Cold spraying additive manufacturing method for near-zero expansion metal-based composite material

Abstract

The invention discloses a cold spraying additive manufacturing method for a near-zero expansion metal-based composite material, and belongs to the technical field of metal-based composite materials. The method comprises the following steps: selecting raw materials for preparing the negative expansion material, and performing high-temperature solid-phase sintering on the selected raw materials to prepare the negative expansion material; uniformly mixing the prepared negative expansion material with metal powder by adopting a ball milling process to obtain mixed powder; the mixed powder is subjected to spray forming through cold spray additive manufacturing, and the near-zero-expansion metal-based composite material is obtained; and the obtained near-zero expansion metal-based composite material is subjected to heat treatment, so that the mechanical property of the composite material is improved. The method solves the problems that when a traditional method is used for preparing the near-zero-expansion metal-based composite material, due to the fact that the traditional method often relates to a high-temperature process, many materials are sensitive to temperature change, and oxidation, phase change or grain coarsening and the like of the materials are possibly caused.

Description

Technical Field

[0001] The present invention belongs to the technical field of metal matrix composite materials, and in particular relates to a cold spraying additive manufacturing method for a near-zero expansion metal matrix composite material. Background Art

[0002] In the context of the rapid development of key industries such as aerospace, communication information and precision instruments, higher requirements are placed on the dimensional stability of materials under extreme temperature changes to ensure that these components and structures can maintain high precision, high reliability and good service performance. For example, in the aerospace field, materials may experience a temperature difference of up to 200°C in areas close to the sun and far from the sun, which can cause significant internal stress at the material joints (such as pins, keys, holes) due to mismatched thermal expansion coefficients, which may in turn cause microcracks, shorten service life, and even destroy the overall structure. In the field of communications, especially optical communication systems, they are extremely sensitive to temperature changes, and it is necessary to ensure that the optical path can be accurately focused when the temperature difference changes. As part of the optical system, high-performance fiber gyroscopes are very sensitive to temperature changes and need to have low environmental sensitivity and high stability. However, under temperature changes, the fiber loop may be squeezed due to thermal mismatch stress, resulting in reduced accuracy. In the field of electronic packaging and microelectronics, the function and shape accuracy of components and stress changes are closely related. High heat generation causes significant changes in the temperature difference of the application environment, and the mismatch in thermal expansion coefficients between components and packaging materials may produce huge thermal mismatch forces, seriously affecting the size and function of components and leading to failure.

[0003] In summary, the structural changes and functional failures caused by thermal expansion and contraction are becoming increasingly prominent in the fields of aerospace, communication information and microelectronics, limiting the development of these industries. Therefore, the development of materials with excellent dimensional stability and low thermal expansion coefficient is crucial to improving the technical level and reliability of these key industries. Based on this prior art, it is proposed to mix negative expansion materials as thermal expansion inhibitors with positive thermal expansion materials (such as resins, ceramics, metals, etc.) to form composite materials. Adding negative expansion materials to positive thermal expansion materials can make the materials have low or even near-zero thermal expansion characteristics, thereby keeping the thermal expansion coefficient of the composite material stable when the external temperature changes, greatly reducing the residual stress problems caused by thermal expansion and contraction of materials and parts. However, the conventional preparation methods currently used often involve high-temperature treatment during the material preparation process, which may cause problems such as oxidation, phase change or grain coarsening of the material, thereby affecting the performance of the material. In addition, the conventional preparation method may require more post-processing steps to improve the microstructure and mechanical properties of the material. Summary of the invention

[0004] Technical issues to be solved:

[0005] In order to avoid the shortcomings of the prior art, the present invention provides a cold spray additive manufacturing method for a near-zero expansion metal-based composite material. The cold spray additive manufacturing method is used to prepare a near-zero expansion metal-based composite material. During the cold spray molding process, the temperature is kept below the melting point of the material, which helps to reduce problems such as oxidation, phase change or grain coarsening.

[0006] At the same time, the cold spray additive manufacturing method can directly obtain better material properties by optimizing process parameters when preparing near-zero expansion metal-based composite materials, and has the advantages of shorter R&D cycle, lower cost, wider material applicability, higher processing efficiency and better material properties. The present invention solves the problem that when using traditional methods to prepare near-zero expansion metal-based composite materials, because it often involves high-temperature processes, many materials are sensitive to temperature changes, which may cause oxidation, phase change or grain coarsening of the material.

