Metal matrix composite material with macro-micro multi-level alternating structure and preparation method thereof

Abstract

This invention relates to the field of composite material technology and provides a metal matrix composite material with a macro- and micro-level alternating structure and its preparation method. The composite material consists of a ceramic phase skeleton and an impregnated metal phase bicontinuous interpenetrating network. Several parallel continuous ceramic lines form the overall skeleton, with gaps between adjacent lines, where the metal phase forms continuous macro-metal channels. Each ceramic line contains oriented short-cut ceramic fibers, which are discontinuously distributed along the axial direction of the ceramic line and overlap to form a porous network with the same orientation. The metal phase impregnates into the pores of the short-cut ceramic fibers, forming a "brick-and-mortar" ordered structure at the micro-level by coating the short-cut ceramic fibers, mimicking the nacreous layer of a seashell. This invention successfully constructs a "macro- and micro-level multi-level biomimetic structure" through advanced control methods of "shear field and freezing field" dual-field coupling, achieving cross-scale synergistic toughening and precise dual-field coupling control.

Description

Technical Field

[0001] This invention belongs to the field of composite material technology, and particularly relates to metal matrix composite materials with macro- and micro-level alternating structures and their preparation methods. Background Technology

[0002] The performance of high-performance impact-resistant materials directly determines the technological ceiling in key fields such as aerospace and high-speed transportation. Currently, carbon fiber / resin engineering protective materials, represented by laminated, cellular, or sandwich structures, despite continuous optimization, still cannot escape the inherent physical law of the "strength-toughness" trade-off and the persistent problem of interlaminar failure. Metal matrix composites, which should be the ideal carrier for combining the rigidity of ceramics and the toughness of metals, have not yet fully realized their theoretical potential under the traditional "uniform dispersion" preparation paradigm. Therefore, breaking through the physical constraints of the difficulty in synergistically achieving lightweight, high strength and wide-velocity impact resistance is an essential hurdle to overcome in the development of next-generation materials for extreme environment service.

[0003] Through a long process of natural evolution, the biological world has developed a series of natural composite materials that combine high strength and high toughness, providing excellent biomimetic models for the design of high-performance impact-resistant materials. Among them, nacre, with its classic "brick-and-mortar" structure, achieves outstanding static fracture toughness and strength through the orderly alternation of hard inorganic phases and soft organic matrices, inducing crack deflection, bridging, and pull-out mechanisms. Meanwhile, the peacock mantis shrimp demonstrates another survival wisdom; its chelipeds form a rotating, stacked Bouligand spiral structure, endowing the material with excellent isotropic damage tolerance and dynamic impact resistance. Both perfectly exemplify nature's ultimate optimization strategies for material performance in the dimensions of "microscopic layered toughening" and "macroscopic spiral impact resistance," respectively.

[0004] While biomimetic technology can now successfully replicate the aforementioned configuration, the performance limitations of "single-scale imitation" are becoming increasingly apparent when facing complex service environments.

[0005] Taking cryogenically cast shell-like materials (E. Munch et al., Science, 2008, 322(5907):1516–1520) as an example, although they exhibit excellent toughness along the layered direction, they are limited by a single cold source, resulting in severe anisotropy in the microstructure. They are prone to translaminar fracture in the direction perpendicular to the layers and lack dynamic impact resistance. On the other hand, the Bouligand-like structures constructed by stacking or 3D printing (D. Ginzburg et al., Composites Science and Technology, 2017, 147: 134-142), although significantly improving impact resistance through macroscopic helices, lack a microscale "brick-and-mortar" interface mechanism, making it difficult for their local static strength and stiffness to match those of tightly packed shell-like structures.

[0006] In addition, taking interpenetrating network structure metal-ceramic composites (Wu Yifeng, et al., Acta Materiae Compositae Sinica, 2025, 42(12).) as an example, although its preparation process achieves dual continuous interpenetration of the metal phase and ceramic phase at both macroscopic and microscopic scales, its microscopic skeleton structure is essentially random and disordered. Due to the lack of orientation design at the microscopic level, this type of material is still limited to physical interpenetration in a single dimension at the structural level and has failed to form a cross-scale synergistic toughening mechanism. Therefore, it is essentially still in the category of "single-level structure".

