High toughness impact resistant zirconia ceramic composite and method of making same

Abstract

The present application relates to the technical field of composite materials, and particularly relates to a high-toughness impact-resistant zirconia ceramic composite material and a preparation method thereof. The present application provides a preparation method of a high-toughness impact-resistant zirconia ceramic composite material, and the method is characterized in that the method comprises the following steps: soaking continuous alumina fiber fabric in resin to prepare prepreg; laying the prepreg on one side of a zirconia ceramic sheet, and then laying a zirconia ceramic sheet or multiple layers of prepreg on one side of the prepreg to obtain a lay-up material; vacuum-pressing forming the lay-up material; and heating and curing the vacuum-pressing formed lay-up material to obtain a composite material. The present application provides a high-toughness impact-resistant zirconia ceramic composite material and a preparation method thereof, and can provide a material with good texture, excellent mechanical properties and high electromagnetic signal transmittance.

Description

Technical Field

[0001] This invention relates to the field of composite materials technology, and in particular to a high-toughness, impact-resistant zirconia ceramic composite material and its preparation method. Background Technology

[0002] As 3C electronic products develop towards high-end and personalized features, their backplate and shell materials not only need to have excellent mechanical properties, wear resistance and aesthetics (such as ceramic texture), but also need to meet the high wave transmission requirements of wireless communication signals.

[0003] Currently, the mainstream backplate materials and technical solutions include: 1. Pure ceramic backplates (mainly zirconia ceramics): These have advantages such as high hardness, wear resistance, good texture, and excellent biocompatibility. However, their inherent brittleness leads to poor impact resistance, making them prone to catastrophic fracture when subjected to drops or point impacts, resulting in low yield and high cost. 2. Glass backplates: These have mature technology, controllable cost, and good light transmittance, but their hardness and wear resistance are inferior to ceramics, making them prone to scratches and breakage. 3. Fiber-reinforced resin-based composite backplates: Glass fiber reinforced composite materials (fiberglass): These have low cost, but their specific strength and specific modulus are relatively low, and their appearance, texture, and wear resistance cannot compare with ceramics. 4. Carbon fiber reinforced composite materials: These have extremely high specific strength and specific modulus, but the conductivity of carbon fibers can severely shield electromagnetic signals, requiring the design of additional signal windows, increasing structural complexity and design difficulty.

[0004] Therefore, in order to address the above problems, there is an urgent need for a material with good texture, excellent mechanical properties, and high electromagnetic signal transmittance. Summary of the Invention

[0005] This invention provides a high-toughness, impact-resistant zirconia ceramic composite material and its preparation method, which can provide a material with good texture, excellent mechanical properties and high electromagnetic signal transmittance.

[0006] In a first aspect, embodiments of the present invention provide a method for preparing a high-toughness, impact-resistant zirconia ceramic composite material, comprising: A prepreg is made by impregnating continuous alumina fiber fabric with resin. The prepreg is laid on one side of a zirconia ceramic sheet, and then a zirconia ceramic sheet or a multilayer prepreg is laid on the other side of the prepreg to obtain a layup material. The layup material is vacuum-pressurized and molded. The vacuum-pressurized layup material is heated and cured to obtain a composite material.

[0007] Optionally, the thickness of the zirconia ceramic sheet is 0.1~0.5mm, and the surface of the zirconia ceramic sheet is subjected to roughening, cleaning and activation treatment.

[0008] Optionally, the fiber diameter of the continuous alumina fiber fabric is 10~12μm.

[0009] Optionally, the thickness of each prepreg layer is 0.08~0.15mm.

[0010] Optionally, the areal density of the continuous alumina fiber fabric is 100 g / m³. 2 .

[0011] Optionally, during the preparation of the layup material, before laying the next layer of material, a flexible energy-absorbing adhesive film is laid after each layer of zirconia ceramic sheet or the prepreg is laid. The flexible energy-absorbing adhesive film includes a polyurethane adhesive film.

