Ceramic glass composite with strong impact resistance and preparation method thereof, electronic device

Abstract

The application discloses a ceramic glass composite with strong impact resistance, a preparation method thereof and electronic equipment. The composite is composed of a ceramic layer, a glass layer and a bonding layer, and has a bending strength of 1000 MPa or above, a drop ball performance of not less than 37 cm or a point pressure value of not less than 110 N.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of new materials, and particularly relates to a ceramic glass composite with strong impact resistance and a preparation method thereof and an electronic device. BACKGROUND

[0002] With the rapid development of the smart phone industry, consumers' requirements for the performance of the back plate of the phone are increasing, and the phone back plate is not only required to have a good appearance, but also to have excellent mechanical strength, impact resistance and lightweight characteristics. The phone back plate materials on the market at present mainly include metal, glass, ceramic and composite materials. Among them, ceramic materials have the advantages of high strength, high hardness and wear resistance, but have the problems of brittleness, poor impact resistance and high processing difficulty; glass materials have high transparency and convenient processing, but have insufficient mechanical strength and are easy to break; single material is difficult to meet the stringent requirements of the phone back plate on comprehensive performance.

[0003] To solve the above problems, a composite structure of ceramic and glass appears in the related art, for example, the patent with the publication number CN208410950U discloses an impact-resistant shell material and a digital product shell. The impact-resistant shell material comprises a surface layer and an energy-absorbing layer connected to the surface layer; the surface layer is made of ceramic, microcrystalline glass or ordinary glass; the energy-absorbing layer is made of high modulus material; the digital product shell comprises a surface layer and an energy-absorbing layer connected to the surface layer; the surface layer is made of ceramic, microcrystalline glass or ordinary glass; the energy-absorbing layer is made of high modulus material. The impact-resistant shell material disclosed in the utility model can provide surface effect and certain impact resistance, the energy-absorbing layer adopts high modulus and high toughness material, which can absorb impact energy and protect the surface layer, and improve the impact resistance of the overall structure. The existing composite structure generally has the defects of poor adhesion stability, insufficient control precision of the thickness of the glue layer, and excessive overall thickness after compounding, which leads to limited improvement of the impact resistance of the composite and cannot fully meet the use requirements of the phone back plate. Therefore, it has become a technical problem to be solved in the current field to develop a ceramic glass composite with ultrathin thickness and significantly improved impact resistance and a phone back plate thereof. SUMMARY

[0004] In order to overcome the deficiencies in the prior art, the present application provides a ceramic glass composite with ultrathin thickness and strong impact resistance, and the specific technical solutions are as follows:

[0005] A ceramic glass composite with high impact resistance, comprising a ceramic layer, a glass layer and an adhesive layer, the ceramic layer and the glass layer being adhered by the adhesive layer, the ceramic glass composite having a thickness of 0.3-0.6mm, a bending strength of 1000MPa or more, and / or a drop ball performance of not less than 37cm, and / or a point pressure value of not less than 110N. In some embodiments, the ceramic glass composite has a thickness of 0.3mm or 0.31mm or 0.32mm or 0.33mm or 0.34mm or 0.35mm or 0.36mm or 0.37mm or 0.38mm or 0.39mm or 0.40mm or 0.41mm or 0.42mm or 0.43mm or 0.44mm or 0.45mm or 0.46mm or 0.47mm or 0.48mm or 0.49mm or 0.50mm or 0.51mm or 0.52mm or 0.53mm or 0.54mm or 0.55mm or 0.56mm or 0.57mm or 0.58mm or 0.59mm or 0.60mm or a value within a range defined by any two of the above specific numerical values as endpoints; a bending strength of 1000MPa or 1030MPa or 1050MPa or 1100MPa or 1130MPa or 1150MPa or a value within a range defined by any two of the above specific numerical values as endpoints; a drop ball performance of 37cm or 38cm or 39cm or 40cm or 41cm or 42cm or 43cm or 44cm or 45cm or a value within a range defined by any two of the above specific numerical values as endpoints; a point pressure value of 110N or 115N or 120N or 125N or 130N or a value within a range defined by any two of the above specific numerical values as endpoints; further, a Young's modulus of 380-420GPa, and in some embodiments, a Young's modulus of 380GPa or 385GPa or 390GPa or 395GPa or 400GPa or 405GPa or 410GPa or 415GPa or 420GPa or a value within a range defined by any two of the above specific numerical values as endpoints.

[0006] The ceramic layer has a thickness of 0.09-0.30 mm, in some embodiments, the ceramic layer has a thickness of 0.09 mm or 0.1 mm or 0.11 mm or 0.12 mm or 0.13 mm or 0.14 mm or 0.15 mm or 0.16 mm or 0.17 mm or 0.18 mm or 0.19 mm or 0.2 mm or 0.21 mm or 0.22 mm or 0.23 mm or 0.24 mm or 0.25 mm or 0.26 mm or 0.27 mm or 0.28 mm or 0.29 mm or 0.30 mm or a value within a range of values having any two of the aforementioned specific numerical values as endpoints. The glass layer has a thickness of 0.15-0.30 mm, in some embodiments, the glass layer has a thickness of 0.15 mm or 0.16 mm or 0.17 mm or 0.18 mm or 0.19 mm or 0.2 mm or 0.21 mm or 0.22 mm or 0.23 mm or 0.24 mm or 0.25 mm or 0.26 mm or 0.27 mm or 0.28 mm or 0.29 mm or 0.30 mm or a value within a range of values having any two of the aforementioned specific numerical values as endpoints. The adhesive layer has a thickness of 0.005-0.05 mm, in some embodiments, the adhesive layer has a thickness of 0.005 mm or 0.01 mm or 0.02 mm or 0.03 mm or 0.04 mm or 0.05 mm or a value within a range of values having any two of the aforementioned specific numerical values as endpoints.

