Ceramic particle reinforced iron-based composite material and preparation method thereof

Abstract

The present invention discloses a ceramic particle reinforced iron-based composite material and a preparation method thereof. The ceramic particle reinforced iron-based composite material comprises the following raw material components, calculated by mass percentage: 10-20% Cr7C3, 8-30% TiC, and the balance Fe. Compared with the traditional sintering process, the present invention uses a spark plasma sintering process with a higher efficiency ratio, thereby reducing energy consumption and environmental impact, while significantly shortening the preparation time, improving production efficiency, and sintering at a lower temperature, which also avoids or reduces overheating and grain coarsening of the material. Compared with cast high-chromium cast iron, the ceramic particle reinforced iron-based composite material obtained by the preparation method of the present invention has higher hardness and better wear resistance. In addition, the preparation method of the present invention has a simple process and low cost, is suitable for industrial production, and can be widely used in the fields of mining, metallurgy and drilling engineering, and therefore has broad application prospects.

Description

Technical Field

[0001] The present invention belongs to the technical field of metal-based composite materials, and in particular relates to a ceramic particle reinforced iron-based composite material and a preparation method thereof. Background Art

[0002] Particle-reinforced iron-based composites primarily refer to material systems in which ceramic particles are dispersed throughout an iron matrix as a reinforcement phase. These composites offer advantages such as low cost, relatively simple preparation, isotropic properties, and ease of secondary processing. The ceramic particles can significantly improve the mechanical and friction and wear properties of the matrix material.

[0003] The traditional methods for preparing particle-reinforced iron-based composite materials mainly include: powder metallurgy, surface cladding and in-situ synthesis. However, traditional preparation processes often form excessive carbide phases and intermetallic compounds, which significantly reduce the material performance and thus affect the service life. Moreover, the surface cladding method is only suitable for the preparation of high-wear-resistant surface coatings and cannot be used to prepare larger-sized bulk materials. As an emerging rapid preparation method, spark plasma sintering technology has attracted a lot of attention due to its advantages of fast, low temperature, density and low energy consumption. Therefore, it is very necessary to explore the use of spark plasma sintering methods to quickly prepare ceramic particle-reinforced iron-based composite materials, so as to meet the needs of a large number of applications in mining, metallurgy, drilling and other fields.

[0004] TiC has excellent physical and chemical properties, including low density, high melting point, high hardness, wear resistance, corrosion resistance, and good stability. TiC, with its face-centered cubic structure, exhibits excellent wettability with the iron matrix at high temperatures and does not chemically react. Cr7C3 also has numerous advantages, including a high melting point, high hardness, wear resistance, and good stability. Therefore, the present invention, using TiC and Cr7C3 as reinforcing phases, is expected to produce a ceramic particle-reinforced iron-based composite material with excellent properties such as higher hardness, high temperature resistance, and wear resistance. This composite material can then be used in wear-resistant tools, tooling, molds, and parts in the mining, metallurgy, and drilling industries, as well as sealing rings for various pipes and pumps. Summary of the Invention

[0005] In view of the problems existing in the background technology, the purpose of the present invention is to provide a ceramic particle reinforced iron-based composite material and a preparation method thereof.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A first aspect of the present invention provides a ceramic particle reinforced iron-based composite material, comprising the following raw material components by mass percentage: 10-20% Cr7C3, 8-30% TiC, and the balance being Fe powder.

[0008] A second aspect of the present invention provides a method for preparing the above-mentioned ceramic particle reinforced iron-based composite material, comprising the following steps:

[0009] S1. Weigh Cr7C3 powder, TiC powder and Fe powder according to the formula, mix and ball mill to obtain a mixed powder;

[0010] S2. The obtained mixed powder is placed into a graphite mold and pressed to ensure that the powder particles are tightly packed and the upper and lower surfaces are flat;

[0011] S3. Placing the pressed mold in a spark plasma sintering furnace for sintering to obtain a ceramic particle reinforced iron-based composite material.

[0012] Preferably, the particle sizes of the Cr7C3 powder, TiC powder and Fe powder are all 240 mesh to 1340 mesh.

[0013] Preferably, in step S1, the ball milling conditions are: ball milling speed of 200-300 r / min, ball-to-material ratio of 1-10:1, ball milling time of 12-18 h, and the grinding ball material is zirconia.