[0012] Optionally, the volume fraction of continuous alumina fibers accounts for 50%-70% of the composite material layer, and the porosity of the composite material is less than 2%.

[0013] Optionally, The preparation method of the resin includes: Weigh out the fluorinated active ester and bisphenol A type epoxy resin according to the equivalent ratio of active ester group to epoxy group of 1:1 to 1:1.1, add nano-sized SiO2 filler of one-fifth of the mass of fluorinated active ester, and mix thoroughly in a mixer. Add 0.5~1.0 wt% of curing accelerator 4-dimethylpyridine and continue mixing until homogeneous to obtain the resin; wherein the epoxy equivalent of the bisphenol A type epoxy resin is 180~190 g / eq.

[0014] Optionally, The preparation method of the fluorinated active ester includes: Add 1 g / eq hexafluoroisopropyl diphenol and an appropriate amount of anhydrous tetrahydrofuran to the reaction flask, and stir until completely dissolved; Then, under ice-water bath conditions of 0~5℃, 2.2 mol of NaOH solid was added in batches and the reaction was stirred for 30~60 min to completely convert the phenolic hydroxyl groups into sodium phenolate. 2.1 g / eq of p-toluyl chloride was dissolved in anhydrous tetrahydrofuran to prepare a solution. The solution was then slowly added dropwise to the reaction flask through a constant pressure dropping funnel under ice-water bath conditions, and the dropping rate was controlled so that the system temperature did not exceed 10 °C. The temperature was raised to room temperature, and the reaction was stirred for another 4-6 hours. After the reaction was completed, the reaction solution was poured into deionized water, and a white or pale yellow solid precipitate was formed. After purification, the purified fluorinated active ester was obtained.

[0015] Secondly, embodiments of the present invention also provide a high-toughness, impact-resistant zirconia ceramic composite material, prepared according to any of the preparation methods described above.

[0016] Compared with the prior art, the present invention has at least the following beneficial effects: 1. Structural Innovation: It pioneered a laminated structure of "zirconia ceramic surface layer + continuous alumina fiber composite core layer", which solved the problem of ceramic brittleness from the structural design level and achieved the optimal solution of surface performance and overall toughness.

[0017] 2. Innovative Material Combination: For the first time, continuous alumina fiber-reinforced low-dielectric resin-based composite material is introduced as a structural toughening layer into the ceramic backplate of consumer electronics. This material combines superior mechanical properties compared to fiberglass, specific strength / modulus comparable to carbon fiber composites, and unique wave transmission characteristics.

[0018] 3. Synergistic Performance Innovation: The backplate prepared by this invention simultaneously achieves four characteristics that are difficult to achieve with traditional single materials: ① ceramic-like surface hardness and texture; ② fracture toughness and impact resistance close to engineering plastics or metals; ③ omnidirectional unshielded electromagnetic signal transmission capability; ④ lightweight.

[0019] 4. Process innovation: The medium-low temperature resin-based composite material molding process is used to replace or partially replace the high-temperature ceramic sintering process, avoiding the interfacial compatibility problem between the fiber and the ceramic matrix at high temperatures. The process is more stable and controllable, which is beneficial for the manufacturing and cost control of complex configuration products. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a flowchart of a method for preparing a high-toughness, impact-resistant zirconia ceramic composite material provided by the present invention; Figure 2 This is a photograph of a high-toughness, impact-resistant zirconia ceramic composite material provided by the present invention. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0023] Please refer to Figure 1and Figure 2 This invention provides a method for preparing a high-toughness, impact-resistant zirconia ceramic composite material, comprising: A prepreg is made by impregnating continuous alumina fiber fabric with resin. The prepreg is laid on one side of a zirconia ceramic sheet, and then a zirconia ceramic sheet or a multilayer prepreg is laid on the other side of the prepreg to obtain a layup material. The layup material is vacuum-pressurized and molded. The vacuum-pressurized layup material is heated and cured to obtain a composite material.

