Ceramic composite material with shell-like structure as well as preparation method and application of ceramic composite material

Abstract

The invention relates to the field of ceramic composite materials, in particular to a ceramic composite material with an imitated shell structure as well as a preparation method and application thereof, and the method comprises the following steps: (S.1) providing slurry containing ceramic particles and metal alloy particles which are subjected to surface functionalization so as to have magnetic responsiveness; (S.2) performing magnetic field-assisted slip casting to enable particles in the slurry to be in oriented arrangement under a rotating magnetic field to form a green body with a layered structure; and (S.3) carrying out spark plasma sintering on the green body to obtain the compact ceramic composite material with the shell-imitating structure. The composite material with the shell-like layered structure is successfully prepared by combining magnetic field assisted slip casting and spark plasma sintering processes, the fracture toughness and bending strength of the material are remarkably improved, and the defects that a traditional ceramic material is high in brittleness and low in reliability are effectively overcome.

Description

Technical Field

[0001] This invention relates to the field of ceramic composite materials, and in particular to a shell-like ceramic composite material, its preparation method, and its application. Background Technology

[0002] Alumina ceramic materials have long held an important position in the fields of biomedicine and engineering structures, thanks to their excellent biocompatibility, high hardness, and good chemical stability, making them an ideal choice for implants such as artificial joints and dental implants. However, these materials have always faced a fundamental contradiction in practical applications: their inherent brittleness leads to insufficient fracture toughness, making them prone to sudden fracture under impact or cyclic loading, which severely limits their reliability and service life in load-bearing critical components. In nature, the unique structure of seashells has provided inspiration for solving this problem—their typical "brick-and-mortar" layered design, in which up to 95% rigid aragonite lamellars alternate with 5% flexible biopolymer interfaces, achieves efficient energy dissipation through various mechanisms such as crack deflection and lamellar pull-out, thus possessing both high strength and high toughness. This bio-inspired approach has spurred the development of various biomimetic fabrication technologies, but existing methods still have significant limitations in terms of precise control of microstructure, balance of interfacial properties, and comprehensive mechanical properties.

[0003] Cryo-casting, a representative early biomimetic fabrication method, induces ice crystal growth by directionally freezing a ceramic suspension to form a directional porous structure, which is then impregnated to obtain a layered composite material. While this method can achieve a certain degree of structural anisotropy, its long preparation cycle and difficulty in precisely controlling the freezing rate result in materials with typically high porosity and insufficient densification. More importantly, the lamellar orientation formed during the freezing process is highly random, resulting in poor layer thickness uniformity. Furthermore, the interfacial bonding strength after polymer impregnation is weak, making it prone to delamination at the interface, thus the actual toughening effect is far lower than theoretically expected. Although some studies have attempted to combine hot pressing to improve density, the increased process complexity has brought new problems such as rising costs and difficulties in large-scale production.

[0004] On the other hand, the cumulative rolling and impregnation method orients sheet-like particles through mechanical rolling and folding operations, and then constructs layered composite materials through resin impregnation. This method is relatively simple and suitable for the preparation of planar structures, for example, it has shown some improvement in toughness in dental restorative materials. However, its limitations lie in its difficulty in handling complex three-dimensional shapes, the tendency of repeated rolling to introduce internal defects or delamination, and the low precision in controlling the interlayer spacing, resulting in poor structural consistency. More importantly, this method relies on polymers as the interface phase, and their thermal stability and durability are poor in high-temperature or harsh chemical environments, limiting the potential application of the material in high-temperature engineering fields.

[0005] The emergence of additive manufacturing technology has brought greater freedom to biomimetic structural design, especially 3D printing, which enables the customization of complex macroscopic geometries. Through techniques such as digital light processing or direct-write molding, scaffold structures can be pre-designed and combined with post-processing impregnation techniques. Some studies have also attempted to introduce magnetic or electric fields during the printing process to control particle orientation. However, with current technology, there is an inherent contradiction between printing accuracy and microstructure control: increasing printing resolution often means reducing the content of reinforcing phases, while increasing solid content affects ink flow and molding quality. Furthermore, interlayer bonding weaknesses and inherent porosity problems generated during printing are difficult to completely avoid, resulting in the final material's density and interfacial strength often failing to meet structural requirements. Although some studies have improved performance through metal impregnation or fiber embedding, high costs and process complexity remain obstacles to large-scale application.

