CN116426795A - A kind of ceramic reinforced aluminum matrix composite material for automobile brake disc and preparation method thereof - Google Patents

Abstract

A ceramic reinforced aluminum-based composite material for an automobile brake disc and a preparation method thereof belong to the technical field of automobile material application. The aluminum-based electric composite material consists of reinforced phase titanium carbide and aluminum, wherein the reinforced phase titanium carbide is continuously and uniformly distributed in a three-dimensional space of matrix aluminum, the interface between the two phases is well combined without obvious reaction products, the volume fraction of the titanium carbide is 35-60%, and the balance is aluminum. The preparation method comprises the following steps: aluminum powder and titanium carbide powder are uniformly mixed, the aluminum-titanium carbide composite porous skeleton is prepared by hot pressing and sintering under the protection of gas or vacuum condition, and then metal aluminum is infiltrated at high temperature to obtain the aluminum-based composite material with light weight, high strength, wear resistance and good thermal conductivity, so that the requirement of a brake disc on the service performance of the material is met, and the light weight of an automobile is facilitated. The method is an industrial mature process, has the characteristics of safety, reliability and low energy consumption, and is convenient for industrialized mass production.

Description

A kind of ceramic reinforced aluminum matrix composite material for automobile brake disc and preparation method thereof

technical field

The invention belongs to the technical field of automobile material application, and in particular relates to a ceramic-reinforced aluminum-based composite material for automobile brake discs and a preparation method thereof.

Background technique

With the increasing development of the automobile industry, automobile lightweight is of great significance to reduce automobile quality, fuel consumption, emission reduction and environmental protection. The brake disc is an important braking part of the car, which plays the role of deceleration or parking, and its braking effect depends on the performance of the material. Aluminum-based composite materials have light weight, high strength, good thermal conductivity and good wear resistance, which not only meet the service performance requirements of brake discs, but also help to reduce the weight of automobiles.

Titanium carbide is often used as a reinforcing phase to improve the mechanical properties of aluminum because of its high modulus, high hardness, light weight and good lattice matching relationship with aluminum. Based on the current preparation process, such as powder metallurgy, hot isostatic pressing, spark plasma sintering and liquid manufacturing, etc., the problem of agglomeration and distribution of the reinforcing phase on the aluminum matrix is a key issue that is unfavorable to the mechanical properties and wear resistance of the composite material; Secondly, the addition of titanium carbide in the reinforcing phase is small, and it is dispersed in the matrix, which not only has a low strengthening effect on the mechanical properties of the material, but also leads to a limited increase in hardness and strength, and there is no bonding connection between the reinforcing phases. During the process, the reinforcing phase is easy to peel off from the matrix, resulting in the inability to significantly improve the wear resistance.

At present, regarding a silver-based electrical contact material reinforced by a shape memory effect alloy and its preparation method, Patent 1 (CN 115094280A) discloses an aluminum-based composite material for automobile brake discs and its preparation method; Patent 2 (CN115058619A) discloses a Nano-titanium carbide reinforced 2024 aluminum-based composite material and its preparation method; patent 3 (CN 107641743A) a nano-titanium carbide-reinforced aluminum-silicon-based composite material and its preparation method; patent 4 (CN 115505779A) the invention name is in-situ generation of aluminum matrix Preparation method of titanium carbide composite material.

Patents 1-4 all adopt the preparation process of smelting and casting. The process feature is that the composition of raw materials will inevitably introduce impurities (such as oxide inclusions), which will agglomerate at the grain boundaries of the matrix aluminum, affecting the conduction of stress and frictional heat. It is prone to brittle fracture and affects the mechanical properties of the material. The doping of impurities makes the hardness of the composite material low, easy to wear, poor wear resistance, and the bonding strength between impurities and the matrix is low. During the friction and wear process, impurities Because it cannot be coordinated with the matrix, it is more likely to be worn, resulting in spalling and forming voids, which promote crack initiation and expansion under the action of stress, and eventually fail; secondly, the content of titanium carbide is small, and titanium carbide is microscopic. The form is distributed in the aluminum matrix, resulting in low hardening efficiency of the material, poor wear resistance, and reduced service life of the material; while the content of the added titanium carbide is higher than the content of the matrix, it will cause agglomeration, and it is difficult to fully integrate the two phases. Their respective advantages (such as thermal conductivity and toughness of aluminum and high hardness and wear resistance of titanium carbide).