[0024] In this embodiment, dense zirconia ceramic is used as the surface layer. Its high hardness gives the surface layer good wear resistance, good texture, and biocompatibility. The internal fiber prepreg provides good toughness, improves strength and modulus, and has excellent wave transmission properties, making it suitable for use in electronic products.

[0025] In some embodiments of the present invention, the thickness of the zirconia ceramic sheet is 0.1~0.5mm, and the surface of the zirconia ceramic sheet is subjected to roughening, cleaning and activation treatment.

[0026] In this embodiment, by roughening, cleaning and activating the surface of the zirconia ceramic sheet to be bonded, a micro-rough structure can be formed on the surface to be bonded, increasing the bonding area and mechanical interlocking force.

[0027] In some embodiments of the present invention, the fiber diameter of the continuous alumina fiber fabric is 10~12μm.

[0028] In this embodiment, the fiber diameter is preferably 11 μm, at which point the fiber has high strength and flexibility. When the fiber diameter is <10 μm: the fiber is soft, the tensile strength is insufficient, and the molding qualification rate decreases by about 30%. When the fiber diameter is >12 μm: the fiber becomes more brittle, has more fuzz, which is not conducive to weaving and traction, and the bending strength decreases by about 18%.

[0029] In some embodiments of the present invention, the thickness of each prepreg layer is 0.08~0.15 mm.

[0030] In this embodiment, the thickness of each prepreg layer is 0.08~0.15 mm, preferably 0.1 mm. When the thickness of a single layer is <0.08 mm, the fiber load-bearing capacity is insufficient and the bending strength decreases by about 25%. When the thickness of a single layer is >0.15 mm, the composite ceramic back plate is too thick, which is not conducive to the thin and light design of mobile phones.

[0031] In some embodiments of the present invention, the areal density of the continuous alumina fiber fabric is 100 g / m³. 2 .

[0032] In this embodiment, the areal density is preferably 100 g / m³. 2 When the fiber cloth has an areal density of 80 g / m 2 At this time: insufficient fiber content and high resin content result in a decrease of approximately 30% in strength and tensile toughness; when the fiber fabric surface density is 120 g / m². 2 When: The interlayer thickness exceeds the standard, the resulting ceramic back panel is too thick, which is not conducive to the thin and light design of mobile phones.

[0033] In some embodiments of the present invention, during the preparation of the layup material, a flexible energy-absorbing adhesive film, including a polyurethane adhesive film, is laid before laying the next layer of material after each layer of zirconia ceramic sheet or the prepreg is laid. This flexible absorbable layer further enhances the material's impact resistance and energy absorption performance.

[0034] In some embodiments of the present invention, the volume fraction of continuous alumina fibers accounts for 50%-65% of the composite material layer, and the porosity of the composite material is less than 2%.

[0035] In some embodiments of the present invention The method for preparing the resin includes: Weigh out the fluorinated active ester and bisphenol A type epoxy resin according to the equivalent ratio of active ester group to epoxy group of 1:1 to 1:1.1, add nano-sized SiO2 filler of one-fifth of the mass of fluorinated active ester, and mix thoroughly in a mixer. Add 0.5~1.0 wt% of curing accelerator 4-dimethylpyridine and continue mixing until homogeneous to obtain the resin; wherein the epoxy equivalent of the bisphenol A type epoxy resin is 180~190 g / eq.

[0036] In some embodiments of the present invention The preparation method of the fluorinated active ester includes: Add 1 g / eq hexafluoroisopropyl diphenol and an appropriate amount of anhydrous tetrahydrofuran to the reaction flask, and stir until completely dissolved; Then, under ice-water bath conditions of 0~5℃, 2.2 mol of NaOH solid was added in batches and the reaction was stirred for 30~60 min to completely convert the phenolic hydroxyl groups into sodium phenolate. 2.1 g / eq of p-toluyl chloride was dissolved in anhydrous tetrahydrofuran to prepare a solution. The solution was then slowly added dropwise to the reaction flask through a constant pressure dropping funnel under ice-water bath conditions, and the dropping rate was controlled so that the system temperature did not exceed 10 °C. The temperature was raised to room temperature, and the reaction was stirred for another 4-6 hours. After the reaction was completed, the reaction solution was poured into deionized water, and a white or pale yellow solid precipitate was formed. After purification, the purified fluorinated active ester was obtained.