[0007] Preferably, the ratio of the thickness of the ceramic layer to the thickness of the glass layer in the composite is 0.4-1.4. Preferably, it is 0.41-1.36; more preferably, it is 0.55-1.14. In some embodiments, the ratio of the thickness of the ceramic layer to the thickness of the glass layer in the composite is 0.4 or 0.41 or 0.42 or 0.43 or 0.44 or 0.45 or 0.46 or 0.47 or 0.48 or 0.49 or 0.5 or 0.51 or 0.52 or 0.53 or 0.54 or 0.55 or 0.56 or 0.57 or 0.58 or 0.59 or 0.6 or 0.61 or 0.62 or 0.63 or 0.64 or 0.65 or 0.66 or 0.67 or 0.68 or 0.69 or 0.7 or 0.71 or 0.72 or 0.73 or 0.74 or 0.75 or 0.76 or 0.77 or 0.78 or 0.79 or 0.8 or 0.81 or 0.82 or 0.83 or 0.84 or 0.85 or 0.86 or 0.87 or 0.88 or 0.89 or 0.9 or 0.91 or 0.92 or 0.93 or 0.94 or 0.95 or 0.96 or 0.97 or 0.98 or 0.99 or 1 or 1.01 or 1.02 or 1.03 or 1.04 or 1.05 or 1.06 or 1.07 or 1.08 or 1.09 or 1.1 or 1.11 or 1.12 or 1.13 or 1.14 or 1.15 or 1.16 or 1.17 or 1.18 or 1.19 or 1.2 or 1.21 or 1.22 or 1.23 or 1.24 or 1.25 or 1.26 or 1.27 or 1.28 or 1.29 or 1.3 or 1.31 or 1.32 or 1.33 or 1.34 or 1.35 or 1.36 or 1.37 or 1.38 or 1.39 or 1.4 or a value within a range defined by any two of the above specifically stated values as endpoints.

[0008] The ceramic layer is a zirconia ceramic or a silicon nitride ceramic; the glass layer is a microcrystalline glass or a chemically strengthened ordinary glass (an ordinary glass that can be strengthened in the prior art, using a general-purpose chemical strengthening process); and the adhesive layer is an epoxy resin-based layer or an acrylic resin-based layer. Further, the microcrystalline glass is a lithium disilicate microcrystalline glass or a magnesium-aluminum-silicon-based microcrystalline glass or a LAS-based microcrystalline glass.

[0009] A method for preparing a ceramic-glass composite with high impact resistance as described above, comprising the following steps:

[0010] Step 1: bonding a ceramic layer with a thickness of 0.25-0.45 mm and a glass layer with a thickness of 0.15-0.30 mm through an adhesive layer with a thickness of 0.005-0.05 mm to obtain an initial composite;

[0011] Step 2: subjecting the initial composite obtained in Step 1 to a curing process, which is UV curing or / and thermal curing or / thermal pressure curing.

[0012] Step 3: thinning treatment is performed on the composite obtained in step 2, the thickness of the ceramic layer is thinned to 0.09-0.30 mm, and the final product is obtained.

[0013] The preparation process of the adhesive layer in the step 1 is a slot coating process or a doctor blade coating process or a dispensing coating process. Preferably, when the slot coating process is selected, the coating speed is 30-50 mm / s, the coating pressure is 0.1-0.3 MPa, and the coating gap is 0.01-0.1 mm, so as to ensure the uniformity of the glue layer; when the doctor blade coating is selected, the doctor blade angle is 30°-60°, the coating speed is 20-40 mm / s, and the doctor blade gap is 0.005-0.05 mm, so as to accurately control the thickness of the glue layer; when the dispensing coating process is selected, the dispensing pressure is 0.2-0.4 MPa, the dispensing speed is 15-30 mm / s, and the dispensing spacing is 2-5 mm, and the uniform coverage of the glue layer is realized through subsequent lamination and compaction.

[0014] The specific process of UV curing in the step 2 is to use ultraviolet rays with a wavelength of 320-390 nm for irradiation, the irradiation intensity is 1000-4000 mJ / cm², and the irradiation time is 20-60 s; the curing temperature of heat pressing curing is 60-100°C, the curing pressure is 0.5-1.5 MPa, and the curing time is 1-24 h; the curing temperature of heat curing is 60-100°C, and the curing time is 1-24 h.

[0015] The specific process of the thinning treatment in the step 3 is: rough grinding first and then fine grinding; rough grinding selects a 320-600 mesh diamond grinding wheel, the spindle speed is 3000-5000 rpm, the feed speed is 5-10 μm / s, the downward pressure is 20-50 N, and the excess thickness of the ceramic layer is removed; fine grinding selects a 2000-3000 mesh resin bond diamond grinding wheel, the spindle speed is 8000-12000 rpm, the feed speed is 0.5-1 μm / s, the downward pressure is 5-15 N, and the flatness of the outer surface of the ceramic layer is improved, so that the final roughness Ra of the outer surface of the ceramic layer is ≤0.01 μm.

[0016] An electronic device contains the aforementioned ceramic glass composite with strong impact resistance.

[0017] The second technical solution provided by the application is a ceramic glass composite with strong impact resistance, which is composed of a ceramic layer, a glass layer and an adhesive layer, the thickness ratio of the ceramic layer to the glass layer is 0.4-1.4, the thickness of the adhesive layer accounts for 1-11.5% of the total thickness of the composite, and the bending strength of the composite is 1000 MPa or more, or / and the drop ball performance is not less than 37 cm, or / and the point pressure value is not less than 110 N.

[0018] Further, the thickness of the ceramic glass composite is 0.3-0.6 mm.