[0014] Preferably, in step S3, the specific process of the sintering treatment is: placing the pressurized mold in a spark plasma sintering furnace, evacuating to below 10 Pa, raising the temperature to 1100-1300°C at a heating rate of 80-100°C / min for sintering, keeping warm for 20-40 minutes, and maintaining the system sintering pressure at 30-40 MPa during the insulation process, and then cooling.

[0015] Further preferably, the sintering temperature is 1100-1200° C., and the system sintering pressure is 30-35 MPa;

[0016] Preferably, the cooling is to below 100°C.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] (1) Compared with the traditional sintering process, the spark plasma sintering process used in the present invention has a higher efficiency ratio, thereby reducing energy consumption and environmental impact. At the same time, by utilizing the spark plasma sintering process, the preparation time is greatly shortened, the production efficiency is improved, and the sintering is performed at a lower temperature, which also avoids or reduces the overheating of the material and the coarsening of the grains.

[0019] (2) Compared with as-cast high-chromium cast iron, the ceramic particle-reinforced iron-based composite material obtained by the preparation method of the present invention has higher hardness and better wear resistance.

[0020] (3) The preparation method of the present invention has a simple process and low cost, is suitable for industrial production, and is expected to further reduce the price of high-performance wear-resistant steel materials, and can be widely used in the fields of mining, metallurgy and drilling engineering, thus having broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 1 is a microstructure diagram of the ceramic particle reinforced iron-based composite material prepared in Example 1;

[0023] Figure 2 2 is a microstructure diagram of the ceramic particle reinforced iron-based composite material prepared in Example 2;

[0024] Figure 3 3 is a microstructure diagram of the ceramic particle reinforced iron-based composite material prepared in Example 3;

[0025] Figure 4 This is a microstructure diagram of the ceramic particle reinforced iron-based composite material prepared in Example 4. DETAILED DESCRIPTION

[0026] In the following description, specific details such as specific system structures and technologies are provided for the purpose of illustration rather than limitation to facilitate a thorough understanding of the embodiments of the present invention. However, it should be clear to those skilled in the art that the present invention may also be implemented in other embodiments without these specific details.

[0027] Example 1

[0028] A ceramic particle reinforced iron-based composite material comprises the following raw material components, calculated by mass percentage: 10% Cr7C3, 20% TiC, and the balance Fe. The preparation method comprises the following steps:

[0029] S1. Weigh Cr7C3 powder (325 mesh), TiC powder (325 mesh) and Fe powder (325 mesh) according to the above mass ratio, and then ball mill the powders in a ball mill. The ball milling conditions are as follows: ball milling speed of 260 r / min, ball-to-material ratio of 5:1, ball milling time of 15 h, and grinding balls made of zirconia to obtain a mixed powder.

[0030] S2. Prepare a cylindrical graphite mold with an inner diameter of 50 mm. Cover the inner wall of the sleeve and the upper and lower areas that contact the metal powder with graphite paper. Apply a mixture of boron nitride powder and alcohol on the coated graphite paper. Then, place the resulting mixed powder in the graphite mold and apply a certain amount of pressure to the powder using an indenter to ensure that the powder particles are tightly packed and the upper and lower surfaces are flat.

[0031] S3, the graphite mold after pressurization is placed in a spark plasma sintering furnace, and then evacuated to below 10Pa, heated to 1200℃ at a heating rate of 100℃ / min, sintered, and kept warm for 30min. During the heat preservation process, the system sintering pressure is maintained at 35MPa. After the heat preservation is completed, it is cooled to below 100℃, the pressure is released, and the sample is obtained to obtain a ceramic particle reinforced iron-based composite material. The microstructure of the obtained ceramic particle reinforced iron-based composite material is scanned using a scanning electron microscope. The results are shown in FIG. Figure 1 The ceramic particle reinforced iron-based composite material was tested using a Vickers hardness tester and a three-body wear tester. The test results are shown in Table 1.