[0007] Therefore, the key to breaking through the bottleneck lies in achieving cross-scale coupling between "microscopic toughness" and "macroscopic shock resistance." However, translating this design concept into physical materials is hindered by the manufacturing paradox of the difficulty in simultaneously achieving "geometric complexity" and "microscopic order" in existing processes, for example:

[0008] Traditional cryogenic casting suffers from "limited geometrical freedom": It is extremely difficult to construct complex Bouligand helical configurations on a macroscopic scale using traditional cryogenic casting. Even when using multi-step methods or external field-assisted techniques (ZQ Liu et al., ActaBiomaterialia, 2016, 44: 31–40.), it faces problems such as complex equipment systems, limited sample size, and the tendency for fine structures to collapse during the sintering process, which cannot meet the needs of engineering preparation.

[0009] The "rheological paradox" based on single DIW: The fiber arrangement dynamics within the slurry during the DIW process show that fiber orientation can only be induced when the shear stress within the nozzle exceeds the yield stress of the slurry (Michael K, et al. ACS Nano 2018, 12, 6926−6937.). For conventional high-solids-content slurries, there is a significant "choke zone" at the center of the nozzle, where the shear rate is zero and the fibers are in a disordered state. If the viscosity is reduced to pursue the orientation effect of the shear flow field, the wet preform will collapse instantaneously due to insufficient yield strength, and it will be unable to support complex spiral or suspended structures.

[0010] The problem of "single temperature field" in cryogenic printing molding devices: Lin Jinxin (Chinese patent application number: CN118219553A) et al. developed a cryogenic molding device based on low temperature fluid circulation. However, this technology essentially places the molding module in a cryogenic chamber with a uniform temperature, which makes it difficult to induce the directional solidification of ice crystals. Therefore, the problem of the microscopic directional arrangement of fibers remains unsolved.

[0011] In summary, there is still a lack of cross-scale manufacturing methods that can simultaneously achieve "macroscopic complex configurations" and "microscopic ordered orientations". Traditional methods result in a separation between macroscopic and microscopic structures, making it impossible to achieve effective stress transfer between different scales. This limits the performance of metal matrix composites under extreme conditions, and there is an urgent need to develop a preparation technology that can precisely control the synergistic effect of multi-level structures. Summary of the Invention

[0012] The purpose of this invention is to provide a metal matrix composite material with a macro-micro multi-level alternating structure, in order to solve the problems mentioned in the background art.

[0013] The present invention is implemented as follows: a metal matrix composite material with a macro-micro multi-level alternating structure, wherein the metal matrix composite material is composed of a ceramic phase skeleton and an impregnated metal phase bicontinuous interpenetrating network;

[0014] On a macroscopic scale, several parallel and continuous ceramic lines constitute the ceramic phase skeleton, with gaps between adjacent lines, and the metallic phase forms continuous macroscopic metallic channels in the gaps.

[0015] At the microscale, each ceramic line contains oriented short ceramic fibers. The short ceramic fibers are discontinuously distributed along the axial direction of the ceramic line, and the fibers overlap to form a porous network with the same orientation. The metallic phase is infiltrated into the pores of the short ceramic fibers. At the micro level, the short ceramic fibers are coated to form a "brick-and-mortar" ordered structure that mimics the nacreous layer of a shell.

[0016] The metal matrix composite material is composed of multiple structural layers stacked along the thickness direction. The arrangement direction of the continuous ceramic lines in adjacent structural layers rotates according to a preset interlayer deflection angle, which is 0°-90°, so that the metal matrix composite material as a whole forms a Brigand spiral configuration. The orientation direction of the chopped ceramic fibers is parallel to the macroscopic extension direction of the ceramic lines in which they are located, and they deflect synchronously with the rotation of the structural layers, so that a cross-scale helical anisotropic structure is formed inside the metal matrix composite material.

[0017] Another objective of this invention is to provide a method for preparing a metal-based composite material with a multi-level alternating macro- and micro-scale structure, comprising the following steps:

[0018] (1) Preparation of shear-thinning type water-based ceramic ink for cryogenic printing: Short-cut ceramic fibers, dispersant, binder, sintering aid and deionized water are mixed and ball-milled to prepare water-based ceramic ink with shear-thinning properties and viscoelasticity;

[0019] (2) Dual-field coupling printing: A direct ink writing system integrating a temperature-controlled freezing platform and a heating device is used to print the ceramic water-based ink on a temperature-controlled low-temperature platform according to a preset path to form continuous ceramic lines; during the printing extrusion process, the rheological shear force field generated by the micro nozzle is used to induce the short-cut ceramic fibers on the periphery of the lines to be initially oriented along the extrusion direction; at the moment of deposition, the low-temperature platform and the heating device are used to induce the generation of a directional temperature gradient field along the line direction, induce the ice crystals to grow directionally along the line direction, and drive the orientation of the fibers inside the lines. After printing layer by layer, a frozen green body with a macroscopic spiral structure and a microscopic fiber orientation structure is obtained.