[0019] Preferably, the ratio of the thickness of the ceramic layer to the thickness of the glass layer in the composite is 0.4-1.4. Preferably, 0.41-1.36; more preferably, 0.55-1.14. In some embodiments, the ratio of the thickness of the ceramic layer to the thickness of the glass layer in the composite is 0.4 or 0.41 or 0.42 or 0.43 or 0.44 or 0.45 or 0.46 or 0.47 or 0.48 or 0.49 or 0.5 or 0.51 or 0.52 or 0.53 or 0.54 or 0.55 or 0.56 or 0.57 or 0.58 or 0.59 or 0.6 or 0.61 or 0.62 or 0.63 or 0.64 or 0.65 or 0.66 or 0.67 or 0.68 or 0.69 or 0.7 or 0.71 or 0.72 or 0.73 or 0.74 or 0.75 or 0.76 or 0.77 or 0.78 or 0.79 or 0.8 or 0.81 or 0.82 or 0.83 or 0.84 or 0.85 or 0.86 or 0.87 or 0.88 or 0.89 or 0.9 or 0.91 or 0.92 or 0.93 or 0.94 or 0.95 or 0.96 or 0.97 or 0.98 or 0.99 or 1 or 1.01 or 1.02 or 1.03 or 1.04 or 1.05 or 1.06 or 1.07 or 1.08 or 1.09 or 1.1 or 1.11 or 1.12 or 1.13 or 1.14 or 1.15 or 1.16 or 1.17 or 1.18 or 1.19 or 1.2 or 1.21 or 1.22 or 1.23 or 1.24 or 1.25 or 1.26 or 1.27 or 1.28 or 1.29 or 1.3 or 1.31 or 1.32 or 1.33 or 1.34 or 1.35 or 1.36 or 1.37 or 1.38 or 1.39 or 1.4 or a value within a range of values between any of the above-enumerated values, as an endpoint.

[0020] The thickness of the ceramic layer is 27-56% of the total thickness of the composite. In some embodiments, the thickness of the ceramic layer is 27% or 28% or 29% or 30% or 31% or 32% or 33% or 34% or 35% or 36% or 37% or 38% or 39% or 40% or 41% or 42% or 43% or 44% or 45% or 46% or 47% or 48% or 49% or 50% or 51% or 52% or 53% or 54% or 55% or 56% or a value within a range of values between any of the above-enumerated values, as an endpoint.

[0021] The thickness of the glass layer is 40-67% of the total thickness of the composite, in some embodiments, the thickness of the glass layer is 40% or 41% or 42% or 43% or 44% or 45% or 46% or 47% or 48% or 49% or 50% or 51% or 52% or 53% or 54% or 55% or 56% or 57% or 58% or 59% or 60% or 61% or 62% or 63% or 64% or 65% or 66% or 67% or a value within a range defined by any two of the above-mentioned specific numerical values as endpoints.

[0022] The thickness of the adhesive layer is 1-11.5% of the total thickness of the composite, in some embodiments, the thickness of the adhesive layer is 1% or 1.2% or 2% or 3% or 4% or 5% or 6% or 7% or 8% or 9% or 10% or 11% or 11.1% or 11.5% or a value within a range defined by any two of the above-mentioned specific numerical values as endpoints.

[0023] A method for preparing the aforementioned ceramic glass composite with strong impact resistance, comprising the following steps:

[0024] Step 1: bonding the ceramic layer and the glass layer in a thickness ratio of 1.13-2.04 ceramic layer through the adhesive layer to obtain an initial composite, preferably, in this step, the thickness of the adhesive layer is 0.8-8.10% of the total thickness of the composite, more preferably, in this step, the thickness of the ceramic layer is preferably 0.25-0.45 mm, the thickness of the glass layer is preferably 0.15-0.30 mm, and the thickness of the adhesive layer is preferably 0.005-0.05 mm;

[0025] Step 2: curing the initial composite obtained in step 1, and the curing process is UV curing or / and thermal curing or / thermal pressure curing;

[0026] Step 3: thinning the composite obtained in step 2, so that the thickness of the ceramic layer is 27-56% of the total thickness of the composite, and the thickness ratio of the ceramic layer to the glass layer is 0.4-1.4, to obtain the final product.

[0027] The preparation process of the adhesive layer in step 1 is a slot coating process or a doctor blade coating process or a dispensing coating process. Preferably, when the slot coating process is selected, the coating speed is 30-50 mm / s, the coating pressure is 0.1-0.3 MPa, and the coating gap is 0.01-0.1 mm to ensure the uniformity of the adhesive layer; when the doctor blade coating is selected, the doctor blade angle is 30°-60°, the coating speed is 20-40 mm / s, and the doctor blade gap is 0.005-0.05 mm to precisely control the thickness of the adhesive layer; when the dispensing coating process is selected, the dispensing pressure is 0.2-0.4 MPa, the dispensing speed is 15-30 mm / s, and the dispensing spacing is 2-5 mm, and the uniformity of the adhesive layer is achieved through subsequent lamination and compaction.

[0028] The specific process of UV curing in step 2 is to irradiate ultraviolet light with a wavelength of 320-390 nm, an irradiation intensity of 1000-4000 mJ / cm², and an irradiation time of 20-60 s; the curing temperature of heat pressing is 60-100 ℃, the curing pressure is 0.5-1.5 MPa, and the curing time is 1-24 h.