[0007] The technical solution of the present invention is: a cold spray additive manufacturing method for near-zero expansion metal matrix composite materials, the specific steps are as follows:

[0008] Selecting raw materials for preparing negative expansion materials, and subjecting the selected raw materials to high-temperature solid-phase sintering to prepare negative expansion materials;

[0009] The prepared negative expansion material is evenly mixed with metal powder by ball milling process to obtain mixed powder;

[0010] The mixed powder is sprayed and molded by cold spray additive manufacturing to obtain a metal matrix composite material with near zero expansion;

[0011] The obtained near-zero expansion metal matrix composite material is heat treated to improve the mechanical properties of the composite material.

[0012] A further technical solution of the present invention is that the process parameters for high-temperature solid-phase sintering of the negative expansion material are: heat preservation at 600-1400° C. for 12-36 hours.

[0013] A further technical solution of the present invention is that the raw material for preparing the negative expansion material is Sc2W3O 12 、Y2W3O 12 、Er2W3O 12 、Yb2W3O 12 、Lu2W3O 12 Sc2Mo3O 12 、Y2Mo3O 12 、Er2Mo3O 12 、Yb2Mo3O 12 、Lu2Mo3O 12 , one or more mixtures of ZrW2O8, HfW2O8, CaZrF6, LiAlSiO4.

[0014] A further technical solution of the present invention is: the parameters of the ball milling process are: a transmission ratio of 1 to 2.25, and a ball milling rate of 100 to 500 r / min.

[0015] A further technical solution of the present invention is: the particle size of the metal powder is 15-53 μm, 53-105 μm or 105-150 μm; the type of the metal powder is aluminum powder, copper powder, nickel powder, titanium powder, alumina powder, nickel titanium or copper titanium powder.

[0016] A further technical solution of the present invention is: the volume ratio of negative expansion material powder and metal powder in the mixed powder is negative expansion material powder: metal powder = 20%:80%, 30%:70%, 40%:60%, 50%:50%, 60%:40%, 70%:30% or 80%:20%.

[0017] A further technical solution of the present invention is: the process parameters of the cold spray additive manufacturing spray molding are: the gas temperature is 200°C to 600°C, the carrier gas type is helium, nitrogen, oxygen, air or argon, and the gas pressure is 1.5 to 3.5 MPa.

[0018] A further technical solution of the present invention is that the process parameters for heat treatment of the near-zero expansion metal-based composite material are: heat preservation at 300-450° C. for 3-6 hours.

[0019] A near-zero expansion metal-based composite material comprises negative expansion material powder and metal powder, wherein the volume ratio of the negative expansion material powder to the metal powder is 20%:80%, 30%:70%, 40%:60%, 50%:50%, 60%:40%, 70%:30% or 80%:20%;

[0020] The negative expansion material powder is composed of Sc2W3O 12 、Y2W3O 12 、Er2W3O 12 、Yb2W3O 12 、Lu2W3O 12 Sc2Mo3O 12 、Y2Mo3O 12 、Er2Mo3O 12 、Yb2Mo3O 12 、Lu2Mo3O 12 , ZrW2O8, HfW2O8, CaZrF6, LiAlSiO4 or one or more mixtures thereof are obtained by high temperature sintering and ball milling;

[0021] The metal powder is aluminum powder, copper powder, nickel powder, titanium powder, alumina powder, nickel titanium or copper titanium powder.

[0022] A further technical solution of the present invention is: the near-zero expansion metal matrix composite material is Y2W3O 12 / Al、Sc2W3O 12 / Al, Er2W3O 12 / Al、Sc2W3O 12 / Cu、Yb2Mo3O 12 / Cu、Sc2Mo3O 12 / Cu、ZrW2O8 / Ag、Lu2Mo3O 12 / Ag or one or more combinations thereof.