Contents of the invention

Aiming at the problems existing in the prior art, the present invention provides a ceramic-reinforced aluminum-based composite material for automobile brake discs and a preparation method thereof, the purpose of which is to obtain a light-weight Aluminum matrix composite material with high strength, wear resistance and good thermal conductivity. The invention provides titanium carbide-reinforced aluminum-based composite material, which is composed of titanium carbide and aluminum or aluminum alloy without obvious reaction, the volume fraction of titanium carbide is 35-60%, and the balance is aluminum. The titanium carbide porous skeleton is prefabricated by the hot pressing sintering process, and metal aluminum is infiltrated at high temperature to obtain a titanium carbide reinforced aluminum matrix composite material, in which the reinforcement phase titanium carbide is uniformly distributed in the aluminum matrix in the form of continuous space grids, and the reinforcement phase Titanium carbide continuous can obtain high strengthening efficiency and high damage tolerance. And the porous composite skeleton prepared by hot pressing titanium carbide and aluminum powder or aluminum alloy powder can effectively adjust the proportion of the two phases in the aluminum matrix composite material, which not only can reduce the energy consumption of sintered titanium carbide, but also can be improved by adding different shapes of aluminum powder , can adjust the microstructure of the aluminum matrix composite material, and then adjust the different properties of the material, and finally realize the synergistic improvement of the material strength, hardness, wear resistance and thermal conductivity. It has the effect of reducing friction and lubricating, reducing the wear of composite materials, and the continuous aluminum matrix is conducive to heat dissipation of materials, avoiding thermal brittle fracture of materials, and improving the fatigue life of materials.

The preparation process adopts hot pressing and sintering to prepare aluminum-titanium carbide composite porous framework, so that the nano-titanium carbide can be uniformly distributed in three-dimensional space, and then infiltrate the metal aluminum at high temperature, and indirectly sinter the titanium carbide particles to make the titanium carbide form a spatial grid. The form of continuous distribution in the aluminum matrix, the spatial configuration has high strengthening efficiency, damage tolerance, and effectively exerts the respective performance characteristics of the two phases.

In order to achieve the above object, the technical scheme adopted in the present invention is as follows:

A kind of preparation method of ceramic reinforced aluminum matrix composite material for automobile brake disc of the present invention comprises the following steps:

Step 1: ball milling and mixing the aluminum powder and nano-titanium carbide powder to obtain a mixed slurry; standing the mixed slurry for precipitation, separating the solid and liquid, and drying to obtain an aluminum-titanium carbide mixed powder;

Step 2, hot pressing and sintering

Put aluminum-titanium carbide mixed powder or nano-titanium carbide powder into a hot-pressing mold, carry out hot-pressing sintering in a vacuum environment or a protective atmosphere, then heat-preserve and pressure-holding treatment, and cool down with the furnace to obtain a porous skeleton;

Step 3, high temperature infiltration of metal aluminum:

Put the porous skeleton and metal aluminum in step 2 into a graphite crucible, place in a vacuum environment or a protective atmosphere for infiltration treatment and heat preservation, and then cool with the furnace to obtain a nano-TiC reinforced aluminum matrix composite material.