[0006] While various methods exist for preparing shell-like ceramic composites, each has its limitations in terms of structural control precision, interface optimization, or performance balance. In particular, achieving the feasibility of large-scale fabrication remains a critical challenge for the industry, especially given the pursuit of high density, strong interfacial bonding, and controllable three-dimensional structures. These intertwined technical limitations create multiple obstacles to the application and promotion of high-performance structural ceramics, necessitating an innovative solution that comprehensively addresses these issues. Summary of the Invention

[0007] This application aims to overcome the shortcomings of existing ceramic composite materials, such as high brittleness, insufficient fracture toughness, imprecise control of biomimetic structures, low density, and weak interfacial bonding strength. Therefore, it provides a shell-like structure ceramic composite material, its preparation method, and its application to overcome the above-mentioned deficiencies.

[0008] To achieve the above-mentioned objectives, the present invention is implemented through the following technical solution: In a first aspect, the present invention provides a method for preparing a shell-like ceramic composite material, which includes the following steps: (S.1) Provide a slurry comprising ceramic particles and metal alloy particles that have been surface-functionalized to have magnetic responsiveness; (S.2) The particles in the slurry are oriented and aligned under a rotating magnetic field by magnetic field-assisted slurry injection molding to form a green embryo with a layered structure; (S.3) The green embryo is subjected to spark plasma sintering to obtain a dense shell-like ceramic composite material.

[0009] As described in the background section, the field of biomimetic ceramic materials has long faced a challenge: while the layered structure of natural seashells can effectively improve toughness, achieving such a fine structure is often accompanied by difficulties in densification, weak interfacial bonding, or high process complexity. Existing methods such as cryogenic casting, cumulative rolling, and even 3D printing have failed to properly balance the three objectives of "structural controllability," "material density," and "interfacial toughness."

[0010] Therefore, the core concept of this application is: whether a biomimetic layered framework can be accurately constructed under mild conditions, and then an interface phase with both strong bonding and high toughness can be introduced through an efficient densification process to synergistically improve the overall performance of the material while maintaining the integrity of the framework.

[0011] Based on the above concept, this application overcomes the above problems in three steps. First, the preparation of the slurry in step (S.1) is fundamental. The key is that it contains both ceramic particles and metal alloy particles. Compared with the defects of weak bonding and insufficient high-temperature resistance caused by using polymers as the interface phase in the prior art, this application achieves stronger interface bonding and the possibility of toughening through plastic deformation due to the pre-placement of the metal phase.

[0012] The magnetic field-assisted slurry casting (MASC) method used in step (S.2) is the core of achieving precise structural control. This step cleverly draws on the advantages of magnetic orientation technology in the preparation of anisotropic materials, but its application to ceramic-metal composite systems is a novel approach. By applying a rotating magnetic field to the slurry, the sheet-like particles (whether ceramic or pre-treated metal particles) are oriented, thus pre-forming a highly ordered, shell-like "brick-and-mortar" layered prototype in the preform stage. This step is carried out under mild wet conditions, avoiding early structural damage caused by high temperature and pressure, effectively solving the problems of high randomness in cryogenic casting structures and insufficient micro-orientation in 3D printing, laying the structural foundation for obtaining composite materials with consistent performance.

[0013] However, a precise skeleton alone is insufficient. If the subsequent densification process is inappropriate, such as using traditional atmospheric pressure sintering, the already formed fine structure may collapse or coarsen at high temperatures, making it difficult to achieve high density. Therefore, in step (S.3) of this application, spark plasma sintering (SPS) technology is used to directly heat the mold and powder with pulsed current, resulting in an extremely rapid heating rate, and axial pressure is applied throughout the sintering process. This combination of "rapid heating" and "pressure assistance" allows the green body to achieve densification at temperatures far below conventional sintering temperatures and in a very short time, maximally suppressing excessive grain growth and perfectly "freezing" and preserving the biomimetic layered structure constructed in step (S.2).