[0020] (3) Freeze-drying and ultra-fast high-temperature sintering: The frozen green body is freeze-dried in a vacuum environment to allow the ice crystals to sublimate directly to form interconnected pores, and then ultra-fast high-temperature sintering is performed to obtain a rigid ceramic skeleton with hierarchical pores.

[0021] (4) Vacuum pressure infiltration: Molten metal liquid is infiltrated into the macroscopic gaps between layers and the microscopic pores between fibers of the rigid ceramic skeleton under pressure, and the metal matrix composite material is obtained after cooling.

[0022] This invention provides an advanced control method that couples a shear field and a freezing field, successfully constructing a macro-micro multi-level biomimetic structure:

[0023] At the macro level: It breaks through the disordered stacking of traditional interpenetrating networks and constructs a Bouligand-like spiral configuration that can hinder the linear propagation of cracks;

[0024] At the microscopic level: within each layer of ceramic lines, the dual-field coupling effect induces short-cut ceramic fibers to achieve highly oriented arrangement. This oriented overlapping fiber network constitutes the "bricks" (reinforcing skeleton) in the biomimetic structure, while the metallic phase filling the oriented pores constitutes the "mud" (tough matrix).

[0025] As can be seen, the embodiments of the present invention have truly realized the preparation of multi-scale, multi-level structured metal matrix composites by organically combining macroscopic spirals with microscopic "brick-and-mortar" structures, which is fundamentally different from the disordered interpenetrating structures in the prior art.

[0026] Specifically, it has the following advantages:

[0027] Cross-scale synergistic toughening: A "double continuous interpenetrating network" was constructed, with a macroscopic spiral structure guiding crack twisting and deflection, and microscopic ordered fibers triggering bridging and pull-out mechanisms, which significantly solved the problem of the inversion of strength and toughness in ceramic matrix composites;

[0028] Dual-field coupling control precision: By utilizing the synergistic effect of extrusion shearing and freezing phase change, dynamic induction and in-situ locking of micro-fiber orientation are achieved, breaking through the technical limitation of traditional 3D printing fiber orientation being difficult to maintain. Attached Figure Description

[0029] Figure 1 A flowchart illustrating the preparation process of a metal matrix composite material with a multi-level alternating macro- and micro-scale structure, provided in an embodiment of the present invention.

[0030] Figure 2 The images are SEM images of the macroscopic structure and microscopic structure of the ceramic scaffold provided in Embodiment 1 of the present invention. a1 is the macroscopic appearance of the multi-level structure ceramic preform, a2 is its local macroscopic SEM image, a3 is the microscopic SEM image of the multi-level structure ceramic preform, and a4 is its microstructure SEM image.

[0031] Figure 3 The energy dispersive spectroscopy (EDS) analysis diagram of the interfacial region of the Al / mullite composite material prepared in Example 1 of this invention is shown.

[0032] Figure 4 Bending stress-strain curves of Al / mullite fiber composites with different rotation angles provided in embodiments of the present invention;

[0033] Figure 5 Impact stress-strain curves of Al / mullite fiber composite materials with different rotation angles provided in embodiments of the present invention. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0035] The specific implementation of the present invention will be described in detail below with reference to specific embodiments.

[0036] Example 1: Al / mullite composite material 3D printed using a controlled cryogenic platform for direct ink writing (DIW). The preparation process is as follows: Figure 1 As shown, the specific process includes:

[0037] (1) Preparation of ceramic ink: The ink formulation is as follows: 0.4 vol% of binder sodium carboxymethyl cellulose (CMC-Na), 0.45 vol% of dispersant polyethylene glycol (PEG-6000), 30 vol% of mullite fiber, 4 vol% of TiO2 sintering aid, and the balance is deionized water. In this ink system, the binder CMC-Na mainly undertakes the functions of structural bonding and network construction, while the dispersant PEG-6000 achieves stable fiber dispersion through steric hindrance. The two work together to ensure uniform fiber dispersion while improving the structural stability and forming controllability of the slurry, laying the foundation for the precise preparation of multi-level structure ceramic skeletons. The raw materials are ball-milled and mixed. The ball milling process is as follows: ball milling is performed intermittently at a speed of 1000-3000 r / min for 25 min at a temperature of 30 ℃. After the above process, ceramic fiber ink suitable for dual-field coupling printing is obtained.