The mixing time of ball milling in step 1 is at least 24h, and the ball milling speed is 10～60rpm; Ball milling is selected dry method or wet method ball milling; The solvent that wet method ball milling adopts is alcohol, and the ball milling medium that selects is zirconia ball, and material-ball ratio is (5 -10): 1;

The aluminum powder and nano-titanium carbide powder described in step 1, wherein the aluminum powder is flaky or spherical aluminum powder, or flaky or spherical aluminum alloy powder, and the particle size of the aluminum powder or aluminum alloy powder is 5-50 μm; When the aluminum powder or aluminum alloy powder is flake, the sheet diameter is 5-30 μm, and the thickness is 0.1-2 μm; when the aluminum powder or aluminum alloy powder is spherical, the spherical diameter is 5-15 μm; the particles of nano-titanium carbide The diameter is 20-100nm; the volume fraction of the aluminum powder in the mixed powder is 0-50vol%;

The drying described in step 1 is: natural air drying or placement in a fume hood to volatilize;

The hot-pressing sintering described in step 2 is specifically, from room temperature to the hot-pressing sintering temperature at a heating rate of 5-10°C/min, when the temperature rises to the sintering temperature, the pressure is loaded to 5MPa, and the heat preservation and pressure holding time is 1h, and then Cool with the furnace and pressurize to room temperature; the porous skeleton is specifically, when the aluminum-titanium carbide mixed powder is loaded into the hot-pressing mold, the obtained porous skeleton is a composite porous skeleton of aluminum-titanium carbide, hot-pressed and sintered The temperature of the aluminum-titanium carbide composite porous skeleton is 550-600°C; when nanometer titanium carbide powder is loaded into the hot-pressing mold, the obtained porous skeleton is a titanium carbide porous skeleton, wherein the hot-pressed sintered titanium carbide porous skeleton The temperature is 1000-1300℃;

The vacuum degree of the vacuum environment described in step 2 and step 3 is not higher than 10 ^-3 Pa, and the protective atmosphere is argon;

The mass ratio of the composite porous framework of aluminum-titanium carbide and metal aluminum described in step 3 is not less than 1:3;

The infiltration described in step 3 is specifically, rising from room temperature at a heating rate of 5°C/min to the infiltration temperature of 900-1000°C, and the holding time is at least 0.5h;

The ceramic-reinforced aluminum-based composite material for brake discs of the present invention includes a reinforcing phase titanium carbide and a matrix aluminum; the reinforcing phase titanium carbide of the composite material is evenly distributed in the matrix aluminum and has no obvious defects. Among them, the volume fraction of the reinforcing phase titanium carbide is: 35%～60%, the balance is aluminum;

The hardness of the ceramic reinforced aluminum matrix composite material for the brake disc is 1.8-2.1GPa;

The bending strength of the ceramic reinforced aluminum matrix composite material for the brake disc is 280-580MPa;

The fracture toughness of the ceramic reinforced aluminum matrix composite material for the brake disc is 10-12MPa·m1/2;

The thermal conductivity of the ceramic reinforced aluminum matrix composite material for the brake disc is 55-130 W/mK.

Compared with the prior art, a ceramic-reinforced aluminum-based composite material for automobile brake discs of the present invention and a preparation method thereof have the following beneficial effects:

The invention provides a ceramic-reinforced aluminum-based composite material for automobile brake discs and a preparation method thereof. In terms of raw materials, light-weight titanium carbide and aluminum are used to meet the characteristics of lightweight automobiles. The preparation process is to use hot pressing sintering to prefabricate the composite porous framework of titanium carbide and aluminum. The sintering temperature used here is to sinter the metal aluminum to achieve the purpose of forming the composite porous framework and realize the uniform distribution of titanium carbide powder in three dimensions. , which greatly reduces the energy consumption required for direct sintering of titanium carbide powder, and then infiltrates metal aluminum at high temperature to obtain an aluminum matrix composite material, in which nano-titanium carbide can achieve ceramic phase between titanium carbide particles during high-temperature infiltration The sintering and the promotion of the infiltration of metal aluminum are microscopically manifested as continuous distribution of titanium carbide in the aluminum matrix, and its structure has the characteristics of high strengthening efficiency and damage tolerance. It can play a lubricating effect, thereby reducing the amount of wear of the composite material, which is conducive to improving the fatigue wear life of the material, especially by adjusting the amount of aluminum powder added to the mixed powder (0-50vol%) and then improving the strength of the aluminum matrix composite material , hardness, toughness and thermal conductivity are adjusted to meet the performance requirements of brake discs under complex friction conditions.