[0014] Therefore, this application combines MASC and SPS, two processes respectively adept at "structure shaping" and "rapid densification," to form a synergistic technological combination, achieving the following technical effects: First, in terms of structural control, this method achieves high-precision customization of shell-like layered structures. By adjusting the magnetic field conditions, the orientation angle and arrangement period of the layers can be flexibly adjusted, thereby achieving active design of the anisotropic properties of the material, which is unmatched by traditional powder metallurgy or reactive infiltration methods for preparing uniform structures. Second, in terms of interface properties, because the metal alloy forms a tightly bonded interface with the ceramic phase under high temperature and pressure during the SPS process, its bonding strength is much higher than that of the polymer interface. This strong interface ensures that the load can be effectively transferred from the brittle ceramic "brick" to the tough metal "clay," avoiding failure caused by early interface debonding. Most importantly, this unique coupling of "precise layered structure" and "strong and tough metal interface" activates the comprehensive effect of multiple toughening mechanisms. When subjected to external forces, the crack encounters alternating, extremely strong ceramic layers and excellent toughness metal layers during its propagation. Cracks cannot penetrate in a straight line; instead, they are forced to frequently deflect, branch, and even be "pinned" by the bridging metallic phase, significantly extending their propagation path. Simultaneously, the metallic phase undergoes plastic deformation under the stress at the crack tip, absorbing and dissipating a large amount of energy. The synergistic effect of these mechanisms allows the material to maintain the inherent high strength of ceramics while significantly improving its fracture toughness. This successfully overcomes the inherent shortcomings of traditional ceramic materials, such as high brittleness and low reliability, and resolves the contradiction between strength and toughness in homogeneous ceramic-metal composites.

[0015] Preferably, the ceramic particles are alumina micron flakes, and the metal alloy particles are aluminum-silicon alloy particles.

[0016] This application discovers that the sheet-like geometry of alumina microsheets is a fundamental prerequisite for achieving efficient magnetic field orientation. Compared to equiaxed particles, sheet-like microsheets experience greater torque in a magnetic field, enabling them to respond more sensitively and precisely to changes in magnetic field direction, thereby constructing a highly ordered, clearly defined biomimetic "brick-and-mortar" skeletal structure within the green body. This superior orientation characteristic resulting from the sheet-like morphology is a primary condition for achieving high-performance biomimetic structures. Such a regular layered arrangement is difficult to achieve when using spherical or amorphous ceramic powders.

[0017] In the subsequent SPS densification process, the metallic phase needs to form a strong and tough interfacial bond with the ceramic phase under high temperature and pressure. The aluminum-silicon alloy has a suitable melting point, allowing it to undergo sufficient plastic flow and even localized melting within the SPS process window temperature (e.g., 1200℃), effectively filling the tiny voids between ceramic layers and achieving a dense interfacial bond. Simultaneously, the silicon element in the alloy improves the wettability of the melt on the alumina ceramic, while the magnesium element may, to some extent, activate sintering and improve interfacial reactions. These factors combined contribute to a strong ceramic-metal interface bond.

[0018] Traditional ceramic-metal composite materials tend to use high-melting-point metals (such as titanium and nickel-based alloys) to pursue high-temperature performance, or adopt reactive synthesis systems to obtain stronger interfaces. However, this invention takes the opposite approach, selecting aluminum-silicon alloys that are more processable and lower in cost. Through the unique combination of processes mentioned above, it successfully solves the problems that this system may usually face, such as weak interfacial bonding and uneven alloy distribution, achieving an unexpectedly strong and toughened effect.

[0019] Preferably, the aluminum-silicon alloy is an AlSi10Mg alloy.

[0020] Preferably, the slurry also contains a dispersant, wherein the dispersant is anhydrous ethanol.

[0021] Preferably, in the magnetic field-assisted grouting molding, the strength of the rotating magnetic field is 5-20 mT.