[0038] (2) The direct ink writing system with integrated controllable freezing platform and heating device is configured as follows: The 3D printer reads and parses the printing driver program, and precisely controls the nozzle to move along the preset imitation Brigand spiral path according to the interlayer rotation angle and stacking rate parameters set in the program; one end of the air pressure controller is connected to a high-precision air pump, and the other end is connected to the loading cylinder, which is used to provide constant pneumatic pressure to drive the extrusion of high viscoelastic ink; the heating device is the outer sleeve of the loading cylinder, which is used to prevent the extruded lines from solidifying and clogging the needle when they come into contact with the freezing platform below, and it works with the bottom freezing platform to regulate the temperature gradient on the lines to promote the directional growth of ice crystals to drive the orientation of the fibers inside the lines; the controllable freezing platform is located below the nozzle and consists of a semiconductor cooling component, a heat dissipation component and a PID temperature control device; the platform is configured to provide a constant cold source background during the low temperature deposition printing process, wherein the semiconductor cooling component provides the cooling capacity, the heat dissipation component is used to quickly remove heat to maintain the cooling efficiency, and the PID temperature control device is used to precisely maintain the surface temperature of the platform at the preset low temperature set point, so as to ensure that the temperature field can better work in conjunction with the needle shear force field to construct the microstructure inside the ceramic lines;

[0039] (3) Ceramic ink is added to the 3D printer. During the printing process, the nozzle moves along the preset imitation Brigand spiral path to construct the macroscopic structure. At the same time, by adjusting the matching relationship between the extrusion speed of the slurry and the printing speed of the platform, the rheological shear force field generated by the micro needle is used to force the ceramic fibers to undergo primary orientation along the printing path. Then, the power of the freezing platform is adjusted, and the freezing platform and heating device are used to establish an orientation temperature gradient inside the ceramic lines to further push and assemble the already oriented fibers, so that the orientation of the fibers is smoother. The printing parameters are: platform printing speed: 3 mm / s; extrusion air pressure: 1.5 atm; controllable freezing platform temperature range: -20 ℃; spiral angle: 30°, to obtain a ceramic skeleton green body.

[0040] (4) The printed ceramic skeleton green body is placed into a freeze dryer and the parameters of the freeze dryer are set to a temperature of -49 ℃. The pressure in the freeze dryer is pumped down to 200 Pa by a mechanical pump. In the low pressure and low temperature environment, the moisture in the ceramic skeleton is removed by sublimation to obtain a multi-level structured ceramic skeleton.

[0041] (5) The freeze-dried ceramic skeleton blank is then placed into an ultra-fast sintering furnace to remove organic matter from the ceramic skeleton and improve its strength. This stage is carried out in a multi-process environment.

[0042] The heating rate is 400 ℃ / min, and the maximum sintering temperature is 1450 ℃;

[0043] The temperature was reduced to room temperature at a rate of 10 °C / min, thus completing the degreasing and sintering stage.

[0044] To obtain a multi-level ceramic framework with good strength, such as Figure 2 As shown in a1 and a2, the overall structure of the ceramic skeleton is complete, and from Figure 2 As can be seen from a3 and a4, the prepared ceramic skeleton has a multi-level structure that imitates Brigand macroscopically and “brick-mud” microscopically, demonstrating the feasibility of the above process.

[0045] (6) Finally, the sintered ceramic blank and pure aluminum are placed in a pressure infiltration furnace. The infiltration process is as follows:

[0046] First, the temperature was raised to 250 °C at a rate of 3 °C / min and held for a period of time. Then, the temperature was raised to a maximum of 900 °C to melt the pure aluminum. The temperature was then lowered to 760 °C at a rate of 8 °C / min, and high-purity argon gas at 3.5 MPa was introduced to completely fill the pores of the preform with molten aluminum, thus preparing the Al / mullite fiber metal matrix ceramic composite material. Next, the temperature was lowered to room temperature at a rate of 8 °C / min, specifically between 600 °C and 760 °C, followed by a cooling rate of 3 °C / min to room temperature, finally producing the composite material. All of the above processes were carried out under high vacuum (10... -2 Performed under (Pa).

