Glass and method of making same, glass assembly, vehicle
By defining the compressive stress and thickness relationship of a multi-layered stress structure in chemically tempered glass, the problem of easy crack propagation in thin chemically tempered glass is solved, improving the shatter resistance and surface needle drop performance, while maintaining the ability to resist bending cracks.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- FUYAO GLASS IND GROUP CO LTD
- Filing Date
- 2024-02-27
- Publication Date
- 2026-07-14
AI Technical Summary
The surface of chemically tempered thin glass is prone to crack propagation after being impacted by hard, sharp objects, resulting in poor surface needle resistance. Furthermore, it is difficult to balance the resistance to bending breakage and shattering strength while maintaining the thinness.
By defining the compressive stress and thickness relationship in the first, second, and third zones of the glass, a multi-layered stress structure is formed using thermal strengthening, first ion exchange, and second ion exchange processes. This ensures that impact or impact cracks are unlikely to enter the center of the glass, combined with appropriate central tensile stress control.
It improves the shatter resistance and surface pin drop performance of chemically tempered glass, while maintaining a relatively thin thickness and the flexural breakage resistance of general chemically strengthened glass.
Smart Images
Figure CN118084323B_ABST
Abstract
Description
Technical Field
[0001] This application belongs to the field of glass technology, specifically relating to glass and its preparation methods, glass components, and vehicles. Background Technology
[0002] In the field of glass technology, chemically tempered thin glass possesses the ability to resist bending and cracking at a general chemical strengthening level, and is relatively thin. However, when the surface of chemically tempered thin glass is impacted by a hard, sharp object, cracks are prone to propagation, resulting in lower needle drop performance on the surface of chemically tempered laminated glass. Summary of the Invention
[0003] In view of this, the first aspect of this application provides a glass having a first region, a second region, and a third region, wherein the second region is located within the first region, the third region is located within the second region, and the first region, the second region, and the third region all extend from the outer surface of the glass towards the center of the glass. The glass satisfies the following conditions: (CS0+CS1)*DOL1+(CS1+CS2)*(DOL2-DOL1)+CS2*(DOL3-DOL2)≤24*t, and CS0≥600MPa, DOL1+DOL2+DOL3≥0.25t;
[0004] Wherein, CS0 represents the surface compressive stress of the glass, CS1 represents the inflection point stress of the glass between the first and second ion exchange processes, DOL1 represents the inflection point depth of the glass between the first and second ion exchange processes, CS2 represents the inflection point stress of the glass between the thermal strengthening process and the first ion exchange process, DOL2 represents the inflection point depth of the glass between the thermal strengthening process and the first ion exchange process, DOL3 represents the stress depth of the glass during the thermal strengthening process, and t represents the thickness of the glass.
[0005] The glass provided in the first aspect of this application defines the relationship between CS0, CS1, DOL1, CS2, DOL2, DOL3, and t through the above formula, so that the first, second, and third zones of the glass can cooperate with each other to improve the shatter resistance of the glass, so that after the glass is subjected to impact, the crack will not propagate and cannot enter the center of the glass.
[0006] In related technologies, when glass is subjected to general severe scratches, impact from sharp objects, or other impact defects, the impact or crack must pass through the outer surface of the glass to reach its center, resulting in glass shattering. However, in this application, when glass is subjected to general severe scratches, impact from sharp objects, or other impact defects, the impact or crack must pass through the third zone, a portion of the second zone excluding the third zone, and a portion of the first zone excluding the second zone before reaching the center of the glass. In other words, when glass is subjected to general severe scratches, impact from sharp objects, or other impact defects, the impact or crack must pass through the third zone, the second zone, and the first zone before reaching the center of the glass.
[0007] Specifically, by using the above formula, the relationship between CS0, CS1, DOL1, CS2, DOL2, DOL3, and t is defined, thereby defining the compressive stress in the third zone, the compressive stress in the second zone excluding the third zone, and the compressive stress in the first zone excluding the second zone. Combined with the thickness settings of the third zone, the second zone excluding the third zone, and the first zone excluding the second zone, it is difficult for impact or impact cracks to break through the third zone, the second zone, and the first zone, and it is difficult for them to enter the center of the glass, thereby improving the glass's shatter resistance.
[0008] (CS0+CS1)*DOL1+(CS1+CS2)*(DOL2-DOL1)+CS2*(DOL3-DOL2)≤24*t is mainly used to limit the compressive stress in the first, second, and third zones, improving the glass's shatter resistance while reducing the tensile stress in the central zone, thereby improving the glass's surface resistance to needle strikes. CS0≥600MPa is mainly used to maintain the glass's ability to resist bending fracture at a general chemical strengthening level. DOL1+DOL2+DOL3≥0.25t is mainly used to ensure that the glass has the highest possible total stress layer depth at a relatively thin thickness to resist the penetration of sharp objects into the tensile stress layer. The above three limiting formulas work together to limit the compressive stress in each zone of the glass, the thickness of each zone, and the overall glass thickness.
[0009] Therefore, this application can improve the glass’s resistance to bending cracks by defining the relationship between CS0, CS1, DOL1, CS2, DOL2, DOL3, and t through a formula, while maintaining the glass’s general chemical strengthening level and thinner glass thickness. This allows the first, second, and third zones of the glass to cooperate with each other, thereby improving the glass’s resistance to general heavy scratches, sharp object compression, and impact defects, and thus improving the glass’s surface needle drop performance.
[0010] In the glass, CS0, CS1, and DOL1 satisfy the following conditions: 600MPa≤CS0≤900MPa, 200MPa≤CS1≤300MPa, and 0.005mm≤DOL1≤0.015mm.
[0011] In the glass, CS2 and DOL2 satisfy the following conditions: 5MPa≤CS2≤15MPa, 0.035mm≤DOL2≤0.055mm.
[0012] In the glass, DOL3 and t satisfy the following conditions: DOL3≥0.25t, 0.7mm≤t≤1.2mm.
[0013] The glass also satisfies the following condition: (CS0-CS1) / DOL1≥2.5*(CS1-CS2) / (DOL2-DOL1).
[0014] The central tensile stress CT of the glass satisfies the following condition: CT≤30MPa.
[0015] The first region is formed by a thermal intensification process, the second region is formed by a first ion exchange process, and the third region is formed by a second ion exchange process.
[0016] A second aspect of this application provides a method for preparing glass, the method comprising:
[0017] Provide the glass to be processed;
[0018] The glass to be processed is subjected to a heat strengthening process to obtain a first strengthened glass;
[0019] The first tempered glass is subjected to a first ion exchange process to obtain the second tempered glass;
[0020] The second tempered glass is subjected to a second ion exchange process to obtain the glass provided in the first aspect of this application.