[0022] Preferably, the discharge plasma sintering is carried out in a vacuum environment, with a sintering temperature of 1000-1400℃, a pressure of 30-50MPa, and a holding time of 20-40 minutes.

[0023] Preferably, the ceramic particles are magnetically responsive through surface functionalization, which includes the adsorption of superparamagnetic iron oxide nanoparticles.

[0024] The innovation lies in using a rotating magnetic field to drive the particles to align, thereby constructing a biomimetic layered structure. However, the alumina ceramic that forms the main framework of the composite material is inert and has almost no response to an applied magnetic field. By adsorbing superparamagnetic iron oxide nanoparticles, these ceramic microsheets are essentially endowed with "magnetism," enabling them to sensitively "sense" and respond to changes in the direction of the rotating magnetic field, thus undergoing directional rotation and alignment.

[0025] Choosing superparamagnetic iron oxide nanoparticles means that these nanoparticles can be strongly magnetized under an applied magnetic field, and their magnetism disappears rapidly once the magnetic field is removed, without generating residual magnetism. This characteristic effectively prevents the functionalized ceramic particles from attracting each other and agglomerating due to permanent magnetism, thus ensuring that the slurry has good fluidity and stability, which is indispensable for the smooth progress of the slurry casting process.

[0026] Preferably, the metal alloy particles are formed into a sheet-like structure by ball milling.

[0027] This application utilizes magnetic field-assisted slurry casting (MASC) to achieve the coordinated orientation and alignment of ceramic and metal particles, thereby constructing a regular shell-like "brick-and-mortar" structure. If the metal alloy particles in the slurry retain their original irregular or spherical morphology, they cannot achieve effective directional alignment under the influence of a rotating magnetic field, unlike the sheet-like ceramic particles. This morphological mismatch leads to a disordered distribution of the metal phase between the ceramic layers, becoming defect points in the structure, severely disrupting the continuity and consistency of the layered structure, and thus weakening the effectiveness of key toughening mechanisms such as crack deflection and interface bridging. Therefore, pre-treating the metal particles into sheet-like shapes is to give them geometric properties similar to ceramic "brick" sheets, enabling them to "integrate" and participate in the construction of an ordered layered framework.

[0028] Secondly, the present invention also provides a shell-like ceramic composite material, which is prepared by the method described above; The composite material has a layered structure with alternating ceramic and metal alloy phases, and its fracture toughness is not less than 10 MPa·√m.

[0029] Thirdly, the present invention also provides the application of the aforementioned shell-like ceramic composite material in artificial joints, bone repair materials, or aerospace structural components.

[0030] Therefore, the present invention has the following beneficial effects: First, this application successfully prepared a composite material with a shell-like layered structure by combining magnetic field-assisted slurry molding and spark plasma sintering processes, which significantly improved the fracture toughness and bending strength of the material and effectively overcame the defects of high brittleness and low reliability of traditional ceramic materials. Secondly, this process achieves high densification and strong interfacial bonding of composite materials. By replacing traditional polymers with metal alloy phases, it enhances load transfer efficiency and activates the synergistic effect of multiple toughening mechanisms such as crack deflection and bridging, thereby significantly improving toughness while maintaining high strength. Furthermore, this method offers high process controllability and flexibility, allowing for the customization of material properties by adjusting slurry composition and sintering parameters. It is suitable for large-scale production, providing a high-performance, low-cost new material solution for biomedical and engineering structural applications. Overall, these effects work synergistically, enabling a qualitative leap in the load-bearing capacity and damage resistance of composite materials. Attached Figure Description

[0031] Figure 1 This is a scanning electron microscope (SEM) image of an alumina microsheet.

[0032] Figure 2 This is a SEM image of an AlSi10Mg micron sheet.

[0033] Figure 3 A schematic diagram of the preparation of shell-like AlSi10Mg / alumina ceramic composite material by MASC and SPS is shown.

[0034] Figure 4 SEM images of the microstructure of the shell-like AlSi10Mg / alumina ceramic composite material prepared by MASC and SPS methods.

[0035] Figure 5 The density and porosity of the shell-like AlSi10Mg / alumina composite material are shown to vary with the AlSi10Mg content.