[0047] The composite material prepared in Example 1 was characterized and its performance was tested: the EDS energy dispersive spectroscopy analysis results are as follows: Figure 3 As shown, this indicates the uniform distribution and purity of the Al and mullite fibrous phases; the results of the three-point bending strength test are as follows. Figure 4 As shown, the composite material exhibits excellent synergy between strength and toughness; in addition, impact resistance tests were conducted on the composite material, and the results are as follows. Figure 5 As shown in the figure, the composite material has good impact resistance and achieves a combination of strength and toughness.

[0048] Example 2: Al / SiC fiber composite material 3D printed using a controlled cryogenic platform for direct ink writing (DIW). The specific process includes:

[0049] (1) Preparation of SiC fiber ceramic ink: Dispersant, binder, silicon carbide fiber and deionized water were weighed and ball-milled to obtain SiC fiber ceramic ink suitable for freeze printing. The proportions are as follows (based on a total volume of 100 vol%): Binder: 0.35 vol% hydroxypropyl methylcellulose (HPMC), dispersant: 0.6 vol% polyethylene glycol (PEG-6000), silicon carbide fiber: 25 vol%, with the remainder being deionized water; Ball milling process parameters: ball milling was performed intermittently at 1800 r / min for 25 min at 35 ℃ to obtain SiC fiber ceramic ink with good rheological properties and freeze-response characteristics.

[0050] The freeze printing, freeze drying, degreasing sintering and ultra-fast sintering processes in steps (2)-(5) are consistent with those in Example 1;

[0051] (6) Metal pressure infiltration:

[0052] The sintered SiC fiber ceramic skeleton was placed in a pressure infiltration furnace under high vacuum (10). -2Under the following conditions: the temperature was increased to 300 °C at a heating rate of 5 °C / min for pretreatment; then the temperature was increased to the maximum temperature at a heating rate of 5-10 °C / min, and then 4 MPa of high-purity Ar gas was introduced when the temperature was cooled to 780 °C to allow the molten aluminum liquid to fully impregnate the pores; then the temperature was cooled to room temperature at 5 °C / min to prepare SiC fiber / Al composite material.

[0053] Example 3: Al / alumina fiber composite material for direct ink writing (DIW) 3D printing on a controlled cryogenic platform, the specific process includes:

[0054] (1) Preparation of Al2O3 fiber ceramic ink:

[0055] Dispersant, binder, alumina fiber, deionized water, and sintering aid were weighed and ball-milled to obtain Al2O3 fiber ceramic ink suitable for cryogenic printing. The formulation is as follows (based on a total volume of 100 vol%): binder: 0.4 vol% sodium alginate, dispersant: 0.5 vol% Pronic, alumina fiber: 30 vol%, sintering aid: 3 vol% ZrO2, with the balance being deionized water. Sodium alginate forms a continuous three-dimensional network structure in water, giving the slurry good thixotropic properties and forming stability. Pronic forms a stable steric hindrance layer on the fiber surface through its PEO-PPO-PEO triblock structure, effectively inhibiting fiber aggregation and giving the ink good shear thinning behavior and forming stability. In addition, it has good synergy with the cryogenic forming process, which is beneficial to the construction and maintenance of multi-level pore structures. Ball milling conditions: ball milling at 2000 r / min for 20 min at a temperature of 35 ℃.

[0056] The freeze printing, freeze drying, degreasing sintering, ultra-fast sintering and pressure infiltration processes in steps (2)-(6) are consistent with those in Example 1;

[0057] Example 4: Printing Al / mullite fiber composite material with a helical angle of 3.75° using a controlled-cryogenic platform direct ink writing (DIW) 3D printing device;

[0058] Steps (1)-(2) for ceramic ink preparation and cryogenic printing are consistent with those in Example 1;

[0059] (3) Ink is added to the printing device. During the printing process, the nozzle moves along the preset imitation Brigand spiral path to construct the macroscopic structure. At the same time, by adjusting the matching relationship between the extrusion speed of the slurry and the printing speed of the platform, the rheological shear force field generated by the micro needle is used to force the ceramic fibers to undergo primary orientation along the printing path. Then, the power of the freezing platform is adjusted, and the freezing platform and heating device are used to establish an orientation temperature gradient inside the ceramic lines to further push and assemble the already oriented fibers, so that the orientation of the fibers is smoother. The printing parameters are: platform printing speed: 3 mm / s; extrusion air pressure: 1.5 atm; controllable freezing platform temperature range: -20 ℃; spiral angle: 3.75°, to obtain the ceramic skeleton green body.

