CN112266251B - A method for preparing silicon nitride/titanium carbide ceramic materials based on spark plasma sintering - Google Patents

Abstract

The invention specifically relates to a method for preparing silicon nitride/titanium carbide ceramic materials based on discharge plasma sintering. Silicon nitride-based ceramic materials have good mechanical properties and stability, and the preparation of high-performance Si ₃ N ₄ /SiC ceramic materials is expected to be widely used in the industrial field. The invention provides a method for preparing Si ₃ N ₄ /TiC ceramic materials based on discharge plasma sintering, using α-Si ₃ N ₄ as the matrix, TiC as the reinforcing phase, and Al ₂ O ₃ and Y ₂ O ₃ as sintering aids. , after wet ball milling, drying and discharge plasma sintering, the sintering temperature is 1650-1750℃ and the holding time is 20-35min. The Si ₃ N ₄ /TiC ceramic material prepared by the invention has good sintering density, and the flexural strength, fracture toughness and hardness of the ceramic material are not less than 700MPa, 6.1MPa·m ^1/2 and 13GPa.

Description

Preparation of silicon nitride/titanium carbide ceramic material based on spark plasma sintering method

Technical field

The invention belongs to the technical field of ceramic material preparation, and specifically relates to a silicon nitride/titanium carbide (Si ₃ N ₄ /TiC) ceramic material preparation method based on discharge plasma sintering, and the Si ₃ N ₄ /TiC ceramic material prepared by the method. and applications.

Background technique

The information in this Background section is disclosed solely for the purpose of increasing understanding of the general background of the invention and is not necessarily considered to be an admission or in any way implying that the information constitutes prior art that is already known to a person of ordinary skill in the art.

As the most popular ultrafast sintering technology at present, spark plasma sintering (SPS) is mostly used to prepare nanostructured materials, amorphous materials, intermetallic compounds, metal matrix and ceramic matrix composite materials. Compared with traditional sintering methods, spark plasma sintering (SPS) technology has a faster heating speed and can achieve the same sintering effect in a shorter sintering time. The rapid heating of materials prepared by spark plasma sintering (SPS) is due to the skin effect of the DC component and AC component in the pulse current and the small heat capacity of the heating system. During sintering, most of the heat is generated from the inner edge of the mold. The higher the temperature, the higher the temperature of the powder surface. In spark plasma sintering (SPS), the powder is placed in a graphite mold, and while pressure is applied to the powder, an electric current is passed through the mold and the sample (if the latter is a conductive material) to heat the powder body, if the powder is a non-conductive material , the current mainly flows through the mold to generate heat. In addition to the lower sintering temperature and short sintering time that can successfully prepare nanomaterials without obvious grain growth, the SPS process has the following advantages when preparing ceramic materials due to its unique heating system: it can clean grain boundaries, It can significantly increase superplasticity, reduce grain boundary segregation, enhance bonding quality, improve thermoelectric properties and improve the ductility of alloy ceramics.

Silicon nitride-based ceramic materials have high fracture toughness and strength and excellent thermal shock resistance, corrosion resistance and wear resistance, and are widely used in industrial fields. Therefore, many researchers have focused on how to use appropriate sintering methods to prepare high-performance Si ₃ N _4- based ceramic materials. Currently, the commonly used sintering methods for sintered silicon nitride ceramic materials include the following: pressureless sintering, reaction sintering, gas pressure sintering (GPS), hot isostatic pressing (HIP) and hot press (HP) sintering. Chinese patent CN109516814 A discloses a Si ₃ N ₄ /SiC composite phase ceramic material and a preparation method thereof. The Si ₃ N ₄ /SiC composite phase ceramic material uses Si ₃ N ₄ and SiC as raw material powders, with Tm ₂ O ₃ and MgO are used as sintering aids and are prepared by hot pressing sintering. Although this method obtains high-density Si ₃ N ₄ /SiC ceramic materials, its sintering time is long.

