Zirconium carbide / silicon carbide composite material part and additive manufacturing method thereof

Abstract

The invention discloses a zirconium carbide / silicon carbide composite material part and an additive manufacturing method thereof, and belongs to the technical field of SiC ceramic matrix composite material preparation. The method comprises the following steps: preparing mixed powder, adding a resin material as a binder into the mixed powder to prepare a raw material, and then preparing composite powder; designing a three-dimensional CAD model of the target three-dimensional zirconium carbide / silicon carbide composite material part, and forming the composite powder by adopting an additive manufacturing technology to obtain a green body; carrying out heating treatment on the green body to carbonize the resin material to obtain a prefabricated body; and adding silicon into the preform for reactive sintering to obtain the zirconium carbide / silicon carbide composite material part. The composite powder suitable for additive manufacturing and reactive sintering and the ternary reactive sintering technology of zirconium disilicide, carbon and silicon are researched and developed, the difficult problem of forming of zirconium carbide / silicon carbide composite material complex parts is solved, the sintering process requirement is lowered, deformation and cracking are prevented, and the blank of additive manufacturing in the field is filled.

Description

Technical Field

[0001] The invention belongs to the technical field of preparation of SiC ceramic-based composite materials, and in particular relates to a zirconium carbide / silicon carbide composite material part and an additive manufacturing method thereof. Background Art

[0002] Zirconium carbide / silicon carbide composites combine the advantages of both materials to form a new type of ceramic matrix composite with better performance. This type of composite material is designed to improve the material's high temperature stability, mechanical strength (especially fracture toughness), wear resistance and oxidation resistance, and is suitable for applications in extreme environments, such as aerospace, nuclear energy, high-temperature gas turbines and other fields.

[0003] However, in order to obtain dense zirconium carbide-silicon carbide composite ceramics, it is usually necessary to apply higher sintering temperatures and sintering pressures. In other words, the densification process of this composite ceramic often relies on promoting close contact and mutual diffusion between material particles by applying significant pressure under high temperature conditions, thereby achieving the densification of the sintered body. Such a high temperature and high pressure environment helps to accelerate the migration rate of atoms or molecules inside the material, allowing zirconium carbide and silicon carbide particles to combine more effectively to form a composite ceramic material with high strength and high density.

[0004] Additive Manufacturing (AM), commonly known as 3D printing, is a manufacturing process that builds physical objects by continuously adding material layers (such as powder, liquid or sheet materials) based on computer-generated three-dimensional design data, making it possible to design and prepare complex structural materials. Additive manufacturing technology can be used for the processing and manufacturing of ceramics, polymer materials, metals and various composite models and parts. Although additive manufacturing technology has shown great potential in the preparation of composite materials, existing manufacturing methods have not directly solved the problem of how to use additive manufacturing technology to form and prepare dense zirconium carbide / silicon carbide composite parts.

[0005] At present, the Chinese invention patent with the publication number CN107540376A introduces a zirconium carbide-silicon carbide composite ceramic material and its preparation method. This method significantly simplifies the process conditions through the spark plasma sintering technology, reduces the sintering temperature and pressure requirements, and enables the ceramic material to achieve densification at a relatively low temperature and in a short time, while obtaining a high-quality ceramic block with fine grains and uniform composition. However, although this method has improved the sintering efficiency, it still relies on a higher sintering temperature range (1650-1900℃) and certain pressure conditions (20-40MPa) to ensure the density of the material.

[0006] Based on this, the inventors considered combining it with additive manufacturing technology and found that if they tried to combine this material with additive manufacturing technology, they would face two major challenges: first, the physical and chemical properties of existing materials may not be fully compatible with the fine processing requirements of additive manufacturing; second, the complex structural parts formed by additive manufacturing may be difficult to densify evenly due to their complex structure when subsequently densified using spark plasma sintering technology or traditional pressureless sintering methods, and may even cause deformation and cracking problems.