Description of drawings

Fig. 1 is the microstructure diagram of the prepared Al-TiC ceramic reinforced aluminum matrix composite material in Example 1 of the present invention;

Fig. 2 is embodiment 1 of the present invention, the three-point bending stress-strain curve of prepared Al-TiC ceramics reinforced aluminum matrix composite;

Fig. 3 is the microstructure diagram of the prepared Al-60vol%TiC ceramic reinforced aluminum matrix composite material in Example 2 of the present invention;

Fig. 4 is the XRD result of the prepared Al-60vol%TiC ceramic reinforced aluminum matrix composite material in Example 2 of the present invention;

Fig. 5 is the embodiment 2 of the present invention, the three-point bending stress-strain curve of the prepared Al-60vol% TiC ceramic reinforced aluminum matrix composite;

Fig. 6 is the microstructure diagram of the prepared Ag-45vol% TiC ceramic reinforced aluminum matrix composite material in Example 3 of the present invention;

Fig. 7 is embodiment 3 of the present invention, the three-point bending stress-strain curve of prepared Ag-45vol%TiC ceramic reinforced aluminum matrix composite material;

Figure 8 is a microstructure diagram of the prepared Ag-40vol%TiC ceramic reinforced aluminum matrix composite material in Example 4 of the present invention;

Fig. 9 is the embodiment 4 of the present invention, the three-point bending stress-strain curve of the prepared Ag-40vol%TiC ceramic reinforced aluminum matrix composite;

Fig. 10 is the _KJ -R curve of the in-situ fracture toughness test of Example 3 and Example 4 of the present invention.

Detailed ways

In order to further explain the technical means and effects of the present invention to achieve the intended purpose of the invention, the specific implementation, structure, features and effects of the application according to the present invention will be described in detail below in conjunction with the accompanying drawings and preferred embodiments. . In the following description, different "one embodiment" or "embodiment" do not necessarily refer to the same embodiment. Furthermore, the particular features, structures, or characteristics of one or more embodiments may be combined in any suitable manner.

Concrete scheme of the present invention is as follows:

The embodiments of the present invention provide a ceramic reinforced aluminum matrix composite material for automobile brake discs and a preparation method thereof. Among them, the ceramic-reinforced aluminum-based composite material is uniformly mixed with micron-sized aluminum powder and nano-titanium carbide powder, and subjected to hot-pressing sintering to obtain an aluminum-titanium carbide composite porous skeleton, and finally infiltrated with metal aluminum to obtain titanium carbide-reinforced Aluminum-based composite material; the volume fraction of titanium carbide powder in the mixed powder is 30-70vol%, and the balance is aluminum powder or aluminum alloy powder. The temperature of hot pressing and sintering mixed powder is 550-600°C, the pressure is 5MPa, the heat preservation and pressure holding time is 1h, the temperature of infiltrated metal aluminum is 900-1000°C, and the heat preservation time is at least 0.5h.

Below by concrete experiment embodiment, the present invention is further described as follows:

In the following examples, the same hot-pressing sintering furnace and infiltration tube furnace were used to prepare aluminum-titanium carbide composite porous skeletons and titanium carbide-reinforced aluminum matrix composite materials, respectively.