[0037] Specifically, the detailed preparation process of the resin provided in this application can be as follows: Preparation of the activated ester: In a four-necked flask equipped with a mechanical stirrer, thermometer, reflux condenser, and constant-pressure dropping funnel, 1 g / eq hexafluoroisopropylbenzene and an appropriate amount of anhydrous tetrahydrofuran were added sequentially and stirred until completely dissolved. Then, under ice-water bath conditions (0-5℃), 2.2 mol of solid NaOH was added in portions, and the reaction was stirred for 30-60 min to completely convert the phenolic hydroxyl groups to sodium phenolate. 2.1 g / eq of p-toluyl chloride was dissolved in anhydrous tetrahydrofuran to prepare a solution, which was then slowly added dropwise to the reaction flask under ice-water bath conditions using a constant-pressure dropping funnel, controlling the dropping rate to keep the system temperature below 10℃. After the addition was complete, the ice bath was removed, and the temperature was slowly raised to room temperature (25℃), and the reaction was continued with stirring for 4-6 h. After the reaction was complete, the reaction solution was poured into a large amount of deionized water, and a white or pale yellow solid precipitate formed. The precipitate was collected by vacuum filtration, washed 2-3 times with deionized water, and then washed with a small amount of cold methanol. The crude product was dissolved in dichloromethane and dried overnight with anhydrous magnesium sulfate. After filtration to remove the drying agent, the solvent was removed by vacuum distillation to obtain the purified fluorinated active ester, with a yield of approximately 70-80%. The selected ingredients included hexafluoroisopropylbenzene with a purity >98%, p-toluyl chloride with a purity ≥98%, sodium hydroxide solid of analytical grade, and anhydrous magnesium sulfate of analytical grade.

[0038] Preparation of activated ester low-dielectric resin: Weigh fluorinated activated ester and bisphenol A type epoxy resin according to the equivalent ratio of active ester groups to epoxy groups (1:1~1:1.1), add an appropriate amount of nano-sized SiO2 filler (surface modified with silane coupling agent), and mix thoroughly in a mixer. Add curing accelerator 4-dimethylpyridine (0.5~1.0 wt%), and continue mixing until a uniform paste is formed. Pour the mixed resin system into a beaker, and after degassing in a vacuum oven for 15~30 min, the activated ester low-dielectric epoxy resin is obtained. The resin viscosity is 300~500 mPa·s, and its cured dielectric constant (Dk) is less than 3.5, and its loss factor (Df) is less than 0.01. The epoxy equivalent of the bisphenol A type epoxy resin is 180~190 g / eq.

[0039] Preparation of continuous alumina fiber low dielectric prepreg: Take a plain weave continuous alumina fiber cloth with a width of 1m and a surface density of 100g / m2, arrange the fibers in a muffle furnace and heat to 600~900℃, keep it at that temperature for 1~2h, and remove the sizing agent from its surface; then brush the above-prepared activated ester low dielectric epoxy resin onto the high-temperature treated fiber cloth, and then use a metal cylindrical rod to roll and extrude the excess resin to ensure that the fiber volume fraction is between 50% and 70%.

[0040] In some embodiments of the present invention, vacuum pressure forming includes: vacuum bag forming, placing the laminate in a No. 45 steel mold, using vacuum bag pressing to remove air bubbles between layers, ensuring that the vacuum degree is not less than 0.88 during laying, and applying uniform pressure to ensure that each layer is tightly bonded.

