Double-metal composite material with spiral layered structure and preparation method of double-metal composite material

Abstract

The invention belongs to the technical field of metal-based composite materials, and discloses a double-metal composite material with a spiral layered structure and a preparation method thereof.The double-metal composite material with the spiral layered structure comprises framework metal and filling metal, the framework metal is of a spiral layered structure, and the spiral angle between every two adjacent layers is 30 degrees or 60 degrees or 90 degrees; the filling metal is filled in the gap of the framework metal; the volume fraction of the framework metal is 15%-75%, and the rest space is filled with the filling metal; the melting point of the framework metal is higher than that of the filling metal. According to the preparation method disclosed by the invention, the microstructure and the macroscopic form of the bimetallic composite material can be flexibly regulated and controlled, and the design and construction of a complex macro-microstructure are realized; the obtained double-metal composite material with the spiral layered structure is excellent in compressive strength, elastic modulus, corrosion resistance and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of metal matrix composite materials, and in particular relates to a spiral layered bimetallic composite material and a preparation method thereof. Background Art

[0002] The corresponding relationship between material properties and microstructure is becoming increasingly clear. Customizing the mechanical properties or functional characteristics of composite materials through multi-scale structural design is one of the reasonable and feasible ways, and it has broad application prospects in fields such as aerospace and electronics industries. At present, bimetallic composite materials are usually prepared by stirring casting, powder metallurgy and other methods. For example, the Chinese invention patent application number CN202011607989.4, the publication number CN112813293A, and the invention name "A metal titanium particle reinforced magnesium-based composite material and its vacuum stirring casting method and application" successfully prepared a metal titanium particle reinforced magnesium-based composite material by a vacuum stirring casting method; another example is the Chinese invention patent application number CN201710114670.X, the publication number CN106903307B, and the invention name "A powder metallurgy preparation method for co-formed and co-sintered tungsten alloy / steel composite material" The patent adopts a powder metallurgy pressing process to prepare a tungsten alloy / steel composite material, but the reinforcement particles in the above-mentioned metal-based composite material are uniformly distributed in the metal matrix, and its strengthening and toughening effect is limited, and there are great limitations in constructing complex shapes and regulating fine structures.

[0003] In recent years, 3D printing has developed into a new method for preparing engineering materials with multi-scale structures. The Chinese invention patent application number is CN202110244923.1, the publication number is CN113172724A, and the invention name is "A controllable network ceramic / metal composite material preparation process". The patent reported that it used photocuring 3D printing technology combined with vacuum pressure infiltration technology to prepare Al2O3 / Al composite materials with a network structure. However, the above patents use photocuring 3D printing technology and pressure infiltration technology, and are ceramic / metal material systems. From the perspectives of economic cost, controllability, and universal applicability, the combination of ink direct writing technology (DIW) and pressureless infiltration technology is one of the ideal ways to make bimetallic composite materials with complex macroscopic shapes and fine microstructures. DIW can flexibly control the macroscopic shape and microstructure of the printed material to obtain a porous skeleton with a pre-set structure. Pressureless infiltration technology has the advantages of simple operation, low cost, strong versatility and near net shape. It can significantly improve the density and compressive strength of composite materials by filling the holes in the skeleton with metal. According to literature search, there are no reports on the preparation of spiral layered bimetallic composite materials and their specific methods by ink direct writing printing and pressureless infiltration technology at home and abroad. Summary of the invention

[0004] The key problem to be solved by the present invention is that the bimetallic composite material produced by the traditional process has a uniform microstructure, a simple macroscopic shape, and a long production cycle. The present invention provides a short-cycle preparation process for flexibly regulating the microstructure and macroscopic shape, and prepares a bimetallic composite material with a spiral layered structure.

[0005] In order to achieve the above object, the technical solution of the present invention is achieved as follows:

[0006] A spiral layered bimetallic composite material comprises a skeleton metal and a filler metal, wherein the skeleton metal has a spiral layered structure, and the spiral angle between two adjacent layers is 30°, 60° or 90°; the filler metal is filled in the gap of the skeleton metal; the volume fraction of the skeleton metal is 15% to 75%, and the remaining space is the filler metal; the melting point of the skeleton metal is higher than that of the filler metal.

[0007] The material of the skeleton metal is stainless steel; the stainless steel is 316L stainless steel; the material of the filler metal is pure copper or copper alloy.

[0008] The thickness of each layer of the skeleton metal is 260-2000 μm.