Contents of the invention

In view of the above research background, the inventor believes that providing a preparation method with higher sintering efficiency will help improve the productivity of Si ₃ N ₄ /SiC ceramic materials. Spark plasma sintering is a sintering process with the characteristics of pulse The plasma generated by the current and the pressure during the sintering process are beneficial to reducing the sintering temperature of the powder. At the same time, the characteristics of low voltage and high current can make the powder sintering and dense quickly. The present invention applies it to the sintering of Si ₃ N ₄ /SiC ceramic materials, and successfully shortens the sintering time to half of the pressure sintering time. In addition, the prepared Si ₃ N ₄ /SiC ceramic materials are sintered using the method provided by the present invention. It also has excellent mechanical properties.

Based on the above technical effects, the present invention provides the following technical solutions:

A first aspect of the present invention provides a method for preparing Si ₃ N ₄ /TiC ceramic materials based on spark plasma sintering. The preparation method includes: using Si ₃ N ₄ as a matrix, TiC as a reinforcing phase, Al ₂ O ₃ and Y ₂ O ₃ is a sintering aid, which is prepared by wet ball milling and discharge plasma sintering of the above raw materials.

After using discharge plasma sintering, the preparation time of the Si ₃ N ₄ /TiC ceramic material is significantly shortened. The present invention proposes a corresponding temperature rise sintering program for discharge plasma sintering. According to the test results, based on the sintering method provided by the present invention, It can inhibit the excessive growth of β-Si ₃ N ₄ and increase the proportion of α crystal phase in the sintered product. Since the α-Si ₃ N ₄ crystal phase has higher strength, the ceramic material prepared by the method of the present invention is more suitable for cutting. Preparation of tools, especially for ceramic knives. And the introduction of TiC can better improve the electrical conductivity and EDM performance of Si ₃ N ₄ .

The beneficial effects of one or more of the above technical solutions are:

The preparation process of the present invention is simple, the sintering time is short, and the sintering of the Si ₃ N ₄ /TiC ceramic material can be completed in a relatively short period of time. Compared with hot press sintering, the time used by spark plasma sintering is only 1/2 of that of hot press sintering. Moreover, the Si ₃ N ₄ /TiC ceramic material prepared by the present invention has excellent mechanical properties, flexural strength, fracture toughness, and Vickers hardness. At the same time, due to the unique sintering mechanism of SPS, the growth of β-Si ₃ N ₄ is inhibited and avoids The larger β-Si ₃ N ₄ is obtained, which is beneficial to the performance of Si ₃ N ₄ /TiC ceramic materials.

Description of drawings

The description and drawings that constitute a part of the present invention are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention.

Figure 1 is a graph showing the sintering temperature and the displacement of the upper indenter during spark plasma sintering of the Si ₃ N ₄ /TiC ceramic material prepared in Example 1;

Figure 2 is an XRD detection chart of the Si ₃ N ₄ /TiC ceramic material prepared in Example 1;

Figure 3 is an SEM image of the fracture surface of the Si ₃ N ₄ /TiC ceramic material prepared in Example 1.

Detailed ways

It should be noted that the following detailed description is illustrative and is intended to provide further explanation of the present invention. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

It should be noted that the terms used herein are for the purpose of describing specific embodiments only, and are not intended to limit the exemplary embodiments according to the present invention. As used herein, the singular forms are also intended to include the plural forms unless the context clearly indicates otherwise. Furthermore, it will be understood that when the terms "comprises" and/or "includes" are used in this specification, they indicate There are features, steps, operations, means, components and/or combinations thereof.

As introduced in the background art, the existing technical problems of high-density Si ₃ N ₄ /SiC ceramic materials are long sintering time and low production efficiency. In order to solve the above technical problems, the present invention proposes a preparation method of Si ₃ N ₄ /TiC ceramic materials based on discharge plasma sintering. This preparation method shortens the time of 1/2 compared with the existing hot press sintering, and the preparation method The Si ₃ N ₄ /TiC ceramic prepared by this method has good mechanical properties.