[0036] Figure 6 The study showed that the flexural strength and modulus of the shell-like AlSi10Mg / alumina composite material varied with the AlSi10Mg content.

[0037] Figure 7 The crack propagation of the shell-like pure alumina ceramic material is shown.

[0038] Figure 8 Crack propagation was shown in a shell-like AlSi10Mg / alumina ceramic composite containing 10 wt% AlSi10Mg.

[0039] Figure 9 Crack propagation was shown in a shell-like AlSi10Mg / alumina ceramic composite containing 20 wt% AlSi10Mg.

[0040] Figure 10 Crack propagation was shown in a shell-like AlSi10Mg / alumina ceramic composite containing 40 wt% AlSi10Mg.

[0041] Figure 11 The stress intensity factor and fracture toughness of the shell-like AlSi10Mg / alumina composite material are shown to vary with AlSi10Mg content.

[0042] Figure 12 SEM images of the fracture of the shell-like AlSi10Mg / alumina composite material are shown, revealing typical crack deflection and bifurcation.

[0043] Figure 13 SEM images of the fracture of the shell-like AlSi10Mg / alumina composite material are shown, revealing typical crack bridging.

[0044] Figure 14 SEM images of the fractured AlSi10Mg / alumina composite material mimicking a seashell are shown, revealing the pull-out of the sheet.

[0045] Figure 15 This is a scanning electron microscope (SEM) image of the fracture surface of the shell-like AlSi10Mg / alumina composite material. Detailed Implementation

[0046] The present invention will be further described below with reference to specific embodiments. Those skilled in the art will be able to implement the present invention based on these descriptions. Furthermore, the embodiments of the present invention described below are generally only some, not all, of the embodiments of the present invention. Therefore, all other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort should fall within the scope of protection of the present invention.

[0047] Example 1 A method for preparing a shell-like ceramic composite material includes the following steps: (S.1) Before constructing the shell-like structural material, a ceramic-alloy composite slurry with magnetic response must first be prepared: The raw materials used in this embodiment include alumina micron-sized sheets ( Figure 1 The particles were dispersed in anhydrous ethanol and contained in spherical AlSi10Mg particles (10-30 μm in diameter, 13-15 μm in diameter and 300 nm in thickness).

[0048] To achieve the magnetic response function of alumina microsheets, 10 g of alumina microsheets and 500 μL of superparamagnetic iron oxide nanoparticles were added to 700 mL of aqueous solution at pH = 7, and surface functionalization was achieved through electrostatic adsorption. The resulting magnetic alumina microsheets were then washed, collected, and dried overnight at room temperature.

[0049] To obtain an alloy sheet phase that can be co-oriented and assembled with alumina micron-sized sheets, 2g of spherical AlSi10Mg particles were ball-milled in 20mL of ethanol at 300 rpm for 12 hours to transform them from spherical to sheet-like shapes. Figure 2This morphological transformation is crucial for the subsequent construction of shell-like structures.

[0050] Finally, magnetic alumina microsheets and AlSi10Mg sheets were dispersed in anhydrous ethanol and homogenized by vortex mixing and mechanical stirring to prepare a stable magnetically responsive composite slurry.

[0051] (S.2) MASC used to prepare shell-like embryos: This embodiment utilizes MASC to prepare ceramic green bodies with specific orientation microstructures. The key point is that SPS graphite molds (50 mm in diameter) are directly used as forming molds, which effectively avoids the damage to the green body during the traditional transfer process.

[0052] The overall preparation process is shown in Figure 3, and the specific steps are as follows: The inner wall of the graphite mold is covered with graphite paper and placed on a porous gypsum substrate. Next, the assembled mold is placed in a horizontal magnetic field (10⁻¹⁵ mT). After the prepared slurry is cast into the mold, the alumina sheets align horizontally under the influence of the rotating magnetic field. As ethanol seeps through the porous gypsum substrate, the orientation structure is fixed, forming a dense green embryo composed of alternating alumina and AlSi₁₀Mg sheets. After drying overnight at room temperature, the green embryo can be sintered.

