Dense multi-component (Zr, Hf, Ta, Ti, Nb)N / amorphous Si3N4 composite ceramics and their preparation methods

Abstract

This invention relates to the field of ceramic materials technology, and discloses a dense multi-component (Zr,Hf,Ta,Ti,Nb)N / amorphous Si3N4 multiphase ceramic and its preparation method. A Zr source, Hf source, Ti source, Ta source, and Nb source are added to a Si-N source. After reaction, vacuum filtration is performed to obtain a Si-Zr-Hf-Ta-Ti-Nb-N precursor. The precursor is then pyrolyzed to obtain multi-component (Zr,Hf,Ta,Ti,Nb)N / amorphous Si3N4 multiphase ceramic powder. The multiphase ceramic powder is then sintered under high temperature and high pressure to obtain a dense multi-component (Zr,Hf,Ta,Ti,Nb)N / amorphous Si3N4 multiphase ceramic. The multiphase ceramic obtained by this invention exhibits a uniform elemental distribution, with the multi-component (Zr,Hf,Ta,Ti,Nb)N uniformly dispersed in the amorphous Si3N4 matrix, thus improving the mechanical properties of the multiphase ceramic.

Description

Technical Field

[0001] This invention relates to the field of ceramic materials technology, and in particular to dense multi-component (Zr,Hf,Ta,Ti,Nb)N / amorphous Si3N4 multiphase ceramics and their preparation methods. Background Technology

[0002] Amorphous Si3N4 ceramic materials possess advantages such as uniform structure, absence of grain boundary defects, and resistance to high-temperature oxidation. In use, they avoid the grain boundary brittleness and high-temperature softening problems common in crystalline ceramics, making them ideal high-temperature stable matrix materials. However, amorphous ceramics typically suffer from limited strength and poor toughness, necessitating the introduction of external reinforcing phases to improve both strength and toughness. Transition metal nitride high-entropy ceramics, as a new type of ceramic, are single-phase solid solution ceramics formed by four or more equimolar or near-equimolar cations (or anions) occupying the same sites in the crystal structure. (Zr,Hf,Ta,Ti,Nb)N is a nitride high-entropy ceramic material with high hardness, high melting point, and excellent wear resistance, applicable to aerospace, machining, and wear-resistant coatings. However, traditional high-entropy ceramic preparation processes often face problems such as uneven element distribution and coarse grains.

[0003] Furthermore, in the prior art, due to the use of powder metallurgy, which involves mixing powder particles with each other, multi-component (Zr, Hf, Ta, Ti, Nb)N particles cannot be uniformly dispersed in the amorphous Si3N4 matrix.

[0004] Therefore, there is an urgent need for dense multi-component (Zr,Hf,Ta,Ti,Nb)N / amorphous Si3N4 composite ceramics and their preparation methods to solve the above-mentioned technical problems. Summary of the Invention

[0005] The purpose of this invention is to address the problems of grain coarsening, product inhomogeneity, and weak grain boundary phases in traditional Si3N4-based multiphase ceramics. It provides a method for preparing dense multi-component (Zr,Hf,Ta,Ti,Nb)N / amorphous Si3N4 multiphase ceramics, achieving uniform dispersion of multi-component (Zr,Hf,Ta,Ti,Nb)N in the amorphous Si3N4 matrix and densification of the multiphase ceramic. Furthermore, through multiple enhancement effects such as interface strengthening, nano-dispersion strengthening, and crack propagation inhibition, the mechanical properties of the amorphous Si3N4 ceramic are improved.