A first aspect of the present invention provides a method for preparing Si ₃ N ₄ /TiC ceramic materials based on spark plasma sintering. The preparation method includes: using Si ₃ N ₄ as a matrix, TiC as a reinforcing phase, Al ₂ O ₃ and Y ₂ O ₃ is a sintering aid, which is prepared by wet ball milling and discharge plasma sintering of the above raw materials.

Preferably, in the preparation method, the volume percentage of the raw materials is as follows: α-Si ₃ N ₄ 70-85%, TiC 5-15%, Al ₂ O ₃ 1-6%, Y ₂ O ₃ 3-7 %.

Further, the volume percentage of TiC is 7-10%, or the volume percentage of Al ₂ O ₃ is 2-4%, or the volume percentage of Y ₂ O ₃ is 4-6%, and the above raw materials are Adjust within the stated volume percentage range, and the sum of the remaining components is 100%.

In some specific implementations of the above preferred technical solution, the volume percentage of the raw materials is as follows: α-Si ₃ N ₄ 80%, TiC 10%, Al ₂ O ₃ 4%, Y ₂ O ₃ 6%.

In some specific implementations of the above preferred technical solution, the volume percentage of the raw materials is as follows: α-Si ₃ N ₄ 82%, TiC 10%, Al ₂ O ₃ 3%, Y ₂ O ₃ 5%.

In some specific implementations of the above preferred technical solution, the volume percentage of the raw materials is as follows: α-Si ₃ N ₄ 75%, TiC 15%, Al ₂ O ₃ 4%, Y ₂ O ₃ 6%.

Preferably, the average particle size of the α-Si ₃ N ₄ powder is 0.5-1 μm.

Preferably, the average particle size of the TiC powder is 0.5-1 μm.

Preferably, the average particle size of the Al ₂ O ₃ powder is 0.5-2 μm.

Preferably, the average particle size of the Y ₂ O ₃ powder is 0.1-0.5 μm.

Preferably, the preparation method specifically includes the following steps:

(1) Add α-Si ₃ N ₄ and TiC powder to the dispersion medium respectively to disperse them evenly to obtain α-Si ₃ N ₄ suspension and TiC suspension, and mix them to obtain a multi-phase suspension;

(2) Weigh 1-5wt% of the dispersant of α-Si ₃ N ₄ , add it to the dispersion medium, dissolve it, add the dispersant solution to the above-mentioned multi-phase suspension, and then add Al ₂ O ₃ and Y ₂ O ₃ powder The body is dispersed evenly to obtain a mixed system;

(3) Transfer the mixed system obtained in step (2) to a ball mill tank for ball milling; the completed ball milling liquid is dried and sieved to obtain a mixed powder;

(4) Put the mixed powder described in step (3) into the mold for shaping, and then perform discharge plasma sintering.

Further, in step (1) or (2), the dispersion medium includes but is not limited to anhydrous ethanol or anhydrous methanol.

Further, in step (2), the dispersant includes but is not limited to polyethylene glycol, specifically polyethylene glycol 6000.

Further, in the step (3), ball milling balls are added according to the ball material weight ratio of 10:0.5 to 1.5, and ball milling is performed under a protective atmosphere for 40 to 50 hours; specifically, the protective atmosphere is nitrogen.

Further, in the step (3), the ball milling ball is cemented carbide ball YG6 or YG8.

Further, in the step (3), the drying method of the ball milling liquid includes but is not limited to one of normal pressure drying, vacuum drying, spray drying or freeze drying.

In a specific embodiment, the drying adopts vacuum drying at 80-120°C for 12-24 hours.

Further, in the step (3), the ball milling liquid is dried and sieved through a 100-120 mesh sieve to obtain a mixed powder.

Further, in the step (4), the discharge plasma sintering parameters: heating rate: before 1300°C, 90-110°C/min, above 1300°C, 30-50°C/min; sintering temperature 1650-1750 ℃; holding time 20-35min, respectively at 1600℃ and 10-17min after reaching the sintering temperature; axial pressure 25-35MPa.