[0053] (S.3) SPS densification: In this embodiment, spark plasma sintering (SPS) technology is used to densify the shell-like embryo. This method has the advantages of rapid heating and efficient densification. It can heat up to 1200°C within 20 minutes and hold at 40 MPa pressure for 30 minutes to complete the sintering. At the same time, it effectively maintains the layered microstructure of the material and realizes the preparation of high-density composite materials.

[0054] The specific process is as follows: A graphite mold containing a ceramic green body is assembled with a graphite piston and placed in an SPS furnace. Pre-pressure is applied and a vacuum is drawn. Subsequently, the temperature is rapidly increased to 1200℃ under a pressure of 40 MPa and held for 30 minutes. The synergistic effect of high temperature and high pressure promotes a tight bond between the ceramic and alloy phase interfaces, achieving densification and structural stability of the composite material.

[0055] Example 2 A method for preparing a shell-like ceramic composite material includes the following steps: (S.1) Same as in Example 1.

[0056] (S.2) MASC used to prepare shell-like embryos: The specific steps are as follows: The inner wall of the graphite mold is covered with graphite paper and placed on a porous gypsum substrate. Next, the assembled mold is placed in a horizontal magnetic field (5-10 mT). After the prepared slurry is cast into the mold, the alumina sheets align horizontally under the influence of the rotating magnetic field. As ethanol seeps through the porous gypsum substrate, the orientation structure is fixed, forming a dense green embryo composed of alternating alumina and AlSi10Mg sheets. After drying overnight at room temperature, the green embryo can be sintered.

[0057] (S.3) SPS densification: The specific process is as follows: A graphite mold containing a ceramic green body is assembled with a graphite piston and placed in an SPS furnace. Pre-pressure is applied and a vacuum is drawn. Subsequently, the temperature is rapidly increased to 1000℃ under a pressure of 50 MPa and held for 40 minutes. The synergistic effect of high temperature and high pressure promotes the tight bonding of the ceramic and alloy phase interface, achieving densification and structural stability of the composite material.

[0058] Example 3 A method for preparing a shell-like ceramic composite material includes the following steps: (S.1) Same as in Example 1.

[0059] (S.2) MASC used to prepare shell-like embryos: The specific steps are as follows: The inner wall of the graphite mold is covered with graphite paper and placed on a porous gypsum substrate. Next, the assembled mold is placed in a horizontal magnetic field (15-20 mT). After the prepared slurry is cast into the mold, the alumina sheets align horizontally under the influence of the rotating magnetic field. As ethanol seeps through the porous gypsum substrate, the orientation structure is fixed, forming a dense green embryo composed of alternating alumina and AlSi10Mg sheets. After drying overnight at room temperature, the green embryo can be sintered.

[0060] (S.3) SPS densification: The specific process is as follows: A graphite mold containing a ceramic green body is assembled with a graphite piston and placed in an SPS furnace. Pre-pressure is applied and a vacuum is drawn. Subsequently, the temperature is rapidly increased to 1400℃ under a pressure of 30 MPa and held for 20 minutes. The synergistic effect of high temperature and high pressure promotes a tight bond between the ceramic and alloy phase interfaces, achieving densification and structural stability of the composite material.

[0061] Microstructure characterization The microstructure of the sintered composite material was characterized. Figure 4The shell-like composite material successfully prepared by this method is shown. Alumina microsheets are horizontally oriented within the composite material, with the alloy phase uniformly filling the voids between the sheets, forming a tightly bonded ceramic-alloy interface. The density and porosity of the composite material were determined using the Archimedes method.

[0062] The results show that when the alloy content is 20 wt%, the density of the composite material can reach 3.8 g / cm³. 3 Porosity less than 2% Figure 5 This demonstrates excellent densification results and structural integrity.

[0063] Mechanical testing Bending strength reflects the maximum stress a material can withstand under bending loads, and directly indicates its load-bearing capacity in practical applications.

[0064] According to ASTM D7264 standard, for dimensions of 1×3×20 mm... 3 Three-point bending (3PB) tests were performed on strip samples to determine the bending strength of the ceramic composite material. The bending strength was calculated from the maximum load, support span, and sample size.