[0029] The specific process of thinning treatment in step 3 is: rough grinding and then fine grinding; rough grinding selects a 320-600 mesh diamond grinding wheel, the spindle speed is 3000-5000 rpm, the feed speed is 5-10 μm / s, the downward pressure is 20-50 N, and the excess thickness of the ceramic layer is removed; fine grinding selects a 2000-3000 mesh resin bond diamond grinding wheel, the spindle speed is 8000-12000 rpm, the feed speed is 0.5-1 μm / s, the downward pressure is 5-15 N, and the flatness of the outer surface of the ceramic layer is improved, so that the final roughness Ra of the outer surface of the ceramic is ≤0.01 μm.

[0030] An electronic device containing the aforementioned ceramic glass composite with strong impact resistance.

[0031] The present application realizes: 1. Stress field optimization: the surface compressive stress formed after thinning can passivate or inhibit the newly generated micro subsurface cracks during the thinning process, even if new defects are introduced, the risk of expansion is significantly reduced; 2. Interface stress relief: redistribution of residual stress reduces harmful tensile stress or peeling stress at the interface, so that the interface bonding potential can be fully utilized, and the overall carrying capacity is improved; 3. Surface defect elimination: thinning directly removes or reduces large-size defects on the surface, avoiding the failure path of crack initiation from the surface and expansion to the interface, thereby protecting the interface integrity.

[0032] The composite undergoes the following processes from compounding to thinning: 1. Initial state: there is a residual stress field in the composite that is not necessarily optimal. There are large size and randomly distributed microcracks and scratches on the surface of the composite, which are introduced during manufacturing and handling. These large size defects are the main limiting factors of the strength; 2. During thinning, the material is removed layer by layer. In this dynamic process: the original surface layer is physically removed, and new but smaller and more controllable processing defects are introduced on the newly formed surface. At the same time, a strong surface compression stress layer is formed, and the removal of material breaks the original mechanical balance; 3. Finally, a new equilibrium state is reached. In this new state, the composite has threefold optimization: 1) Stress optimization: the surface is covered with a layer of processing-induced, uniformly distributed and controllable protective compression stress. At the same time, the harmful tensile stress peaks in the interior may be alleviated due to global reconstruction. 2) Defect optimization: the maximum defect size that controls the strength of the material is reduced, and the strength short board is made up. 3) Interface optimization: the stress environment of the interface region is improved, and the microstructure gradient near the interface may play a more significant role in the new geometric configuration. The synergistic effect of the threefold optimization makes the thinned composite thinner in macroscopic size, but stronger in micro load-bearing capacity and reliability.

[0033] Of course, the precise design of the initial thickness of each layer is the fundamental prerequisite for achieving the thinning enhancement phenomenon. Different initial layer thickness ratios will determine the size, distribution pattern and total strain energy of the initial residual stress field. This initial state determines the basis for whether the thinning process is optimized or deteriorated. The present scheme proposes and verifies the optimal window of the thickness ratio of ceramic layer to glass layer, the proportion of adhesive layer and other parameters. In the strength-toughness-thickness three-dimensional index system, a best window is explored, which realizes the super-linear superposition of performance at the limit scale; the brittleness of ceramic and glass is compensated and transformed by the plasticity of the adhesive layer; the final performance far exceeds that of a single material at the same thickness, and also exceeds the expected performance of linear superposition of the two.

[0034] In addition, the thinning amount (i.e. the removed thickness) itself is also a crucial process parameter. If the thinning is insufficient, it may not completely remove the original harmful defect layer, and it may not form a deep enough surface compression stress layer; if the thinning is excessive, it may weaken the total load-bearing cross section of the structure, or it may reach the area of internal harmful tensile stress concentration, thereby leading to performance degradation. Therefore, there is an optimal thinning thickness that can maximize the above-mentioned multiple positive effects.

[0035] The mobile phone back plate prepared from the ultra-thin ceramic glass composite with high impact resistance has the following beneficial effects: 1. The bending strength can reach 1150 MPa, the ball drop height is not less than 37 cm, and the point pressure performance is not less than 110 N; 2. The targeted thinning process effectively reduces the constraint of the brittle dominant role of the ceramic layer and the stress concentration at the interface under the premise of ensuring the structural strength, can dissipate more impact energy, and at the same time, reduces the overall weight of the composite, meeting the design requirements of mobile phone lightweight; 3. The glue coating process, curing process and thinning process parameter design of the application are controllable, suitable for industrial batch production, and the selected materials have a wide source and controllable cost, having high practical value; 4. Compared with the back plate made of single ceramic or single glass material, the ultra-thin ceramic glass composite mobile phone back plate of the application has significant improvement in ball drop impact resistance and point pressure bearing performance, and has a longer service life. BRIEF DESCRIPTION OF DRAWINGS

[0036] Figure 1 is a manufacturing and processing process flow diagram of the ceramic glass composite of the application;

[0037] Figure 2 is a physical diagram of the ultra-thin ceramic glass composite of the patent embodiment 1.

[0038] Among them, 1-ceramic layer; 2-adhesive layer; 3-glass layer. DETAILED DESCRIPTION

[0039] Embodiment 1

[0040] The processing process flow as shown in Figure 1 is adopted, step 1: zirconia ceramic with an initial thickness of 0.35 mm is used as the ceramic layer, lithium disilicate glass ceramic with a thickness of 0.22 mm is used as the glass layer, the ceramic layer and the glass layer are bonded through an epoxy resin-based adhesive layer with a thickness of 0.02 mm, the adhesive layer is prepared by slit coating process, and the coating speed is 30~50 mm / s, the coating pressure is 0.1~0.3 MPa, and the coating gap is 0.01~0.1 mm, to ensure the uniformity of the glue layer;

[0041] Step 2: curing treatment, adopting the process of UV curing followed by heat curing, and the specific curing process is as follows: UV curing illumination parameters: wavelength 360 nm, intensity 3600 mJ / cm², illumination 40 s; heat curing parameters: temperature 80℃, time 1h;

[0042] Step 3: thinning treatment, first coarse grinding and then fine grinding; coarse grinding selects 320-600 mesh diamond grinding wheel, spindle speed 3000-5000 rpm, feed speed 5-10 μm / s, down pressure 20-50 N, to remove the excess thickness of the ceramic substrate; fine grinding selects 2000-3000 mesh resin bond diamond grinding wheel, spindle speed 8000-12000 rpm, feed speed 0.5-1 μm / s, down pressure 5-15 N, to improve the flatness of the ceramic surface, so that the final roughness Ra of the ceramic surface is ≤0.01 μm. Finally, the ceramic layer is thinned by 0.17 mm, and the final composite thickness is 0.42 mm.