[0032] Example 2

[0033] A ceramic particle reinforced iron-based composite material comprises the following raw material components, calculated by mass percentage: 10% Cr7C3, 10% TiC, and the balance Fe. The preparation method comprises the following steps:

[0034] S1. Weigh Cr7C3 powder (800 mesh), TiC powder (800 mesh) and Fe powder (240 mesh) according to the above mass ratio, and then ball mill the powders in a ball mill. The ball milling conditions are as follows: ball milling speed of 200 r / min, ball-to-material ratio of 5:1, ball milling time of 12 h, and grinding balls made of zirconia to obtain a mixed powder.

[0035] S2. Prepare a cylindrical graphite mold with an inner diameter of 50 mm. Cover the inner wall of the sleeve and the upper and lower areas that contact the metal powder with graphite paper. Apply a mixture of boron nitride powder and alcohol on the coated graphite paper. Then, place the resulting mixed powder in the graphite mold and apply a certain amount of pressure to the powder using an indenter to ensure that the powder particles are tightly packed and the upper and lower surfaces are flat.

[0036] S3, the graphite mold after pressurization is placed in a spark plasma sintering furnace, and then vacuumed to below 10Pa, heated to 1200℃ at a heating rate of 100℃ / min, sintered, and kept warm for 35min. During the heat preservation process, the system sintering pressure is maintained at 30MPa. After the heat preservation is completed, it is cooled to below 100℃, the pressure is released, and the sample is obtained to obtain a ceramic particle reinforced iron-based composite material. The microstructure of the obtained ceramic particle reinforced iron-based composite material is scanned using a scanning electron microscope. The results are shown in FIG. Figure 2The ceramic particle reinforced iron-based composite material was tested using a Vickers hardness tester and a three-body wear tester. The test results are shown in Table 1.

[0037] Example 3

[0038] A ceramic particle reinforced iron-based composite material comprises the following raw material components, calculated by mass percentage: 20% Cr7C3, 8% TiC, and the balance Fe. The preparation method comprises the following steps:

[0039] S1. Weigh Cr7C3 powder (1340 mesh), TiC powder (1340 mesh) and Fe powder (325 mesh) according to the above mass ratio, and then ball-mill the powders in a ball mill. The ball milling conditions are as follows: ball milling speed of 300 r / min, ball-to-material ratio of 10:1, ball milling time of 12 h, and grinding balls made of zirconia to obtain a mixed powder.

[0040] S2. Prepare a cylindrical graphite mold with an inner diameter of 50 mm. Cover the inner wall of the sleeve and the upper and lower areas that contact the metal powder with graphite paper. Apply a mixture of boron nitride powder and alcohol on the coated graphite paper. Then, place the resulting mixed powder in the graphite mold and apply a certain amount of pressure to the powder using an indenter to ensure that the powder particles are tightly packed and the upper and lower surfaces are flat.

[0041] S3, the graphite mold after pressure was placed in a spark plasma sintering furnace, and then vacuumed to below 10Pa, heated to 1300℃ at a heating rate of 80℃ / min, sintered, and kept warm for 30min. During the heat preservation process, the system sintering pressure was maintained at 30MPa. After the heat preservation was completed, it was cooled to below 100℃, the pressure was released, and the sample was obtained to obtain a ceramic particle reinforced iron-based composite material. The microstructure of the obtained ceramic particle reinforced iron-based composite material was scanned using a scanning electron microscope. The results are shown in FIG. Figure 3 The ceramic particle reinforced iron-based composite material was tested using a Vickers hardness tester and a three-body wear tester. The test results are shown in Table 1.

[0042] Example 4

[0043] A ceramic particle reinforced iron-based composite material comprises the following raw material components, calculated by mass percentage: 15% Cr7C3, 30% TiC, and the balance Fe. The preparation method comprises the following steps:

[0044] S1. Weigh Cr7C3 powder (240 mesh), TiC powder (240 mesh) and Fe powder (1340 mesh) according to the above mass ratio, and then ball-mill the powders in a ball mill. The ball milling conditions are as follows: ball milling speed of 260 r / min, ball-to-material ratio of 1:1, ball milling time of 18 h, and grinding balls made of zirconia to obtain a mixed powder.

[0045] S2. Prepare a cylindrical graphite mold with an inner diameter of 50 mm. Cover the inner wall of the sleeve and the upper and lower areas that contact the metal powder with graphite paper. Apply a mixture of boron nitride powder and alcohol on the coated graphite paper. Then, place the resulting mixed powder in the graphite mold and apply a certain amount of pressure to the powder using an indenter to ensure that the powder particles are tightly packed and the upper and lower surfaces are flat.

