A Mo ≤5 Si ≤3 C ≤1 Basalt composite ceramic material and preparation method and application thereof

Abstract

The application relates to a Mo ≤5 Si ≤3 C ≤1 / Basalt composite ceramic material and a preparation method and application thereof, and belongs to the technical field of inorganic nonmetallic materials. ≤5 Si ≤3 C ≤1 / Basalt composite ceramic material is prepared by taking Mo powder, Si powder, graphite powder and basalt powder as raw materials, wherein the adding amount of the basalt powder is 5% to 30% of the mass of Mo ≤5 Si ≤3 C ≤1 . The application remarkably improves the fracture toughness of the material by introducing natural basalt particles into the MoSiC matrix, and forms a glass phase protective layer by using the basalt component at high temperature, so that the material is endowed with excellent cyclic oxidation resistance and high-temperature friction-reducing wear resistance. The material can be used as a structure-function integrated high-performance ceramic, and is applied to high-temperature structural parts with melting resistance, wear resistance and oxidation resistance under extreme working conditions such as aerospace, energy equipment and high-end machinery. The method is simple in process, low in cost and easy to mass produce.

Description

Technical Field

[0001] This invention belongs to the field of inorganic non-metal preparation technology, and particularly relates to a Mo ≤5 Si ≤3 C ≤1 Basalt composite ceramic materials, their preparation methods, and applications belong to the field of high-temperature oxidation-resistant and wear-resistant ceramic materials. They are specifically applied to structural and functional integrated materials under extreme working conditions such as aerospace, energy equipment, and high-end machinery. Background Technology

[0002] With the rapid development of aerospace, energy equipment, and high-end manufacturing, the service requirements of equipment under extreme conditions such as high temperature, high load, and high friction are constantly increasing, placing higher demands on the wear resistance, high temperature resistance, and self-lubricating properties of structural materials. While traditional metallic materials possess high strength and toughness, they are prone to oxidation, accelerated wear, and decreased lubrication performance under high-temperature environments, making it difficult to meet the requirements for long-term stable operation. Therefore, developing high-performance ceramic or cermet materials that combine structural strength and functional properties has become an important research direction in the field of materials science.

[0003] MoSiC-based ceramic materials have attracted widespread attention in the fields of wear-resistant materials and high-temperature structural materials due to their excellent high-temperature stability, good oxidation resistance, and high hardness. However, traditional MoSiC-based ceramics have some shortcomings, such as low toughness and insufficient stability of tribological properties under complex working conditions, which limits their further application in extreme environments. Basalt is a natural inorganic mineral material, mainly composed of various silicate minerals, and has good heat resistance, chemical stability, and high hardness and wear resistance. At the same time, basalt is abundant and inexpensive, making it a promising candidate for use in ceramic composite materials. Introducing basalt powder into ceramic matrix composites can improve the material's structural density, thermal shock resistance, and wear resistance to a certain extent.

[0004] However, the introduction of basalt powder as a functional phase into MoSiC-based metal-ceramic systems, leveraging its unique mineral composition (rich in SiO2, Al2O3, Fe2O3, etc.) and the potential synergistic effects with the matrix to develop novel composite materials possessing excellent high-temperature strength, oxidation resistance, and solid lubrication properties, has not yet been reported in existing technologies. In summary, there is a lack of a simple composite method that effectively combines the high-temperature load-bearing capacity of MoSiC with the wear resistance and friction-regulating properties of basalt. This invention aims to fill this gap and is of great significance for expanding the application of such materials in extreme environments such as high-temperature and high-load conditions. Summary of the Invention

[0005] This invention provides a Mo ≤5 Si ≤3 C ≤1 This study aims to address the problems of low fracture toughness, severe mass loss under high-temperature cyclic oxidation, and insufficient high-temperature friction and wear resistance in existing MoSiC phase ceramic materials. It also provides a simple, low-cost preparation method for rapid densification, and the application of this material in high-temperature structural components that are resistant to melting, wear, and oxidation.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: First, the present invention provides a Mo ≤5 Si ≤3 C ≤1 / Basalt composite ceramic material, the composite material being composed of Mo ≤5 Si ≤3 C ≤1 The structure consists of a ceramic matrix and basalt particles uniformly dispersed within the matrix; the mass of the basalt particles is the Mo. ≤5 Si ≤3 C ≤1 5% to 30% of the ceramic matrix mass.