[0023] Beneficial Effects

[0024] The beneficial effects of the present invention are: the near-zero expansion metal-based composite material prepared by the method of the present invention can ensure the stability of the dimensions of components and precision structures, low environmental sensitivity, and structural and functional stability under thermal shock conditions, while ensuring the high precision of the material and greatly extending the service life of the material. The specific advantages are analyzed as follows:

[0025] 1. The near-zero expansion metal-based composite material prepared by the present invention has the following advantages by selecting negative expansion material as raw material: ① Controlling thermal expansion coefficient: By compounding negative expansion material with positive expansion material, the purpose of accurately adjusting thermal expansion coefficient is achieved, and the problems of thermal stress, fatigue fracture, microcracks and the like caused by mismatch of thermal expansion coefficient are solved; ② Maintaining dimensional stability: The addition of negative expansion material can significantly reduce the thermal expansion coefficient of metal-based composite materials, and different thermal expansion coefficients can be obtained by adjusting the content of reinforcement to meet various working conditions and improve dimensional stability; ③ Strengthening material strength: In some composite materials, negative expansion material can form a synergistic effect with ordinary metal materials to improve the overall strength and stiffness of the material. For example, adding negative expansion fibers or particles to a metal matrix can produce microscopic changes in stress distribution when the temperature changes, hindering dislocation movement and crack propagation, thereby enhancing the mechanical properties of the composite material; ④ Improving material toughness: Some negative expansion materials themselves have good toughness. After being compounded with ordinary metal materials, they can improve the toughness and impact resistance of metal materials, making the material less likely to break when subjected to external force impact, thereby improving the safety and reliability of the material; ⑤ Isotropy: Most negative expansion materials are isotropic, which can avoid the formation of microcracks during thermal cycles and improve the reliability of the material.

[0026] 2. The near-zero expansion metal-based composite material prepared by the present invention adopts a high-temperature solid-phase sintering method to prepare negative expansion materials. Compared with other methods for preparing negative expansion materials, it has the following advantages: ① Simple process: Usually, it only needs to mix and grind the raw material powders and then sinter them at high temperature, without the need for complex chemical reaction equipment or special treatment processes. Compared with wet chemical methods such as coprecipitation, hydrothermal method, and sol-gel method, it does not require cumbersome steps such as solution preparation, precipitation reaction, and gelation, which reduces the process links, operation difficulty and cost; ② Low equipment requirements: The main equipment is a high-temperature furnace, such as a tube furnace, a box furnace, etc. These equipment are relatively common and easy to operate and maintain. Compared with the microwave sintering method, which requires a special microwave sintering furnace, the discharge plasma sintering method requires a special mold and power supply equipment, and the flash method requires a metal platinum electrode and a complex current control device, the high-temperature solid-phase sintering method has a lower equipment cost and is easier to achieve large-scale production; ③ Good uniformity of composition: At high temperatures, the raw material powders can fully diffuse and react with each other, which is conducive to the formation of a negative expansion material with uniform composition. For some negative expansion materials that require high uniformity of composition, such as rare earth tungstate negative thermal expansion materials, the solid phase reaction process can better ensure the performance stability and consistency of the material; ④ Wide range of applications: Applicable to the preparation of a variety of negative expansion materials, including oxides, fluorides, perovskite structure compounds, etc. For example, rare earth tungstate negative thermal expansion materials, copper pyrophosphate negative thermal expansion materials, etc. can be prepared by high-temperature solid phase sintering, while other methods may only be applicable to specific types of materials or have certain limitations; ⑤ Large-sized materials can be prepared: For some applications that require large-sized negative expansion materials, such as structural components in the fields of aerospace, precision instrument manufacturing, etc., high-temperature solid phase sintering can be used to prepare large-sized block materials by selecting appropriate molds and process parameters, while microwave sintering, spark plasma sintering and other methods may be limited by equipment size and heating uniformity when preparing large-sized materials. Therefore, the present invention adopts a high-temperature sintering method to prepare negative expansion materials.