[0007] In summary, when applying zirconium carbide-silicon carbide composite ceramic materials to the field of additive manufacturing, current technology not only faces the problem of material adaptability, but also faces the problem that the sintering process is difficult to ensure the density of the material under complex structures and is prone to defects. Therefore, it is necessary to further explore new material modification methods and sintering technologies to overcome these challenges and promote the widespread application of zirconium carbide-silicon carbide composite ceramics in the field of additive manufacturing. Summary of the invention

[0008] In order to overcome the shortcomings of the above-mentioned prior art, the purpose of the present invention is to provide a zirconium carbide / silicon carbide composite material part and an additive manufacturing method thereof, prepare a composite powder suitable for both additive manufacturing and reaction sintering processes, and solve the problem of forming complex parts of zirconium carbide / silicon carbide composite materials; develop three reaction sintering technologies of zirconium disilicide, carbon and silicon, and solve the technical problems in the prior art that the sintering process of dense zirconium carbide ceramics has high requirements, easy deformation and cracking, filling the technical blank of additive manufacturing of zirconium carbide / silicon carbide composite materials.

[0009] In order to achieve the above object, the present invention adopts the following technical solutions:

[0010] The present invention provides an additive manufacturing method for zirconium carbide / silicon carbide composite material parts, comprising the following steps:

[0011] S1: preparing a mixed powder, adding a resin material as a binder to obtain a raw material, and then preparing a composite powder; wherein the mixed powder is a mixture of zirconium disilicide and graphite; or, the mixed powder is a mixture of zirconium disilicide, silicon carbide and graphite;

[0012] S2: Design a 3D CAD model of the target 3D zirconium carbide / silicon carbide composite part, and shape the composite powder using additive manufacturing technology to obtain a green body;

[0013] S3: heating the green body to carbonize the resin material to obtain a preform;

[0014] S4: adding silicon to the preform for reaction sintering, so that zirconium disilicide and carbon (provided by graphite) in the preform react with silicon to generate zirconium carbide / silicon carbide, and obtaining a zirconium carbide / silicon carbide composite material part.

[0015] In one embodiment, in S1, the mass ratio of zirconium disilicide to graphite is 1-10:1-10.

[0016] In one embodiment, in S1, the mass ratio of zirconium disilicide, silicon carbide, and graphite is 1-10:0-3:1-10.

[0017] In one embodiment, in S1, the raw material further comprises a flow aid; the flow aid is carbon black; and the amount of the flow aid added is 0 to 1 wt % of the mass of the mixed powder.

[0018] In one embodiment, in S1, the resin material is one or more of nylon 6, nylon 12, epoxy resin, phenolic resin, stearic acid and polyetheretherketone; the added amount of the resin material is 1 to 20 wt% of the mass of the mixed powder.

[0019] In one embodiment, in S1, the method for preparing the composite powder is a solvent precipitation method, a thermal coating method or a spray granulation method.

[0020] In one embodiment, in S2, the additive manufacturing technology is any one of laser selective sintering, three-dimensional printing, photocuring, laser selective melting, and molten deposition.

[0021] In one embodiment, in S3, the heating process is as follows:

[0022] In a protective atmosphere or vacuum environment, heat at 500℃-600℃ for 2h-10h;

[0023] The protective atmosphere is argon or nitrogen.

[0024] In one embodiment, in S4, the amount of silicon added is 20-60 wt% of the mass of the preform; in S4, the temperature of the reaction sintering is 1500°C-1900°C.

[0025] The present invention provides a zirconium carbide / silicon carbide composite material part produced by the additive manufacturing method of the zirconium carbide / silicon carbide composite material part.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] The present invention provides an additive manufacturing method for zirconium carbide / silicon carbide composite material parts. The method firstly selects zirconium disilicide and graphite as raw materials and adds a resin material as a binder to prepare a composite powder with good fluidity and processability. This raw material combination not only takes into account the chemical compatibility and reactivity of the materials, but also makes full use of the bonding properties of the resin material, so that the mixed powder can better maintain the shape and stability during the additive manufacturing process, thereby solving the problem of material adaptability. Secondly, the additive manufacturing technology is used to directly print out a blank with a complex part structure according to a three-dimensional CAD model. This technical method greatly improves the degree of freedom of design and the flexibility of manufacturing, making it possible to make zirconium carbide / silicon carbide composite material parts with complex structures. Then, after the blank is heated to carbonize the resin material, silicon is added to the preform for reaction sintering. In this process, zirconium disilicide, carbon and silicon react chemically to generate zirconium carbide and silicon carbide. This in-situ reaction sintering method not only simplifies the process flow, but also ensures the uniformity and density of the material. More importantly, it does not require external application of high pressure, and the volume change of the material during the sintering process is small, which effectively reduces the deformation and cracking problems common in traditional sintering processes. In summary, the above manufacturing method can produce three-dimensional zirconium carbide / silicon carbide composite parts with complex geometric shapes and internal structures, meeting the needs of complex structural parts. The material is densified through the reaction sintering process, without the need for external application of high pressure, and the volume change of the material during the sintering process is small, which effectively reduces the deformation and cracking problems in traditional sintering processes, thereby improving the density of the material and reducing the defect rate.