[0043] The following tests are performed on the final composite: 1. Drop ball performance test: a steel ball with a diameter of 20 mm and a weight of 32 g is dropped freely from a specified height, the carrier is a PVC solid clamp, and whether the composite fixed by the back adhesive (0.2-0.3 mm) appears cracking or cracking is observed, and the highest height without damage is taken as the drop ball performance index; 2. Point pressure performance test: a pressure testing machine is used to perform point pressure at a rate of 1 mm / min, and the pressure value at which the composite appears damaged is recorded as the point pressure performance index; 3. Bending strength test: a four-point bending test method is used, according to the GB / T 6569-2006 standard, the composite is processed into a standard sample of 60 mm x 40 mm x (actual thickness), the lower support point distance is set to 40 mm, the upper support point distance is set to 20 mm, a uniform pressure is applied to the sample by a double pressure head at a loading rate of 10 mm / min, the maximum load at which the sample breaks is recorded, and the bending strength is calculated by the four-point bending strength formula; 4. Young's modulus test: simultaneously combined with the four-point bending test data, the load change and the corresponding sample midpoint deflection change are recorded within the elastic deformation stage, the shear force effect is excluded, and the Young's modulus is derived using the bending theory of elasticity; 5. The above four tests are completed simultaneously to fully characterize the mechanical properties of the composite.

[0044] It is found that the bending strength of the composite in this embodiment is 1130 MPa, the Young's modulus is 420 GPa, the drop ball performance is 45 cm, and the point pressure performance is 130 N.

[0045] Example 2

[0046] Different from example 1 is the thinning thickness in step 3, the ceramic layer thickness in this embodiment is thinned by 0.26 mm, and the final composite total thickness is 0.33 mm; performance test results: bending strength is 1020 MPa, Young's modulus is 385 GPa, drop ball performance is 38 cm, and point pressure performance is 118 N.

[0047] Example 3

[0048] Different from example 1, the thickness reduction in step 3, the ceramic layer thickness is reduced by 0.23mm in this example, and the final composite total thickness is 0.36mm; performance test results: bending strength is 1060MPa, Young's modulus is 405GPa, drop ball performance is 41cm, and point pressure performance is 122N.

[0049] Example 4

[0050] Different from example 1, the thickness reduction in step 3, the ceramic layer thickness is reduced by 0.20mm in this example, and the final composite total thickness is 0.39mm; performance test results: bending strength is 1100MPa, Young's modulus is 415GPa, drop ball performance is 43cm, and point pressure performance is 127N.

[0051] Example 5

[0052] Different from example 1, the thickness reduction in step 3, the ceramic layer thickness is reduced by 0.13mm in this example, and the final composite total thickness is 0.46mm; performance test results: bending strength is 1050MPa, Young's modulus is 410GPa, drop ball performance is 42cm, and point pressure performance is 125N.

[0053] Example 6

[0054] Different from example 1, the thickness reduction in step 3, the ceramic layer thickness is reduced by 0.10mm in this example, and the final composite total thickness is 0.49mm; performance test results: bending strength is 1030MPa, Young's modulus is 400GPa, drop ball performance is 40cm, and point pressure performance is 120N.

[0055] Example 7

[0056] Different from example 1, the thickness reduction in step 3, the ceramic layer thickness is reduced by 0.05mm in this example, and the final composite total thickness is 0.54mm; performance test results: bending strength is 1000MPa, Young's modulus is 380GPa, drop ball performance is 37cm, and point pressure performance is 116N.

[0057] Comparative example 1

[0058] Different from example 1, step 3 is not performed, and the final composite total thickness is 0.59mm in this example; performance test results: bending strength is 950MPa, Young's modulus is 330GPa, drop ball performance is 32cm, and point pressure performance is 108N.

[0059] Comparative example 2

[0060] In the present comparative example, there is only zirconia ceramic with the same material as in Example 1 with a thickness of 0.59 mm, and the performance test results are: bending strength of 920 MPa, Young's modulus of 300 GPa, ball drop performance of 29 cm, and point pressure performance of 100 N.

[0061] Comparative Example 3

[0062] In the present comparative example, there is only glass-ceramic with the same material as in Example 1 with a thickness of 0.59 mm, and the performance test results are: bending strength of 890 MPa, Young's modulus of 280 GPa, ball drop performance of 26 cm, and point pressure performance of 90 N.

[0063] The composition and performance data of Examples 1-7 and Comparative Examples 1-3 are shown in Tables 1-1 and 1-2, and the thickness relationship between the layers in Examples 1-7 is shown in Table 1-3. In which S1 represents Example 1; S2 represents Example 2, and so on; D1 represents Comparative Example 1, D2 represents Comparative Example 2, and so on.