[0027] 3. The metal-based composite material with near-zero expansion prepared by the present invention has the following advantages over the metal-based composite material prepared by the cold spray additive manufacturing method and the metal-based composite material prepared by the currently common hot pressing sintering method: ① Reaction mechanism: The principle of cold spraying is based on the kinetic energy of high-speed solid particles. The mixed metal-based composite material powder (including metal matrix powder and reinforcement phase powder) is accelerated by a high-speed airflow. When these high-speed particles hit the surface of the matrix, the kinetic energy of the particles is converted into plastic deformation energy. For metal powder, this plastic deformation causes the particles to be tightly combined to form a metal matrix, and the reinforcement phase particles are embedded in the metal matrix by high-speed impact. The whole process does not have a metallurgical reaction in the traditional sense, and is mainly a physical embedding and deformation process. Hot pressing sintering is mainly based on the principles of diffusion and sintering. Under the dual effects of high temperature and pressure, the atoms on the surface of the metal powder particles obtain sufficient energy and begin to diffuse between the particles, forming a necking phenomenon. As time goes on, the bonding between the particles gradually increases, and finally a dense metal matrix is ​​formed. As for the interaction between the reinforcement phase and the metal matrix, on the one hand, it is physical contact and bonding. On the other hand, if a chemical reaction can occur between them at high temperature, new compounds will be generated. These compounds will fill in the interface and thus affect the performance of the material.

[0028] ② Microstructure: The microstructure of metal-based composites prepared by cold spraying is relatively special. The bonding between the metal matrix and the reinforcement phase is mainly mechanical. At the microscopic level, the reinforcement phase particles are impacted by high-speed metal particles and embedded in the metal matrix to form a structure similar to "inlay". This structure makes the distribution of the reinforcement phase in the matrix relatively uniform, and the content and distribution of the reinforcement phase can be controlled by adjusting the spraying parameters. For example, when preparing Al-SiC metal-based composites, SiC particles can be dispersed more evenly in the Al matrix. The metal-based composite material after hot pressing and sintering will present a relatively dense microstructure. Unlike the cold spraying method, some new phases formed by diffusion may appear inside the material after hot pressing and sintering (if a chemical reaction occurs between the metal and the reinforcement phase).

[0029] ③Material properties: Since the cold spraying process is a low-temperature process (generally lower than the melting point of the material), the material will not undergo melting and solidification processes, so some defects generated during thermal processing, such as solidification cracks, can be avoided. The prepared composite material has a high density and can retain the properties of the original powder material, such as the good toughness of the original metal powder and the special properties of the reinforcing phase material. At the same time, due to the bonding method between the reinforcing phase (such as negative expansion material) and the matrix, it can resist thermal expansion and contraction well when the external temperature changes, and improve the dimensional stability of the material. The hot pressing sintering method undergoes a high-temperature process, and the difference in thermal contraction between different phases during cooling causes the material to produce large residual stress. However, if a new phase with a large thermal expansion coefficient is generated during the sintering process, it may have a negative impact on the thermal expansion properties of the composite material. At the same time, if excessive chemical reactions or grain growth occur during the sintering process, it may have an adverse effect on the toughness of the material.

[0030] 4. The near-zero expansion metal-based composite material prepared by the present invention has adjustable thermal expansion properties. By adjusting the ratio and distribution of negative expansion powder and metal powder, the thermal expansion properties of the metal-based composite material can be regulated to a certain extent. The cold spraying process will not change the thermal expansion characteristics of the negative expansion powder, so the negative thermal expansion properties of the negative expansion powder can be used to "compensate" the positive thermal expansion of the metal matrix, thereby preparing a metal-based composite material with a specific thermal expansion coefficient or even near-zero expansion, meeting the requirements for material dimensional stability under different temperature environments.

[0031] 5. The near-zero expansion metal-based composite material prepared by the present invention can form a strong mechanical bond between the reinforcement phase and the matrix metal by adopting a cold spray additive manufacturing method, rather than relying on the formation of intermetallic compounds or excessive metallurgical bonding. This method helps to obtain a more uniform and stable interface bonding, which is beneficial to improving the mechanical properties and wear resistance of the material.

[0032] 6. The near-zero expansion metal matrix composite material mentioned in the present invention has a low cost and simple operation in the preparation method, and does not require the addition of a large amount of chemical reagents or solvents during the spraying process, and has a low overall environmental impact. Compared with the traditional preparation method, the method generates less waste gas, wastewater and solid waste, which helps to reduce environmental pollution and health risks for workers. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is an X-ray diffraction photograph of the near-zero expansion metal matrix composite material prepared in Example 1 of the present invention;

[0034] Figure 2 This is a scanning electron microscope photograph of the near-zero expansion metal matrix composite material prepared in Example 1 of the present invention;

[0035] Figure 3 This is a scanning electron microscope photograph of the interface structure between the negative expansion material (reinforcement phase) and the metal matrix in the near-zero expansion metal matrix composite material prepared in Example 1 of the present invention;

[0036] Figure 4 This is an EDS spectrum photograph of the near-zero expansion metal matrix composite material prepared in Example 1 of the present invention.