[0028] Furthermore, the additive manufacturing method has many advantages. First, the shape and size of the molding structure can be easily changed, with precise control and flexible operation. Second, no expensive molds are required during the molding process, which can greatly shorten the production cycle, improve efficiency and reduce production costs. Third, raw materials are saved and the materials used are non-toxic and pollution-free.

[0029] Furthermore, the above preparation method can reduce the difficulty of ZrC sintering. The traditional ZrC sintering process may face challenges such as high melting point and low diffusion coefficient, resulting in high sintering difficulty and high cost. In the present invention, Si2Zr is used as one of the raw materials, and ZrC and SiC are directly generated by reaction sintering and densification is achieved, which effectively reduces the sintering difficulty of ZrC. This is because the reaction of Si2Zr with carbon and silicon can be carried out at a relatively low temperature, and the reaction rate is fast, thereby simplifying the sintering process and improving production efficiency. The present invention can directly manufacture zirconium carbide / silicon carbide composite parts with complex geometric shapes with the help of additive manufacturing technology. This technology does not require traditional molds or processing equipment, can greatly shorten the product development cycle, and reduce production costs. At the same time, additive manufacturing technology can also achieve precise control and optimized layout of materials, further improving the performance and reliability of parts. In addition, during the reaction sintering process, the three reactions of Si2Zr, carbon and silicon can generate SiC and ZrC. These two compounds can be intertwined and tightly combined during the sintering process to form a high-density composite material. In addition, since the volume change of the material during reaction sintering is small (i.e., small shrinkage), the deformation and cracking problems common in traditional pressureless sintering can be effectively reduced. This helps to improve the overall performance and stability of the composite material. Zirconium carbide / silicon carbide composites have excellent mechanical properties, thermal stability and corrosion resistance. Composite materials prepared by reaction sintering can maintain these excellent properties and further improve them in some aspects. For example, high density and low porosity help to improve the strength and hardness of the material; while the synergistic effect of SiC and ZrC can improve the thermal conductivity and thermal shock resistance of the material. Moreover, compared with some traditional sintering methods, the reaction sintering process may be more environmentally friendly and sustainable. Because it reduces the dependence on high-temperature furnaces and large amounts of energy, it reduces energy consumption and carbon emissions. At the same time, by precisely controlling the reaction conditions and the ratio of raw materials, the generation of waste and the emission of harmful substances can also be reduced. In summary, this method of using Si2Zr, carbon and silicon for reaction sintering to generate zirconium carbide / silicon carbide composite materials has shown significant advantages in reducing sintering difficulty, directly forming complex structural parts, improving material density and performance, and environmental sustainability.

[0030] Furthermore, the use of resin in the preparation of zirconium carbide / silicon carbide composites has many significant benefits. These benefits are mainly reflected in enhancing the bonding force of materials, improving formability, improving structural strength, enhancing density, and optimizing the performance of the final product. As an important adhesive, resin can significantly enhance the bonding force between materials. In the preparation of zirconium carbide / silicon carbide composites, resin binders can firmly bond different particles or components together to form a tight bonding interface. This enhanced bonding force helps to reduce defects and pores inside the material and improve the overall performance of the material. Resin binders play a vital role in the additive manufacturing process. It can bond powder particles into a green body with a certain strength and shape, thereby improving the formability of the material. The use of resin binders can make the green body more stable during the manufacturing process, reduce the occurrence of problems such as cracking and deformation, and ensure the dimensional accuracy and shape complexity of the final product. Resin carbonization treatment is an important link in the preparation of composite materials with resin binders. In this process, the resin gradually decomposes and converts into carbonaceous residues, which can continue to provide structural support for the green body. Therefore, the use of resin and carbonization treatment can significantly improve the structural strength of the composite material. In addition, the resin can also improve the mechanical properties of the material, such as increasing hardness and tensile strength, further improving the overall performance of the composite material. The use of resin and carbonization treatment can also help improve the density of the composite material. During the reaction sintering process, zirconium disilicide, carbon and added silicon react to form zirconium carbide / silicon carbide composite materials. If there are a large number of pores or incompletely reacted residues inside the blank, the density of the composite material will be seriously affected. The resin binder can fill the tiny pores and defects inside the material and reduce the porosity; at the same time, the carbonaceous residues produced during the resin carbonization process can further compact the material structure, thereby improving the density of the composite material. In summary, the use of resin binders and carbonization treatment can significantly improve the various properties of zirconium carbide / silicon carbide composite materials. These properties include key indicators such as mechanical strength, wear resistance, and corrosion resistance. The optimized composite material will be more suitable for application requirements in extreme environments such as high temperature, high pressure, and corrosion resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 A flow chart of an additive manufacturing method for a zirconium carbide / silicon carbide composite material part provided in one embodiment of the present invention. DETAILED DESCRIPTION