[0064] Table 1-1

[0065]

[0066] Table 1-2

[0067]

[0068] Table 1-3

[0069]

[0070] From Comparative Examples 1-3, it can be seen that the performance of the composite after compounding is better than that of a single glass layer or ceramic layer; further, from Examples 1-7 and Comparative Example 1, when the ceramic layer thickness is reduced from 0 mm (no reduction) to 0.17 mm, the total thickness of the composite is reduced from 0.59 mm to 0.42 mm, the bending strength is increased from 950 MPa to 1130 MPa, the Young's modulus is increased from 330 GPa to 420 GPa, the ball drop performance is increased from 32 cm to 45 cm, and the point pressure performance is increased from 108 N to 130 N, and the mechanical properties are significantly optimized; when the ceramic layer thickness is further increased to 0.26 mm, the total thickness of the composite is reduced to 0.33 mm, but the bending strength, Young's modulus and impact resistance are all significantly decreased, the ball drop performance is only 38 cm, and the point pressure performance is 118 N. The applicant believes that a moderate reduction in the ceramic layer can reduce the original defects in the ceramic, reduce stress concentration, and at the same time optimize the modulus matching of the ceramic and glass, and improve the synergistic load bearing capacity of the composite structure; but excessive reduction will weaken the supporting effect of the ceramic layer, and cannot fully play the high strength advantage, thereby affecting the overall performance of the composite. Therefore, when the ceramic layer thickness is controlled to be 0.17-0.20 mm, the composite can obtain the best overall performance, and the total thickness is 0.39-0.42 mm, which meets the dual requirements of light weight and high performance of the mobile phone back plate.

[0071] At the same time, this method is also suitable for ordinary glass, as shown in Example 8 and Comparative Examples 4-5.

[0072] Example 8

[0073] Different from Example 1, the chemical strengthened ordinary aluminosilicate glass is used in Step 1 of this embodiment, and the total thickness of the final composite is 0.42 mm; the performance test results are: bending strength is 1035 MPa, Young's modulus is 395 GPa, ball drop performance is 40 cm, and point pressure performance is 118 N.

[0074] Comparative Example 4

[0075] Different from Comparative Example 1, the same chemical strengthened ordinary glass as in Example 8 is used in this comparative example, and no thinning treatment is performed, and the thickness is 0.59 mm; the performance test results are: bending strength is 920 MPa, Young's modulus is 315 GPa, ball drop performance is 30 cm, and point pressure performance is 102 N.

[0076] Comparative Example 5

[0077] In this comparative example, there is only a chemical strengthened ordinary glass with a thickness of 0.59 mm, and the performance test results are: bending strength is 850 MPa, Young's modulus is 215 GPa, ball drop performance is 20 cm, and point pressure performance is 82 N.

[0078] The composition and performance data of Example 8 and Comparative Examples 4-5 are shown in Table 2-1 and Table 2-2.

[0079] Table 2-1

[0080]

[0081] Table 2-2

[0082]

[0083] From Example 8, Comparative Examples 4 and 5, it can be seen that for chemically strengthened ordinary glass, the mechanical properties are improved after compounding with a ceramic layer, and after using the product structure and process of the present application, the mechanical properties are further improved. Compared with Comparative Example 1, the performance of the chemically strengthened ordinary glass-ceramic composite prepared by the method of the present application is better than that of the microcrystalline glass-ceramic composite without thinning treatment.

[0084] Further, the applicant has also studied the initial thickness of the ceramic layer in step 1 of the method of the present application.

[0085] Example 9

[0086] Different from Example 1, the initial thickness of the ceramic layer is 0.25 mm, and the total thickness of the final composite is 0.32 mm; the performance test results are: bending strength 1035 MPa, Young's modulus 405 GPa, ball drop performance 40 cm, and point pressure performance 120 N.

[0087] Example 10

[0088] Different from Example 1, the initial thickness of the ceramic layer is 0.30 mm, and the total thickness of the final composite is 0.37 mm; the performance test results are: bending strength 1110 MPa, Young's modulus 415 GPa, ball drop performance 43 cm, and point pressure performance 128 N.

[0089] Example 11

[0090] Different from Example 1, the initial thickness of the ceramic layer is 0.40 mm, and the total thickness of the final composite is 0.47 mm; the performance test results are: bending strength 1080 MPa, Young's modulus 41 GPa, ball drop performance 42 cm, and point pressure performance 125 N.

[0091] Example 12

[0092] Different from Example 1, the initial thickness of the ceramic layer is 0.45 mm, and the total thickness of the final composite is 0.52 mm; the performance test results are: bending strength 1025 MPa, Young's modulus 395 GPa, ball drop performance 39 cm, and point pressure performance 120 N.

[0093] The composition and performance data of Examples 9-12 are shown in Table 3-1 and Table 3-2.

[0094] Table 3-1

[0095]

[0096] Table 3-2

[0097]

[0098] From Examples 1, 9-12, it can be seen that when the glass layer thickness is 0.22 mm, the performance is optimal when the initial thickness of the ceramic layer is 0.35 mm, but in the range of 0.25-0.45 mm, it can also meet the use requirements. Further, the applicant has also studied the thickness of the glass layer in step 1 in the method of the application.

[0099] Example 13

[0100] Different from Example 1, the thickness of the glass-ceramic layer is 0.12 mm, and the total thickness of the final composite is 0.32 mm; the performance test results are: the bending strength is 965 MPa, the Young's modulus is 325 GPa, the drop ball performance is 33 cm, and the point pressure performance is 105 N.

[0101] Example 14

[0102] Different from Example 1, the thickness of the glass-ceramic layer is 0.16 mm, and the total thickness of the final composite is 0.36 mm; the performance test results are: the bending strength is 1025 MPa, the Young's modulus is 395 GPa, the drop ball performance is 40 cm, and the point pressure performance is 115 N.

[0103] Example 15

[0104] Different from Example 1, the thickness of the glass-ceramic layer is 0.30 mm, and the total thickness of the final composite is 0.50 mm; the performance test results are: the bending strength is 995 MPa, the Young's modulus is 380 GPa, the drop ball performance is 38 cm, and the point pressure performance is 110 N.