[0065] The results show that the flexural strength of the composite material first increases and then decreases with increasing alloy content. Among them, the composite material containing 10wt% AlSi10Mg exhibits the highest flexural strength, at 312.2 MPa. Figure 6 ).

[0066] Fracture toughness characterizes a material's resistance to crack propagation and is a key parameter determining the reliability and damage tolerance of composite materials, especially applicable to engineering applications with micro-defects. Following the ASTM E1820 standard, the crack propagation resistance of composite materials with different alloy contents was evaluated using the single-sided notched bending (SENB) test. The crack propagation paths of ceramic composites containing 0 wt%, 10 wt%, 20 wt%, and 40 wt% AlSi10Mg are shown in Figure 7-10.

[0067] The results showed that the cracks in the pure alumina ceramic sample propagated in a straight line, exhibiting typical brittle fracture characteristics, while the cracks in the sample containing 20 wt% AlSi10Mg showed obvious deflection, indicating a significant toughening effect.

[0068] Quantitative analysis using SENB testing showed that when the AlSi10Mg content increased to 20 wt%, the fracture toughness of the composite material reached 13.9 MPa·√m, an improvement of 80.5% compared to pure alumina. This significant toughening effect mainly stemmed from the action of multiple synergistic toughening mechanisms, including crack deflection (…). Figure 12 ), crack bridging ( Figure 13 ), wafer pull-out ( Figure 14 ) and the plastic deformation of alloys ( Figure 15 ).

[0069] The test results above show that the shell-like ceramic composite material prepared by this application through a combination of magnetic field-assisted slurry casting (MASC) and spark plasma sintering (SPS) achieves both high strength and high fracture toughness. Among them, the alumina ceramic composite material containing 20 wt% AlSi10Mg exhibits the best comprehensive mechanical properties, effectively solving the technical challenge of balancing strength and toughness in traditional structural ceramics. This composite material possesses excellent load-bearing capacity and damage resistance, making it suitable for high-performance structural components and advanced engineering applications in harsh service environments.

[0070] The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of the invention or exceeding the scope defined by the appended claims.

Claims

1. A method for preparing a shell-like ceramic composite material, characterized in that, Includes the following steps: (S.1) Provide a slurry comprising ceramic particles and metal alloy particles that have been surface-functionalized to have magnetic responsiveness; (S.2) The particles in the slurry are oriented and aligned under a rotating magnetic field by magnetic field-assisted slurry injection molding to form a green embryo with a layered structure; (S.3) The green embryo is subjected to spark plasma sintering to obtain a dense shell-like ceramic composite material.

2. The preparation method according to claim 1, characterized in that, The ceramic particles are alumina micron flakes, and the metal alloy particles are aluminum-silicon alloy particles.

3. The preparation method according to claim 2, characterized in that, The aluminum-silicon alloy is an AlSi10Mg alloy.

4. The preparation method according to claim 1, characterized in that, The slurry also contains a dispersant, which is anhydrous ethanol.

5. The preparation method according to claim 1, characterized in that, In the magnetic field-assisted grouting molding, the strength of the rotating magnetic field is 5-20 mT.

6. The preparation method according to claim 1, characterized in that, The discharge plasma sintering is carried out in a vacuum environment, with a sintering temperature of 1000-1400℃, a pressure of 30-50MPa, and a holding time of 20-40 minutes.

7. The preparation method according to claim 1, characterized in that, The surface functionalization includes the adsorption of superparamagnetic iron oxide nanoparticles.

8. The preparation method according to claim 1, characterized in that, The metal alloy particles are formed into a sheet-like structure through ball milling.

9. A shell-like ceramic composite material, characterized in that, It is prepared by the method described in any one of claims 1-9; The composite material has a layered structure with alternating ceramic and metal alloy phases, and its fracture toughness is not less than 10 MPa·√m.

10. The application of the shell-like ceramic composite material as described in claim 9 in artificial joints, bone repair materials, or aerospace structural components.

Images