[0021] The glass preparation method of the second aspect of this application, by preparing the glass provided in the first aspect of this application, can improve the glass's resistance to bending fracture while maintaining the glass's general chemical strengthening level and its relatively thin thickness. By defining the relationship between CS0, CS1, DOL1, CS2, DOL2, DOL3, and t through a formula, the first, second, and third zones of the glass can cooperate with each other, thereby improving the glass's resistance to general heavy scratches, sharp object compression, and impact defects, and further improving the glass's surface needle drop performance.
[0022] The step of performing a heat-strengthening process on the glass to be treated includes:
[0023] The surface compressive stress σ1 of the glass to be treated is made to satisfy the following conditions: 5MPa≤σ1≤15MPa, and the values of DOL3 and t in the glass to be treated satisfy: DOL3≥0.25t, 0.7mm≤t≤1.2mm, thus obtaining the first tempered glass.
[0024] In the heat strengthening process, the glass to be treated is heated to a temperature of T1, and the heated glass is cooled to a pressure of P. T1 and P satisfy the following conditions: 550℃≤T1≤750℃, 50mmWC≤P≤220mmWC.
[0025] The step of performing a first ion exchange process on the first tempered glass includes:
[0026] The surface compressive stress σ2 of the first tempered glass is made to satisfy the following conditions: 300MPa≤σ2≤500MPa, and in the first tempered glass, CS2 and DOL2 satisfy the following conditions: 5MPa≤CS2≤15MPa, 0.035mm≤DOL2≤0.055mm, to obtain the second tempered glass.
[0027] During the first ion exchange process, the first tempered glass satisfies one of the following:
[0028] A mixed salt bath of potassium nitrate and sodium nitrate is used; wherein the mass ratio of potassium nitrate to sodium nitrate is (80-95):(5-20), and the temperature of the first ion exchange process is T2 and the time is C1, wherein T2 and C1 satisfy the following conditions: 380℃≤T2≤450℃, 60min≤C1≤150min;
[0029] A potassium nitrate salt bath is used; wherein, the proportion of potassium nitrate in the salt is not less than 95%, and the first ion exchange process includes a daughter ion exchange process and a daughter ion migration process. The temperature of the daughter ion exchange process is T3 and the time is C2, and T3 and C2 satisfy the following conditions: 380℃≤T3≤450℃, 50min≤C2≤100min; the daughter ion migration process is not immersed in the potassium nitrate salt bath, but is completed in air, and the migration temperature is T4 and the migration time is C3, and T4 and C3 satisfy the following conditions: 450℃≤T4≤500℃, 10min≤C3≤60min;
[0030] An ion exchange barrier layer is formed on the first tempered glass, and a potassium nitrate salt bath is used; wherein, the proportion of potassium nitrate in the salt is not less than 95%, and the temperature of the first ion exchange process is T5 and the time is C4, and T5 and C4 satisfy the following conditions: 380℃≤T5≤450℃, 90min≤C4≤180min.
[0031] The step of performing a second ion exchange process on the second tempered glass includes:
[0032] The surface compressive stress σ3 of the second tempered glass is made to satisfy the following conditions: 600MPa≤σ3≤900MPa, and in the second tempered glass, CS1 and DOL1 satisfy the following conditions: 200MPa≤CS1≤300MPa, 0.005mm≤DOL1≤0.015mm, thus obtaining the glass.
[0033] In the second ion exchange process, a potassium nitrate salt bath is used; wherein the proportion of potassium nitrate in the salt is not less than 95%, and the temperature of the second ion exchange process is T6 and the time is C5, wherein T6 and C5 satisfy the following conditions: 400℃≤T6≤450℃, 120s≤C5≤600s.
[0034] A third aspect of this application provides a glass assembly comprising an intermediate layer, a first glass, and a second glass, wherein the first glass is the glass provided in the first aspect of this application, and the first glass and the second glass are respectively disposed on opposite sides of the intermediate layer.
[0035] The glass assembly provided in the third aspect of this application, by adopting the glass provided in the first aspect of this application, can, while maintaining the first glass's ability to resist bending cracks at a general chemical strengthening level and having a relatively thin thickness, limit the relationship between CS0, CS1, DOL1, CS2, DOL2, DOL3, and t through a formula, so that the first, second, and third regions of the first glass can cooperate with each other, thereby improving the first glass's resistance to shattering after general heavy scratches, sharp object compression, and impact defects, and thus improving the surface needle drop performance of the first glass.
[0036] Specifically, when a needle with a diameter of 4.6 mm, a length of 25 mm, a total mass of 3.2 g, and a diamond tip angle of 120° is dropped onto the surface of the first glass away from the intermediate layer, the needle height H1 of the first glass away from the intermediate layer satisfies the following condition: H1 ≥ 200 mm.
[0037] Specifically, when a needle with a diameter of 4.6 mm, a length of 25 mm, a total mass of 3.2 g, and a diamond tip angle of 120° is dropped onto the surface of the second glass away from the intermediate layer, the needle height H2 away from the surface of the second glass away from the intermediate layer satisfies the following condition: H2 ≥ 300 mm.
[0038] A fourth aspect of this application provides a vehicle including a body and a glass assembly as provided in a third aspect of this application, the glass assembly being mounted on the body; wherein, in the glass assembly, a first glass is closer to the interior space of the body than a second glass.
[0039] The vehicle provided in the fourth aspect of this application, by adopting the glass assembly provided in the third aspect of this application, allows the first glass in the glass assembly to maintain the ability of the first glass to resist bending cracks at a general chemical strengthening level and to have a relatively thin thickness. By defining the relationship between CS0, CS1, DOL1, CS2, DOL2, DOL3, and t through a formula, the first, second, and third zones of the first glass can cooperate with each other, thereby improving the first glass's resistance to shattering after general heavy scratches, sharp object compression, and impact defects, and further improving the surface needle drop performance of the first glass. Attached Figure Description
[0040] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the embodiments of this application will be described below.
[0041] Figure 1 This is a schematic curve showing the distribution of glass thickness and compressive stress in one embodiment of this application.
[0042] Figure 2 This is a schematic diagram of the glass structure in one embodiment of this application.
[0043] Figure 3 A process flow diagram of a glass preparation method according to one embodiment of this application.
[0044] Figure 4 This is a schematic diagram of the structure of the glass assembly in one embodiment of this application.