[0046] S3, the graphite mold after pressurization is placed in a spark plasma sintering furnace, and then evacuated to below 10Pa, heated to 1100℃ at a heating rate of 100℃ / min, sintered, and kept warm for 40min. During the heat preservation process, the system sintering pressure is maintained at 40MPa. After the heat preservation is completed, it is cooled to below 100℃, the pressure is released, and the sample is obtained to obtain a ceramic particle reinforced iron-based composite material. The microstructure of the obtained ceramic particle reinforced iron-based composite material is scanned using a scanning electron microscope. The results are shown in FIG. Figure 4 The ceramic particle reinforced iron-based composite material was tested using a Vickers hardness tester and a three-body wear tester. The test results are shown in Table 1.

[0047] Comparative Example 1

[0048] The process is basically the same as that of Example 1, except that in step S3, the sintering temperature is 1000°C.

[0049] Finally, a very loose ceramic particle reinforced iron-based composite material sample was obtained. Macroscopic holes were visible inside, the powder was not completely combined together, and there was obvious powder loss during the grinding and polishing process. Therefore, it was impossible to perform experimental measurements such as Vickers hardness and three-body wear performance using a Vickers hardness tester and a three-body wear tester.

[0050] Comparative Example 2

[0051] The process is basically the same as that of Example 1, except that in step S3, the sintering temperature is 1400°C.

[0052] Because the carbon element in the graphite mold and graphite paper infiltrated into the sample during high-temperature sintering, a ceramic particle-reinforced iron-based composite with a higher carbon content was ultimately obtained. This ceramic particle-reinforced iron-based composite was tested using a Vickers hardness tester and a three-body wear tester. The test results are shown in Table 1.

[0053] Comparative Example 3

[0054] The results were essentially the same as those in Example 1, except that in step S3, the system sintering pressure was maintained at 20 MPa during the heat preservation process. The resulting product was a relatively loose ceramic particle-reinforced iron-based composite material. Macroscopic holes were visible within the sample, the powder was not completely bonded together, and powder fell off during the polishing process. Consequently, the ceramic particle-reinforced iron-based composite material could not be tested using a Vickers hardness tester or a three-body wear tester.

[0055] Comparative Example 4

[0056] Substantially the same as Example 1, except that, in step S3, the sintering pressure of the system is maintained at 60MPa during the heat preservation process. Ceramic particles are obtained to reinforce iron-based composite materials, but the material sample is tightly connected to a graphite mold and cannot be effectively demoulded. And there are obvious signs of carburization on the material sample surface, which is very brittle. The core sample cannot meet the three-body wear tester size requirement through cutting, so that it is impossible to carry out three-body wear performance test. However, Vickers hardness test can be carried out using a Vickers hardness tester, and the test results are shown in Table 1.

[0057] Comparative Example 5

[0058] The results were essentially the same as those in Example 1, except that the holding time in step S3 was 10 minutes. The resulting material was a relatively loose ceramic particle-reinforced iron-based composite material. Macroscopic holes were visible within the sample, and the individual powders were not completely bonded together. Powder loss occurred during the polishing process, making it impossible to perform experimental tests on the material, such as Vickers hardness and three-body wear properties, using a Vickers hardness tester or a three-body wear tester. However, Vickers hardness testing was possible using a Vickers hardness tester, as shown in Table 1.

[0059] Comparative Example 6

[0060] Substantially the same as Example 1, except that, in step S3, the holding time is 60 min. Finally, ceramic particles are obtained to reinforce the iron-based composite material, and the material sample is tightly connected to the graphite mold and cannot be effectively demoulded. And there are obvious signs of carburization on the sample surface, which is very brittle. The core sample cannot meet the three-body wear tester size requirements after cutting, so that it is impossible to perform a three-body wear performance test on it, but a Vickers hardness tester can be used to perform Vickers hardness test, and the test results are shown in Table 1.