[0009] A method for preparing a spiral layered bimetallic composite material comprises the following steps:

[0010] (1) preparing a slurry for constructing a skeleton metal; (2) obtaining a skeleton metal blank with a spiral layered structure by using an ink direct writing printing technique, and then obtaining a skeleton metal with a predetermined pore structure after drying and high-temperature sintering; (3) placing a filler metal on top of the skeleton metal and using a melt infiltration method to obtain a spiral layered bimetallic composite material.

[0011] The slurry is prepared by dissolving a dispersant in deionized water, mixing the mixture with stainless steel powder, and performing ball milling and vacuum stirring to degas, thereby obtaining a slurry;

[0012] The mass ratio of the deionized water to the skeleton metal powder is 1:(5-20), and the mass of the added dispersant is 20-40wt.% of the deionized water; the solid content in the slurry is 35-65vol%.

[0013] The dispersant is one or more of Pluronic F-127, sodium alginate, sodium polymethacrylate and sodium carboxymethyl cellulose; the process conditions of ball milling are: mechanical stirring for 1 to 10 hours; the process conditions of vacuum stirring and degassing are: degassing for 10 to 20 minutes, and the stirring speed is 30 to 80 r / min.

[0014] The preparation method of the skeleton metal blank is: filling the slurry into the ink direct writing printer container at room temperature, then extruding it at 0.1-0.5 MPa, and printing it according to a preset three-dimensional model to obtain a spiral layered skeleton metal blank.

[0015] The process parameters of high temperature sintering in step (2) are: vacuum degree is 5-30Pa, in an inert gas atmosphere, firstly heating to 450-550°C at 5°C / min-10°C / min and keeping warm for 80-90min, then continuing to heating to 1100-1400°C at 5°C / min-10°C / min and keeping warm for 1-2h.

[0016] The melt infiltration in step (3) is pressureless infiltration, and the process parameters are: evacuating to 0.01-10Pa at room temperature, heating to 450-550°C at 5°C / min-10°C / min and keeping warm for 0.5-1.5h, then continuing to heat to 1100-1400°C at 5°C / min-10°C / min and keeping warm for 0.3-1.5h.

[0017] Beneficial effects of the present invention:

[0018] (1) The spiral layered porous skeleton produced by the ink direct writing printing process of the present invention can have a customized irregular shape, a layered rotating stacking arrangement, and a uniform microscopic pore structure, which is difficult to obtain by traditional manufacturing processes. The new process proposed by the present invention has made great progress in the structural regulation of the skeleton, realizing the precise control of the macro-microstructure, and can also flexibly adjust the macro-microstructure of the skeleton metal by changing the process parameters to meet different performance requirements.

[0019] (2) The present invention utilizes a pressureless infiltration process to fill the filler metal into the skeleton metal, thereby successfully preparing an overall dense bimetallic composite material. The method is simple in process, has low requirements on equipment, can prepare parts with relatively complex shapes, and the prepared composite material can almost achieve near-net shape, greatly reducing the preparation and processing costs.

[0020] (3) The technology provided by the present invention is novel and practical, has strong universal applicability and scalability, can be applied to a variety of material systems, helps to broaden the design space of metal composite materials, and the method is simple and easy to implement, can be mass-produced, and has great potential for industrial application. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. 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 creative work.

[0022] Figure 1 It is a schematic diagram of the ink direct writing printing process of the present invention;

[0023] Figure 2 It is a schematic diagram of the design of the 30° spiral layered structure of the present invention;

[0024] Figure 3 This is a macroscopic morphology of the 30° helical layered 316L skeleton described in the present invention;

[0025] Figure 4 This is a physical picture of the 30° spiral Cu / 316L metal composite material of the present invention;

[0026] Figure 5 It is a schematic diagram of the design of the 60° spiral layered structure of the present invention;

[0027] Figure 6 This is a macroscopic morphology of the 60° helical layered 316L skeleton described in the present invention;

[0028] Figure 7 It is a schematic diagram of the design of the 90° spiral layered structure of the present invention;

[0029] Figure 8 This is a macroscopic morphology of the 90° helical layered 316L skeleton described in the present invention;

[0030] Fig. 9 It is the compressive strength of the Cu / 316L composite material at a rotation angle of 90° described in the present invention. DETAILED DESCRIPTION

[0031] The following embodiments all use low-cost, widely available 316L powder and copper to verify the concept of the present invention, but the key to the present invention is to use ink direct writing printing to control the macro-microstructure, and then combine the pressureless infiltration technology to fill the metal melt on this basis to obtain a bimetallic composite material with a complex and customizable structure. The realization of these beneficial effects does not depend on the choice of material system, so the technology provided by the present invention can be generally applied to common metal materials such as silver, titanium, tungsten, etc. In addition, based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative labor are within the scope of protection of the present invention.