[0041] In some embodiments of the present invention, heat curing includes: placing the vacuum-packed laminate into a forced-air drying oven and heating it under a specific temperature profile and pressure to cure the resin matrix, thereby firmly bonding the zirconia ceramic sheet and the continuous alumina fiber reinforcement into a single unit. After curing, a zirconia ceramic composite material product is obtained. To ensure the strength and performance stability of the zirconia ceramic composite material, the curing temperature is between 180℃ and 200℃ with multiple temperature gradients, the curing time is 2-8 hours, the volume fraction of the continuous alumina fiber accounts for 50%-65% of the composite material layer, the porosity of the zirconia ceramic composite material product is less than 2%, the thickness is less than 1 GHz, and the dielectric constant of the composite material is less than 4.5 and the dielectric loss is less than 0.02 at room temperature.

[0042] After curing, post-processing can be performed: after demolding, trimming, grinding, polishing and possible surface coating treatment (such as AF coating) are carried out to obtain the final composite ceramic back plate product with a thickness between 1.0 and 1.6 mm.

[0043] This invention also provides a high-toughness, impact-resistant zirconia ceramic composite material, prepared according to any of the preparation methods described in the above embodiments.

[0044] To more clearly illustrate the technical solution and advantages of the present invention, the following describes the solution of this application in detail through several embodiments.

[0045] Example 1: (Sandwich Structure) 1. Take 500g of hexafluoroisopropylbenzene and 1000g of anhydrous tetrahydrofuran, and slowly pour them into a four-necked flask. Then connect a water bath, mechanical stirrer, thermometer, reflux condenser, and constant-pressure dropping funnel, and stir at room temperature until completely dissolved. Then, under ice-water bath conditions (0~5℃), add 40g of NaOH solid in batches, stirring for 30~60 min to completely convert the phenolic hydroxyl groups to sodium phenolate. Simultaneously, take 1100ml of p-toluyl chloride and place it in a 1000ml beaker, pour in an appropriate amount of anhydrous tetrahydrofuran and mix to prepare a solution. Slowly add this solution dropwise to the reaction flask under ice-water bath conditions using a constant-pressure dropping funnel, controlling the dropping rate to keep the system temperature below 10℃. After the addition is complete, remove the ice bath, slowly raise the temperature to room temperature (25℃), and continue stirring for 4~6 h. After the reaction is complete, pour the reaction solution into a beaker, then add a large amount of deionized water, and a white or pale yellow solid precipitate will form. The precipitate was then collected by vacuum filtration using a filter. After washing 2-3 times with deionized water, it was washed again with a small amount of cold methanol to obtain the crude fluorinated active ester. 300 ml of dichloromethane was then used to dissolve the crude product in a beaker, and 200 g of anhydrous magnesium sulfate was added for drying for at least 12 hours to remove residual distilled water. The desiccant was then removed by filtration with filter paper. The desiccant-free crude product was then poured into a distillation flask, and a Kri-type distillation head, mechanical stirrer, thermometer, reflux condenser, receiving flask, and vacuum pump were connected. The dichlorotoluene solvent was removed by vacuum distillation to obtain 452 g of purified fluorinated active ester.

[0046] 2. Weigh 200g of fluorinated active ester and 220g of bisphenol A epoxy resin according to the equivalent ratio of active ester groups to epoxy groups (1:1.1). Add 20g of SiO2 filler with an average particle size of 50nm (surface modified with silane coupling agent) and mix thoroughly in a mixer. Then add 55g of curing accelerator 4-dimethylpyridine (0.5~1.0 wt%) and continue mixing until homogeneous. Pour the mixed resin system into a beaker and degas in a vacuum oven at room temperature for 15~30 min to obtain activated ester low-medium epoxy resin with a viscosity of 360mPa.s.

[0047] 3. Take a plain-weave continuous alumina fiber cloth with dimensions of 1m×1m and a surface density of 100g / m^2. Arrange the fibers in a muffle furnace and heat to 600℃. Hold for 2 hours to remove the sizing agent from the surface. Then, apply the activated ester low-dielectric epoxy resin prepared above to the high-temperature treated alumina fiber cloth with a brush. Use a metal cylindrical rod to roll and extrude the excess resin to obtain a continuous alumina fiber low-dielectric prepreg with a fiber volume fraction of 62%.