[0037] Figure 5 This is a picture of the thermal expansion coefficient of the near-zero expansion metal-based composite material prepared in Example 1 of the present invention. DETAILED DESCRIPTION

[0038] The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, but should not be construed as limiting the present invention.

[0039] Based on the fact that traditional preparation methods often involve high-temperature treatment during the material preparation process, which may cause problems such as oxidation, phase change or grain coarsening of the material, the present invention uses negative expansion materials as thermal expansion inhibitors and mixes them with positive thermal expansion materials (metals) to form composite materials. Adding negative expansion materials to positive thermal expansion materials can make the material have lower or even near-zero thermal expansion characteristics, thereby keeping the thermal expansion coefficient of the composite material stable when the external temperature changes, greatly reducing the residual stress problem caused by thermal expansion and contraction of materials and parts. In addition, the emergence of near-zero expansion materials can ensure the stability of the dimensions of components and precision structures, low environmental sensitivity, and stability of structure and function under hot and cold shock conditions. While ensuring that the material has high precision, it greatly extends the service life of the material and reduces unnecessary losses (such as temperature compensators), and has application potential.

[0040] In one embodiment, a cold spray additive manufacturing method for a near-zero expansion metal matrix composite material comprises the following specific steps:

[0041] Step 1: Select raw materials for preparing negative expansion materials, and perform high-temperature solid-phase sintering on the selected raw materials to prepare negative expansion materials; the process parameters of high-temperature solid-phase sintering are: heat preservation at 600-1400° C. for 12-36 hours;

[0042] For example, the raw material for preparing the negative expansion material is Sc2W3O 12 、Y2W3O 12 、Er2W3O 12 、Yb2W3O 12 、Lu2W3O 12 Sc2Mo3O 12 、Y2Mo3O 12 、Er2Mo3O 12 、Yb2Mo3O12 、Lu2Mo3O 12 , one or more mixtures of ZrW2O8, HfW2O8, CaZrF6, LiAlSiO4.

[0043] Step 2: The prepared negative expansion material is mixed evenly with the metal powder by ball milling process to obtain a mixed powder; the parameters of the ball milling process are: a transmission ratio of 1 to 2.25, and a ball milling rate of 100 to 500 r / min;

[0044] In some embodiments, the particle size of the metal powder is 15 to 53 μm, 53 to 105 μm, or 105 to 150 μm;

[0045] For example, the types of metal powder are aluminum powder, copper powder, nickel powder, titanium powder, alumina powder, nickel titanium or copper titanium powder.

[0046] For example, the volume ratio of the negative expansion material powder and the metal powder in the mixed powder is negative expansion material powder: metal powder = 20%:80%, 30%:70%, 40%:60%, 50%:50%, 60%:40%, 70%:30% or 80%:20%.

[0047] Step 3: The mixed powder is sprayed by cold spray additive manufacturing to obtain a metal-based composite material with near-zero expansion; the process parameters of cold spray additive manufacturing spray molding are: gas temperature is 200°C to 600°C, the carrier gas type is helium, nitrogen, oxygen, air or argon, and the gas pressure is 1.5 to 3.5 MPa;

[0048] The obtained near-zero expansion metal matrix composite material is heat treated at 300-450° C. for 3-6 hours to improve the mechanical properties of the composite material.

[0049] The above technical solution is further described below in conjunction with the accompanying drawings:

[0050] In one embodiment, a cold spray additive manufacturing method for a near-zero expansion metal matrix composite material is provided in accordance with the following steps:

[0051] 1. Using high temperature solid phase sintering method at 600-1400°C for 12-36h to prepare negative expansion material;

[0052] 2. The obtained negative expansion material is mixed evenly with metal powder by ball milling process at a transmission ratio (r) of 1 to 2.25 and a ball milling rate of 100 to 500 r / min;

[0053] 3. The uniformly mixed powder is sprayed and molded by cold spray additive manufacturing to obtain a metal-based composite material with near-zero expansion;

[0054] Fourth, the obtained near-zero expansion metal matrix composite material is heat treated at 300-450°C for 3-6 hours to improve the mechanical properties of the composite material.