[0105] Example 16

[0106] Different from Example 1, the thickness of the glass-ceramic layer is 0.40 mm, and the total thickness of the final composite is 0.55 mm; the performance test results are: the bending strength is 960 MPa, the Young's modulus is 355 GPa, the drop ball performance is 35 cm, and the point pressure performance is 108 N.

[0107] Example 17

[0108] The thickness of the glass layer is 0.40 mm, and the total thickness of the final composite is 0.60 mm; the performance test results are: the bending strength is 940 MPa, the Young's modulus is 320 GPa, the drop ball performance is 32 cm, and the point pressure performance is 105 N.

[0109] The composition and performance data of examples 13-17 are shown in Tables 4-1 and 4-2.

[0110] Table 4-1

[0111]

[0112] Table 4-2

[0113]

[0114] As can be seen from examples 1, 13-17, when the initial thickness of the ceramic layer is 0.35 mm, as the thickness of the glass layer increases from 0.12 mm to 0.40 mm, the total thickness of the thinned composite increases from 0.32 mm to 0.62 mm, and each performance first increases and then decreases, and reaches a peak when the glass thickness is 0.22 mm. The reason is that when the glass thickness is too thin (≤0.12 mm), the toughness is insufficient and cannot buffer the impact; when the glass thickness is too thick (≥0.35 mm), the glass modulus is lower than the ceramic, which will reduce the overall rigidity of the composite structure, and at the same time increase the weight of the composite, which does not meet the lightweight demand of the mobile phone backboard. Therefore, the thickness of the glass layer in the present application is 0.15-0.30 mm, and further preferably 0.16-0.30 mm.

[0115] Further, the applicant has also studied the thickness of the adhesive layer in step 1 of the method of the present application.

[0116] Example 18

[0117] The thickness of the adhesive layer is 0.005 mm, the thickness of the final composite is 0.405 mm, and the performance test results are: the bending strength is 1010 MPa, the Young's modulus is 390 GPa, the drop ball performance is 38 cm, and the point pressure performance is 116 N.

[0118] Example 19

[0119] The thickness of the adhesive layer is 0.01 mm, the thickness of the final composite is 0.41 mm, and the performance test results are: the bending strength is 1035 MPa, the Young's modulus is 405 GPa, the drop ball performance is 42 cm, and the point pressure performance is 125 N.

[0120] Example 20

[0121] The thickness of the adhesive layer is 0.03 mm, the thickness of the final composite is 0.43 mm, and the performance test results are: bending strength of 1020 MPa, Young's modulus of 400 GPa, drop ball performance of 40 cm, and point pressure performance of 118 N.

[0122] Example 21

[0123] The thickness of the adhesive layer is 0.04 mm, the thickness of the final composite is 0.44 mm, and the performance test results are: bending strength of 1000 MPa, Young's modulus of 380 GPa, drop ball performance of 37 cm, and point pressure performance of 115 N.

[0124] Example 22

[0125] The thickness of the adhesive layer is 0.05 mm, the thickness of the final composite is 0.45 mm, and the performance test results are: bending strength of 975 MPa, Young's modulus of 350 GPa, drop ball performance of 35 cm, and point pressure performance of 110 N.

[0126] The composition and performance data of Examples 18-22 are shown in Tables 5-1 and 5-2.

[0127] Table 5-1

[0128]

[0129] Table 5-2

[0130]

[0131] As can be seen from Examples 1, 18-22, the thickness of the adhesive layer has a key influence on the interfacial bonding strength and overall mechanical properties of the composite. When the thickness of the adhesive layer is 0.02 mm, the bending strength, Young's modulus, drop ball performance, and point pressure performance of the composite are all optimal. When the thickness of the adhesive layer is too thick (e.g., 0.05 mm), internal pores and residual stress are easily generated during the curing process of the adhesive, and the modulus of the adhesive layer itself is lower than that of the ceramic and glass, which can weaken the overall rigidity of the composite structure, resulting in a decrease in bending strength and impact resistance.

[0132] Example 23

[0133] In Example 1, the adhesive layer is obtained by using a doctor blade coating method in Step 1. During the doctor blade coating, the doctor blade angle is 30°-60°, the coating speed is 20-40 mm / s, and the doctor blade gap is 0.005-0.05 mm. The performance of the composite obtained by precisely controlling the thickness of the adhesive layer is: bending strength of 1025 MPa, Young's modulus of 390 GPa, drop ball performance of 41 cm, and point pressure performance of 123 N.

[0134] Example 24

[0135] Different from example 1, the adhesive layer in step 1 is obtained by dispensing coating, the dispensing pressure is 0.2-0.4 MPa, the dispensing speed is 15-30 mm / s, the dispensing interval is 2-5 mm, and the uniform coverage of the adhesive layer is achieved by subsequent lamination and compaction. The performance of the composite obtained is: the bending strength is 970 MPa, the Young's modulus is 345 GPa, the ball drop performance is 35 cm, and the point pressure performance is 113 N.

[0136] Example 25

[0137] Different from example 1, the adhesive layer in step 1 is polyurethane-based, and the performance of the composite obtained is: the bending strength is 1020 MPa, the Young's modulus is 390 GPa, the ball drop performance is 40 cm, and the point pressure performance is 110 N.

[0138] Example 26

[0139] Different from example 1, the adhesive layer in step 1 is acrylic resin-based, and the performance of the composite obtained is: the bending strength is 1005 MPa, the Young's modulus is 365 GPa, the ball drop performance is 37 cm, and the point pressure performance is 105 N.