[0007] As a preferred technical solution, the mass of the basalt particles is the Mo ≤5 Si ≤3 C ≤1 5% of the mass of the ceramic matrix.

[0008] Furthermore, the Mo ≤5 Si ≤3 C ≤1 The ceramic matrix is ​​generated by in-situ reaction of Mo powder, Si powder and graphite powder during high-temperature sintering.

[0009] Furthermore, the basalt particles have a particle size of 1 μm to 100 μm and a purity of ≥99.9%; the Mo powder, Si powder, and graphite powder have particle sizes of 1 μm to 50 μm and a purity of ≥99.9%, respectively.

[0010] Secondly, the present invention provides the above-mentioned Mo ≤5 Si ≤3 C ≤1 The preparation method of Basalt composite ceramic materials includes the following steps: (1) Weigh out Mo powder, Si powder, and graphite powder according to the molar ratio of Mo, Si, and graphite of (3~5):(2~3):(0.5~1), and weigh out basalt powder, wherein the amount of basalt powder added is the amount of Mo...≤5 Si ≤3 C ≤1 5% to 30% of the ceramic matrix mass; (2) The powder raw materials weighed in step (1) are mixed under an inert atmosphere and then ball-milled to disperse them evenly to obtain a mixed powder. (3) The mixed powder is pressed into a blank to obtain a green body; (4) The green body is sintered at high temperature under vacuum or inert atmosphere to allow Mo, Si and graphite to react in situ to generate Mo. ≤5 Si ≤3 C ≤1 Ceramic matrix, thereby obtaining Mo ≤5 Si ≤3 C ≤1 / Basalt composite ceramic material.

[0011] The method of this invention involves first ball milling and mixing Mo powder, Si powder, graphite powder, and basalt powder, followed by sieving, pressing, and calcination to prepare Mo. ≤5 Si ≤3 C ≤1 / Basalt composite ceramics. This method, in the early stages of powder material preparation, can better optimize Mo compared to existing boron (carbothermic) reduction methods and self-propagating high-temperature synthesis methods. ≤5 Si ≤3 C ≤1 The content of each element in the / Basalt composite ceramic is controlled to avoid introducing excessive other impurities, and the operation process is simple and requires no complicated procedures. This invention uses spark plasma sintering technology to achieve Mo ≤5 Si ≤3 C ≤1 Integrated preparation of Basalt composite ceramics. Compared to traditional processes, this method overcomes the limitations of stepwise powder preparation, pre-firing, pressing, and secondary sintering. It eliminates the need for powder pre-firing and secondary sintering, directly achieving rapid densification of the mixed powder and significantly simplifying the preparation process. This method is simple, low-cost, and greatly reduces time costs. Furthermore, basalt, as a natural inorganic mineral material, is abundant and inexpensive. Through this simple and environmentally friendly preparation process, bulk ceramic materials with excellent mechanical properties, high-temperature oxidation resistance, and tribological properties were obtained, meeting the requirements for safe and reliable service of mechanical components under harsh conditions such as high temperature and high load.