Example 1

In this embodiment, a ceramic-reinforced aluminum-based composite material for automobile brake discs and a preparation method thereof are used, including the following preparation steps:

Step 1, preparation of TiC skeleton

Weigh 40g of TiC powder with an average particle size of 50nm and put it into the prepared hot-pressing mold, heat it from room temperature to 1200°C in a vacuum environment or a protective atmosphere, heat-preserve the mixed powder for 1 hour, and cool it with the furnace to obtain carbonization Titanium porous skeleton;

Step 2, high temperature infiltration aluminum block:

Put the titanium carbide porous skeleton and aluminum block into a graphite crucible, place it in a vacuum environment or a high-temperature furnace with a protective atmosphere, raise it from room temperature to 900 ° C, keep it for 1 hour and cool it with the furnace to obtain an Al-80vol% TiC composite material.

Figure 1 is a microstructure diagram of the Al-80vol% TiC ceramic reinforced aluminum matrix composite material obtained in Example 1 of the present invention. It can be seen that there are no obvious defects in the composite material and the titanium carbide is evenly distributed in the matrix. Fig. 2 is the three-point bending stress-strain curve of the Al-80vol% TiC ceramic reinforced aluminum matrix composite material prepared in Example 1 of the present invention, its bending strength is 570MPa, and the measured thermal conductivity at room temperature is 58.4W/mK, because The ceramic content is much higher than the aluminum content of the matrix, and the hardness, strength and wear resistance of the material are significantly improved, which can increase the service life of the brake disc, but the toughness and thermal conductivity of the composite material are lost, which may affect the braking performance of the brake disc. heat transfer efficiency of the process.

Example 2

In this embodiment, a ceramic-reinforced aluminum-based composite material for automobile brake discs and a preparation method thereof are used, including the following preparation steps:

Step 1, prepare Al-TiC mixed powder:

Weigh 10.8g of 5083Al alloy powder with an average particle size of 24μm, 29.4g of TiC powder with an average particle size of 50nm and 80g of zirconium balls, add alcohol with a liquid level higher than the mixed powder, and mix on a rolling ball mill for 48 hours. After the mixing is completed, Pour the mixed slurry into a beaker, after powder precipitation, remove the upper layer of alcohol, and then place it in a fume hood for natural drying treatment, and the alcohol is volatilized to obtain Al-60vol% TiC mixed powder;

Step 2, hot pressing and sintering mixed powder:

Put the Al-60vol% TiC mixed powder into the prepared hot-pressing mold, heat from room temperature to 580°C in a vacuum environment or a protective atmosphere, heat the mixed powder for 1 hour, and cool it with the furnace to obtain aluminum-carbide Composite porous framework of titanium;

Step 3, high temperature infiltration of 5083 aluminum alloy:

Put the aluminum-titanium carbide composite porous skeleton and the 5083 aluminum alloy block into a graphite crucible, place it in a vacuum environment or a high-temperature furnace with a protective atmosphere, raise it from room temperature to 900 ° C, keep it for 1 hour and cool it with the furnace to obtain Al- 60vol% TiC composite.

Fig. 3 is the microstructure diagram of the Al-60vol% TiC ceramic reinforced aluminum matrix composite material obtained in Example 2 of the present invention. It can be seen that there are no obvious defects in the composite material and the titanium carbide is evenly distributed in the matrix. It is obtained through characterization that Al- The hardness value of the 60vol% TiC composite material is 2.1 ± 0.21GPa. Fig. 4 is the XRD result of the Al-60vol% TiC ceramic reinforced aluminum matrix composite material obtained in Example 2 of the present invention. It can be seen that when the two phases are infiltrated at high temperature, there is no Other reaction products, Figure 5 is the embodiment 2 of the present invention, the three-point bending stress-strain curve of the prepared Al-60vol% TiC ceramic reinforced aluminum matrix composite material, its bending strength is 337MPa, and the measured thermal conductivity at room temperature is 97.5 W/mK.