[0140] Example 27

[0141] Different from example 1, the ceramic layer in step 1 is a silicon nitride ceramic layer, and the performance of the composite obtained is: the bending strength is 1090 MPa, the Young's modulus is 410 GPa, the ball drop performance is 43 cm, and the point pressure performance is 126 N.

[0142] Example 28

[0143] Different from example 9, the ceramic layer in step 1 is a silicon nitride ceramic layer, and the performance of the composite obtained is: the bending strength is 1015 MPa, the Young's modulus is 390 GPa, the ball drop performance is 39 cm, and the point pressure performance is 120 N.

[0144] Comparative example 6

[0145] This comparative example only contains a silicon nitride ceramic, and the thickness of the silicon nitride ceramic is 0.59 mm, the bending strength is 880 MPa, the Young's modulus is 260 GPa, the ball drop performance is 25 cm, and the point pressure performance is 92 N.

[0146] Example 29

[0147] Different from example 1, only UV curing is used in step 2, and the performance of the composite obtained is: the bending strength is 930 MPa, the Young's modulus is 310 GPa, the ball drop performance is 32 cm, and the point pressure performance is 105 N.

[0148] Example 30

[0149] Different from Example 1, only hot-pressing curing was used in Step 2, and the performance of the obtained composite part was: flexural strength of 970 MPa, Young's modulus of 385 GPa, ball drop performance of 38 cm, and point pressure performance of 116 N.

[0150] From the above examples and comparative examples, it can be found that the ceramic glass composite part of the present application has significantly improved mechanical properties compared with single ceramic or single glass material parts. The ball drop performance of the optimal Example 1 reached 45 cm, which was increased by 55.2% compared with the single zirconia ceramic substrate (29 cm) and by 73% compared with the single microcrystalline glass substrate (26 cm); the point pressure performance reached 130 N, which was increased by 20.4% compared with the single zirconia ceramic substrate (108 N) and by 44.4% compared with the single microcrystalline glass substrate (90 N); the flexural strength and Young's modulus were also significantly better than those of the single substrate; and it was also better than the composite part without thinning, i.e., Example 1-7 was better than Comparative Example 1; and it was also applicable to ordinary glass. This fully proves that the present application realizes the synergistic effect of "1+1>2" through the ceramic glass composite structure design and the thinning process optimization, the mechanical properties are not reduced but increased while being thinned, and the light weight and impact resistance high performance requirements of the mobile phone backboard are met.

Claims

1. A ceramic glass composite having strong impact resistance, consisting of a ceramic layer, a glass layer, and a bonding layer, characterized in that, The ceramic glass composite has a bending strength of 1000 MPa or more, a drop ball performance of not less than 37 cm, and a point pressure value of not less than 110 N, and has a thickness of 0.3-0.6 mm, wherein the ceramic layer has a thickness of 0.09-0.30 mm and is made of zirconium oxide ceramic or silicon nitride ceramic; the glass layer has a thickness of 0.15-0.30 mm and is made of microcrystalline glass or chemically strengthened ordinary glass; and the adhesive layer has a thickness of 0.005-0.05 mm and is made of an epoxy resin-based layer or an acrylic resin-based layer.

2. A method of producing a ceramic glass composite having high impact resistance as claimed in claim 1, characterized in that, The method comprises the following steps: Step 1: bonding a ceramic layer with a thickness of 0.25-0.45 mm and a glass layer with a thickness of 0.15-0.30 mm through an adhesive layer with a thickness of 0.005-0.05 mm to obtain an initial composite; Step 2: performing a curing treatment on the initial composite obtained in step 1; Step 3: performing a thinning treatment on the initial composite obtained in step 2 to thin the ceramic layer to a thickness of 0.09-0.30 mm to obtain a final product.

3. The method for preparing a ceramic-glass composite with strong impact resistance according to claim 2, characterized in that, The adhesive layer in step 1 is prepared by a slot coating process, a doctor blade coating process or a dispensing coating process.

4. The method for preparing a ceramic-glass composite with strong impact resistance according to claim 2, characterized in that, The curing process in step 2 is UV curing, thermal curing or hot-pressing curing, wherein the UV curing process specifically comprises irradiation of ultraviolet light with a wavelength of 320-390 nm at an irradiation intensity of 1000-4000 mJ / cm2 for 20-60 s; the thermal curing process is performed at a curing temperature of 60-100 ℃ for 1-24 h; and the hot-pressing curing process is performed at a curing temperature of 60-100 ℃, a curing pressure of 0.5-1.5 MPa and a curing time of 1-24 h.

5. The method for preparing a ceramic-glass composite with strong impact resistance according to claim 2, characterized in that, The thinning treatment in step 3 specifically comprises coarse grinding followed by fine grinding; the coarse grinding is performed using a 320-600 mesh diamond grinding wheel at a spindle speed of 3000-5000 rpm, a feeding speed of 5-10 μm / s and a pressing force of 20-50 N; and the fine grinding is performed using a 2000-3000 mesh resin-bonded diamond grinding wheel at a spindle speed of 8000-12000 rpm, a feeding speed of 0.5-1 μm / s and a pressing force of 5-15 N, so that the final roughness Ra of the outer surface of the ceramic layer is not more than 0.01 μm.

6. An electronic device, comprising: The ceramic glass composite has a bending strength of 1000 MPa or more, a drop ball performance of not less than 37 cm, and a point pressure value of not less than 110 N, and has a thickness of 0.3-0.6 mm, wherein the ceramic layer has a thickness of 0.09-0.30 mm and is made of zirconium oxide ceramic or silicon nitride ceramic; the glass layer has a thickness of 0.15-0.30 mm and is made of microcrystalline glass or chemically strengthened ordinary glass; and the adhesive layer has a thickness of 0.005-0.05 mm and is made of an epoxy resin-based layer or an acrylic resin-based layer.

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