In a specific implementation of the above preferred technical solution, the preparation method includes the following steps:

(1) Weigh α-Si ₃ N ₄ and TiC powder in proportion, add an appropriate amount of absolute ethanol as the dispersion medium, ultrasonically disperse and mechanically stir for 10-20 minutes to prepare α-Si ₃ N ₄ suspension and TiC Suspension, mix two suspensions to obtain a multi-phase suspension;

(2) Weigh 1-5wt% polyethylene glycol 6000 of α-Si ₃ N ₄ , dissolve it in absolute ethanol and add it to the multi-phase suspension, then add Al ₂ O ₃ and Y ₂ O ₃ powder in proportion body, ultrasonically disperse and mechanically stir for 30-50 minutes;

(3) Pour the final suspension obtained in step (2) into the ball milling tank, add ball milling balls according to the ball to material weight ratio of 10:1, conduct ball milling under a protective atmosphere for 48 hours, and place the ball milling liquid in a vacuum drying oven at 80-120°C. Dry for 12-24 hours, and then sieve through a 100-120 mesh sieve to obtain the mixed powder, which is sealed and stored for later use;

(4) Put the mixed powder obtained in step (3) into a graphite mold, and then put it into a discharge plasma sintering furnace for sintering after cold pressing.

A second aspect of the present invention provides Si ₃ N ₄ /TiC ceramic materials prepared by the method for preparing Si ₃ N ₄ /TiC ceramic materials based on discharge plasma sintering described in the first aspect.

A third aspect of the present invention provides applications of the Si ₃ N ₄ /TiC ceramic material described in the first aspect in the production of cutting tools, wear-resistant parts, plug-ins, and products for the aviation industry.

In order to enable those skilled in the art to understand the technical solution of the present invention more clearly, the technical solution of the present invention will be described in detail below with reference to specific examples. The raw materials involved in the following examples are all commercially available products.

Example 1

A method for preparing Si ₃ N ₄ /TiC ceramic materials based on spark plasma sintering (SPS). The volume percentage of raw material components is α-Si ₃ N ₄ 82%, TiC 10%, Al ₂ O ₃ 3%, Y ₂ O ₃ 5%.

Weigh α-Si ₃ N ₄ and TiC powder in proportion, add an appropriate amount of absolute ethanol as the dispersion medium, disperse ultrasonically and mechanically stir for 15 minutes to prepare α-Si ₃ N ₄ suspension and TiC suspension; add the above The two suspensions are mixed to obtain a multiphase suspension. Weigh 3wt% polyethylene glycol 6000 based on the weight of Si ₃ N ₄ powder, dissolve it in absolute ethanol and add it to the multi-phase suspension. Then add Al ₂ O ₃ and Y ₂ O ₃ powder in proportion, disperse with ultrasonic and Stir mechanically for 45 minutes; pour the final suspension obtained into the ball mill tank, add ball milling balls according to the weight ratio of balls to materials: 10:1, and conduct ball milling under nitrogen atmosphere for 48 hours.

The obtained ball milling liquid was dried in a vacuum drying oven at 110°C for 12 hours, and then sieved through a 100-mesh sieve to obtain a mixed powder. The obtained mixed powder was put into a graphite mold, and then placed in a discharge plasma after cold pressing. Hot press sintering is performed in the sintering furnace; discharge plasma sintering parameters: 100℃/min before 1300℃; 50℃/min from 1300℃-1450℃; 30℃/min from 1450℃-1600℃; 15min holding temperature at 1600℃; 1600℃-1700℃ ℃30℃/min; 1700℃ insulation for 10min; pressure 30MPa.