Example 3

In this embodiment, a ceramic-reinforced aluminum-based composite material for automobile brake discs and a preparation method thereof are used, including the following preparation steps:

Step 1, prepare Al-TiC mixed powder:

Weigh 11.4g of pure aluminum powder with an average flake size of 10-20μm, 24.5g of TiC powder with an average particle size of 50nm and 70g of zirconium balls, add alcohol whose liquid level is higher than that of the mixed powder, mix on a rolling ball mill for 48 hours, and mix After completion, pour the mixed slurry into a beaker, remove the upper layer of alcohol after powder precipitation, and then place it in a fume hood for natural drying, and the alcohol is volatilized to obtain a mixed powder;

Step 2, hot pressing and sintering mixed powder:

Put the mixed powder into the prepared hot-pressing mold, heat from room temperature to 580°C in a vacuum environment or a protective atmosphere, heat-preserve the mixed powder for 1 hour, and cool down with the furnace to obtain a composite porous skeleton of aluminum-titanium carbide ;

Step 3, high temperature infiltration of metal aluminum:

Put the aluminum-titanium carbide composite porous skeleton and metal aluminum block into a graphite crucible, place it in a vacuum environment or a high-temperature furnace with a protective atmosphere, raise it from room temperature to 900 ° C, keep it warm for 1 hour and cool with the furnace to obtain Al-50vol %TiC composite.

Fig. 6 is a microstructure diagram of the Al-50vol% TiC ceramic reinforced aluminum matrix composite material obtained in Example 3 of the present invention. It can be seen that the flake aluminum powder in the composite material is in the direction perpendicular to the pressure direction, and the orientation is uniformly distributed on the aluminum matrix. Among them, it is obtained through characterization that the hardness value of the Al-50vol%TiC composite material is 1.8±0.22GPa. Figure 7 is the three-point bending stress-strain curve of the prepared Al-50vol%TiC composite material in Example 3 of the present invention. The strength is 302MPa, and the measured thermal conductivity at room temperature is 119.2W/mK.

Example 4

In this embodiment, a ceramic-reinforced aluminum-based composite material for automobile brake discs and a preparation method thereof are used, including the following preparation steps:

Step 1, prepare Al-TiC mixed powder:

Weigh 16.2g of pure aluminum balls with an average diameter of 10μm, 19.6g of TiC powder with an average particle size of 50nm and 70g of zirconium balls, add alcohol whose liquid level is higher than that of the mixed powder, and mix on a rolling ball mill for 24 hours. , pour the mixed slurry into a beaker, after powder precipitation, remove the upper layer of alcohol, then place it in a fume hood for natural drying, and the alcohol is volatilized to obtain a mixed powder;

Step 2, hot pressing and sintering mixed powder:

Put the mixed powder into the prepared hot-pressing mold, heat from room temperature to 550°C in a vacuum environment or a protective atmosphere, heat-preserve the mixed powder for 1 hour, and cool down with the furnace to obtain a composite porous skeleton of aluminum-titanium carbide ;

Step 3, high temperature infiltration of metal aluminum:

Put the aluminum-titanium carbide composite porous skeleton and metal aluminum block into a graphite crucible, place it in a vacuum environment or a high-temperature furnace with a protective atmosphere, raise it from room temperature to 1000°C, keep it warm for 1 hour and cool with the furnace to obtain Al-40vol %TiC composite.

Fig. 8 is a microstructure diagram of the Al-40vol% TiC ceramic reinforced aluminum matrix composite material obtained in Example 4 of the present invention. It can be seen that there are no obvious defects in the composite material, and titanium carbide is evenly distributed in the matrix in the form of grids, and the matrix Aluminum retains a spherical shape, and the volume fraction of aluminum in the composite material can be adjusted. Through characterization, the hardness value of the Al-40vol%TiC composite material is 1.6±0.1GPa. Figure 9 is the Al-40vol% obtained in Example 3 of the present invention The three-point bending stress-strain curve of %TiC ceramic reinforced aluminum matrix composite material, its bending strength is 285MPa, Fig. 10 is the K _J of the in-situ fracture toughness test of the ceramic reinforced aluminum matrix composite material prepared in Example 3 and Example 4 of the present invention -R curve, the results show that the crack propagation in the aluminum matrix composite material prepared by the present invention is relatively stable, showing a rising R curve behavior, and its fracture toughness values are 12.5MP·m ^1/2 and 11.6MP·m ^1/2 respectively, The measured thermal conductivity at room temperature is 138.8W/mK.