[0045] Labeling explanation: Glass-1, Zone 1-11, Zone 2-12, Zone 3-13, Glass assembly-2, First glass-21, Intermediate layer-22, Second glass-23. Detailed Implementation
[0046] The following are preferred embodiments of this application. It should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the principles of this application, and these improvements and modifications are also considered to be within the scope of protection of this application.
[0047] Before introducing the technical solution of this application, let's go over the technical issues in related technologies in detail.
[0048] Ultra-thin chemically tempered glass with a thickness of 1.1 mm or less, when used in laminated automotive windows, reduces the overall thickness of the glass and improves the overall bending strength and stiffness of the laminated glass. However, thin chemically tempered glass is susceptible to scratches, bumps, and impacts from hard objects in the environment of vehicle use, resulting in localized damage (e.g., point impact damage or linear scratches). When the depth of the localized damage reaches or approaches the depth obtained by one ion exchange strengthening process, under the action of central tensile stress, the localized damage is very likely to extend and prolong, thus forming a large-area crack that extends from the damage point along one or more directions to the edge of the glass, forming a shard.
[0049] In the field of automotive glass, the drop needle test (also known as the sand and gravel test) is generally used to evaluate the crack propagation characteristics of glass surfaces after being damaged by uncertain hard objects. The test procedure is as follows: a steel cylinder with a diamond tip (hereinafter referred to as "drop needle": diameter 4.6mm, length 25mm, total mass 3.2g, diamond tip angle 120°, and top tip radius of curvature 0.1mm) is placed in a rigid straight tube and dropped freely. Starting from the minimum drop height (hmin), impacts are performed at all designated impact points. The minimum drop height (hmin) is the height of the preset minimum impact resistance requirement. Then, the height is increased by 50mm each time, and impacts are performed until the glass breaks. The distance between each impact point should be at least 4mm. The maximum height at which the glass edge and center can withstand the drop needle impact without crack propagation is measured. The needle drop height is mainly related to the glass thickness and stress distribution, showing that the greater the glass strengthening stress, the lower the needle drop height. Existing experiments show that the greater the central tensile stress of the glass, the lower the needle drop height it can withstand. The needle drop height of different strengthening states of glass of the same thickness can be ranked as follows: original sheet > physically thermally strengthened > physically semi-tempered > physically fully tempered (inversely correlated with the glass strengthening range). For chemically tempered glass, since the stress layer thickness is on the micrometer scale, its central tensile stress is strongly correlated with the glass thickness. When the thickness of chemically tempered glass is above 2mm, its needle drop height is comparable to that of physically semi-tempered glass. However, when the glass thickness is further reduced (≤1.1mm), with the surface compressive stress and stress layer depth remaining unchanged, the central tensile stress of the glass increases significantly. At this point, the needle drop height is even lower than that of physically fully tempered glass. This results in a significant reduction in the glass's ability to resist impacts from high-hardness sharp objects without cracking, despite its high bending strength. In other words, the glass surface has a very low tolerance for new defects, and crack propagation occurs even from minor damage. In practice, there have been reports of occasional cracking phenomena.
[0050] However, although the original glass and glass under low stress have high needle drop performance, automotive glass also needs to have a certain ability to resist bending deformation without breaking. This mechanical property is strongly positively correlated with the compressive stress on the glass surface. Therefore, it is contradictory to want both high bending strength and good needle drop performance for glass with a thickness of less than 1.2mm. Under current technology, it is often impossible to achieve both simultaneously.
[0051] Therefore, to address the aforementioned problems, this application provides a glass that solves the issue of crack propagation easily caused by impacts from hard, sharp objects on the surface of chemically tempered thin glass. It improves the needle-drop resistance of the inner surface of chemically tempered laminated glass, enabling the tempered glass surface to withstand general heavy scratches. Defects caused by sharp object compression or impact are less likely to propagate, reducing the probability of spontaneous cracking. Furthermore, it maintains the thin glass's resistance to bending fracture at a general chemical strengthening level, resolving the problem that these two contradictory mechanical properties cannot be simultaneously achieved in glass with a thickness of 1.2 mm or less.
[0052] Please refer to this as well. Figures 1-2 , Figure 1 This is a schematic curve showing the distribution of glass thickness and compressive stress in one embodiment of this application. Figure 2 This is a schematic diagram of the glass structure in one embodiment of this application.
[0053] This embodiment provides a glass 1 having a first region 11, a second region 12, and a third region 13. The second region 12 is located within the first region 11, and the third region 13 is located within the second region 12. The first region 11, the second region 12, and the third region 13 all extend from the outer surface of the glass 1 to the center of the glass 1. The glass 1 satisfies the following conditions: (CS0+CS1)*DOL1+(CS1+CS2)*(DOL2-DOL1)+CS2*(DOL3-DOL2)≤24*t, and CS0≥600MPa, DOL1+DOL2+DOL3≥0.25t.
[0054] Wherein, CS0 represents the surface compressive stress of glass 1, CS1 represents the inflection point stress of glass 1 between the first and second ion exchange processes, DOL1 represents the inflection point depth of glass 1 between the first and second ion exchange processes, CS2 represents the inflection point stress of glass 1 between the thermal strengthening process and the first ion exchange process, DOL2 represents the inflection point depth of glass 1 between the thermal strengthening process and the first ion exchange process, DOL3 represents the stress depth of glass 1 during the thermal strengthening process, and t represents the thickness of glass 1.
[0055] In one embodiment, the first region 11 is formed by a thermal intensification process, the second region 12 is formed by a first ion exchange process, and the third region 13 is formed by a second ion exchange process.
[0056] like Figure 2As shown, the first region 11 can be understood as the region formed by the thermal strengthening process of glass 1. The second region 12 is located within the first region 11, and the second region 12 can be understood as the region formed by both the thermal strengthening process and the first ion exchange process. The third region 13 is located within the second region 12, that is, the third region 13 is also located within the first region 11, and the third region 13 can be understood as the region formed not only by the thermal strengthening process, but also by the first and second ion exchange processes. Furthermore, the first region 11, the second region 12, and the third region 13 all extend from the outer surface of glass 1 towards the center of glass 1.
[0057] Glass 1 first undergoes a thermal strengthening process to form the first region 11, then a first ion exchange process to form the second region 12, and finally a second ion exchange process to form the third region 13. Within glass 1, the relationships between CS0, CS1, DOL1, CS2, DOL2, DOL3, and t conform to the aforementioned formula. This allows the first region 11, second region 12, and third region 13 of glass 1 to work together to improve the shatter resistance of glass 1. This ensures that after impact, cracks will not propagate towards the center of glass 1 and will not penetrate its core. It should be noted that when an impact-induced defect reaches the central tensile stress layer, the crack will propagate horizontally outwards under the influence of the central tensile stress. In other words, the deeper compressive stress layer DOL aims to prevent impact defects from easily reaching the central tensile stress layer, while controlling the central tensile stress prevents crack propagation after the defect reaches the central tensile stress layer.