[0006] To achieve the above objectives, the present invention is implemented according to the following technical solution: A method for preparing dense multi-component (Zr, Hf, Ta, Ti, Nb)N / amorphous Si3N4 composite ceramics includes the following steps: Zr, Hf, Ti, Ta, and Nb sources were added to a Si-N source. After reaction, vacuum filtration was performed to obtain a Si-Zr-Hf-Ta-Ti-Nb-N precursor. The Si-Zr-Hf-Ta-Ti-Nb-N precursor was then pyrolyzed to obtain a multi-component (Zr,Hf,Ta,Ti,Nb)N / amorphous Si3N4 multiphase ceramic powder. The multi-component (Zr,Hf,Ta,Ti,Nb)N / amorphous Si3N4 multiphase ceramic powder was then sintered under high temperature and high pressure to obtain a dense multi-component (Zr,Hf,Ta,Ti,Nb)N / amorphous Si3N4 multiphase ceramic.

[0007] Preferably, the Zr source is tetra(dimethylamino)zirconium, the Hf source is tetra(dimethylamino)hafnium, the Ti source is tetra(dimethylamino)titanium, the Ta source is tetra(dimethylamino)tantalum, the Nb source is tetra(dimethylamino)niobium, and the Si-N source is perhydropolysilazane.

[0008] Preferably, tetra(dimethylamino)zirconium, tetra(dimethylamino)hafnium, tetra(dimethylamino)titanium, tetra(dimethylamino)tantalum, and tetra(dimethylamino)niobium are added to the perhydropolysilazane by dropwise addition.

[0009] Preferably, the tetra(dimethylamino)zirconium is calculated as Zr, the tetra(dimethylamino)hafnium as Hf, the tetra(dimethylamino)titanium as Ti, the tetra(dimethylamino)tantalum as Ta, the tetra(dimethylamino)niobium as Nb, and the perhydropolysilazane as Si, and the molar ratio of tetra(dimethylamino)zirconium, tetra(dimethylamino)hafnium, tetra(dimethylamino)titanium, tetra(dimethylamino)tantalum, tetra(dimethylamino)niobium, and perhydropolysilazane is Zr:Hf:Ti:Ta:Nb:Si=1:1:1:1:1:3.

[0010] Preferred preparation process of Si-Zr-Hf-Ta-Ti-Nb-N precursor: Under the protection of a double-row circulating argon atmosphere, tetra(dimethylamino)zirconium, tetra(dimethylamino)hafnium, tetra(dimethylamino)titanium, tetra(dimethylamino)tantalum, and tetra(dimethylamino)niobium were sequentially added dropwise to a Schlenk reaction flask containing perhydropolysilazane. The mixture was magnetically stirred for 2 hours under flowing argon atmosphere to obtain a mixed solution. The mixed solution was then filtered under vacuum to remove the reaction solvent, yielding the Si-Zr-Hf-Ta-Ti-Nb-N precursor.

[0011] Preferably, the vacuum filtration process is as follows: Protected by a liquid nitrogen cold trap, at a vacuum of 60 °C (vacuum degree of 10). -6 Filter under vacuum for 3 hours under the condition of Pa) to remove the reaction solvent, and then slowly restore to room temperature to obtain the Si-Zr-Hf-Ta-Ti-Nb-N precursor.

[0012] The precursor synthesis of this invention uses the polymer molecule perhydropolysilazane as the Si-N source, tetra(dimethylamino)zirconium as the Zr source, tetra(dimethylamino)hafnium as the Hf source, tetra(dimethylamino)titanium as the Ti source, tetra(dimethylamino)tantalum as the Ta source, and tetra(dimethylamino)niobium as the Nb source. It is carried out under Ar protection in a double-row tube and Schlenk reaction flask to avoid contamination caused by the sensitivity of organic molecules to water and oxygen.

[0013] Preferably, the pyrolysis temperature is 1100-1400 ℃.

[0014] Preferably, the pyrolysis time is 2 hours.

[0015] A further preferred pyrolysis temperature is 1300℃.

[0016] Preferably, the pyrolysis is carried out in a nitrogen atmosphere, an ammonia atmosphere, or a mixed atmosphere of nitrogen and ammonia.

[0017] Preferably, during the high-temperature and high-pressure sintering process, the sintering temperature is 1000-1400℃, the sintering pressure is 5GPa, and the sintering temperature is held for 30 minutes.