The ceramic material prepared in this example was cut into standard strip specimens of 3 mm × 4 mm × 35 mm, and then the strips were rough ground, ground, chamfered, and polished. The mechanical properties were tested and the results showed that the material's bending strength was 959MPa, the hardness was 15.21GPa, and the fracture toughness was 8.61MPa·M ^1/2 . From Figure 1, we can see the process of densification and crystal growth of spark plasma sintering Si ₃ N ₄ ceramic materials. Before 1200°C, the powder expands when heated, the lower pressure head moves downward, and the Z-axis displacement decreases. The densification process occurs after 1200°C. At this time, the lower pressure head moves up and the Z-axis displacement increases. When the temperature reaches 1700°C, the crystals begin to grow, the ceramic material begins to expand, and the Z-axis displacement decreases. According to Figure 2, it can be found that the phase composition of the sintered Si ₃ N ₄ /TiC ceramic material is β-Si ₃ N ₄ , TiC _0.3 N _0.7 and a small amount of α-Si ₃ N ₄ , among which TiC0.3N0.7 is mainly due to Si ₃ N ₄ and TiC react to form during the sintering process. And from Figure 2, it can be found that the crystallinity of various ceramic materials is good. Figure 3 shows the SEM image of the fracture surface of the Si ₃ N ₄ /TiC ceramic material. It can be found that the grains are uniform, no larger β-Si ₃ N ₄ is found, and the density is good, and no obvious pores are found. This is also Ceramic materials have excellent mechanical properties.

Example 2

A method for preparing Si ₃ N ₄ /TiC ceramic materials based on spark plasma sintering (SPS). The volume percentage of raw material components is α-Si ₃ N ₄ 82%, TiC 10%, Al ₂ O ₃ 3%, Y ₂ O ₃ 5%.

Weigh α-Si ₃ N ₄ and TiC powder in proportion, add an appropriate amount of absolute ethanol as the dispersion medium, disperse ultrasonically and mechanically stir for 15 minutes to prepare α-Si ₃ N ₄ suspension and TiC suspension; add the above The three suspensions were mixed to obtain a multiphase suspension. Weigh 3wt% of the dispersant based on the weight of Si ₃ N ₄ powder, dissolve it in absolute ethanol and add it to the multi-phase suspension. Then add Al ₂ O ₃ and Y ₂ O ₃ powder in proportion, disperse ultrasonically and mechanically stir for 45 minutes. ; Pour the final suspension obtained into the ball milling tank, add ball milling balls according to the weight ratio of balls to materials: 10:1, and conduct ball milling under nitrogen atmosphere for 48 hours.

The obtained ball milling liquid was dried in a vacuum drying oven at 110°C for 12 hours, and then sieved through a 100-mesh sieve to obtain a mixed powder. The obtained mixed powder was put into a graphite mold, and then placed in a discharge plasma after cold pressing. Hot press sintering is performed in the sintering furnace; discharge plasma sintering parameters: 100℃/min before 1300℃; 50℃/min from 1300℃-1450℃; 30℃/min from 1450℃-1600℃; 15min holding temperature at 1600℃; 1600℃-1650℃ ℃30℃/min; 1650℃ insulation for 10min; pressure 30MPa.

The ceramic material prepared in this example was cut into standard strip specimens of 3 mm × 4 mm × 35 mm, and then the strips were rough ground, ground, chamfered, and polished. The mechanical properties were tested and the results showed that the material's bending strength was 768MPa, its hardness was 15.81GPa, and its fracture toughness was 6.19MPa·M ^1/2 . And the introduction of TiC can better improve the electrical conductivity and EDM performance of Si ₃ N ₄ .

Example 3

A method for preparing Si ₃ N ₄ /TiC ceramic materials based on spark plasma sintering (SPS). The volume percentage of raw material components is α-Si ₃ N ₄ 82%, TiC 10%, Al ₂ O ₃ 3%, Y ₂ O ₃ 5%.