[0058] CS0 represents the surface compressive stress on the outer surface of glass 1. CS1 also represents the compressive stress at the interface between the third region 13 (far from the outer surface of glass 1) and the second region 12. DOL1 also represents the thickness of the third region 13. CS2 also represents the compressive stress at the interface between the second region 12 (far from the outer surface of glass 1) and the first region 11. DOL2 also represents the thickness of the second region 12. DOL3 also represents the thickness of the first region 11.
[0059] Optionally, the compressive stress in the third region 13 is greater than the compressive stress in the second region 12 excluding the third region 13. The compressive stress in the second region 12 excluding the third region 13 is greater than the compressive stress in the first region 11 excluding the second region 12.
[0060] Optionally, the thickness of the third region 13 is less than the thickness of the portion of the second region 12 excluding the third region 13. The thickness of the portion of the second region 12 excluding the third region 13 is less than the thickness of the portion of the first region 11 excluding the second region 12.
[0061] Optionally, the glass 1 further includes a central region, which is located further away from the outer surface of the glass 1 than the first region 11, and the first region 11 is disposed around the central region; the tensile stress in the central region is less than the compressive stress in the first region 11. Further optionally, the tensile stress in the central region is less than the compressive stress in the portion of the first region 11 excluding the second region 12. Further optionally, the thickness of the central region is greater than the thickness of the first region 11. Even further optionally, the thickness of the central region is greater than the thickness of the portion of the first region 11 excluding the second region 12.
[0062] In related technologies, when glass 1 is subjected to general severe scratches, sharp object compression, or impact defects, the impact or impact crack must pass through the outer surface of glass 1 and enter the center of glass 1, causing glass 1 to shatter. However, in this application, when glass 1 is subjected to general severe scratches, sharp object compression, or impact defects, the impact or impact crack must pass through the third zone 13, the portion of the second zone 12 excluding the third zone 13, and the portion of the first zone 11 excluding the second zone 12 before entering the center of glass 1. In other words, when glass 1 is subjected to general severe scratches, sharp object compression, or impact defects, the impact or impact crack must pass through the third zone 13, the second zone 12, and the first zone 11 before entering the center of glass 1.
[0063] Specifically, by using the above formula, the relationship between CS0, CS1, DOL1, CS2, DOL2, DOL3, and t is defined, thereby defining the compressive stress in the third zone 13, the compressive stress in the second zone 12 excluding the third zone 13, and the compressive stress in the first zone 11 excluding the second zone 12. Combined with the thickness settings of the third zone 13, the second zone 12 excluding the third zone 13, and the first zone 11 excluding the second zone 12, it is difficult for impact or impact cracks to break through the third zone 13, the second zone 12, and the first zone 11, and it is difficult for them to enter the center of the glass 1, thereby improving the shatter resistance of the glass 1.
[0064] (CS0+CS1)*DOL1+(CS1+CS2)*(DOL2-DOL1)+CS2*(DOL3-DOL2)≤24*t is mainly used to limit the compressive stress in the first zone 11, the second zone 12, and the third zone 13, thereby improving the shatter resistance of glass 1 and reducing the tensile stress value in the central zone to improve the surface needle drop performance of glass 1. CS0≥600MPa is mainly used to maintain the ability of glass 1 to resist bending fracture at a general chemical strengthening level. DOL1+DOL2+DOL3≥0.25t is mainly used to ensure that glass 1 has the highest possible total stress layer depth at a relatively thin thickness to resist the intrusion of sharp objects into the tensile stress layer, thereby improving the needle drop performance of glass 1. The above three limiting formulas work together to limit the compressive stress, the thickness of each zone, and the thickness of glass 1 in each zone.
[0065] Therefore, this embodiment can maintain the glass 1's ability to resist bending cracks at a general chemical strengthening level and the glass 1's relatively thin thickness. By defining the relationship between CS0, CS1, DOL1, CS2, DOL2, DOL3, and t through a formula, the first zone 11, the second zone 12, and the third zone 13 of the glass 1 can cooperate with each other, thereby improving the glass 1's resistance to shattering after general heavy scratches, sharp object compression, and impact defects, and thus improving the surface needle drop performance of the glass 1.
[0066] Please refer to this as well. Figures 1-2 In one embodiment, in the glass 1, CS0, CS1, and DOL1 satisfy the following conditions: 600MPa≤CS0≤900MPa, 200MPa≤CS1≤300MPa, and 0.005mm≤DOL1≤0.015mm.
[0067] Optionally, CS0 can be 650MPa, 700MPa, 750MPa, 800MPa, or 850MPa, etc. Optionally, CS1 can be 220MPa, 250MPa, or 280MPa, etc. Optionally, DOL1 can be 0.008mm, 0.010mm, or 0.012mm, etc.
[0068] In this embodiment, by limiting CS0 to 600MPa-900MPa, a high compressive stress is maintained on the outer surface of glass 1, thereby giving glass 1 a high resistance to bending fracture. Furthermore, by limiting CS0 and CS1, the compressive stress in the third region 13 decreases along the direction from the outer surface of glass 1 to its center, thereby improving the glass 1's resistance to shattering after general heavy scratches, sharp object compression, and impact defects, and thus improving the surface needle-drop performance of glass 1. Simultaneously, the relatively high compressive stresses of CS0 and CS1 give the third region 13 of glass 1 a high resistance to bending fracture. Moreover, by limiting DOL1, this embodiment maintains a relatively thin thickness in the third region 13 while improving the surface needle-drop performance of glass 1.
[0069] Please refer to this as well. Figures 1-2 In one embodiment, in the glass 1, CS2 and DOL2 satisfy the following conditions: 5MPa≤CS2≤15MPa, 0.035mm≤DOL2≤0.055mm.
[0070] Optionally, CS2 can be 8MPa, 10MPa, or 12MPa, etc. Optionally, DOL2 can be 0.040mm, 0.045mm, or 0.050mm, etc.