[0055] The method of the present invention is to fully mix the synthesized negative expansion material with metal powder, and then prepare a metal-based composite material with near-zero expansion through cold spray additive manufacturing, so that its thermal expansion coefficient remains stable when the external conditions (temperature, pressure) change drastically, greatly reducing the residual stress problem of materials and components caused by thermal expansion and contraction.

[0056] In one embodiment, the negative expansion material is prepared at a temperature of 1200° C. for 12 hours.

[0057] In one embodiment, the negative expansion material is Sc2W3O 12 、Y2W3O 12 、Er2W3O 12 、Yb2W3O 12 、Lu2W3O 12 Sc2Mo3O 12 、Y2Mo3O 12 、Er2Mo3O 12 、Yb2Mo3O 12 、Lu2Mo3O 12 , one or more mixtures of ZrW2O8, HfW2O8, CaZrF6, LiAlSiO4.

[0058] In one embodiment, the ball milling parameters are transmission ratio (r) = 2, ball milling speed = 400r / min.

[0059] In one embodiment, the metal powder has a particle size of 15-53 μm, 53-105 μm, 105-150 μm, etc.

[0060] In one embodiment, the metal particles are aluminum powder, copper powder, nickel powder, titanium powder, alumina powder, nickel titanium, copper titanium powder, etc.

[0061] In one embodiment, the volume ratio of the mixed powder is negative expansion powder: metal powder = 20%:80%, 30%:70%, 40%:60%, 50%:50%, 60%:40%, 70%:30%, 80%:20%, etc.

[0062] In one embodiment, the process parameters of the cold spraying equipment include a gas temperature of 200°C to 600°C, a carrier gas type of helium (He), nitrogen (N2), oxygen (O2), air, and argon (Ar), and a gas pressure of 1.5 to 3.5 MPa.

[0063] In one embodiment, the metal matrix composite material is Y2W3O 12 / Al、Sc2W3O 12 / Al, Er2W3O 12 / Al、Sc2W3O 12 / Cu、Yb2Mo3O 12 / Cu、Sc2Mo3O 12 / Cu、ZrW2O8 / Ag、Lu2Mo3O 12 / Ag, etc., one or more combinations as mentioned above.

[0064] In one embodiment, the heat treatment temperature is 400° C. and the holding time is 4 hours.

[0065] In one embodiment, a cold spray additive manufacturing method for a near-zero expansion metal matrix composite material is performed according to the following steps:

[0066] Step 1. This experiment uses a high-temperature solid-phase sintering method to prepare negative expansion materials. The specific steps are to use anhydrous ethanol as a ball milling medium, fully mix the stoichiometric Y2O3 (Aladdin, 99.99%) and WO3 (Aladdin, 99.99%) powders in a stoichiometric ratio of 1:3, and then ball mill for 10 hours. After drying at 75°C for 48 hours, the mixed powder is poured into a platinum crucible using a solid-phase sintering method, and the platinum crucible is placed in a muffle furnace and heated to 1100°C. After keeping warm for 20 hours, Y2W3O 12 powder, and the obtained Y2W3O 12 The powder was subjected to a final ball milling process to obtain fine Y2W3O 12 powder;

[0067] Step 2: Get the Y2W3O 12 The powder is ball-milled and mixed evenly with metal powder to prepare mixed powders of different proportions;

[0068] Step 3: The uniformly mixed powder is sprayed and molded by cold spray additive manufacturing to obtain a metal-based composite material with near-zero expansion;

[0069] Step 4: heat-treat the obtained near-zero expansion metal matrix composite material at 300-450° C. for 3-6 hours to improve the mechanical properties of the composite material.

[0070] Preferably, the preparation method of the negative expansion material in step 1 is high temperature solid phase sintering.

[0071] Preferably, the negative expansion material in step 1 is Y2W3O 12 .

[0072] Preferably, the ball milling parameters in step 1 are transmission ratio (r) = 2.25, and ball milling rate = 300 r / min.