Weigh α-Si ₃ N ₄ and TiC powder in proportion, add an appropriate amount of absolute ethanol as the dispersion medium, disperse ultrasonically and mechanically stir for 15 minutes to prepare α-Si ₃ N ₄ suspension and TiC suspension; add the above The three suspensions were mixed to obtain a multiphase suspension. Weigh 3wt% of the dispersant based on the weight of Si ₃ N ₄ powder, dissolve it in absolute ethanol and add it to the multi-phase suspension. Then add Al ₂ O ₃ and Y ₂ O ₃ powder in proportion, disperse ultrasonically and mechanically stir for 45 minutes. ; Pour the final suspension obtained into the ball milling tank, add ball milling balls according to the weight ratio of balls to materials: 10:1, and conduct ball milling under nitrogen atmosphere for 48 hours.

The obtained ball milling liquid was dried in a vacuum drying oven at 110°C for 12 hours, and then sieved through a 100-mesh sieve to obtain a mixed powder. The obtained mixed powder was put into a graphite mold, and then placed in a discharge plasma after cold pressing. Hot press sintering is performed in the sintering furnace; discharge plasma sintering parameters: 100℃/min before 1300℃; 50℃/min from 1300℃-1450℃; 30℃/min from 1450℃-1600℃; 15min holding temperature at 1600℃; 1600℃-1700℃ ℃30℃/min; 1700℃ insulation for 15min; pressure 30MPa.

The ceramic material prepared in this example was cut into standard strip specimens of 3 mm × 4 mm × 35 mm, and then the strips were rough ground, ground, chamfered, and polished. The mechanical properties were tested and the results showed that the material's bending strength was 886MPa, the hardness was 13.73GPa, and the fracture toughness was 7.85MPa·M ^1/2 .

Example 4

A method for preparing Si ₃ N ₄ /TiC ceramic materials based on spark plasma sintering (SPS). The volume percentage of raw material components is α-Si ₃ N ₄ 82%, TiC 10%, Al ₂ O ₃ 4%, Y ₂ O ₃ 6%.

Weigh α-Si ₃ N ₄ and TiC powder in proportion, add an appropriate amount of absolute ethanol as the dispersion medium, disperse ultrasonically and mechanically stir for 15 minutes to prepare α-Si ₃ N ₄ suspension and TiC suspension; add the above The three suspensions were mixed to obtain a multiphase suspension. Weigh 3wt% of the dispersant based on the weight of Si ₃ N ₄ powder, dissolve it in absolute ethanol and add it to the multi-phase suspension. Then add Al ₂ O ₃ and Y ₂ O ₃ powder in proportion, disperse ultrasonically and mechanically stir for 45 minutes. ; Pour the final suspension obtained into the ball milling tank, add ball milling balls according to the weight ratio of balls to materials: 10:1, and conduct ball milling under nitrogen atmosphere for 48 hours;

The obtained ball milling liquid was dried in a vacuum drying oven at 110°C for 12 hours, and then sieved through a 100-mesh sieve to obtain a mixed powder. The obtained mixed powder was put into a graphite mold, and then placed in a discharge plasma after cold pressing. Hot press sintering is performed in the sintering furnace; discharge plasma sintering parameters: 100℃/min before 1300℃; 50℃/min from 1300℃-1450℃; 30℃/min from 1450℃-1600℃; 15min holding temperature at 1600℃; 1600℃-1700℃ ℃30℃/min; 1700℃ insulation for 10min; pressure 30MPa.

The ceramic material prepared in this example was cut into standard strip specimens of 3 mm × 4 mm × 35 mm, and then the strips were rough ground, ground, chamfered, and polished. The mechanical properties were tested and the results showed that the material's bending strength was 891MPa, the hardness was 13.21GPa, and the fracture toughness was 8.37MPa·M ^1/2 .

Example 5

A method for preparing Si ₃ N ₄ /TiC ceramic materials based on spark plasma sintering (SPS). The volume percentage of raw material components is α-Si ₃ N ₄ 82%, TiC 10%, Al ₂ O ₃ 3%, Y ₂ O ₃ 5%.