[0012] Secondly, during the spark plasma sintering process, temperature significantly affects the synthesis of Mo. ≤5 Si ≤3 C ≤1The sintering temperature significantly affects the growth of basalt composite ceramics. Under SPS rapid sintering conditions, grain growth is somewhat suppressed, resulting in a fine and uniform microstructure. However, the sintering temperature directly impacts the diffusion rate of the original powder and grain growth. Too low a temperature leads to incomplete sintering and failure to synthesize the target phase, while too high a temperature may cause the basalt components to decompose or react with the MoSiC phase, affecting interfacial bonding. Holding time is a major driving force for grain growth; a suitable holding time promotes densification, but excessively long holding times may lead to abnormal grain growth, potentially causing secondary recrystallization or pore aggregation, thus reducing density and resulting in poor performance. Pressure is a key factor in promoting densification, but excessive pressure may cause mold deformation, internal stress concentration, and even microcracks, impairing mechanical properties.

[0013] As a preferred technical solution, the ball milling in step (2) is a dry ball milling with a rotation speed of 200 r / min to 600 r / min and a milling time of 2 h to 12 h.

[0014] As a preferred technical solution, the pressing pressure in step (3) is 10 MPa to 100 MPa.

[0015] As a preferred technical solution, the high-temperature sintering temperature in step (4) is 1500 ℃~1700 ℃, and the sintering holding time is 10 min~60 min.

[0016] As a preferred technical solution, the high-temperature sintering in step (4) adopts spark plasma sintering, and the vacuum degree during the sintering process is <10. 1 Pa, heating rate of 10 ℃ / min~100 ℃ / min, and pressure gradually increased to 35 MPa while heating to sintering temperature.

[0017] Finally, the present invention provides the above-mentioned Mo ≤5 Si ≤3 C ≤1 Basalt composite ceramic materials are used in the fabrication of high-temperature structural components that are resistant to melting, wear, or oxidation. These high-temperature structural components include, but are not limited to, turbine blades, combustion chamber liners, thermal protection systems, high-temperature furnace components, high-temperature structural parts for aerospace applications, and wear-resistant coatings.

[0018] Compared with the prior art, the Mo provided by the present invention ≤5 Si ≤3 C ≤1 / Basalt composite ceramic materials, their preparation methods, and applications, through Mo ≤5 Si ≤3 C ≤1Introducing natural basalt particles into the ceramic matrix as a reinforcing phase significantly improves the fracture toughness of the material. Experiments show that the fracture toughness can reach 3.96 ± 0.12 MPa·m when 5 wt.% basalt is added. 1 / 2 Compared to the matrix material without added basalt (1.3 MPa·m 1 / 2 The fracture toughness was improved by 67.2%, effectively overcoming the Mo... ≤5 Si ≤3 C ≤1 The inherent brittleness of ceramics.

[0019] Secondly, this composite material exhibits excellent resistance to cyclic oxidation under high-temperature oxidizing conditions. The SiO2, Al2O3, and Fe2O3 components abundant in the basalt can form a low-viscosity, flowable, dense glassy protective layer in situ, rapidly covering the material surface and filling micro-defects, thereby isolating oxygen diffusion into the matrix. In a 1000 ℃ cyclic oxidation test, its mass loss is significantly reduced compared to the pure phase material, and the oxidation kinetics change from a parabolic to a more stable near-linear type. This material also possesses excellent high-temperature tribological properties. In a 1000 ℃ high-temperature reciprocating friction and wear test, the average friction coefficient of the 5 wt.% Basalt composite ceramic is 0.516, and the wear rate is as low as 3.3 × 10⁻⁶. -5 mm 3 / (N·m), compared to pure Mo ≤5 Si ≤3 C ≤1 The material exhibits stable and excellent high-temperature friction reduction and wear resistance properties, with a 7.2% reduction in the coefficient of friction and an order of magnitude reduction in the wear rate.

[0020] Furthermore, the basalt used in this invention is a natural inorganic mineral, widely available and inexpensive. The preparation process requires no pre-firing or secondary sintering, is simple, has a short cycle time, low energy consumption, and is easily scalable for mass production. In summary, the material of this invention possesses high hardness, high fracture toughness, high-temperature oxidation resistance, and high-temperature self-lubricating wear resistance, making it a suitable next-generation structural-functional integrated high-performance material to meet the application requirements of aerospace, energy equipment, and high-end machinery under extreme working conditions. Attached Figure Description

[0021] Figure 1 Mo prepared in Example 1 of this invention ≤5 Si ≤3 C ≤1 X-ray diffraction (XRD) pattern of a 5wt.% Basalt composite ceramic material.