[0061] Comparative Example 7

[0062] A ceramic particle reinforced iron-based composite material comprises the following raw material components, calculated by mass percentage: 10% Cr7C3, 20% TiC, and the balance Fe. The preparation method comprises the following steps:

[0063] S1. Weigh Cr7C3 powder (325 mesh), TiC powder (325 mesh) and Fe powder (325 mesh) according to the above mass ratio, then ball-mill the powders in a ball mill to obtain a mixed powder, and cold-press to form a green compact;

[0064] S2, place the green body in a vacuum sintering furnace, and then evacuate to 10 -1 Pa, the temperature was raised to 1200°C at a heating rate of 10°C / min, sintered, and held at that temperature for 30 minutes. Afterwards, the material was cooled to below 50°C and sampled to obtain a ceramic particle-reinforced iron-based composite material. The ceramic particle-reinforced iron-based composite material was tested using a Vickers hardness tester and a three-body wear tester. The test results are shown in Table 1.

[0065] Comparative Example 8

[0066] A ceramic particle reinforced iron-based composite material comprises the following raw material components, calculated by mass percentage: 10% Cr7C3, 20% TiC, and the balance Fe. The preparation method comprises the following steps:

[0067] S1. Weigh Cr7C3 powder (325 mesh), TiC powder (325 mesh) and Fe powder (325 mesh) according to the above mass ratio, then ball-mill the powders in a ball mill to obtain a mixed powder, and cold-press the mixed powder into a blank.

[0068] S2, place the green body in a vacuum sintering furnace, and then evacuate to 10 -1 Pa, the temperature was raised to 1500°C at a heating rate of 10°C / min, sintered, and held at that temperature for 60 minutes. After the holding period, the material was cooled to below 50°C and sampled to obtain a ceramic particle-reinforced iron-based composite material. The ceramic particle-reinforced iron-based composite material was tested using a Vickers hardness tester and a three-body wear tester. The test results are shown in Table 1.

[0069] Depend on Figure 1-4 The results show that the ceramic particle reinforced iron-based composite materials obtained in Examples 1-4 all contain carbide Cr7C3 phase, TiC face-centered cubic phase and austenite phase, but do not contain other carbide phases.

[0070] Table 1. Vickers hardness and three-body wear test results of ceramic particle reinforced iron-based composite materials prepared in Examples 1-4 and Comparative Examples 1-8

[0071]

[0072]

[0073] As shown in the results of Table 1, the Vickers hardness HV of the ceramic particle reinforced iron-based composite material obtained in Example 1 is 1359±40, and the wear loss in 150 minutes is 0.31±0.05. In Comparative Example 1, due to the low sintering temperature, the powders cannot be well combined, resulting in obvious defects such as powder particles and holes in the obtained sample, which cannot be used for subsequent detection and analysis. This shows that the sintering temperature of the ceramic particle reinforced iron-based composite material cannot be too low; in Comparative Example 2, due to the high sintering temperature, the C element in the graphite mold and graphite paper penetrates into the sample and the diffusion rate of the C element at high temperature is very high and can enter the core of the sintered sample, thereby significantly increasing the C content of the sample and causing the sample phase to change, resulting in more brittle carbide phases, which leads to a significant decrease in Vickers hardness and wear resistance. The above analysis results show that the sintering temperature when preparing ceramic particle reinforced iron-based composite materials needs to be controlled within a certain temperature range.

[0074] In comparative example 3, because the sintering pressure is too low, some powders will not be well combined into a block, and there are still obvious defects such as powder particles and holes in the sample, which cannot be used for subsequent detection and analysis. This shows that the sintering pressure at a certain sintering temperature when preparing ceramic particles to enhance iron-based composite materials cannot be set too low. In comparative example 4, because the sintering pressure is too high, the graphite mold and the sample will be closely combined together, and the C element in the graphite mold and the graphite paper will penetrate into the sample. The size of the core obtained after removing the carburized layer on the sample surface is relatively small, and Vickers hardness detection can only be carried out, and the Vickers hardness result of the core sample is significantly lower than that of Example 1, which may be attributed to the fact that some C elements still penetrate into the initiator phase and change. The above analysis results show that the sintering pressure for preparing ceramic particles to enhance iron-based composite materials needs to be controlled within a certain numerical range to ensure that a sample with better density and a more ideal size is obtained.