Weigh α-Si ₃ N ₄ and TiC powder in proportion, add an appropriate amount of absolute ethanol as the dispersion medium, disperse ultrasonically and mechanically stir for 15 minutes to prepare α-Si ₃ N ₄ suspension and TiC suspension; add the above The three suspensions were mixed to obtain a multiphase suspension. Weigh 3wt% of the dispersant based on the weight of Si ₃ N ₄ powder, dissolve it in absolute ethanol and add it to the multi-phase suspension. Then add Al ₂ O ₃ and Y ₂ O ₃ powder in proportion, disperse ultrasonically and mechanically stir for 45 minutes. ; Pour the final suspension obtained into the ball milling tank, add ball milling balls according to the weight ratio of balls to materials: 10:1, and conduct ball milling under nitrogen atmosphere for 48 hours.

The obtained ball milling liquid was dried in a vacuum drying oven at 110°C for 12 hours, and then sieved through a 100-mesh sieve to obtain a mixed powder. The obtained mixed powder was put into a graphite mold, and then placed in a discharge plasma after cold pressing. Hot press sintering is performed in the sintering furnace; discharge plasma sintering parameters: 100℃/min before 1300℃; 50℃/min from 1300℃-1450℃; 30℃/min from 1450℃-1600℃; 15min holding temperature at 1600℃; 1600℃-1700℃ ℃30℃/min; 1700℃ insulation for 10min; pressure 40MPa.

The ceramic material prepared in this example was cut into standard strip specimens of 3 mm × 4 mm × 35 mm, and then the strips were rough ground, ground, chamfered, and polished. The mechanical properties were tested and the results showed that the material's bending strength was 801MPa, the hardness was 14.63GPa, and the fracture toughness was 7.26MPa·M ^1/2 .

The above descriptions are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims (3)

1. Si based on spark plasma sintering ₃ N ₄ The preparation method of the TiC ceramic material is characterized by comprising the following steps: with Si ₃ N ₄ TiC is the reinforcing phase, al ₂ O ₃ And Y ₂ O ₃ The volume percentage of raw materials used as sintering auxiliary agent is as follows: alpha-Si ₃ N ₄ 82%，TiC 10%，Al ₂ O ₃ 3%，Y ₂ O ₃ 5%；

The preparation method specifically comprises the following steps:

weighing alpha-Si according to a proportion ₃ N ₄ Respectively adding proper amount of absolute ethyl alcohol as a dispersion medium into TiC powder, performing ultrasonic dispersion and mechanical stirring for 15min to obtain alpha-Si ₃ N ₄ A suspension, tiC suspension; mixing the two suspensions to obtain a complex phase suspension; weighing Si ₃ N ₄ Polyethylene glycol 6000 accounting for 3 weight percent of the powder is dissolved by absolute ethyl alcohol and added into the complex phase suspension, and then Al is added according to the proportion ₂ O ₃ And Y ₂ O ₃ Dispersing the powder by ultrasonic and mechanically stirring for 45min; pouring the obtained final suspension into a ball milling tank, adding ball milling balls according to the ball material weight ratio of 10:1, and performing ball milling for 48 hours in a nitrogen atmosphere;

drying the obtained ball milling liquid for 12 hours at 110 ℃ in a vacuum drying oven, sieving through a 100-mesh sieve to obtain mixed powder, filling the obtained mixed powder into a graphite mold, and placing the graphite mold into a discharge plasma sintering furnace for hot-press sintering after cold press molding; spark plasma sintering parameters: 100 ℃/min before 1300 ℃; 1300-1450 ℃ 50 ℃/min; 30 ℃/min at 1450-1600 ℃; preserving heat at 1600 ℃ for 15min; 30 ℃/min at 1600 ℃ to 1700 ℃; preserving heat at 1700 ℃ for 10min; the pressure is 30MPa.

2. Si based on spark plasma sintering as claimed in claim 1 ₃ N ₄ Si prepared by preparation method of TiC ceramic material ₃ N ₄ TiC ceramic material.

3. Si according to claim 2 ₃ N ₄ The TiC ceramic material is applied to the fields of production of cutting tools, wear-resistant parts, inserts and products for aviation industry.