[0071] In this embodiment, by defining CS2, in conjunction with CS0 and CS1, the compressive stress in the third region 13 and the second region 12, excluding the third region 13, tends to decrease in the direction from the outer surface of the glass 1 to the center of the glass 1. In other words, the compressive stress in the second region 12 tends to decrease. This further improves the shatter resistance of the glass 1 after general heavy scratches, sharp object squeezing, and impact defects. It makes it difficult for impact or impact cracks to break through the third region 13 and the second region 12, excluding the third region 13, increasing the difficulty for impact or impact cracks to enter the center of the glass 1, thereby further improving the surface needle drop performance of the glass 1.
[0072] Furthermore, by limiting DOL2, this embodiment ensures that the portion of the second region 12 excluding the third region 13 maintains a relatively thin thickness while improving the needle-drop performance of the glass 1 surface. On the other hand, DOL2 can cooperate with DOL1 to make the thickness of the portion of the second region 12 excluding the third region 13 greater than the thickness of the third region 13, thereby making it more difficult for impacts or impact cracks to penetrate the portion of the second region 12 excluding the third region 13, further increasing the difficulty for impacts or impact cracks to enter the center of the glass 1, and further improving the needle-drop performance of the glass 1 surface.
[0073] Please refer to this as well. Figures 1-2 In one embodiment, in the glass 1, DOL3 and t satisfy the following conditions: DOL3≥0.25t, 0.7mm≤t≤1.2mm.
[0074] Optionally, t can be 0.9 mm, 1 mm, or 1.1 mm, etc. Optionally, DOL3 ≥ 0.175 mm. Further optionally, 0.175 mm ≤ DOL3 ≤ 0.3 mm. DOL3 can be 0.2 mm, 0.25 mm, or 0.28 mm, etc. Optionally, the compressive stress in the first region 11 portion away from the outer surface of glass 1 is 0 MPa.
[0075] In this embodiment, by defining the portion of the first zone 11 excluding the second zone 12, in conjunction with CS2, CS0, and CS1, the compressive stress in the third zone 13, the portion of the second zone 12 excluding the third zone 13, and the portion of the first zone 11 excluding the second zone 12 in the direction from the outer surface of the glass 1 to the center of the glass 1 tends to decrease. In other words, the compressive stress in the first zone 11 tends to decrease. This further improves the shatter resistance of the glass 1 after general heavy scratches, sharp object compression, and impact defects, making it difficult for impacts or impact cracks to break through the third zone 13, the portion of the second zone 12 excluding the third zone 13, and the portion of the first zone 11 excluding the second zone 12. This further increases the difficulty for impacts or impact cracks to enter the center of the glass 1, thereby further improving the surface needle drop performance of the glass 1.
[0076] Furthermore, this embodiment limits the relationship between DOL3 and t, ensuring that the portion of the first region 11 excluding the second region 12 maintains a relatively thin thickness while improving the needle-drop performance of the glass 1 surface. On the other hand, DOL3 can cooperate with DOL2 and DOL1 to make the thickness of the portion of the first region 11 excluding the second region 12 greater than the thickness of the portion of the second region 12 excluding the third region 13. This makes it more difficult for impacts or impact cracks to penetrate the portion of the first region 11 excluding the second region 12, further increasing the difficulty for impacts or impact cracks to enter the center of the glass 1, and further improving the needle-drop performance of the glass 1 surface.
[0077] Please refer to this as well. Figures 1-2 In one embodiment, the glass 1 also satisfies the following condition: (CS0-CS1) / DOL1≥2.5*(CS1-CS2) / (DOL2-DOL1).
[0078] This embodiment defines the relationship between the stress slope before the inflection point depth DOL1 and the stress slope between DOL1 and DOL2 using the above formula, thereby defining the stress change slope of the third region 13 and the second region 12 excluding the third region 13. This results in smaller compressive stress in the third region 13 and the second region 12 excluding the third region 13, making it more difficult for impact or impact cracks to penetrate the third region 13 and the second region 12 excluding the third region 13, and further improving the surface needle drop performance of glass 1.
[0079] In one embodiment, the central tensile stress CT of the glass 1 satisfies the following condition: CT≤30MPa.
[0080] Optionally, the central tensile stress CT can be 5 MPa, 10 MPa, 15 MPa, 20 MPa, or 25 MPa, etc. This embodiment, by using a central tensile stress CT relative to the glass 1, enables the glass 1 to have a lower central tensile stress, thereby improving the glass 1's resistance to breakage after general heavy scratches, sharp object compression, and impact defects, and further improving the surface needle drop performance of the glass 1.
[0081] Please refer to this as well. Figures 1-3 , Figure 3 A process flow diagram of a glass preparation method according to one embodiment of this application. This application also provides a method for preparing glass 1, the method comprising:
[0082] S100 provides glass to be processed.
[0083] S200, the glass to be processed is subjected to a heat strengthening process to obtain the first strengthened glass.
[0084] In one embodiment, the step of performing a heat-strengthening process on the glass to be treated includes:
[0085] The surface compressive stress σ1 of the glass to be treated is made to satisfy the following conditions: 5MPa≤σ1≤15MPa, and the values of DOL3 and t in the glass to be treated satisfy: DOL3≥0.25t, 0.7mm≤t≤1.2mm, thus obtaining the first tempered glass.
[0086] In one embodiment, during the heat strengthening process, the glass to be treated is heated to a temperature of T1, and the heated glass is cooled to a pressure of P. T1 and P satisfy the following conditions: 550℃≤T1≤750℃, 50mmWC≤P≤220mmWC.
[0087] Among them, the surface compressive stress formed by glass 1 is lower than that of physically tempered (cooling air pressure ≥ 600 mmWC) and physically semi-tempered (cooling air pressure ≥ 300 mmWC).
[0088] Optionally, the step of performing a heat strengthening process on the glass to be treated includes:
[0089] The glass to be processed is bent to make it bend.
[0090] During the heat strengthening process, which is performed above the Tg point of glass 1, the bending process of glass 1 can also be included simultaneously to form the desired shape. In subsequent processes, the first and second ion exchange processes are both performed below the Tg point of glass 1, without changing the shape of glass 1.
[0091] S300, the first tempered glass is subjected to a first ion exchange process to obtain the second tempered glass.
[0092] In one embodiment, the step of performing a first ion exchange process on the first tempered glass includes:
[0093] The surface compressive stress σ2 of the first tempered glass is made to satisfy the following conditions: 300MPa≤σ2≤500MPa, and in the first tempered glass, CS2 and DOL2 satisfy the following conditions: 5MPa≤CS2≤15MPa, 0.035mm≤DOL2≤0.055mm, to obtain the second tempered glass.