[0022] Figure 2 Mo prepared in Example 1 of this invention ≤5 Si ≤3 C ≤1Scanning electron microscope (SEM) image of a 5wt.% Basalt composite ceramic material.

[0023] Figure 3 Mo prepared in Example 1 of this invention ≤5 Si ≤3 C ≤1 Energy dispersive spectroscopy (EDS) elemental distribution of 5wt.% Basalt composite ceramic material.

[0024] Figure 4 Mo prepared in Examples 1-6 of this invention with different basalt addition amounts (0 wt.%, 5 wt.%, 10 wt.%, 15 wt.%, 20 wt.%, 30 wt.%) ≤5 Si ≤3 C ≤1 Photographs of the surface morphology and oxidation weight gain curves of the / Basalt composite ceramic material after cyclic oxidation at 1000 ℃ for 60 min, 120 min and 180 min.

[0025] Figure 5 Mo prepared in Examples 1-6 of this invention with different basalt addition amounts (0 wt.%, 5 wt.%, 10 wt.%, 15 wt.%, 20 wt.%, 30 wt.%) ≤5 Si ≤3 C ≤1 Figure showing the mass change of a Basalt composite ceramic material sample after three cycles of oxidation (60 min each time) at 1000 °C.

[0026] Figure 6 Mo prepared in Examples 1-6 of this invention with different basalt addition amounts (0 wt.%, 5 wt.%, 10 wt.%, 15 wt.%, 20 wt.%, 30 wt.%) ≤5 Si ≤3 C ≤1 The average friction coefficient curve and wear rate bar chart of / Basalt composite ceramic material at 1000 ℃. Detailed Implementation

[0027] To make the technical solution and beneficial effects of the present invention clearer, the present invention will be described in detail below with reference to specific embodiments and accompanying drawings. It should be understood that the following embodiments are for illustrative purposes only and do not constitute any limitation on the scope of protection of the present invention. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are included within the scope of protection of the present invention.

[0028] Example 1: Mo ≤5 Si ≤3 C≤1 Preparation of / 5wt.% Basalt composite ceramic materials (1) Mo powder, Si powder, graphite powder with a particle size of 1 μm to 50 μm and a purity of ≥99.9%, and basalt powder with a particle size of 1 μm to 100 μm and a purity of ≥99.9% are used as raw materials. Mo powder, Si powder and graphite powder are weighed according to the molar ratio of Mo, Si and graphite of (3~5):(2~3):(0.5~1), with a preferred ratio of 4.8:3:0.6; wherein the amount of basalt powder added is Mo ≤5 Si ≤3 C ≤1 5% of the ceramic matrix mass. The weighed powder was placed in a tungsten carbide ball mill jar, and cemented carbide balls (ball-to-powder mass ratio 5:1) were added, along with 2 wt.% stearic acid as a dispersant. Under inert gas protection, the mixture was dry-milled at 500 r / min for 10 h to obtain a uniformly mixed powder.

[0029] (2) The mixed powder obtained in step (1) is pre-pressed into a blank by a hydraulic press under a pressure of 30 MPa.

[0030] (3) Place the billet in a spark plasma sintering furnace and evacuate it to a vacuum degree <10. 1 The temperature was increased from room temperature to 1600 °C at a rate of 100 °C / min, while the pressure was gradually and uniformly increased to 35 MPa during the heating process. The furnace was then sintered at 1600 °C and 35 MPa for 15 min, and then allowed to cool naturally to room temperature to obtain Mo. ≤5 Si ≤3 C ≤1 / 5wt.% Basalt composite ceramic material.