[0048] Two yttrium-stabilized zirconia ceramic sheets, each measuring 100×100×0.2mm, were laser-microtextured on one side. Two 100×100×0.01mm polyurethane films and ten 100×100×0.1mm continuous alumina fiber low-dielectric prepregs were then stacked in a 100×100×2mm No. 45 steel mold in the order of "ceramic / TPU film / 10 layers of prepreg / TPU film / ceramic". The mold was then sealed using a vacuum bag. After connecting a vacuum gauge and a vacuum pump to evacuate the vacuum, the vacuum level of the vacuum bag was maintained at 0.95. The vacuum-sealed stack and... The mold was placed in a forced-air drying oven and cured under vacuum pressure. During curing, the vacuum bag vacuum level was maintained above 0.88. The curing temperature profile was as follows: heating at 2℃ / min to 65℃, holding for 2 hours; then heating at 1℃ / min to 130℃, holding for 1 hour; finally heating at 2℃ / min to 185℃, holding for 2 hours. After the holding period, the temperature was allowed to cool naturally to below 40℃. The mold was then removed from the forced-air drying oven and demolded. After trimming and surface polishing, a zirconia ceramic composite plate with a thickness of 1.42 mm was obtained. Performance tests were conducted on the zirconia ceramic composite plate, and the results are as follows: four-point bending strength 1310 MPa, fracture toughness (KIC) 20.4 MPa·m^1 / 2, no cracks on the back side in repeated drop ball impact tests (100g steel ball, 1m height impact) (more than three times). The dielectric constant (10GHz) is 4.5 (ceramic itself approximately ~26, composite layer ~3.8), and the signal transmission efficiency is >95%.

[0049] Comparison Case 1 (Sintered Zirconia Body Toughened with Short-Cut Alumina Fibers) Procedure: 20 vol% of chopped alumina fibers (length ~100 μm) are mixed with zirconia powder, and then dry-pressed using conventional processes, followed by high-temperature sintering at 1300℃ for 2 hours to produce zirconia ceramic matrix composite plates of equal thickness. Because the grain size of alumina fibers coarsens rapidly above 1300℃, causing a rapid decline in fiber properties, the sintering temperature cannot exceed 1300℃.

[0050] Performance testing: Four-point bending strength is approximately 350 MPa, and fracture toughness is approximately 9.1 MPa·m^1 / 2. Under the same conditions as in Implementation Case 1, visible microcracks appeared on the back side during the first drop ball impact test. This process requires controlling the aspect ratio of the fibers and matching the sintering temperature of the chopped alumina fibers and ceramic powder. However, the sintering temperature for zirconia ceramics to reach densification is generally above 1530℃. Therefore, the sintered density of chopped alumina fiber-toughened zirconia is relatively low, with more internal porosity. Furthermore, the strength of the prepared chopped alumina fiber-toughened zirconia sintered body is low, and the yield of thin sheet sizes is also low.