[0060] Steps (4)-(6) of freeze drying, ultra-fast sintering and pressure infiltration processes are consistent with those in Example 1.

[0061] Example 5: Printing Al / mullite fiber composite material with a helical angle of 7.5° using a controlled-cryogenic platform direct ink writing (DIW) 3D printing device:

[0062] Steps (1)-(2) for ceramic ink preparation and cryogenic printing are consistent with those in Example 1;

[0063] (3) Ink is added to the printing device. During the printing process, the nozzle moves along the preset imitation Brigand spiral path to construct the macroscopic configuration. At the same time, by adjusting the matching relationship between the extrusion speed of the slurry and the printing speed of the platform, the rheological shear force field generated by the micro needle is used to force the ceramic fibers to undergo primary orientation along the printing path. Then, the power of the freezing platform is adjusted, and the freezing platform and heating device are used to establish an orientation temperature gradient inside the ceramic lines to further push and assemble the already oriented fibers, so that the orientation of the fibers is smoother. The printing parameters are: platform printing speed: 3 mm / s; extrusion air pressure: 1.5 atm; controllable freezing platform temperature range: -20 ℃; spiral angle: 7.5°.

[0064] Steps (4)-(6) of freeze drying, ultra-fast sintering and pressure infiltration processes are consistent with those in Example 1.

[0065] Example 6: Printing of aluminum alloy (model: ZL205A) / mullite fiber composite material using a controlled-cryogenic platform direct ink writing (DIW) 3D printing device:

[0066] Steps (1)-(5) are consistent with those in Example 1;

[0067] (6) The sintered ceramic blank and aluminum alloy are placed in a pressure infiltration furnace. The infiltration process is as follows:

[0068] The procedure is as follows: First, the temperature is increased to 250℃ at a rate of 4℃ / min, held for a period of time, then increased to the maximum temperature of 950℃. While waiting for the temperature to drop to 850℃ at a rate of 5℃ / min, high-purity argon gas at 3 MPa is introduced to completely fill the pores of the billet with molten aluminum, thus preparing the aluminum alloy (model: ZL205A) / mullite cermet composite material. Next, the temperature is reduced to room temperature at a rate of 8℃ / min, finally producing the composite material. All of the above processes are carried out under high vacuum (10... -2 Performed under (Pa).

[0069] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A metal matrix composite material with a multi-level alternating macro- and micro-scale structure, characterized in that, The metal matrix composite material is composed of a ceramic phase skeleton and an impregnated metal phase bicontinuous interpenetrating network; On a macroscopic scale, several parallel and continuous ceramic lines constitute the ceramic phase skeleton, with gaps between adjacent lines, and the metallic phase forms continuous macroscopic metallic channels in the gaps. At the microscale, each ceramic line contains oriented short ceramic fibers. The short ceramic fibers are discontinuously distributed along the axial direction of the ceramic line, and the fibers overlap to form a porous network with the same orientation. The metallic phase is infiltrated into the pores of the short ceramic fibers. At the micro level, the short ceramic fibers are coated to form a "brick-and-mortar" ordered structure that mimics the nacreous layer of a shell. The metal matrix composite material is composed of multiple structural layers stacked along the thickness direction. The arrangement direction of the continuous ceramic lines in adjacent structural layers rotates according to a preset interlayer deflection angle, which is 0°-90°, so that the metal matrix composite material as a whole forms a Brigand spiral configuration. The orientation direction of the chopped ceramic fibers is parallel to the macroscopic extension direction of the ceramic lines in which they are located, and they deflect synchronously with the rotation of the structural layers, so that a cross-scale helical anisotropic structure is formed inside the metal matrix composite material.

2. The metal matrix composite material with a multi-level alternating macro- and micro-scale structure according to claim 1, characterized in that, The volume fraction of the ceramic phase framework is 20-30 vol.

3. The metal matrix composite material with a multi-level alternating macro- and micro-scale structure according to claim 1, characterized in that, The chopped ceramic fiber is at least one of mullite fiber, alumina fiber, and silicon carbide fiber.

4. The metal matrix composite material with a multi-level alternating macro- and micro-scale structure according to claim 1, characterized in that, The interlayer deflection angle varies linearly or nonlinearly along the thickness direction.