[0031] Example 2: Mo ≤5 Si ≤3 C ≤1 Preparation of / 10wt.%Basalt composite ceramic materials This embodiment is basically the same as Embodiment 1, except that the amount of basalt powder added in step (1) is Mo. ≤ 5Si ≤3 C ≤1 10% of the ceramic matrix mass. The remaining raw material ratios, ball milling parameters, pressing parameters, and spark plasma sintering parameters were the same as in Example 1, ultimately yielding Mo. ≤5 Si ≤3 C ≤1 / 10wt.%Basalt composite ceramic material.

[0032] Example 3: Mo ≤5 Si≤3 C ≤1 Preparation of / 15wt.% Basalt composite ceramic materials This embodiment is basically the same as Embodiment 1, except that the amount of basalt powder added in step (1) is Mo. ≤ 5Si ≤3 C ≤1 15% of the ceramic matrix mass. The remaining conditions were the same as in Example 1, yielding Mo. ≤5 Si ≤3 C ≤1 / 15wt.%Basalt composite ceramic material.

[0033] Example 4: Mo ≤5 Si ≤3 C ≤1 Preparation of / 20wt.%Basalt composite ceramic materials This embodiment is basically the same as Embodiment 1, except that the amount of basalt powder added in step (1) is Mo. ≤ 5Si ≤3 C ≤1 20% of the ceramic matrix mass. All other conditions were the same as in Example 1, yielding Mo. ≤5 Si ≤3 C ≤1 / 20wt.%Basalt composite ceramic material.

[0034] Example 5: Mo ≤5 Si ≤3 C ≤1 Preparation of / 25wt.%Basalt composite ceramic materials This embodiment is basically the same as Embodiment 1, except that the amount of basalt powder added in step (1) is Mo. ≤ 5Si ≤3 C ≤1 25% of the ceramic matrix mass. The remaining conditions were the same as in Example 1, yielding Mo. ≤5 Si ≤3 C ≤1 / 25wt.%Basalt composite ceramic material.

[0035] Example 6: Mo ≤5 Si ≤3 C ≤1 Preparation of / 30wt.%Basalt composite ceramic materials This embodiment is basically the same as Embodiment 1, except that the amount of basalt powder added in step (1) is Mo. ≤ 5Si ≤3 C ≤1The ceramic matrix mass was 30%. All other conditions were the same as in Example 1, yielding Mo. ≤5 Si ≤3 C ≤1 / 30wt.%Basalt composite ceramic material.

[0036] The ceramic materials prepared in Examples 1-6 above were characterized structurally and their performance was evaluated. 1. Structural and morphological characterization Mo prepared in Example 1 ≤5 Si ≤3 C ≤1 X-ray diffraction analysis was performed on a 5wt.% Basalt composite ceramic material. For example... Figure 1 As shown, all diffraction peaks in the XRD pattern are related to Mo. 4.8 Si3C 0.6 The phase (PDF#73-1380) matches the standard card well, and no other impurity phases were detected, indicating that the in-situ reaction fully generated Mo. ≤5 Si ≤3 C ≤1 Ceramic matrix.

[0037] The sample from Example 1 was observed using a scanning electron microscope. For example... Figure 2 As shown, the material surface is dense with few defects such as pores and cracks, demonstrating a good sintering densification effect.

[0038] Energy dispersive spectroscopy (EDS) was performed on the sample from Example 1. For example... Figure 3 As shown, the elements are evenly distributed, and the basalt particles (rich in elements such as Si, Al, O, and Fe) are uniformly dispersed in Mo. ≤5 Si ≤3 C ≤1 in the matrix.

