ions is measured by FSM.

The maximum CT value was measured using the scattered light polarizer (SCA L P) technique known in the art.

Examples of glass compositions are provided above. In some embodiments, the glass compositions disclosed in U.S. patent No. 9,156,724 ("the' 724 patent") can be used to form glass-based substrates or components. The' 724 patent discloses a baseAluminosilicate glass which is resistant to damage by sharp impact and which is capable of rapid ion exchange. Examples of such alkali aluminosilicate glasses include 4 mol% or more of P₂O₅And when ion exchanged, has the following vickers crack initiation thresholds: about 3kgf or greater, about 4kgf or greater, about 5kgf or greater, about 6kgf or greater, or about 7kgf or greater, and all ranges and subranges therebetween. In some embodiments, the first strengthened substrate comprises an alkali aluminosilicate glass comprising: about 4 mol% or more of P₂O₅And 0 to about 4 mol% of B₂O₃Wherein the alkali aluminosilicate glass does not contain L i₂O, and wherein, 1.3<[(P₂O₅+R₂O)/M₂O₃]Less than or equal to 2.3, wherein M is₂O₃＝Al₂O₃+B₂O₃And R₂O is the sum of monovalent cationic oxides present in the alkali aluminosilicate glass. In some embodiments, such alkali aluminosilicate glasses comprise less than 1 mol% K₂O, e.g. 0 mol% K₂And O. In some embodiments, such alkali aluminosilicate glasses comprise less than 1 mol% B₂O₃E.g. 0 mol% B₂O₃. In some embodiments, such alkali aluminosilicate glasses are ion exchanged to a depth of layer of about 10 μm or greater, and a compressive stress layer of the alkali aluminosilicate glass extends from a surface of the glass to the depth of layer, and wherein the compressive layer is at a compressive stress of about 300MPa or greater. In some embodiments, such alkali aluminosilicate glasses comprise monovalent and divalent cation oxides selected from the group consisting of: na (Na)₂O、K₂O、Rb₂O、Cs₂O, MgO, CaO, SrO, BaO and ZnO. In some embodiments, such alkali aluminosilicate glasses comprise: about 40 to about 70 mol% SiO₂(ii) a About 11 to about 25 mol% Al₂O₃(ii) a About 4 to about 15 mole% of P₂O₅(ii) a And about 13 to about 25 mole% Na₂And O. Made from the glass composition described immediately aboveThe substrate or component of glass may be ion exchanged.

In one or more embodiments, the glass composition described in U.S. patent application publication No. 20150239775 can be used to make a glass-based substrate that can be coated to provide a part or covering as described herein. U.S. patent application publication No. 20150239775 describes a glass-based article having a compressive stress profile that includes two linear portions: the first portion extends from the surface to a shallower depth and has a steep slope; and the second portion extends from the shallow depth to a compressed depth; these compressive stresses may be imparted to the glass-based substrates described herein.

Examples of coatings are provided above. An example of a coating is a scratch resistant coating. The scratch resistant coating may exhibit a hardness of about 9GPa or greater as measured by the berkovich indenter hardness test. The scratch-resistant coating of some embodiments may exhibit a refractive index of about 1.7 or greater. The scratch-resistant coating may include one or more of the following: AlN, Si₃N₄、AlO_xN_y、SiO_xN_y、Al₂O₃、Si_xC_y、Si_xO_yC_z、ZrO₂、TiO_xN_yDiamond, diamond-like carbon and Si_uAl_vO_xN_y。

In one or more embodiments, the scratch-resistant coating exhibits a hardness of about 9GPa to about 30GPa as measured by a berkovich indenter hardness test (from the major surface of the scratch-resistant coating). In one or more embodiments, the scratch resistant layer or coating exhibits a hardness in the following range: from about 10GPa to about 30GPa, from about 11GPa to about 30GPa, from about 12GPa to about 30GPa, from about 13GPa to about 30GPa, from about 14GPa to about 30GPa, from about 15GPa to about 30GPa, from about 9GPa to about 28GPa, from about 9GPa to about 26GPa, from about 9GPa to about 24GPa, from about 9GPa to about 22GPa, from about 9GPa to about 20GPa, from about 12GPa to about 25GPa, from about 15GPa to about 25GPa, from about 16GPa to about 24GPa, from about 18GPa to about 22GPa, and all ranges and subranges therebetween. In one or more embodiments, the scratch-resistant coating may exhibit a hardness of greater than 15GPa, greater than 20GPa, or greater than 25 GPa. In one or more embodiments, the scratch resistant layer exhibits a hardness of about 15GPa to about 150GPa, about 15GPa to about 100GPa, or about 18GPa to about 100 GPa. These hardness values may be exhibited at indentation depths of about 50nm or greater or about 100nm or greater (e.g., about 100nm to about 300nm, about 100nm to about 400nm, about 100nm to about 500nm, about 100nm to about 600nm, about 200nm to about 300nm, about 200nm to about 400nm, about 200nm to about 500nm, or about 200nm to about 600 nm).

The scratch-resistant coating may have a physical thickness ranging from about 1.5 μm to about 3 μm. In some embodiments, the physical thickness range of the scratch-resistant coating may be as follows: about 1.5 μm to about 3 μm, about 1.5 μm to about 2.8 μm, about 1.5 μm to about 2.6 μm, about 1.5 μm to about 2.4 μm, about 1.5 μm to about 2.2 μm, about 1.5 μm to about 2 μm, about 1.6 μm to about 3 μm, about 1.7 μm to about 3 μm, about 1.8 μm to about 3 μm, about 1.9 μm to about 3 μm, about 2 μm to about 3 μm, about 2.1 μm to about 3 μm, about 2.2 μm to about 3 μm, about 2.3 μm to about 3 μm, and all ranges and subranges therebetween. In some embodiments, the scratch-resistant coating may have a physical thickness ranging from about 0.1 μm to about 2 μm or from about 0.1 μm to about 1 μm or from 0.2 μm to about 1 μm.

In one or more embodiments, the scratch resistant layer has a refractive index of about 1.6 or greater. In some embodiments, the refractive index of the scratch-resistant coating can be about 1.65 or greater, 1.7 or greater, 1.8 or greater, 1.9 or greater, 2 or greater, or 2.1 or greater (e.g., about 1.8 to about 2.1 or about 1.9 to about 2.0). The refractive index of the scratch-resistant coating may be greater than the refractive index of the glass-based substrate 210. In some embodiments, the scratch-resistant coating has a refractive index that is about 0.05 refractive index units greater or about 0.2 refractive index units greater than the refractive index of the substrate when measured at a wavelength of about 550 nm.

The mathematical processes described above are readily performed using a variety of computer equipment, including personal computers, workstations, mainframes, and the like. The output from the program can be in electronic and/or hard copy form, and can be displayed in a variety of formats, including tabular and graphical forms. Software code (including the data input path of a commercial software package) may be stored and/or distributed in various forms, such as on a hard disk, floppy disk, CD, flash drive, etc.

While the foregoing is directed to various embodiments, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.