[0073] Preferably, the particle size of the metal powder in step 2 is 15 to 53 μm.

[0074] Preferably, the metal powder in step 2 is aluminum powder.

[0075] Preferably, the mixed powder ratio in step 2 is Y2W3O 12 :Al=30%:70%, 40%:60%, 50%:50%, 60%:40%, 70%:30%, 80%:20%, etc.

[0076] Preferably, the process parameters of the cold spraying equipment described in step three are a gas temperature of 400° C., a carrier gas type of N2, and a gas pressure of 2.5 MPa.

[0077] Preferably, the near-zero expansion metal matrix composite material described in step 3 is Y2W3O 12 / Al.

[0078] Preferably, the heat treatment temperature in step 4 is 300° C. and the insulation time is 3 hours.

[0079] In order to prove that the Y2W3O prepared by the present invention 12 The Y2O3 / Al composite material has a near-zero expansion effect. First, Y2O3 powder and WO3 powder are mixed in a stoichiometric ratio of 1:3 and ball-milled and poured into a platinum crucible. The platinum crucible is placed in a muffle furnace and heated to 1100°C. After keeping the temperature for 20 hours, Y2W3O 12 Powder, the XRD pattern of the powder is as follows Figure 1 As shown, the resulting Y2W3O 12 The powder was subjected to a final ball milling process to obtain fine Y2W3O 12 The powder is fully mixed with spherical Al powder with a particle size of 15 to 53 microns to prepare mixed powders of different proportions. The mixed powder is sprayed by cold spray additive manufacturing to obtain Y2W3O with near zero expansion. 12 / Al composite material, its XRD picture is as follows Figure 1 As shown, the near-zero expansion of Y2W3O 12 The deposition effect of / Al mixed powder on the substrate is as follows Figure 2 As shown, the near-zero expansion of Y2W3O 12 The scanning electron microscope photograph of the interface structure between the / Al composite material and the substrate is shown in Figure 3 As shown, the near-zero expansion Y2W3O 12 EDS spectrum of / Al composite materials is shown in Figure 4As shown, the near-zero expansion of Y2W3O 12 The thermal expansion coefficient of the / Al composite material is Figure 5 shown.

[0080] Figure 1 This is an XRD photo of the metal-based composite material with near-zero expansion in this embodiment. It can be seen from the photo that the negative expansion Y2W3O can be accurately prepared by the solid phase sintering method. 12 The material is completely free of other impurities (such as WO3, Y2O3, etc.) in the reaction. Y2W3O prepared by cold spraying 12 / Al composites only have Y2W3O 12 The peaks with Al do not introduce any new phase.

[0081] Figure 2 This is the near-zero expansion Y2W3O prepared by the cold spray additive manufacturing method in this embodiment. 12 SEM photo of the / Al composite material. It can be seen from the figure that the negative expansion material (Y2W3O 12 ) is evenly and densely deposited on the substrate, and the deposition effect is relatively good, thereby keeping the thermal expansion coefficient of the composite material stable when the external temperature changes.

[0082] Figure 3 The prepared near-zero expansion Y2W3O 12 SEM photo of the interface structure between the / Al composite material and the substrate. 12 The interface between the Al / Al composite material and the matrix is ​​closely bonded, the degree of interface reaction is low, the thickness of the interface reaction layer is very thin, and the interface bonding strength is high and not easy to break.

[0083] Figure 4 The near-zero expansion Y2W3O prepared in this example 12 EDS spectrum of the prepared Y2W3O 12 The bright white coating in the / Al composite material is Y2W3O 12 , the black part is Al, and both are evenly distributed with less agglomeration.

[0084] Figure 5 The near-zero expansion Y2W3O prepared in this example 12 Thermal expansion coefficient of Y2W3O / Al composite materials. 12 It has been calculated that the thermal expansion coefficient of the Al / Al composite material is infinitely close to 0, which indicates that doping Al (metal) with negative expansion materials can significantly reduce its thermal expansion coefficient and make it have better mechanical properties.

[0085] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention without departing from the principles and intent of the present invention.