[0032] In order to enable those skilled in the art to understand the characteristics and effects of the present invention, the following is a general description and definition of the terms and expressions mentioned in the specification and claims. Unless otherwise specified, all technical and scientific terms used in the text are the common meanings understood by those skilled in the art for the present invention. In the event of a conflict, the definition in this specification shall prevail.

[0033] The theories or mechanisms described and disclosed herein, whether correct or incorrect, should not limit the scope of the present invention in any way, that is, the present invention can be implemented without being limited by any specific theory or mechanism.

[0034] Herein, all features such as values, quantities, contents and concentrations defined in the form of numerical ranges or percentage ranges are for simplicity and convenience only. Accordingly, the description of numerical ranges or percentage ranges should be considered to have included and specifically disclosed all possible secondary ranges and individual values ​​within the range (including integers and fractions).

[0035] In this document, unless otherwise specified, “includes,” “including,” “contains,” “has,” or similar terms cover the meanings of “consisting of” and “mainly consisting of,” for example, “A includes a” covers the meanings of “A includes a and other” and “A only includes a.”

[0036] In this document, in order to make the description concise, not all possible combinations of various technical features in various embodiments or examples are described. Therefore, as long as there is no contradiction in the combination of these technical features, the various technical features in various embodiments or examples can be combined arbitrarily, and all possible combinations should be considered to be within the scope of this specification.

[0037] The present invention provides a zirconium carbide / silicon carbide composite material part and an additive manufacturing method thereof. The additive manufacturing method comprises selecting zirconium disilicide (Si2Zr) of a certain particle size, silicon carbide, graphite, a flow aid (carbon black) and a resin material, preparing a composite powder for additive manufacturing by a solvent precipitation, heat coating or spray granulation method, and then forming a blank by an additive manufacturing technology. The prepared blank is finally prepared into a three-dimensional structure ZrC / SiC composite material part through carbonization and reaction sintering.

[0038] like Figure 1 As shown, in one embodiment, a method for additive manufacturing of a zirconium carbide / silicon carbide composite material part is provided, comprising the following steps:

[0039] S1: zirconium disilicide and graphite (carbon source) are mixed to obtain a mixed powder, a resin material is added as a binder to obtain a raw material, and then a composite powder is prepared;

[0040] S2: Design a 3D CAD model of the target 3D zirconium carbide / silicon carbide composite part, and shape the composite powder using additive manufacturing technology to obtain a green body;

[0041] S3: heating the green body to carbonize the resin material to obtain a preform;

[0042] S4: adding silicon to the preform for reaction sintering, so that the zirconium disilicide, carbon and silicon in the preform react to generate zirconium carbide / silicon carbide, and obtain a zirconium carbide / silicon carbide composite material part.

[0043] In addition, the particle size of the zirconium disilicide is 1 to 100 μm, which can meet the powder fluidity requirements for powder spreading in additive manufacturing technology and is conducive to reaction sintering densification.