Example 5

The same as Example 1, the difference is that the nano-titanium carbide powder is hot-pressed and sintered at 1400 ° C, the pressure is 30 MPa, and the heat preservation and pressure holding time is 2 hours. Too many closed cells are formed in the skeleton, which affects the infiltration of aluminum metal, resulting in hole defects in the composite material, resulting in poor strength, hardness and wear resistance of the aluminum matrix composite material;

Comparative example 1

The same as Example 2, the difference is that there is no ball milling process in Example 2, only two phases are simply mixed, and the uniformity of the mixed powder is poor, so that the aluminum-rich region of the composite material has poor wear resistance and is prone to wear and pits. Not only the thermal conductivity is low, but also the braking performance of the brake disc is poor, and the agglomeration of titanium carbide and the difference in the modulus of the two phases are relatively large, which affects the stress conduction of the composite material, resulting in cracking of the two-phase interface and premature failure, and its service performance cannot be satisfied with the actual performance. need.

Comparative example 2

The same as Example 2, the difference is that step 2 adopts hot pressing and sintering temperature of 650°C, the aluminum powder in the mixed powder will be extruded from the graphite mold due to the high temperature, resulting in low aluminum content in the porous composite skeleton, and then it is impossible to control the aluminum The aluminum content in the matrix composite material makes it impossible to improve the thermal conductivity of the material, which is not conducive to the heat dissipation of the material during the friction process, resulting in thermal brittle fracture, and ultimately leads to material failure.

Comparative example 3

Same as Example 2, the difference is that step 2 uses hot pressing and sintering pressure of 20 MPa, the aluminum powder in the mixed powder will cause low porosity of the composite skeleton due to excessive pressure, and then cannot control the aluminum matrix composite material. Aluminum content, and the phenomenon that the hard phase titanium carbide is pressed out of the soft phase aluminum out of the titanium carbide particle gap to form titanium carbide agglomeration, which not only reduces the thermal conductivity of the material but also increases the brittleness of the material, making it difficult to cooperate Improve and regulate material properties.

Comparative example 4

The same as Example 2, the difference is that in step 3, the porous composite skeleton of titanium carbide and aluminum and the aluminum block are directly placed at 900 ° C for infiltration treatment, without vacuum environment and argon protection, the aluminum in the composite material Alumina is oxidized to form a brittle phase, and the composition of the material changes, making the hardness, strength, toughness, thermal conductivity and other properties of the composite material deteriorate.

The above descriptions are only preferred embodiments of the present invention, and do not limit the present invention in any form. Any simple modifications, equivalent changes and modifications made to the above embodiments according to the technical essence of the present invention still belong to the present invention. within the scope of the technical program.

Claims (10)