[0094] In one embodiment, during the first ion exchange process, the first tempered glass satisfies one of the following:
[0095] A mixed salt bath of potassium nitrate and sodium nitrate is used; wherein the mass ratio of potassium nitrate to sodium nitrate is (80-95):(5-20), and the temperature of the first ion exchange process is T2 and the time is C1. T2 and C1 satisfy the following conditions: 380℃≤T2≤450℃, 60min≤C1≤150min.
[0096] Alternatively, a potassium nitrate salt bath may be used; wherein the proportion of potassium nitrate in the salt is not less than 95%, and the first ion exchange process includes a daughter ion exchange process and a daughter ion migration process. The temperature of the daughter ion exchange process is T3 and the time is C2, and T3 and C2 satisfy the following conditions: 380℃≤T3≤450℃, 50min≤C2≤100min; the daughter ion migration process is not immersed in the potassium nitrate salt bath, but is completed in air, with a migration temperature of T4 and a migration time of C3, and T4 and C3 satisfy the following conditions: 450℃≤T4≤500℃, 10min≤C3≤60min;
[0097] In other words, a ≥95% potassium nitrate salt bath is used to exchange at 380℃-450℃ for 50min-100min, followed by ion migration at 450℃-500℃ for 10min-60min to reduce surface compressive stress and achieve the desired DOL2.
[0098] Alternatively, an ion exchange barrier layer is formed on the first tempered glass, and a potassium nitrate salt bath is used; wherein the proportion of potassium nitrate in the salt is not less than 95%, and the temperature of the first ion exchange process is T5 and the time is C4, and T5 and C4 satisfy the following conditions: 380℃≤T5≤450℃, 90min≤C4≤180min.
[0099] This embodiment provides a variety of technical solutions for the first ion exchange process, which can be selected and used flexibly according to the material and type of glass to be treated.
[0100] S400, the second strengthened glass is subjected to a second ion exchange process to obtain glass 1 as described above in this application.
[0101] In one embodiment, the step of performing a second ion exchange process on the second strengthened glass includes:
[0102] The surface compressive stress σ3 of the second tempered glass is made to satisfy the following conditions: 600MPa≤σ3≤900MPa, and in the second tempered glass, CS1 and DOL1 satisfy the following conditions: 200MPa≤CS1≤300MPa, 0.005mm≤DOL1≤0.015mm, thus obtaining the glass 1.
[0103] Where σ3 equals CS0, which is the surface compressive stress of the final glass 1.
[0104] In one embodiment, a potassium nitrate salt bath is used in the second ion exchange process; wherein the proportion of potassium nitrate in the salt is not less than 95%, and the temperature of the second ion exchange process is T6 and the time is C5, wherein T6 and C5 satisfy the following conditions: 400℃≤T6≤450℃, 120s≤C5≤600s.
[0105] Therefore, the glass 1 preparation method of this embodiment, by preparing the glass 1 provided above in this application, can maintain the glass 1's ability to resist bending cracks at a general chemical strengthening level and the glass 1's relatively thin thickness, and by defining the relationship between CS0, CS1, DOL1, CS2, DOL2, DOL3, and t by formula, enable the first region 11, the second region 12, and the third region 13 of the glass 1 to cooperate with each other, thereby improving the glass 1's resistance to breakage after general heavy scratches, sharp object compression, and impact defects, and further improving the surface needle drop performance of the glass 1.
[0106] Please refer to this as well. Figures 1-2 ,and Figure 4 , Figure 4 This is a schematic diagram of the structure of a glass assembly according to one embodiment of this application. This application also provides a glass assembly 2, which includes an intermediate layer 22, a first glass 21, and a second glass 23. The first glass 21 is the glass 1 provided above in this application. The first glass 21 and the second glass 23 are respectively disposed on opposite sides of the intermediate layer 22.
[0107] Optionally, the first glass 21 is aluminosilicate glass 1. Further optionally, the composition of the aluminosilicate glass 1 includes, but is not limited to, the following oxide components: 50%–70% SiO2, 4%–22% Al2O3, 8%–18% Na2O, 0%–5% Li2O, 0%–1% CaO, 1%–5% MgO, 0%–10% K2O, 0%–0.08% Fe2O3, 0%–2% ZrO2, and 0%–5% B2O3.
[0108] Optionally, the second glass 23 is soda-lime silicate glass 1. The thickness of the second glass 23 is 1.6 mm to 5.0 mm. The second glass 23 is physically strengthened.
[0109] In one embodiment, when a needle with a diameter of 4.6 mm, a length of 25 mm, a total mass of 3.2 g, and a diamond tip angle of 120° is dropped onto the surface of the first glass 21 away from the intermediate layer 22, the needle height H1 of the first glass 21 away from the surface of the intermediate layer 22 satisfies the following condition: H1 ≥ 200 mm.
[0110] Optionally, the needle drop height H1 can be 220mm, 240mm, or 250mm, etc. In this embodiment, the needle drop height H1 of the first glass 21 facing away from the intermediate layer 22 can be greater than 200mm. While maintaining the first glass 21's ability to resist bending cracks at a general chemical strengthening level and having a relatively thin thickness, the relationship between CS0, CS1, DOL1, CS2, DOL2, DOL3, and t is defined by a formula, so that the first region 11, the second region 12, and the third region 13 of the first glass 21 can cooperate with each other, thereby improving the first glass 21's resistance to breakage after general heavy scratches, sharp object compression, and impact defects, and thus improving the surface needle drop performance of the first glass 21.
[0111] In one embodiment, when a needle with a diameter of 4.6 mm, a length of 25 mm, a total mass of 3.2 g, and a diamond tip angle of 120° is dropped onto the surface of the second glass 23 away from the intermediate layer 22, the needle height H2 of the second glass 23 away from the surface of the intermediate layer 22 satisfies the following condition: H2 ≥ 300 mm.
[0112] In this embodiment, the needle drop height H2 of the second glass 23 facing away from the surface of the intermediate layer 22 in the glass assembly 2 can be greater than 300mm. This can be combined with the first glass 21 to improve the glass assembly 2's resistance to breakage after general heavy scratches, sharp object squeezing, and impact defects, thereby improving the surface needle drop performance of the glass 1.
[0113] This application provides a vehicle, the vehicle including a body and the glass assembly provided in this application as described above, the glass assembly being mounted on the body; wherein, in the glass assembly, a first glass is closer to the interior space of the body than a second glass.
[0114] The vehicle provided in this embodiment, by adopting the glass assembly provided above in this application, allows the first glass in the glass assembly to maintain the ability of the first glass to resist bending cracks at a general chemical strengthening level and to have a relatively thin thickness. By defining the relationship between CS0, CS1, DOL1, CS2, DOL2, DOL3, and t through a formula, the first, second, and third regions of the first glass can cooperate with each other, thereby improving the first glass's resistance to shattering after general heavy scratches, sharp object compression, and impact defects, and further improving the surface needle drop performance of the first glass.