[0044] The present invention adopts additive manufacturing technology to form and prepare ZrC / SiC composite materials, and can design and manufacture complex three-dimensional ZrC / SiC composite parts according to the actual use requirements of the materials. The preparation process is simple and easy, and the prepared ZrC / SiC composite materials have the advantages of uniform components, high fracture toughness, and good high-temperature stability. The reaction sintering method in the above-mentioned manufacturing method generates zirconium carbide and silicon carbide by the reaction of zirconium disilicide and carbon, and generates silicon carbide by the reaction of silicon and carbon. The reaction sintering process is simple, and the composition and structure of the zirconium carbide / silicon carbide composite material finally prepared can be effectively regulated by the composition of the raw materials, and the three-phase reaction sintering process of zirconium disilicide, carbon and silicon used in the present invention is simpler and easier than the traditional sintering process.

[0045] In a specific implementation process, in S1, the mass ratio of zirconium disilicide to graphite is 1-10:1-10. The resin material is one or more of nylon 6, nylon 12, epoxy resin, phenolic resin, stearic acid and polyetheretherketone; the amount of the resin material added is 1-20wt% of the mass of the mixed powder. The method for preparing the composite powder is solvent precipitation method, thermal coating method or spray granulation method.

[0046] In the specific implementation process, in S2, the additive manufacturing technology is any one of laser selective sintering, three-dimensional printing, photocuring, laser selective melting, and molten deposition.

[0047] In the specific implementation process, in S3, the heating process is as follows:

[0048] In a protective atmosphere (argon, nitrogen) or vacuum environment, heat at 500°C-600°C for 2h-10h.

[0049] In a specific implementation process, in S4, the silicon is silicon particles, and the amount of silicon added is 20-60 wt % of the mass of the preform. The reaction sintering is performed at a temperature of 1500°C to 1900°C.

[0050] In one embodiment, a method for additive manufacturing of a zirconium carbide / silicon carbide composite material part is provided, which specifically comprises the following steps:

[0051] (1) Weigh a certain proportion of zirconium disilicide, silicon carbide and graphite powder, use a ball mill mixing device to fully mix the above powders to obtain a mixed powder, add no more than 1wt% of carbon black as a flow aid to the mixed powder, select a suitable resin material as needed, add the resin material at 1 to 20wt% of the mass of the mixed powder, and mix again to obtain a composite powder suitable for additive manufacturing by solvent precipitation, thermal coating or spray granulation.

[0052] In step (1), the particle sizes of zirconium disilicide, silicon carbide and graphite are 1 to 100 μm, and the mass fraction ratio of zirconium disilicide, silicon carbide and graphite is 1 to 10:0 to 3:1 to 10.

[0053] The resin material in step (1) is one or more of nylon 6, nylon 12, epoxy resin, phenolic resin, stearic acid and polyetheretherketone.

[0054] (2) Using 3D modeling software to design the required CAD model of the zirconium carbide / silicon carbide composite material part, setting the printer parameters including layer thickness, scanning speed, etc. according to the selected additive manufacturing technology, and using the composite powder prepared in step (1) to print out the blank using the selected additive manufacturing technology.

[0055] The additive manufacturing technology in step (2) is one of laser selective sintering, three-dimensional printing, photocuring, laser selective melting, and molten deposition.

[0056] (3) The green body obtained in step (2) is placed in a protective atmosphere (such as argon or nitrogen) or a vacuum environment, and heated at a temperature range of 500° C. to 600° C. for 2 h to 10 h to completely carbonize the resin material.

[0057] (4) Add 20 to 60 wt % of silicon, in the form of silicon particles, to the preform obtained in step (3), place the preform with silicon in a reaction sintering furnace, and perform reaction sintering at a high temperature of 1500° C. to 1900° C. until zirconium disilicide, carbon and silicon are completely reacted to form a zirconium carbide / silicon carbide composite material, and take out the final zirconium carbide / silicon carbide composite material part after naturally cooling to room temperature.

[0058] On the other hand, the present invention provides a zirconium carbide / silicon carbide composite material produced by the above-mentioned additive manufacturing method.

[0059] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall within the scope limited by the appended claims of the application equally.

[0060] The following examples use conventional instruments and equipment in the art. The experimental methods in the following examples where specific conditions are not specified are usually carried out under conventional conditions or under conditions recommended by the manufacturer. The various raw materials used in the following examples are conventional commercial products unless otherwise specified, and their specifications are conventional specifications in the art. In the specification of the present invention and the following examples, unless otherwise specified, "%" means weight percentage, "part" means weight part, and ratio means weight ratio.