1. A ceramic-reinforced aluminum-based composite material for automobile brake discs, characterized in that the ceramic-reinforced aluminum-based composite material for brake discs comprises a reinforcing phase of titanium carbide and matrix aluminum. 2. The ceramic-reinforced aluminum-matrix composite material for automobile brake discs according to claim 1, wherein the reinforcing phase titanium carbide is evenly distributed in the matrix aluminum and has no obvious defects, wherein the reinforcing phase titanium carbide The volume fraction of aluminum is 35% to 60%, and the balance is aluminum. 3. The ceramic-reinforced aluminum-based composite for automobile brake discs according to claim 1, wherein the hardness of the ceramic-reinforced aluminum-based composite for brake discs is 1.8-2.1 GPa, and the bending strength is 280-2.0 GPa. 580MPa, fracture toughness of 10-12MPa·m ¹ / ₂ , thermal conductivity of 55-130W/mK. 4. A preparation method based on the ceramic-reinforced aluminum-based composite material for automobile brake discs according to claim 1-3, characterized in that, comprising the following steps: Step (1): ball milling and mixing aluminum powder and nano-titanium carbide powder to obtain a mixed slurry; allowing the mixed slurry to stand for precipitation, and drying after solid-liquid separation to obtain an aluminum-titanium carbide mixed powder; Step (2), hot pressing sintering: Put aluminum-titanium carbide mixed powder or nano-titanium carbide powder into a hot-pressing mold, carry out hot-pressing sintering in a vacuum environment or a protective atmosphere, then heat-preserve and pressure-holding treatment, and cool down with the furnace to obtain a porous skeleton; Step (3), high temperature infiltration of metal aluminum: Put the porous skeleton and metal aluminum in step 2 into a graphite crucible, place it in a vacuum environment or a protective atmosphere for infiltration treatment and heat preservation, and then cool with the furnace to obtain a nano-TiC reinforced aluminum matrix composite material. 5. the preparation method of ceramic reinforced aluminum matrix composite material for automobile brake disc according to claim 4, is characterized in that, the aluminum powder described in step (1) is flake, spherical aluminum powder, or flake, spherical aluminum Alloy powder, when the aluminum powder or aluminum alloy powder is flake, the sheet diameter is 5-30 μm, and the thickness is 0.1-2 μm; when the aluminum powder or aluminum alloy powder is spherical, the ball diameter is 5-15 μm; nano-carbonization The particle diameter of the titanium is 20-100nm; the volume fraction of the aluminum powder in the mixed powder is 0-50vol%. 6. the preparation method of ceramic reinforced aluminum matrix composite material for automobile brake disc according to claim 4, is characterized in that, the ball mill described in step (1) selects dry method or wet method ball mill for use; The solvent that wet method ball mill adopts is Alcohol, the ball milling medium is zirconia balls, the material-ball ratio is (5-10):1. 7. The preparation method of ceramic-reinforced aluminum matrix composites for automobile brake discs according to claim 4, characterized in that, the mixing time of ball milling in step (1) is at least 24h, and the ball milling speed is 10～60rpm; Step 1 Drying as described in: natural air drying or volatilization in a fume hood. 8. The method for preparing ceramic-reinforced aluminum-based composites for automobile brake discs according to claim 4, characterized in that the hot-pressing sintering in step (2) is specifically, from room temperature at a heating rate of 5-10°C/ min to the hot pressing sintering temperature, when the temperature rises to the sintering temperature, the pressure is loaded to 5MPa, the heat preservation and pressure holding time is 1h, and then cooled with the furnace and the pressure is kept to room temperature, the porous skeleton is specifically, when loaded into the hot press When the aluminum-titanium carbide mixed powder in the mold is used, the obtained porous skeleton is a composite porous skeleton of aluminum-titanium carbide, and the temperature of the hot-pressed sintered composite porous skeleton of aluminum-titanium carbide is 550-600°C; When nanometer titanium carbide powder is used in the mold, the obtained porous framework is titanium carbide porous framework, wherein the temperature for hot pressing and sintering the titanium carbide porous framework is 1000-1300°C. 9. The method for preparing ceramic-reinforced aluminum matrix composites for automobile brake discs according to claim 4, wherein the vacuum degree of the vacuum environment in steps (2) and (3) is not higher than 10 ^-3 Pa , the protective atmosphere is argon. 10. the preparation method of ceramic reinforced aluminum matrix composite material for automobile brake disc according to claim 4, is characterized in that, the mass ratio of the composite porous framework of aluminum-titanium carbide described in step (3) and metal aluminum is not low 1:3; the infiltration is specifically, from room temperature at a heating rate of 5°C/min to the infiltration temperature of 900-1000°C, and the holding time is at least 0.5h.

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