[0018] A further preferred sintering temperature is 1000℃.

[0019] Specifically, it includes the following steps: Tetra(dimethylamino)zirconium, tetra(dimethylamino)hafnium, tetra(dimethylamino)titanium, tetra(dimethylamino)tantalum, and tetra(dimethylamino)niobium were sequentially added dropwise to a perhydropolysilazane. After thorough mixing, the mixture was vacuum filtered to obtain a Si-Zr-Hf-Ta-Ti-Nb-N precursor. The Si-Zr-Hf-Ta-Ti-Nb-N precursor was then pyrolyzed under specific temperature and atmosphere to obtain a multi-component (Zr,Hf,Ta,Ti,Nb)N / amorphous Si3N4 multiphase ceramic powder. This multi-component (Zr,Hf,Ta,Ti,Nb)N / amorphous Si3N4 multiphase ceramic powder was then sintered under high temperature and pressure to obtain a dense multi-component (Zr,Hf,Ta,Ti,Nb)N / amorphous Si3N4 multiphase ceramic.

[0020] The present invention also includes dense multi-component (Zr,Hf,Ta,Ti,Nb)N / amorphous Si3N4 multiphase ceramics prepared by the preparation method described above.

[0021] The dense multi-component (Zr, Hf, Ta, Ti, Nb)N / amorphous Si3N4 multiphase ceramic of the present invention is a multiphase ceramic with uniform distribution of Si, Zr, Hf, Ta, Ti, Nb and N elements at the molecular scale and a multi-component / amorphous structure, which has broad prospects for engineering applications.

[0022] This invention uses perhydropolysilazane, tetra(dimethylamino)zirconium, tetra(dimethylamino)hafnium, tetra(dimethylamino)titanium, tetra(dimethylamino)tantalum, and tetra(dimethylamino)niobium as raw materials to design and synthesize Si-Zr-Hf-Ta-Ti-Nb-N polymer precursors at the molecular level through polymer-derived ceramic technology. Subsequently, by controlling the pyrolysis of this amorphous ceramic under different temperatures and atmospheres, a mixed powder with uniformly dispersed (Zr, Hf, Ta, Ti, Nb)N particles in an amorphous Si3N4 matrix is ​​obtained. The resulting composite ceramic powder is then sintered under high temperature and high pressure to prepare a dense multi-component / amorphous ceramic. This invention ensures the uniform and controllable composition of the cationic components in (Zr,Hf,Ta,Ti,Nb)N high-entropy ceramics through molecular design, effectively avoiding problems such as uneven mixing or incomplete reaction that easily occur in traditional solid-phase mixing methods. Simultaneously, the nano-reinforcing phase (Zr,Hf,Ta,Ti,Nb)N is uniformly distributed within amorphous Si3N4. The employed pyrolysis path and conditions ensure the formation of amorphous Si3N4. The composite ceramic is sintered using a high-temperature, high-pressure process, achieving both densification of the multi-component ceramic and successful preservation of the multi-component and amorphous structure. The resulting multi-component ceramic exhibits improved mechanical properties and thermal stability.

[0023] Mechanism of action: Traditional high-entropy ceramic preparation processes often face problems such as uneven element distribution and coarse grains. Furthermore, the preparation of amorphous Si3N4 ceramic materials using traditional methods presents challenges in high-temperature crystallization. Therefore, developing a novel preparation technique that enables controllable ceramic components and tunable scale at the atomic level is of great significance for promoting the development of structural ceramic materials. The multi-component (Zr, Hf, Ta, Ti, Nb)N / amorphous Si3N4 multiphase ceramic of this invention represents an important direction for the development of advanced structural ceramics due to its excellent hardness and thermal stability.