[0061] Example 1

[0062] Weigh 1 part of zirconium disilicide powder with a particle size of 1 μm and 1 part of graphite powder with a particle size of 1 μm, use a ball mill mixing equipment to fully mix the above powders, add 0.1wt% of carbon black as a flow aid to the mixed powder, add 10wt% nylon 6 based on the mass of the mixed powder, and mix again, disperse the selected mixed powder in an alcohol solvent, and then place it in a reactor, heat the reactor to 180°C, keep it warm for 2 hours, then naturally cool it to room temperature, take out the sample, filter it, and dry it at 80°C for 10 hours to obtain powder for additive manufacturing.

[0063] The prepared powder for additive manufacturing was sintered by laser selective sintering equipment, and the sintering parameters were as follows: the powder layer thickness was 150 μm, the laser power was 20 W, the scanning speed was 1500 mm / s, and the scanning spacing was 100 μm. After sintering, the green body was carbonized at 500 ° C in an argon atmosphere for 2 hours to obtain a carbon preform.

[0064] The prepared carbon preform is placed in a reaction sintering furnace, 60wt% of silicon in the preform is added, the temperature is raised to 1500°C in a vacuum atmosphere, and the reaction sintering is completed by keeping the temperature for 2 hours to obtain the required zirconium carbide / silicon carbide composite material parts.

[0065] Example 2

[0066] Weigh 5 parts of zirconium disilicide powder with a particle size of 10 μm, 1 part of silicon carbide powder with a particle size of 40 μm, and 1 part of graphite powder with a particle size of 1 μm, use a ball mill mixing equipment to fully mix the above powders, add 0.1 wt% of carbon black as a flow aid to the mixed powder, add 13 wt% of epoxy resin based on the mass of the mixed powder, and mix again to obtain powder for additive manufacturing.

[0067] The prepared powder for additive manufacturing was sintered by laser selective sintering equipment, and the sintering parameters were as follows: the powder layer thickness was 150 μm, the laser power was 20 W, the scanning speed was 1500 mm / s, and the scanning spacing was 100 μm. After sintering, the green body was carbonized at 600 ° C in an argon atmosphere for 2 hours to obtain a carbon preform.

[0068] The prepared carbon preform is placed in a reaction sintering furnace, 20wt% of silicon of the preform is added, the temperature is raised to 1650°C in a vacuum atmosphere, and the reaction sintering is completed by keeping the temperature for 2 hours to obtain the required zirconium carbide / silicon carbide composite material parts.

[0069] Example 3

[0070] Weigh 10 parts of zirconium disilicide powder with a particle size of 100 μm, 3 parts of silicon carbide powder with a particle size of 50 μm, and 10 parts of graphite powder with a particle size of 1 μm, use a ball mill mixing equipment to fully mix the above powders, add 1 wt% of carbon black as a flow aid to the mixed powder, add 20 wt% of nylon 12 based on the mass of the mixed powder, and mix again, disperse the selected mixed powder in an alcohol solvent, and then place it in a reactor, heat the reactor to 190°C, keep it warm for 2 hours, then naturally cool it to room temperature, take out the sample, filter it, and dry it at 80°C for 10 hours to obtain powder for additive manufacturing.

[0071] The prepared powder for additive manufacturing was sintered by laser selective sintering equipment, and the sintering parameters were as follows: the powder layer thickness was 150 μm, the laser power was 20 W, the scanning speed was 1500 mm / s, and the scanning spacing was 100 μm. After sintering, the green body was carbonized at 500 ° C in an argon atmosphere for 2 hours to obtain a carbon preform.

[0072] The prepared carbon preform is placed in a reaction sintering furnace, 30wt% of silicon of the preform is added, the temperature is raised to 1900°C in a vacuum atmosphere, and the reaction sintering is completed by keeping the temperature for 2 hours to obtain the required zirconium carbide / silicon carbide composite material parts.

[0073] Example 4

[0074] Weigh 5 parts of zirconium disilicide powder with a particle size of 10 μm, 1 part of silicon carbide powder with a particle size of 50 μm, and 1 part of graphite powder with a particle size of 1 μm, use a ball mill mixing equipment to fully mix the above powders, add 0.1 wt% of carbon black as a flow aid to the mixed powder, add 10 wt% of polyetheretherketone based on the mass of the mixed powder, and mix again, disperse the selected mixed powder in an alcohol solvent, and then place it in a reactor, heat the reactor to 260°C, keep it warm for 2 hours, then naturally cool it to room temperature, take out the sample, filter it, and dry it at 80°C for 10 hours to obtain powder for additive manufacturing.