[0051] Example 2 (single-sided ceramic structure, for use in shells with internal support structures): Steps: Following the same steps as in Case Study 1, prepare fluorinated active ester, activated ester low-dielectric epoxy resin, and continuous alumina fiber low-dielectric prepreg. Take a 100×100×0.2mm yttrium-stabilized zirconia ceramic sheet (contact surface sandblasted). Cut 10 pieces of 100×100×0.1mm continuous alumina fiber low-dielectric prepreg impregnated with activated ester low-dielectric epoxy resin. Also take a 100×100×0.01mm polyurethane film and lay them on a No. 45 steel mold to form a “ceramic-TPU film-prepreg”. The structural laminate was then placed in a vacuum bag and sealed. A vacuum pump and pressure gauge were connected to evacuate the vacuum bag to a vacuum level of 0.98. The material was cured under vacuum pressure at 130°C. The curing temperature curve was as follows: increase the temperature by 2°C / min to 60°C, hold for 2 hours, then increase the temperature by 1°C / min to 140°C, hold for 1 hour, and finally increase the temperature by 2°C / min to 180°C, hold for 2 hours. After the holding period, the material was allowed to cool naturally to below 40°C. It was then removed from the drying oven and demolded. After CNC machining, trimming, and polishing, a zirconia ceramic composite plate with a thickness of 1.21 mm was obtained. Performance: Four-point bending strength is approximately 1456 MPa, and fracture toughness is approximately 24.8 MPa·m^1 / 2. Due to the higher volume fraction of the continuous alumina fiber reinforced resin layer in the zirconia ceramic composite material compared to the sandwich structure, the single-sided ceramic structure exhibits higher strength and toughness. Repeated drop ball impact tests (100g steel ball, 1m height impact) show no cracks on the back side (more than three times). The impact surface is the ceramic surface, and the dielectric constant (10GHz) is 4.1 (approximately ~26 for the ceramic itself and ~3.8 for the composite material layer). The signal transmission efficiency is >95%. It combines the wear-resistant texture of the ceramic outer surface with the extremely high overall toughness and designability of the composite material layer, making it particularly suitable for complex structural components.

[0052] Comparative Case 2 (Glass fiber reinforced epoxy resin toughened zirconia ceramic sheet): Procedure: Following the same steps as in Example 2, fluorinated active ester, activated ester low-dielectric epoxy resin, continuous glass fiber low-dielectric prepreg, and zirconia ceramic composite material were prepared. The only difference was that the continuous alumina fiber cloth was replaced with continuous glass fiber cloth of the same size and areal density. All other steps and processes were identical to Example 2. After trimming and surface polishing, a zirconia ceramic glass fiber composite board with a thickness of 1.21 mm was obtained. Performance Testing: The four-point bending strength was approximately 553 MPa, and the fracture toughness was approximately 10.3 MPa·m^1 / 2. In the first drop ball impact test under the same conditions, with the ceramic surface as the impact surface, microcracks appeared in the zirconia ceramic glass fiber composite board. After the second drop ball impact test under the same conditions, the zirconia ceramic glass fiber composite board shattered, demonstrating that the zirconia ceramic sheet toughened with continuous alumina fiber has higher toughness and impact resistance than that toughened with glass fiber.

[0053] Comparison Case 3 (Comparison with pure zirconia ceramic sheets) Two yttrium-stabilized zirconia ceramic sheets of the same size and thickness as the zirconia ceramic composite plate in Implementation Case 2 were obtained from the market. They were subjected to the same performance tests, and the results are as follows: four-point bending strength approximately 832 MPa, fracture toughness approximately 6.3 MPa·m^1 / 2. Visible microcracks appeared on the back side during the first drop ball impact test under the same conditions. The impacted surface was the ceramic surface. The zirconia ceramic sheet shattered during the first drop ball impact test under the same conditions, proving that zirconia ceramics are brittle and have insufficient impact resistance. After adding continuous alumina fiber toughening, the toughness increased, and the impact resistance was also improved.

[0054] Comparison Case 4 (Comparison of TPU film thickness) Using the same test procedures as Case 1, but with TPU film products of different thicknesses, the effects on product performance are as follows. The table above shows that the 0.01 mm TPU film achieves the optimal balance between energy absorption, structural rigidity, and dielectric properties. If it is too thin, the energy absorption will be insufficient, while if it is too thick, the structural strength will be reduced and the wave transmission will be worsened.

[0055] Comparison Case 5 (Comparison of Zirconia Ceramic Thickness) Using the same experimental procedures as in Case 1, but with zirconia ceramic sheets of varying thicknesses, the product was tested, and the impact on product performance was as follows:

[0056] The table above leads to the conclusion that the 0.3 mm ceramic layer balances surface texture, structural strength, impact resistance, thinness, and mass production, overcoming the inherent defects of pure ceramic sheets being easily broken and brittle, and thick plates being heavy and brittle.