[0024] Polymer-derived ceramics (PDCs) offer a novel technological approach to addressing the aforementioned challenges. By designing the composition of precursors containing Si-Zr-Hf-Ta-Ti-Nb-N bonds at the molecular level, Si, Zr, Hf, Ta, Ti, Nb, and N elements can be uniformly distributed within the precursor network. Controlled pyrolysis in ammonia, nitrogen, or a mixture thereof enables the gradual removal of carbon sources, reconstruction of metal-nitrogen bonds, and local phase separation, thereby generating a multi-component (Zr, Hf, Ta, Ti, Nb) N phase and simultaneously obtaining an amorphous Si3N4 matrix, constructing a nanoscale multiphase structure with clear interfaces and controllable scale. Compared to traditional methods, this route offers advantages such as lower reaction temperature, higher compositional uniformity, and more flexible structural control.

[0025] In this system, the amorphous precursors of Zr-Hf-Ta-Ti-Nb-N bonds and Si-N bonds, due to their high reactivity, become key intermediates for constructing multi-component (Zr,Hf,Ta,Ti,Nb)N / amorphous Si3N4 composite ceramics. By controlling the degree of crosslinking and the atmosphere composition, the nucleation and growth behavior of multi-component (Zr,Hf,Ta,Ti,Nb)N grains can be precisely regulated, while stabilizing the formation of amorphous Si3N4, enabling the composite ceramics to achieve uniform phase separation at the nanoscale.

[0026] Simultaneously, high-temperature and high-pressure sintering technology was employed to achieve densification of multi-component (Zr,Hf,Ta,Ti,Nb)N / amorphous Si3N4 multiphase ceramics under the coupled effect of isostatic pressure and temperature. The introduction of high pressure effectively lowered the sintering temperature, preventing grain growth of (Zr,Hf,Ta,Ti,Nb)N particles and crystallization of amorphous Si3N4, effectively preserving the crystal structure designed using polymer precursor technology. This successfully prepared multi-component (Zr,Hf,Ta,Ti,Nb)N / amorphous Si3N4 multiphase ceramics. This provides competitive technical support for the engineering preparation of novel high-performance nano-multiphase ceramic systems, possessing significant theoretical research value and broad application prospects.

[0027] This invention achieves a multi-scale synergistic enhancement effect by co-dissolving five refractory transition metals (Zr, Hf, Ta, Ti, Nb) to form high-entropy nitride nanocrystals and then compositing them with an amorphous Si3N4 matrix. On one hand, the differences in atomic size and bond energy among the five elements induce lattice distortion and retarded diffusion effects, resulting in strong solid solution strengthening within the nanocrystals and significantly inhibiting high-temperature grain coarsening. Simultaneously, a "cocktail" effect harmonizes the contradictions between hardness, toughness, and oxidation resistance. On the other hand, the amorphous Si3N4 matrix not only physically confines and pins the nanocrystals at the interface, effectively constraining grain growth and viscous flow at high temperatures, but also enhances the bonding strength at the interface through chemical bonding. Furthermore, it synergistically constructs a multilayered, dense oxide film composed of complex oxides and SiO2 with the high-entropy nitrides during oxidation. This results in multiphase ceramics exhibiting comprehensive advantages surpassing traditional single-phase materials in key properties such as ultra-high hardness, high-temperature creep resistance, thermal stability, and resistance to oxidation and ablation.

[0028] Beneficial Effects: This invention utilizes polymer-derived ceramic technology to regulate the molecular-level structure of Si-Zr-Hf-Ta-Ti-Nb-N, promoting the formation of an amorphous Si-Zr-Hf-Ta-Ti-Nb-N network. By controlling the pyrolysis atmosphere and temperature, nano-(Zr,Hf,Ta,Ti,Nb)N ceramics are prepared, avoiding the crystallization of the amorphous Si3N4 matrix. The high-temperature, high-pressure sintering process preserves the size and structural characteristics of both the multi-component (Zr,Hf,Ta,Ti,Nb)N and amorphous Si3N4, while successfully achieving densification of the multiphase ceramic. The resulting multiphase ceramic exhibits uniform elemental distribution, with the multi-component (Zr,Hf,Ta,Ti,Nb)N uniformly dispersed within the amorphous Si3N4 matrix, thus enhancing the mechanical properties of the multiphase ceramic.