[0115] The following provides detailed descriptions of Examples 1-3 and Comparative Examples 1-10 for the glass assembly. The preparation method of the glass assembly is as follows:
[0116] 1. According to the automotive glass processing procedure, the soda-lime glass and the aluminosilicate glass are cut and edge-ground, and necessary decorative layers such as ink and silver paste are applied to the soda-lime glass as needed.
[0117] 2. The sodium-calcium silicate glass is hot-bent and physically strengthened according to the mechanical requirements corresponding to the glass loading position, including but not limited to hot strengthening, semi-tempered and fully tempered.
[0118] 3. The aluminosilicate glass is thermally strengthened and bent into a shape that matches the soda-lime glass, and a surface compressive stress in the range of 5MP-15MPa and a stress layer depth DOL3 of ≥0.25t are formed on the surface.
[0119] 4. The aluminosilicate glass obtained in step 3 is strengthened by low-stress ion exchange to have a surface compressive stress in the range of 300MP-500MPa, a DOL2 in the range of 0.035mm-0.055mm, and an inflection point stress CS2 in the range of 5MP-15MPa at the DOL2.
[0120] 5. The aluminosilicate glass obtained in step 4 is subjected to a final surface stress CS0 in the range of 600MP-900MPa, a DOL1 in the range of 0.005mm-0.015mm, and an inflection point stress CS1 in the range of 200MP-300MPa formed at DOL1, thereby obtaining the composite strengthened aluminosilicate glass.
[0121] 6. Using conventional organic intermediate layers as raw materials, including but not limited to PVB, EVA, etc., the physically strengthened soda-lime glass and the composite strengthened aluminosilicate glass are laminated together to obtain the automotive glass.
[0122] Using the door glass as the loading point, soda-lime glass was physically tempered, and Examples 1-3 were prepared according to the aluminosilicate glass strengthening method described in this invention. Additionally, Comparative Examples 1-10 were prepared using conventional aluminosilicate glass strengthening methods and strengthening methods similar to those of this invention but not meeting the composite stress conditions described in this invention. The processing parameters for the examples and comparative examples are shown in Table 1.
[0123] Table 1. Processing parameters for examples and comparative examples.
[0124]
[0125]
[0126] A composite structure of 3.5mm soda-lime glass and 1.1mm aluminosilicate glass was selected. After strengthening the thin inner aluminosilicate glass according to the embodiments and comparative examples, the laminated glass was manufactured while keeping other process conditions unchanged. The needle drop test was used to test the needle drop height on the inner surface. In addition, 1.1mm samples of the embodiments and comparative examples were made according to the three-point bending method specified in GBT 34171, and their three-point bending strength was tested. The stress distribution of each embodiment and comparative example is shown in Table 2, and the technical effect is shown in Table 3.
[0127] Table 2 Stress Distribution of Examples and Comparative Examples
[0128]
[0129] Table 3. Technical Effects of Examples and Comparative Examples
[0130]
[0131]
[0132] As can be seen from Table 3, Examples 1-3, which are prepared according to the preparation method provided in this application and meet the stress requirement range, have the characteristics of high bending strength (bending strength ≥ 450 MPa) and good needle drop performance. They take into account the contradictory mechanical properties of bending strength and crack propagation, so that chemically tempered thin glass can be better applied in automotive glass application scenarios and meet the requirements of safety, reliability and durability.
[0133] As can be seen from the M value and CT value in Examples 1-3 and Comparative Examples 1-10, the M value and CT value are positively correlated in terms of quantity. That is, as the M value increases, the central tensile stress of the glass also increases. In order to avoid the easy propagation of cracks caused by impact on the glass due to excessive CT value, it is necessary to limit the size of the M value to meet the needle drop performance.
[0134] Comparative Examples 1 and 2 are only heat-strengthened. Although the M value is small (the central tensile stress CT value is small) and the needle dropping performance is high, the three-point bending strength is insufficient due to the low surface compressive stress CS0.
[0135] Comparative Example 3 used only a low level of ion exchange to strengthen the glass, resulting in a lower surface compressive stress CS0 and consequently lower three-point bending strength.
[0136] Comparative Example 4, without thermal strengthening of the glass plate, underwent two ion exchange treatments (the first at a lower level and the second at a higher level). It did not have the deep compressive stress layer obtained by thermal strengthening, and the needle could easily penetrate the compressive stress layer, leading to propagation.
[0137] Although Comparative Example 5 employed a high level of thermal strengthening treatment on the glass plate, it only used a low level of ion exchange during the chemical strengthening stage. As a result, not only was the surface compressive stress CS0 low, but the M value was also high, which led to the failure to meet the requirements for three-point bending strength and pin drop performance.
[0138] Comparative Example 6 applied a high level of thermal strengthening treatment to the glass plates. The thermal strengthening resulted in a high compressive stress CS2, which in turn led to a large M value. Specifically, the central tensile stress CT value was large, which could not meet the requirements of the needle drop performance test.
[0139] Comparative Example 7 used a lower level of thermal strengthening treatment on the glass plates and only performed a high level of ion exchange once, which resulted in an increase in DOL1 and thus a larger M value. Specifically, the central tensile stress CT value was larger, which could not meet the requirements of the needle drop performance test.
[0140] Comparative Example 8 used a lower level of thermal strengthening treatment on the glass plates and only performed two high-level ion exchanges, which resulted in an increase in DOL1 and thus a larger M value. Specifically, the central tensile stress CT value was larger, which could not meet the requirements of the needle drop performance test.
[0141] Comparative Example 9 had a lower level of thermal strengthening treatment on the glass plate and only one low level of ion exchange. Its surface compressive stress CS0 was low and could not meet the three-point bending strength requirements.
[0142] Comparative Example 10 glass plates underwent a lower level of thermal strengthening treatment and only two low-level ion exchanges, resulting in a lower surface compressive stress CS0, which could not meet the three-point bending strength requirements.
[0143] The above provides a detailed description of the embodiments provided in this application. This document elucidates and explains the principles and implementation methods of this application. The above description is only intended to help understand the methods and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.