[0057] Finally, it should be noted that the above embodiments and comparative examples are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments and comparative examples, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments and comparative examples, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments and comparative examples of the present invention.

Claims

1. A method for preparing a high-toughness, impact-resistant zirconia ceramic composite material, characterized in that, include: A continuous alumina fiber fabric is impregnated in resin to make a prepreg. The prepreg is laid on one side of a zirconia ceramic sheet, and then a zirconia ceramic sheet or a multilayer prepreg is laid on the other side of the prepreg to obtain a layup material. The layup material is vacuum-pressurized and molded. The layup material formed under vacuum pressure is heated and cured to obtain a composite material.

2. The method for preparing a high-toughness, impact-resistant zirconia ceramic composite material according to claim 1, characterized in that, The thickness of the zirconia ceramic sheet is 0.1~0.5mm, and the surface of the zirconia ceramic sheet is roughened, cleaned and activated.

3. The method for preparing a high-toughness, impact-resistant zirconia ceramic composite material according to claim 1, characterized in that, The continuous alumina fiber fabric has a fiber diameter of 10~12μm.

4. The method for preparing a high-toughness, impact-resistant zirconia ceramic composite material according to claim 1, characterized in that, The thickness of each prepreg layer is 0.08~0.15mm.

5. The method for preparing a high-toughness, impact-resistant zirconia ceramic composite material according to claim 1, characterized in that, The areal density of the continuous alumina fiber fabric is 100 g / m³. 2 .

6. The method for preparing a high-toughness, impact-resistant zirconia ceramic composite material according to claim 1, characterized in that, During the preparation of the layup material, before laying the next layer of material, a flexible energy-absorbing adhesive film is laid after each layer of zirconia ceramic sheet or the prepreg is laid. The flexible energy-absorbing adhesive film includes a polyurethane adhesive film.

7. The method for preparing a high-toughness, impact-resistant zirconia ceramic composite material according to claim 1, characterized in that, The volume fraction of continuous alumina fibers accounts for 50%-70% of the composite material layer, and the porosity of the composite material is less than 2%.

8. The method for preparing a high-toughness, impact-resistant zirconia ceramic composite material according to claim 1, characterized in that, The method for preparing the resin includes: Weigh out the fluorinated active ester and bisphenol A type epoxy resin according to the equivalent ratio of active ester group to epoxy group of 1:1 to 1:1.1, add nano-sized SiO2 filler of one-fifth of the mass of fluorinated active ester, and mix thoroughly in a mixer. Add 0.5~1.0 wt% of curing accelerator 4-dimethylpyridine and continue mixing until homogeneous to obtain the resin; wherein the epoxy equivalent of the bisphenol A type epoxy resin is 180~190 g / eq.

9. The method for preparing a high-toughness, impact-resistant zirconia ceramic composite material according to claim 8, characterized in that, The preparation method of the fluorinated active ester includes: Add 1 g / eq hexafluoroisopropyl diphenol and an appropriate amount of anhydrous tetrahydrofuran to the reaction flask, and stir until completely dissolved; Then, under ice-water bath conditions of 0~5℃, 2.2 mol of NaOH solid was added in batches and the reaction was stirred for 30~60 min to completely convert the phenolic hydroxyl groups into sodium phenolate. 2.1 g / eq of p-toluyl chloride was dissolved in anhydrous tetrahydrofuran to prepare a solution. The solution was then slowly added dropwise to the reaction flask through a constant pressure dropping funnel under ice-water bath conditions, and the dropping rate was controlled so that the system temperature did not exceed 10 °C. The temperature was raised to room temperature, and the reaction was stirred for another 4-6 hours. After the reaction was completed, the reaction solution was poured into deionized water, and a white or pale yellow solid precipitate was formed. After purification, the purified fluorinated active ester was obtained.

10. A high-toughness, impact-resistant zirconia ceramic composite material, characterized in that, It is prepared by the preparation method according to any one of claims 1-9.

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