[0029] Nano-high entropy (Zr,Hf,Ta,Ti,Nb)N, as a multi-component high entropy ceramic, possesses advantages such as high hardness and good wear resistance. Introducing it as a reinforcing phase into an amorphous Si3N4 matrix can achieve a synergistic improvement in the strength, toughness, and wear resistance of amorphous Si3N4 ceramics.

[0030] This invention proposes a method for preparing multi-component (Zr, Hf, Ta, Ti, Nb)N / amorphous Si3N4 multiphase ceramics, overcoming the difficulties in preparing multi-component / amorphous ceramics and successfully preparing such ceramics. This demonstrates the significant importance of this technology for the development of amorphous / multi-component structure ceramics and thermal protection components, showcasing outstanding scientific research value and broad engineering application prospects. Attached Figure Description

[0031] Figure 1 The hardness test results of dense multi-component (Zr,Hf,Ta,Ti,Nb)N / amorphous Si3N4 multiphase ceramics obtained at different sintering temperatures in Examples 1, 4 and 7 of this invention are shown. Figure 2 TEM image of the multi-component (Zr,Hf,Ta,Ti,Nb)N / amorphous Si3N4 multiphase ceramic prepared in Example 2 of the present invention; Figure 3 The XRD patterns are of the multi-component (Zr, Hf, Ta, Ti, Nb)N / amorphous Si3N4 composite ceramics prepared in Examples 2 and 6 of this invention. Detailed Implementation

[0032] The present invention will be further described below with reference to specific embodiments. The illustrative embodiments and descriptions herein are used to explain the present invention, but are not intended to limit the present invention.

[0033] There are no particular restrictions on the source of any raw materials used in this invention; they can be purchased from the market or prepared using conventional methods known to those skilled in the art.

[0034] There are no particular restrictions on the purity of any of the raw materials used in this invention; however, it is preferred to use materials with conventional purity levels used in the field.

[0035] All processes in this invention are referred to by common abbreviations in the field. Each abbreviation is clear and specific in its relevant application, and those skilled in the art can understand the conventional process based on the abbreviation.

[0036] Example 1 A method for preparing multi-component (Zr, Hf, Ta, Ti, Nb)N / amorphous Si3N4 multiphase ceramics includes the following steps: Tetra(dimethylamino)zirconium, tetra(dimethylamino)hafnium, tetra(dimethylamino)titanium, tetra(dimethylamino)tantalum, and tetra(dimethylamino)niobium were sequentially added dropwise to a Schlenk flask containing perhydropolysilazane. The mixture was magnetically stirred for 2 hours under flowing argon atmosphere to obtain a mixed solution. Then, under the protection of a liquid nitrogen cold trap, the mixture was subjected to a vacuum of 60 °C (vacuum degree 10). -6 (Pa) Filter for 3 hours to remove the reaction solvent, then slowly restore to room temperature to obtain the Si-Zr-Hf-Ta-Ti-Nb-N precursor. The tetra(dimethylamino)zirconium is calculated as Zr, tetra(dimethylamino)hafnium as Hf, tetra(dimethylamino)titanium as Ti, tetra(dimethylamino)tantalum as Ta, tetra(dimethylamino)niobium as Nb, and perhydropolysilazane as Si. The molar ratio of tetra(dimethylamino)zirconium, tetra(dimethylamino)hafnium, tetra(dimethylamino)titanium, tetra(dimethylamino)tantalum, tetra(dimethylamino)niobium, and perhydropolysilazane is Zr:Hf:Ti:Ta:Nb:Si = 1:1:1:1:1:3.