Claims
1. A type of glass, characterized in that, The glass has a first region, a second region, and a third region. The second region is located within the first region, and the third region is located within the second region. The first region, the second region, and the third region all extend from the outer surface of the glass to the center of the glass. The glass satisfies the following conditions: (CS0+CS1)*DOL1+(CS1+CS2)*(DOL2-DOL1)+CS2*(DOL3-DOL2)≤24*t, and CS0≥600MPa, DOL1+DOL2+DOL3≥0.25t; The glass also satisfies the following condition: (CS0-CS1) / DOL1≥2.5*(CS1-CS2) / (DOL2-DOL1); Wherein, CS0 represents the surface compressive stress of the glass, CS1 represents the inflection point stress of the glass between the first and second ion exchange processes, DOL1 represents the inflection point depth of the glass between the first and second ion exchange processes, CS2 represents the inflection point stress of the glass between the thermal strengthening process and the first ion exchange process, DOL2 represents the inflection point depth of the glass between the thermal strengthening process and the first ion exchange process, DOL3 represents the stress depth of the glass during the thermal strengthening process, and t represents the thickness of the glass.
2. The glass as described in claim 1, characterized in that, In the glass, CS0, CS1, and DOL1 satisfy the following conditions: 600MPa≤CS0≤900MPa, 200MPa≤CS1≤300MPa, and 0.005mm≤DOL1≤0.015mm.
3. The glass as described in claim 1, characterized in that, In the glass, CS2 and DOL2 satisfy the following conditions: 5MPa≤CS2≤15MPa, 0.035mm≤DOL2≤0.055mm.
4. The glass as claimed in claim 1, characterized in that, In the glass, DOL3 and t satisfy the following conditions: DOL3≥0.25t, 0.7mm≤t≤1.2mm.
5. The glass as described in claim 1, characterized in that, The central tensile stress CT of the glass satisfies the following condition: CT≤30MPa.
6. The glass as claimed in claim 1, characterized in that, The first region is formed by a thermal intensification process, the second region is formed by a first ion exchange process, and the third region is formed by a second ion exchange process.
7. A method for preparing glass, characterized in that, The preparation method includes: Provide the glass to be processed; The glass to be processed is subjected to a heat strengthening process to obtain a first strengthened glass; The first tempered glass is subjected to a first ion exchange process to obtain the second tempered glass; The second strengthened glass is subjected to a second ion exchange process to obtain the glass as described in any one of claims 1-6; During the heat strengthening process, the glass to be treated is heated to a temperature of T1, and the heated glass is cooled to a pressure of P. T1 and P satisfy the following conditions: 550℃≤T1≤750℃, 50mmWC≤P≤220mmWC. During the first ion exchange process, the first tempered glass satisfies one of the following: A mixed salt bath of potassium nitrate and sodium nitrate is used; wherein the mass ratio of potassium nitrate to sodium nitrate is (80-95):(5-20), and the temperature of the first ion exchange process is T2 and the time is C1, wherein T2 and C1 satisfy the following conditions: 380℃≤T2≤450℃, 60min≤C1≤150min; A potassium nitrate salt bath is used; wherein, the proportion of potassium nitrate in the salt is not less than 95%, and the first ion exchange process includes a daughter ion exchange process and a daughter ion migration process. The temperature of the daughter ion exchange process is T3 and the time is C2, and T3 and C2 satisfy the following conditions: 380℃≤T3≤450℃, 50min≤C2≤100min; the daughter ion migration process is not immersed in the potassium nitrate salt bath, but is completed in air, and the migration temperature is T4 and the migration time is C3, and T4 and C3 satisfy the following conditions: 450℃≤T4≤500℃, 10min≤C3≤60min; An ion exchange barrier layer is formed on the first tempered glass, and a potassium nitrate salt bath is used; wherein, the proportion of potassium nitrate in the salt is not less than 95%, and the temperature of the first ion exchange process is T5 and the time is C4, and T5 and C4 satisfy the following conditions: 380℃≤T5≤450℃, 90min≤C4≤180min; In the second ion exchange process, a potassium nitrate salt bath is used; wherein, the proportion of potassium nitrate in the salt is not less than 95%, and the temperature of the second ion exchange process is T6 and the time is C5, wherein T6 and C5 satisfy the following conditions: 400℃≤T6≤450℃, 120s≤C5≤600s.
8. The preparation method according to claim 7, characterized in that, The step of performing a heat strengthening process on the glass to be treated includes: The surface compressive stress σ1 of the glass to be treated is made to satisfy the following conditions: 5MPa≤σ1≤15MPa, and the values of DOL3 and t in the glass to be treated satisfy: DOL3≥0.25t, 0.7mm≤t≤1.2mm, thus obtaining the first tempered glass.
9. The preparation method according to claim 7, characterized in that, The step of performing the first ion exchange process on the first tempered glass includes: The surface compressive stress σ2 of the first tempered glass is made to satisfy the following conditions: 300MPa≤σ2≤500MPa, and in the first tempered glass, CS2 and DOL2 satisfy the following conditions: 5MPa≤CS2≤15MPa, 0.035mm≤DOL2≤0.055mm, to obtain the second tempered glass.
10. The preparation method according to claim 7, characterized in that, The step of performing a second ion exchange process on the second strengthened glass includes: The surface compressive stress σ3 of the second tempered glass is made to satisfy the following conditions: 600MPa≤σ3≤900MPa, and in the second tempered glass, CS1 and DOL1 satisfy the following conditions: 200MPa≤CS1≤300MPa, 0.005mm≤DOL1≤0.015mm, thus obtaining the glass.
11. A glass assembly, characterized in that, The glass assembly includes an intermediate layer, a first glass, and a second glass, wherein the first glass is the glass as described in any one of claims 1-6, and the first glass and the second glass are respectively disposed on opposite sides of the intermediate layer.
12. The glass assembly as claimed in claim 11, characterized in that, When a needle with a diameter of 4.6 mm, a length of 25 mm, a total mass of 3.2 g, and a diamond tip angle of 120° is dropped onto the surface of the first glass away from the intermediate layer, the needle height H1 on the surface of the first glass away from the intermediate layer satisfies the following condition: H1 ≥ 200 mm.
13. The glass assembly as claimed in claim 11, characterized in that, When a needle with a diameter of 4.6 mm, a length of 25 mm, a total mass of 3.2 g, and a diamond tip angle of 120° is dropped onto the surface of the second glass away from the intermediate layer, the needle height H2 away from the surface of the second glass away from the intermediate layer satisfies the following condition: H2 ≥ 300 mm.
14. A vehicle, characterized in that, The vehicle includes a body and a glass assembly as described in any one of claims 11-13, the glass assembly being mounted on the body; wherein, in the glass assembly, a first glass is closer to the interior space of the body than a second glass.