5. A method for preparing a metal matrix composite material with a multi-level alternating macro- and micro-scale structure as described in any one of claims 1-4, characterized in that, Includes the following steps: (1) Preparation of shear-thinning type water-based ceramic ink for cryogenic printing: Short-cut ceramic fibers, dispersant, binder, sintering aid and deionized water are mixed and ball-milled to prepare water-based ceramic ink with shear-thinning properties and viscoelasticity; (2) Dual-field coupling printing: A direct ink writing system with an integrated temperature-controlled freezing platform and heating device is used to print the ceramic water-based ink on a temperature-controlled low-temperature platform according to a preset path to form continuous ceramic lines; During the printing extrusion process, the rheological shear force field generated by the micro nozzle is used to induce the initial orientation of the short ceramic fibers on the outer periphery of the line along the extrusion direction. At the moment of deposition, the low temperature platform and heating device are used to induce the generation of an oriented temperature gradient field along the line direction, which induces the oriented growth of ice crystals along the line direction and drives the orientation of the fibers inside the line. After printing layer by layer, a frozen green body with a macroscopic spiral structure and a microscopic fiber orientation structure is obtained. (3) Freeze-drying and ultra-fast high-temperature sintering: The frozen green body is freeze-dried in a vacuum environment to allow the ice crystals to sublimate directly to form interconnected pores, and then ultra-fast high-temperature sintering is performed to obtain a rigid ceramic skeleton with hierarchical pores. (4) Vacuum pressure infiltration: Molten metal liquid is infiltrated into the macroscopic gaps between layers and the microscopic pores between fibers of the rigid ceramic skeleton under pressure, and the metal matrix composite material is obtained after cooling.

6. The method for preparing a metal matrix composite material with a multi-level alternating macro- and micro-scale structure according to claim 5, characterized in that, In step (1), the ceramic water-based ink comprises the following raw materials by volume percentage: dispersant 0.4-0.9 vol%, binder 0.15-0.45 vol%, ceramic fiber 20-30 vol%, sintering aid 0.5-4 vol%, and the balance being deionized water; The dispersant is at least one of polyacrylamide, polyethylene glycol, and Pluronic acid; The binder is at least one of sodium carboxymethyl cellulose, sodium alginate, and hydroxypropyl methyl cellulose; The chopped ceramic fibers have a length of 50-500 μm and an aspect ratio of 10-30.

7. The method for preparing a metal matrix composite material with a macro-microscopic multi-level alternating structure according to claim 5, characterized in that, In step (2), the direct ink writing system integrating a temperature-controlled freezing platform and a heating device includes: A 3D printer used to read the print driver and control the nozzle to move along a preset spiral path; The pneumatic controller, connected to an air pump at one end and a feeding cylinder at the other end, is used to provide constant pneumatic pressure to drive ink extrusion. The cylinder is fitted with a heating sleeve to prevent the extruded lines from solidifying and clogging the needles when they come into contact with the controllable freezing platform. It works in conjunction with the controllable freezing platform to regulate the temperature gradient on the lines to promote the directional growth of ice crystals and drive the orientation of the fibers inside the lines. The controllable freezing platform located below the printhead consists of a semiconductor cooling component, a heat dissipation component, and a PID temperature control device. It is used to provide a constant cold source and maintain the surface temperature at a preset low temperature during the low-temperature deposition printing process.

8. The method for preparing a metal matrix composite material with a macro-microscopic multi-level alternating structure according to claim 5, characterized in that, In step (2), the temperature of the cryogenic platform is -10 ℃ to -40 ℃; The extrusion pressure during printing is 0.5-3 atm, and the printing speed is 2-8 mm / s.

9. The method for preparing a metal matrix composite material with a macro-microscopic multi-level alternating structure according to claim 5, characterized in that, In step (3), the vacuum degree of the freeze-drying is 50-300 Pa; The specific operation of the ultra-fast high-temperature sintering is as follows: the sample is placed between graphite felts heated by Joule, and the heating rate is 100-500 ℃ / min by adjusting the magnitude and rate of increase of the current applied to the felts, and the maximum sintering temperature is 1300-1550 ℃.

10. The method for preparing a metal matrix composite material with a macro-microscopic multi-level alternating structure according to claim 5, characterized in that, In step (4), the impregnation temperature is 760-950 ℃ and the impregnation pressure is 3-8 MPa.

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