[0037] Subsequently, under an ammonia atmosphere, the obtained Si-Zr-Hf-Ta-Ti-Nb-N precursor was heated to its pyrolysis temperature of 1100 °C at a heating rate of 2 °C / min and held for 2 hours to obtain a multi-component (Zr,Hf,Ta,Ti,Nb)N / amorphous Si3N4 multiphase ceramic powder. The obtained multiphase ceramic powder was placed into a pyrophyllite mold and held at 5 GPa and 1000 °C for 30 minutes. The final multi-component (Zr,Hf,Ta,Ti,Nb)N / amorphous Si3N4 multiphase ceramic was obtained. Its hardness test results are as follows... Figure 1 As shown.

[0038] Example 2 The difference between this embodiment and Embodiment 1 is that the pyrolysis temperature is 1200℃, while the remaining steps are the same as in Embodiment 1.

[0039] Example 3 The difference between this embodiment and Embodiment 1 is that the pyrolysis temperature is 1400℃, while the remaining steps are the same as in Embodiment 1.

[0040] Example 4 The preparation process of multi-component (Zr, Hf, Ta, Ti, Nb)N / amorphous Si3N4 multiphase ceramics includes the following steps: Tetra(dimethylamino)zirconium, tetra(dimethylamino)hafnium, tetra(dimethylamino)titanium, tetra(dimethylamino)tantalum, and tetra(dimethylamino)niobium were sequentially added dropwise to a Schlenk flask containing perhydropolysilazane. The mixture was magnetically stirred for 2 hours under flowing argon atmosphere to obtain a mixed solution. Then, under the protection of a liquid nitrogen cold trap, the mixture was subjected to a vacuum of 60 °C (vacuum degree 10). -6 (Pa) Filter for 3 hours to remove the reaction solvent, then slowly restore to room temperature to obtain the Si-Zr-Hf-Ta-Ti-Nb-N precursor. The tetra(dimethylamino)zirconium is calculated as Zr, tetra(dimethylamino)hafnium as Hf, tetra(dimethylamino)titanium as Ti, tetra(dimethylamino)tantalum as Ta, tetra(dimethylamino)niobium as Nb, and perhydropolysilazane as Si. The molar ratio of tetra(dimethylamino)zirconium, tetra(dimethylamino)hafnium, tetra(dimethylamino)titanium, tetra(dimethylamino)tantalum, tetra(dimethylamino)niobium, and perhydropolysilazane is Zr:Hf:Ti:Ta:Nb:Si = 1:1:1:1:1:3.

[0041] Subsequently, under an ammonia atmosphere, the obtained Si-Zr-Hf-Ta-Ti-Nb-N precursor was heated to its pyrolysis temperature of 1100 °C at a heating rate of 2 °C / min and held for 2 hours to obtain a multi-component (Zr,Hf,Ta,Ti,Nb)N / amorphous Si3N4 multiphase ceramic powder. The obtained multiphase ceramic powder was placed into a pyrophyllite mold and held at 5 GPa and 1200 °C for 30 minutes. The final multi-component (Zr,Hf,Ta,Ti,Nb)N / amorphous Si3N4 multiphase ceramic was obtained. Its hardness test results are as follows... Figure 1 As shown.

[0042] Example 5 The difference between this embodiment and embodiment 4 is that the pyrolysis temperature is 1200 ℃, while the other steps are the same as in embodiment 4.

[0043] Example 6 The difference between this embodiment and embodiment 4 is that the pyrolysis temperature is 1300 ℃, while the other steps are the same as in embodiment 4.