[0075] The obtained powder for additive manufacturing was sintered by a three-dimensional printing device, and the sintering parameters were as follows: the powder layer thickness was 150 μm, the laser power was 20 W, the scanning speed was 1500 mm / S, the scanning spacing was 100 μm, and the preheating temperature was 120 ° C. After sintering, the green body was carbonized at 600 ° C in a nitrogen atmosphere for 2 hours to obtain a carbon preform.

[0076] The prepared carbon preform is placed in a reaction sintering furnace, 30wt% of silicon in the preform is added, the temperature is raised to 1650°C in a vacuum atmosphere, and the reaction sintering is completed by keeping the temperature for 2 hours to obtain the required zirconium carbide / silicon carbide composite material parts.

[0077] Example 5

[0078] Weigh 5 parts of zirconium disilicide powder with a particle size of 10 μm, 1 part of silicon carbide powder with a particle size of 50 μm, and 1 part of graphite powder with a particle size of 1 μm, use a ball mill mixing equipment to fully mix the above powders, add 0.1 wt% of carbon black as a flow aid to the mixed powder, add 3 wt% of phenolic resin based on the mass of the mixed powder, and mix again, use a hot coating method to heat the mixed powder to 120°C, stir and add a curing agent to obtain a powder for additive manufacturing.

[0079] The obtained powder for additive manufacturing was sintered by a three-dimensional printing device, and the sintering parameters were as follows: the powder layer thickness was 150 μm, the laser power was 20 W, the scanning speed was 1500 mm / S, the scanning spacing was 100 μm, and the preheating temperature was 120 ° C. After sintering, the green body was carbonized at 600 ° C in a nitrogen atmosphere for 2 hours to obtain a carbon preform.

[0080] The prepared carbon preform is placed in a reaction sintering furnace, 30wt% of silicon in the preform is added, the temperature is raised to 1650°C in a vacuum atmosphere, and the reaction sintering is completed by keeping the temperature for 2 hours to obtain the required zirconium carbide / silicon carbide composite material parts.

[0081] Example 6

[0082] Weigh 5 parts of zirconium disilicide powder with a particle size of 1 μm, 1 part of silicon carbide powder with a particle size of 1 μm, and 1 part of graphite powder with a particle size of 1 μm, use a ball mill mixing device to fully mix the above powders, add 1wt% stearic acid based on the mass of the mixed powders, dissolve it in alcohol, and disperse it evenly. Use a spray granulation method to prepare granulated powder, and granulate the granulated powder.

[0083] And mix evenly again, use the hot coating method to heat the selected mixed powder to 120℃, stir and add the curing agent to obtain the powder for additive manufacturing. Mix with epoxy resin photosensitive resin at a mass fraction of 15%, and use the ball milling method to prepare a slurry suitable for photocuring additive manufacturing technology. Add it to the ball milling jar for ball milling at a mass ratio of 5:10 (raw material: ZrO2 grinding ball). The ball milling process is completed on a planetary ball mill, with a ball milling speed of V=500r / min and a ball milling time of t=4h. After the ball milling is completed, the slurry for additive manufacturing is taken out.

[0084] The prepared slurry for additive manufacturing was cured and formed using a light curing device, with the parameters of laser wavelength 405nm, power 150mW, single layer thickness 100μm, scanning rate 1000mm / S, and scanning spacing 0.2mm. After forming, the green body was carbonized at 600℃ in a nitrogen atmosphere for 2h to obtain a carbon preform.

[0085] The prepared carbon preform is placed in a reaction sintering furnace, 30wt% of silicon in the preform is added, the temperature is raised to 1650°C in a vacuum atmosphere, and the reaction sintering is completed by keeping the temperature for 2 hours to obtain the required zirconium carbide / silicon carbide composite material parts.