[0039] 2. Performance Evaluation (1) Mechanical properties The hardness of MoSiC-based basalt composite material (MoSiC) was determined using a Vickers microhardness tester. ≤5 Si ≤3 C ≤1The microhardness of the material was determined using the Basalt hardness test. Specific test parameters were as follows: test load was 500 gf, and the loading holding time was 10 s. To ensure data reliability, 10 defect-free random areas were selected for repeated testing of each sample, and the arithmetic mean of the 10 sets of valid data was used as the hardness characterization value of the sample. The material of this invention was processed into 20 mm × 4 mm × 2 mm sample strips, and the fracture toughness of the material was determined using the three-point bending method on a DY35 universal testing machine. The experimental span was 16 mm, and the loading speed was 0.05 mm / min. The room temperature hardness and fracture toughness data of the material of this invention and related materials are summarized in Table 1. This invention successfully prepared a composite material with both high hardness and high fracture toughness by introducing 5 wt% basalt particles into a MoSiC matrix. Experimental results showed that the Vickers hardness of this composite material reached 12.0 ± 0.2 GPa, and the fracture toughness was as high as 3.96 ± 0.12 MPa·m. 1 / 2 Compared to the matrix material without added basalt (1.3 MPa·m 1 / 2 The fracture toughness is improved by 67.2%, exhibiting excellent mechanical properties. Furthermore, the performance of this material is significantly superior to existing materials such as Mo5Si3, Mo5Si3B2, MoSi2, and multi-component silicides, especially in terms of fracture toughness.

[0040] Table 1 Mo ≤5 Si ≤3 C ≤1 Room temperature hardness and fracture toughness of Basalt materials and related materials

[0041] Note: [1] Suzuki Y, Niihara K. Synthesis and mechanical properties ofMo ≤5 Si3C ≤1 and Mo ≤5 Si3C ≤1 -based composites[J].Intermetallics, 1998, 6(1): 7-13. [2] Hayashi T, Ito K, Tanaka K. Physical and mechanical properties of single crystals of the Mo5Si3C phase[J]. Intermetallics, 2003, 11(8): 835-840. [3] Chu F, Thoma D J, McClellan K, et al. Synthesis and properties ofMo5Si3single crystals[J]. Intermetallics, 1999, 7(5): 611-620. [4] Ito K, Ihara K, Tanaka K, et al. Physical and mechanicalproperties ofsingle crystals of the T2 phase in the Mo–Si–B system[J].Intermetallics, 2001, 9(7): 591-602. [5] Vasudevan A K, Petrovic J J. A comparative overview ofmolybdenumdisilicide composites[J]. Materials Science and Engineering: A,1992, 155(1-2):1-17. [6] Li J, Chen S, Fan H, et al. High‐entropy(Ti 0.2 V 0.2 Nb 0.2 Mo 0.2 W 0.2 )Si2with excellent high‐temperature wearresistance[J]. Journal of the AmericanCeramic Society, 2024, 107(4):2750-2764. (2) Oxidation resistance The material of this invention was cut into blocks approximately 8 mm long, 4 mm wide, and 2 mm thick, and its surface was polished to a mirror finish. The oxidation experiment was conducted in a tube furnace in natural convection air, held at 1000 °C for 60 min, and then removed and cooled at a constant temperature in a vacuum drying oven, and the mass was recorded. Subsequently, the sample was placed back into the furnace for another 60 min of oxidation test, and then removed, weighed, and the morphology of the oxidized sample was photographed. A total of 3 cycles of oxidation test were conducted until the total oxidation time was increased to 180 min. The mass of the sample before and after the oxidation test was measured and recorded using an electronic balance with a sensitivity of ± 0.1 mg. To ensure the accuracy of the experiment, each sample was weighed at least 3 times. The oxidation resistance of the MoSiC-based basalt composite material was evaluated using formula (1): (1) In equation (1), ∆ w Weight gain per unit area due to oxidation (mg / cm²) 2 m0 is the initial mass of the sample before oxidation (mg); m1 is the final mass of the sample after oxidation (mg); A is the surface area of ​​the ceramic before oxidation (cm²). 2 ).