[0044] Example 7 The preparation process of multi-component (Zr, Hf, Ta, Ti, Nb)N / amorphous Si3N4 multiphase ceramics includes the following steps: Tetra(dimethylamino)zirconium, tetra(dimethylamino)hafnium, tetra(dimethylamino)titanium, tetra(dimethylamino)tantalum, and tetra(dimethylamino)niobium were sequentially added dropwise to a Schlenk flask containing perhydropolysilazane. The mixture was magnetically stirred for 2 hours under flowing argon atmosphere to obtain a mixed solution. Then, under the protection of a liquid nitrogen cold trap, the mixture was subjected to a vacuum of 60 °C (vacuum degree 10). -6 (Pa) Filter for 3 hours to remove the reaction solvent, then slowly restore to room temperature to obtain the Si-Zr-Hf-Ta-Ti-Nb-N precursor. The tetra(dimethylamino)zirconium is calculated as Zr, tetra(dimethylamino)hafnium as Hf, tetra(dimethylamino)titanium as Ti, tetra(dimethylamino)tantalum as Ta, tetra(dimethylamino)niobium as Nb, and perhydropolysilazane as Si. The molar ratio of tetra(dimethylamino)zirconium, tetra(dimethylamino)hafnium, tetra(dimethylamino)titanium, tetra(dimethylamino)tantalum, tetra(dimethylamino)niobium, and perhydropolysilazane is Zr:Hf:Ti:Ta:Nb:Si = 1:1:1:1:1:3.

[0045] Subsequently, under a mixed atmosphere of ammonia and nitrogen (70% ammonia + 30% nitrogen), the obtained Si-Zr-Hf-Ta-Ti-Nb-N precursor was heated to its pyrolysis temperature of 1100 °C at a heating rate of 2 °C / min and held for 2 hours to obtain multi-component (Zr,Hf,Ta,Ti,Nb)N / amorphous Si3N4 multiphase ceramic powder. The obtained multiphase ceramic powder was placed into a pyrophyllite mold and held at 5 GPa and 1400 °C for 30 minutes. The final multi-component (Zr,Hf,Ta,Ti,Nb)N / amorphous Si3N4 multiphase ceramic was obtained. Its hardness test results are as follows... Figure 1 As shown.

[0046] Example 8 The difference between this embodiment and embodiment 7 is that the pyrolysis temperature is 1200 ℃, while the other steps are the same as in embodiment 7.

[0047] Example 9 The difference between this embodiment and embodiment 7 is that the pyrolysis temperature is 1300 ℃, while the other steps are the same as in embodiment 7.

[0048] like Figure 1The figure shows the hardness test results of multi-component (Zr,Hf,Ta,Ti,Nb)N / amorphous Si3N4 multiphase ceramics obtained in Examples 1, 4, and 7 at different sintering temperatures. The temperatures in the figure refer to the temperatures during high-temperature and high-pressure sintering in a pyrophyllite mold. "1000℃" represents Example 1, "1200℃" represents Example 4, and "1400℃" represents Example 7. Compared with traditional Si3N4 ceramic materials, multi-component (Zr,Hf,Ta,Ti,Nb)N / amorphous Si3N4 multiphase ceramics have higher hardness, which is attributed to the reinforcing effect of the introduced multi-component (Zr,Hf,Ta,Ti,Nb)N.

[0049] like Figure 2 The image shown is a TEM image of the multi-component (Zr,Hf,Ta,Ti,Nb)N / amorphous Si3N4 composite ceramic prepared in Example 2 of the present invention. like Figure 3 The figure shows the XRD patterns of the multi-component (Zr,Hf,Ta,Ti,Nb)N / amorphous Si3N4 multiphase ceramics prepared in Examples 2 and 6 of this invention. The temperatures in the figure refer to the pyrolysis temperatures. "1200℃" in the figure represents Example 2, and "1300℃" in the figure represents Example 6.

[0050] In summary, the multi-component (Zr, Hf, Ta, Ti, Nb)N / amorphous Si3N4 multiphase ceramic preparation method proposed in this invention significantly improves the hardness of multiphase ceramics, providing an important theoretical basis and technical support for the development and application of nitride ceramic materials.

[0051] The technical solutions of the present invention are not limited to the specific embodiments described above. Any technical modifications made in accordance with the technical solutions of the present invention fall within the protection scope of the present invention.