[0086] The present invention adopts additive manufacturing technology to form and prepare additively manufactured zirconium carbide / silicon carbide composite material parts, solves the forming and sintering technical problems in the forming and preparation process of three-dimensional additively manufactured zirconium carbide / silicon carbide composite material parts, and can quickly prepare three-dimensional additively manufactured zirconium carbide / silicon carbide composite materials with complex structures according to the CAD model of the design requirements. The prepared three-dimensional additively manufactured zirconium carbide / silicon carbide composite material has high molding accuracy and can form complex structures. At the same time, the technology has the advantages of very high design freedom and is easy to operate. More importantly, the above-mentioned manufacturing method generates silicon carbide and zirconium carbide and realizes densification through the three-phase reaction of zirconium disilicide, carbon and silicon, and no high pressure is applied externally. A high-density zirconium carbide / silicon carbide composite material can be obtained, and the volume change of the material during the sintering process is small (i.e., small shrinkage), which effectively reduces the deformation and cracking problems in traditional pressureless sintering.

[0087] In summary, the present invention provides a zirconium carbide / silicon carbide composite material part and an additive manufacturing method thereof, develops a composite powder suitable for additive manufacturing and reaction sintering, and a ternary reaction sintering technology of zirconium disilicide, carbon and silicon, solves the molding problem of complex parts of zirconium carbide / silicon carbide composite materials, reduces the sintering process requirements, prevents deformation and cracking, and fills the gap in additive manufacturing in this field.

[0088] The above contents are only for explaining the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A method for additive manufacturing of zirconium carbide / silicon carbide composite parts, characterized in that: The following steps are involved: S1: preparing a mixed powder, adding a resin material as a binder to obtain a raw material, and then preparing a composite powder; wherein the mixed powder is a mixture of zirconium disilicide and graphite; or, the mixed powder is a mixture of zirconium disilicide, silicon carbide and graphite; S2: Design a 3D CAD model of the target 3D zirconium carbide / silicon carbide composite part, and shape the composite powder using additive manufacturing technology to obtain a green body; S3: heating the green body to carbonize the resin material to obtain a preform; S4: adding silicon to the preform for reaction sintering, so that the zirconium disilicide, carbon and silicon in the preform react to generate zirconium carbide / silicon carbide, and obtain a zirconium carbide / silicon carbide composite material part.

2. The additive manufacturing method of zirconium carbide / silicon carbide composite material parts according to claim 1, characterized in that: In S1, the mass ratio of zirconium disilicide to graphite is 1-10:1-10.

3. The additive manufacturing method of zirconium carbide / silicon carbide composite material parts according to claim 1, characterized in that: In S1, the mass ratio of zirconium disilicide, silicon carbide and graphite is 1-10:0-3:1-10.

4. The additive manufacturing method of zirconium carbide / silicon carbide composite material parts according to claim 1, characterized in that: In S1, the raw materials further include a flow aid; the flow aid is carbon black; and the amount of the flow aid added is 0 to 1 wt % of the mass of the mixed powder.

5. The additive manufacturing method of zirconium carbide / silicon carbide composite material parts according to claim 1, characterized in that: In S1, the resin material is one or more of nylon 6, nylon 12, epoxy resin, phenolic resin, stearic acid and polyetheretherketone; the added amount of the resin material is 1 to 20wt% of the mass of the mixed powder.

6. The additive manufacturing method of zirconium carbide / silicon carbide composite material parts according to claim 1, characterized in that: In S1, the method for preparing the composite powder is a solvent precipitation method, a thermal coating method or a spray granulation method.

7. The additive manufacturing method of zirconium carbide / silicon carbide composite parts according to claim 1, characterized in that: In S2, the additive manufacturing technology is any one of laser selective sintering, three-dimensional printing, photocuring, laser selective melting, and molten deposition.

8. The additive manufacturing method of zirconium carbide / silicon carbide composite material parts according to claim 1, characterized in that: In S3, the heating process is as follows: In a protective atmosphere or vacuum environment, heat at 500℃-600℃ for 2h-10h; The protective atmosphere is argon or nitrogen.

9. The additive manufacturing method of zirconium carbide / silicon carbide composite material parts according to claim 1, characterized in that: In the S4, the amount of silicon added is 20-60wt% of the mass of the preform; in the S4, the temperature of the reaction sintering is 1500°C-1900°C.

10. A zirconium carbide / silicon carbide composite material part manufactured by the additive manufacturing method for a zirconium carbide / silicon carbide composite material part according to any one of claims 1 to 9.

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