Claims

1. A cold spray additive manufacturing method for near-zero expansion metal matrix composite materials, characterized in that The specific steps are as follows: Selecting raw materials for preparing negative expansion materials, and subjecting the selected raw materials to high-temperature solid-phase sintering to prepare negative expansion materials; The prepared negative expansion material is evenly mixed with metal powder by ball milling process to obtain mixed powder; The mixed powder is sprayed and molded by cold spray additive manufacturing to obtain a metal matrix composite material with near zero expansion; The obtained near-zero expansion metal matrix composite material is heat treated to improve the mechanical properties of the composite material.

2. A cold spray additive manufacturing method for a near-zero expansion metal matrix composite material according to claim 1, characterized in that: The process parameters for high-temperature solid-phase sintering of the negative expansion material are: keeping warm at 600-1400° C. for 12-36 hours.

3. A cold spray additive manufacturing method for a near-zero expansion metal matrix composite material according to claim 2, characterized in that: The raw material for preparing the negative expansion material is Sc2W3O 12 、Y2W3O 12 、Er2W3O 12 、Yb2W3O 12 、Lu2W3O 12 Sc2Mo3O 12 、Y2Mo3O 12 、Er2Mo3O 12 、Yb2Mo3O 12 、Lu2Mo3O 12 , ZrW2O8, HfW2O8, CaZrF6, LiAlSiO4 or a mixture of one or more of the following:

4. The cold spray additive manufacturing method of a near-zero expansion metal matrix composite material according to claim 3, characterized in that: The parameters of the ball milling process are: a transmission ratio of 1 to 2.25, and a ball milling rate of 100 to 500 r / min.

5. A cold spray additive manufacturing method for a near-zero expansion metal matrix composite material according to claim 4, characterized in that: The particle size of the metal powder is 15-53 μm, 53-105 μm or 105-150 μm; the type of the metal powder is aluminum powder, copper powder, nickel powder, titanium powder, alumina powder, nickel titanium or copper titanium powder.

6. A cold spray additive manufacturing method for a near-zero expansion metal matrix composite material according to claim 5, characterized in that: The volume ratio of the negative expansion material powder and the metal powder in the mixed powder is negative expansion material powder:metal powder=20%:80%, 30%:70%, 40%:60%, 50%:50%, 60%:40%, 70%:30% or 80%:20%.

7. A cold spray additive manufacturing method for a near-zero expansion metal matrix composite material according to claim 6, characterized in that: The process parameters of the cold spray additive manufacturing spray molding are: gas temperature is 200°C to 600°C, the carrier gas type is helium, nitrogen, oxygen, air or argon, and the gas pressure is 1.5 to 3.5 MPa.

8. A cold spray additive manufacturing method for near-zero expansion metal matrix composite materials according to claim 7, characterized in that: The process parameters for heat treatment of the near-zero expansion metal-based composite material are: heat preservation at 300-450° C. for 3-6 hours.

9. A near-zero expansion metal matrix composite material, obtained by the cold spraying additive manufacturing method of the near-zero expansion metal matrix composite material according to any one of claims 1 to 8; characterized in that: It comprises negative expansion material powder and metal powder, wherein the volume ratio of the negative expansion material powder to the metal powder is 20%:80%, 30%:70%, 40%:60%, 50%:50%, 60%:40%, 70%:30% or 80%:20%; The negative expansion material powder is composed of Sc2W3O 12 、Y2W3O 12 、Er2W3O 12 、Yb2W3O 12 、Lu2W3O 12 Sc2Mo3O 12 、Y2Mo3O 12 、Er2Mo3O 12 、Yb2Mo3O 12 、Lu2Mo3O 12 , ZrW2O8, HfW2O8, CaZrF6, LiAlSiO4 or one or more mixtures thereof are obtained by high temperature sintering and ball milling; The metal powder is aluminum powder, copper powder, nickel powder, titanium powder, alumina powder, nickel titanium or copper titanium powder.

10. A near-zero expansion metal matrix composite material according to claim 9, characterized in that: The near-zero expansion metal matrix composite material is Y2W3O 12 / Al、Sc2W3O 12 / Al, Er2W3O 12 / Al、Sc2W3O 12 / Cu、Yb2Mo3O 12 / Cu、Sc2Mo3O 12 / Cu、ZrW2O8 / Ag、Lu2Mo3O 12 / Ag or one or more combinations thereof.

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