Claims

1. A method for preparing dense multi-component (Zr, Hf, Ta, Ti, Nb)N / amorphous Si3N4 multiphase ceramics, characterized in that, Includes the following steps: Zr, Hf, Ti, Ta, and Nb sources were added to a Si-N source. After reaction, vacuum filtration was performed to obtain a Si-Zr-Hf-Ta-Ti-Nb-N precursor. The Si-Zr-Hf-Ta-Ti-Nb-N precursor was then pyrolyzed to obtain a multi-component (Zr,Hf,Ta,Ti,Nb)N / amorphous Si3N4 multiphase ceramic powder. The multi-component (Zr,Hf,Ta,Ti,Nb)N / amorphous Si3N4 multiphase ceramic powder was then sintered under high temperature and high pressure to obtain a dense multi-component (Zr,Hf,Ta,Ti,Nb)N / amorphous Si3N4 multiphase ceramic.

2. The method for preparing dense multi-component (Zr, Hf, Ta, Ti, Nb)N / amorphous Si3N4 multiphase ceramic according to claim 1, characterized in that: The Zr source is tetra(dimethylamino)zirconium, the Hf source is tetra(dimethylamino)hafnium, the Ti source is tetra(dimethylamino)titanium, the Ta source is tetra(dimethylamino)tantalum, the Nb source is tetra(dimethylamino)niobium, and the Si-N source is perhydropolysilazane.

3. The method for preparing dense multi-component (Zr, Hf, Ta, Ti, Nb)N / amorphous Si3N4 multiphase ceramic according to claim 2, characterized in that: Tetra(dimethylamino)zirconium, tetra(dimethylamino)hafnium, tetra(dimethylamino)titanium, tetra(dimethylamino)tantalum, and tetra(dimethylamino)niobium are added dropwise to perhydropolysilazane.

4. The method for preparing dense multi-component (Zr, Hf, Ta, Ti, Nb)N / amorphous Si3N4 multiphase ceramic according to claim 2, characterized in that: The molar ratio of tetra(dimethylamino)zirconium (calculated as Zr), tetra(dimethylamino)hafnium (calculated as Hf), tetra(dimethylamino)titanium (calculated as Ti), tetra(dimethylamino)tantalum (calculated as Ta), tetra(dimethylamino)niobium (calculated as Nb), and perhydropolysilazane (calculated as Si) is Zr:Hf:Ti:Ta:Nb:Si = 1:1:1:1:1:

3.

5. The method for preparing dense multi-component (Zr, Hf, Ta, Ti, Nb)N / amorphous Si3N4 multiphase ceramic according to claim 1, characterized in that: The pyrolysis temperature is 1100-1400 ℃.

6. The method for preparing dense multi-component (Zr, Hf, Ta, Ti, Nb)N / amorphous Si3N4 multiphase ceramic according to claim 1, characterized in that: The pyrolysis time was 2 hours.

7. The method for preparing dense multi-component (Zr, Hf, Ta, Ti, Nb)N / amorphous Si3N4 multiphase ceramic according to claim 5, characterized in that: The pyrolysis temperature is 1300℃.

8. The method for preparing dense multi-component (Zr, Hf, Ta, Ti, Nb)N / amorphous Si3N4 multiphase ceramic according to claim 1, characterized in that: The pyrolysis is carried out in a nitrogen atmosphere, an ammonia atmosphere, or a mixed atmosphere of nitrogen and ammonia.

9. The method for preparing dense multi-component (Zr, Hf, Ta, Ti, Nb)N / amorphous Si3N4 multiphase ceramic according to claim 1, characterized in that: During the high-temperature and high-pressure sintering process, the sintering temperature is 1000-1400℃, the sintering pressure is 5GPa, and the sintering temperature is held for 30 minutes.

10. A dense multi-component (Zr,Hf,Ta,Ti,Nb)N / amorphous Si3N4 multiphase ceramic prepared by the preparation method according to any one of claims 1-9.

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