[0042] like Figure 4 As shown, this represents the Mo content at different basalt additions at 1000 °C. ≤5 Si ≤3 C ≤1 The oxidation weight gain curves of the Basalt composite ceramics, when fitted, show that the pure phase (0 wt.% Basalt) exhibits parabolic oxidation, while the oxidation kinetics of the composite ceramics change from parabolic to near-linear after the addition of basalt. Simultaneously, the addition of basalt significantly reduces mass loss, indicating that the components in the basalt (such as SiO2 and metal oxides) react at high temperatures to form a low-viscosity, flowable glassy oxide layer. This glassy phase can rapidly fill surface defects and cover the matrix surface, forming a continuous and dense protective layer that isolates the matrix from the oxidizing atmosphere. Therefore, the oxidation rate is "stable controlled," exhibiting a linear relationship of uniform mass loss over time, rather than the accelerated degradation of the pure phase material. The optimal oxidation resistance is observed at a Basalt addition level of 5 wt.%

[0043] The morphology of the samples also shows that from 60 min to 180 min, the surface of the pure phase sample (0 wt.% Basalt) gradually became rough and uneven, and even showed signs of peeling / pitting. However, the samples with 5 wt.% to 30 wt.% Basalt remained relatively smooth and dense even after the oxidation time was extended to 180 min, without obvious peeling or large-area corrosion. This confirms that the glassy oxide layer formed by basalt played a good protective role for the matrix, turning the oxidation process into a linear mode with a stable rate, and exhibiting excellent high-temperature oxidation resistance.

[0044] like Figure 5 As shown, this represents the Mo content at different basalt additions at 1000 °C. ≤5 Si ≤3 C ≤1 The graph shows the mass change of the Basalt composite ceramic sample after three cycles of oxidation. The results indicate that the pure phase material (0 wt.% Basalt) suffered the most severe mass loss during cyclic oxidation, with accelerated deterioration with increasing cycle count. After the introduction of basalt, the mass loss of all composite ceramics was significantly reduced, decreasing and stabilizing with increasing basalt content. The addition of basalt not only reduced the mass loss per cycle but also effectively suppressed the cumulative effect of oxidation, demonstrating its ability to rapidly form a protective glassy phase layer at high temperatures, significantly improving the material's resistance to cyclic oxidation. Specifically, Mo... ≤5 Si ≤3 C ≤1 / 5 wt.% Basalt composite ceramics exhibit the least mass loss and best high-temperature oxidation resistance after three oxidation cycles.

[0045] (3) High-temperature tribological properties The high-temperature tribological properties were tested using a high-temperature reciprocating friction and wear testing machine. The test temperature was 1000 ℃, Al2O3 balls were used as the friction pair, the load was 10 N, the reciprocating length was 5 mm, and the test time was 60 min.

[0046] like Figure 6 As shown, this is the prepared Mo. ≤5 Si ≤3 C ≤1 The average friction coefficient curve and wear rate of the / Basalt composite ceramic at 1000 ℃ are shown in the experimental results. ≤5 Si ≤3 C ≤1 / Basalt composite ceramics exhibit stable and excellent tribological properties at high temperatures, among which Mo ≤5 Si ≤3 C ≤1 / 5wt% Basalt composite ceramics exhibit the best tribological properties (0.516 and 3.3×10) at 1000 ℃. -5 mm 3 / (N·m)), relatively pure Mo ≤5 Si ≤3 C ≤1 Materials (0.556 and 3.3 × 10) -4 mm 3 The coefficient of friction decreased by 7.2% (N·m), and the wear rate decreased by an order of magnitude, indicating that Mo... ≤5 Si ≤3 C ≤1 / Basalt composite ceramics with relatively pure Mo ≤5 Si ≤3 C ≤1 The material exhibits superior tribological properties at high temperatures.

[0047] In summary, this invention synthesizes Mo by adding different mass fractions of basalt. ≤5 Si ≤3 C ≤1 / Basalt ceramics, compared to the pure phase (0 wt.% Basalt), the Mo of this invention ≤5 Si ≤3 C ≤1 Basalt ceramics possess excellent oxidation resistance and tribological properties at high temperatures, and are expected to serve as heat-resistant, wear-resistant, and other high-temperature thermal protection materials and high-temperature structural components, with great application potential in harsh working conditions and complex environments such as aviation, aerospace, and marine.