[0075] In comparative example 5, because the heat preservation and pressure holding time is too short, each powder will fail to be well combined into a block, and there are still obvious defects such as powder particles and holes in the sample, so it is impossible to use for subsequent detection and analysis, which shows that the heat preservation and pressure holding time under a certain sintering temperature and sintering pressure can not be set too short when preparing ceramic particles to enhance iron-based composite materials. In comparative example 6, because the heat preservation and pressure holding time is too long, the graphite mold and the sample will be closely combined together, and the C element in the graphite mold and the graphite paper will penetrate into the sample, and the size of the core obtained after the sample surface carburized layer is removed is relatively small, so Vickers hardness test can only be carried out, and the Vickers hardness result of the core sample is significantly worse than that of Example 1, which may be attributed to the fact that some C elements still penetrate into the initiator phase and change. The above analysis results show that the heat preservation and pressure holding time of ceramic particles to enhance iron-based composite materials needs to be controlled within a certain numerical range to ensure that the sample with better density and ideal size is obtained.

[0076] Comparative Examples 7 and 8 used a conventional vacuum sintering furnace to prepare ceramic particle-reinforced iron-based composites. While the sintering temperature and time in Comparative Example 7 were identical to those in Example 1, no pressure was applied during the sintering process, whereas Example 1 maintained a constant pressure of 35 MPa. The sintering results showed that the powders in Comparative Example 7 failed to form a solid mass, and the sample still contained significant defects such as powder particles and pores, making it unusable for subsequent testing and analysis. This suggests that the sintering temperature and time need to be appropriately increased when preparing ceramic particle-reinforced iron-based composites using conventional sintering methods.

[0077] Comparative Example 8 significantly increased the sintering temperature and time compared to Comparative Example 7. The Vickers hardness and wear resistance of Comparative Example 8 were significantly lower than those of Example 1. This was because the ceramic particle-reinforced iron-based composite material produced in Comparative Example 8 still had inevitable defects such as pores and coarse grains due to the excessively high sintering temperature.

[0078] In addition, compared with as-cast high-chromium cast iron, the ceramic particle-reinforced iron-based composite materials prepared in Examples 1 to 4 of the present invention have higher Vickers hardness and better wear resistance. Therefore, they can be used as high-performance iron-based composite materials in mining, metallurgy and drilling projects, and have very broad application prospects.

[0079] The present invention is not limited to the above-mentioned specific implementation methods. Various changes made by ordinary technicians in this field based on the above-mentioned concept without creative work are all within the scope of protection of the present invention.

Claims

1. A ceramic particle reinforced iron-based composite material, characterized in that: Calculated by mass percentage, it includes the following raw material components: Cr7C3 10-20%, TiC 8-30%, and the balance Fe; The method for preparing the ceramic particle reinforced iron-based composite material comprises the following steps: S1. Weigh Cr7C3 powder, TiC powder and Fe powder according to the formula, mix and ball mill to obtain a mixed powder; S2. The obtained mixed powder is placed into a graphite mold and pressed to ensure that the powder particles are tightly packed and the upper and lower surfaces are flat; S3, placing the pressed mold in a spark plasma sintering furnace for sintering to obtain a ceramic particle reinforced iron-based composite material; The specific process of the sintering treatment is: placing the pressurized mold in a spark plasma sintering furnace, evacuating the vacuum to below 10 Pa, raising the temperature to 1100-1300°C at a heating rate of 80-100°C / min for sintering, keeping the temperature for 20-40 minutes, and maintaining the system sintering pressure at 30-40 MPa during the holding process, and then cooling.

2. The ceramic particle reinforced iron-based composite material according to claim 1, characterized in that: The particle size of the Cr7C3 powder is 240 mesh to 1340 mesh, the particle size of the TiC powder is 240 mesh to 1340 mesh, and the particle size of the Fe powder is 240 mesh to 1340 mesh.

3. The ceramic particle reinforced iron-based composite material according to claim 1, characterized in that: In step S1, the ball milling conditions are as follows: a ball milling speed of 200-300 r / min, a ball-to-material ratio of 1-10:1, a ball milling time of 12-18 h, and the grinding ball material is zirconia.

4. The ceramic particle reinforced iron-based composite material according to claim 1, characterized in that: The cooling is to below 100°C.

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