[0048] Although the present invention has been described in detail through the preferred embodiments above, it should be understood that the above description should not be considered as a limitation of the present invention. Various modifications and substitutions to the present invention will be apparent to those skilled in the art after reading the above description. Therefore, the scope of protection of the present invention should be defined by the appended claims.

Claims

1. A kind of Mo ≤5 Si ≤3 C ≤1 / Basalt composite ceramic material, characterized in that, The composite material is made of Mo ≤5 Si ≤3 C ≤1 The structure consists of a ceramic matrix and basalt particles uniformly dispersed within the matrix; the mass of the basalt particles is the Mo. ≤ 5Si ≤3 C ≤1 5% to 30% of the ceramic matrix mass.

2. The Mo according to claim 1 ≤5 Si ≤3 C ≤1 / Basalt composite ceramic material, characterized in that... The mass of the basalt particles is the Mo ≤5 Si ≤3 C ≤1 5% of the mass of the ceramic matrix.

3. The Mo according to claim 1 ≤5 Si ≤3 C ≤1 / Basalt composite ceramic material, characterized in that, The Mo ≤ 5Si ≤3 C ≤1 The ceramic matrix is ​​generated by in-situ reaction of Mo powder, Si powder and graphite powder during high-temperature sintering.

4. The Mo according to claim 1 ≤5 Si ≤3 C ≤1 / Basalt composite ceramic material, characterized in that, The basalt particles have a particle size of 1 μm to 100 μm and a purity of ≥99.9%; the Mo powder, Si powder and graphite powder have particle sizes of 1 μm to 50 μm and a purity of ≥99.9%.

5. A Mo as described in any one of claims 1 to 4 ≤5 Si ≤3 C ≤1 The method for preparing Basalt composite ceramic materials is characterized by... Includes the following steps: (1) Weigh out Mo powder, Si powder, and graphite powder according to the molar ratio of Mo, Si, and graphite of (3~5):(2~3):(0.5~1), and weigh out basalt powder, wherein the amount of basalt powder added is the amount of Mo... ≤5 Si ≤3 C ≤1 5% to 30% of the ceramic matrix mass; (2) The powder raw materials weighed in step (1) are mixed under an inert atmosphere and then ball-milled to disperse them evenly to obtain a mixed powder. (3) The mixed powder is pressed into a blank to obtain a green body; (4) The green body is sintered at high temperature under vacuum or inert atmosphere to allow Mo, Si and graphite to react in situ to generate Mo. ≤5 Si ≤3 C ≤1 Ceramic matrix, thereby obtaining Mo ≤5 Si ≤3 C ≤1 / Basalt composite ceramic material.

6. The preparation method according to claim 5, characterized in that, The ball milling in step (2) is a dry ball milling with a rotation speed of 200 r / min to 600 r / min and a milling time of 2 h to 12 h.

7. The preparation method according to claim 5, characterized in that, The pressing pressure in step (3) is 10 MPa to 100 MPa.

8. The preparation method according to claim 5, characterized in that, The high-temperature sintering temperature in step (4) is 1500 ℃~1700 ℃, and the sintering holding time is 10 min~60 min.

9. The preparation method according to claim 5, characterized in that, The high-temperature sintering described in step (4) employs spark plasma sintering, with a vacuum degree <10 during the sintering process. 1 Pa, heating rate of 10 ℃ / min~100 ℃ / min, and pressure gradually increased to 35 MPa while heating to sintering temperature.

10. The Mo according to any one of claims 1 to 4 ≤5 Si ≤3 C ≤1 Application of Basalt composite ceramic materials in the preparation of high-temperature structural components that are resistant to melting, wear, or oxidation.

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