[0032] Example 1

[0033] A spiral layered bimetallic composite material, the preparation process is as follows Figure 1 The specific preparation method comprises the following steps:

[0034] (a) preparing a water-based slurry: dissolving 4.95 g of dispersant F-127 in 16.5 g of deionized water, adding 184.3 g of 316L powder, and then stirring for 1.5 h by mechanical stirring to prepare a slurry. The stirred slurry is degassed by vacuum stirring for 20 min at a stirring speed of 80 r / min to prepare a water-based slurry;

[0035] (b) Ink direct writing printing: Solidworks software was used to design and create a spiral layered 3D model (length 32.6 mm, width 32.6 mm, height 15 mm, 25 layers, spacing 1 mm) with a layer-by-layer rotation angle of 30°. Figure 2 Then, the designed model is imported into Cura software for slicing, a file format that can be used for a direct writing printer is obtained, and a printing task is executed to obtain a spiral layered structure skeleton blank;

[0036] (c) Drying and high temperature sintering:

[0037] The skeleton blank was dried naturally at room temperature and then placed in a high-temperature sintering furnace. Argon was used for protection during the sintering process. The temperature was raised to 500°C at 5°C / min and kept at this temperature for 90 minutes, then raised to 1200°C at 5°C / min and kept at this temperature for 90 minutes. The temperature was then lowered to room temperature at 5°C / min to obtain a porous stainless steel skeleton with a spiral layered structure, such as Figure 3 As shown;

[0038] (d) Pressureless melt infiltration

[0039] The porous stainless steel skeleton and pure copper were placed in an alumina crucible in sequence, and then the crucible was placed in a vacuum furnace. After the device was sealed, it was evacuated to 10Pa at room temperature, and then the temperature was increased to 500°C at 10°C / min and kept warm for 30min, and then continued to increase the temperature to 1000°C at 5°C / min and kept warm for 30min, and then continued to increase the temperature to 1150°C at 5°C / min, kept warm for 45min, and then cooled to 500°C at 10°C / min, and then cooled to room temperature with the furnace, and finally a spiral layered structure Cu / 316L composite material was obtained, such as Figure 4 shown.

[0040] Example 2

[0041] The difference between this embodiment and embodiment 1 lies in the design of the skeleton blank in the ink direct writing printing process: the spiral layered three-dimensional model (length 32.6mm, width 32.6mm, height 15mm, number of layers 25, spacing 1mm) with a layer-by-layer rotation angle of 60° is designed and created using the software Solidworks. Figure 5 Then, the designed model is imported into Cura software for slicing, and a file format that can be used for a direct-write printer is obtained. The printing task is then executed to obtain a spiral layered structure skeleton blank. After drying and sintering, a spiral layered structure porous stainless steel skeleton is obtained, as shown in FIG. Figure 6 Finally, the spiral layered structure Cu / 316L composite material was obtained through pressureless melt infiltration.

[0042] Example 3

[0043] The difference between this embodiment and embodiment 1 lies in the design of the skeleton blank in the ink direct writing printing process: the spiral layered three-dimensional model (length 32.6mm, width 32.6mm, height 15mm, number of layers 25, spacing 1mm) with a layer-by-layer rotation angle of 90° is designed and created using the software Solidworks. Figure 7 Then, the designed model is imported into Cura software for slicing, and a file format that can be used for a direct-write printer is obtained. The printing task is then executed to obtain a spiral layered structure skeleton blank. After drying and sintering, a spiral layered structure porous stainless steel skeleton is obtained, as shown in FIG. Figure 8 Finally, the spiral layered structure Cu / 316L composite material was obtained through pressureless melt infiltration.

[0044] Subsequently, the compressive performance of the obtained Cu / 316L composite material was tested: before the experiment, the sample size was cut into 7.5mm×7.5mm×7.5mm, and the upper and lower surfaces of the test sample were polished with 400-grit sandpaper to ensure that it was parallel to the indenter of the universal mechanical testing machine to obtain accurate data. In the experiment, the pressure threshold of the universal mechanical testing machine was set to 9KN, and the indenter rate was 0.5mm / min. The test was started after the preparation was complete. After the test, the compressive stress-strain curve was obtained.

[0045] It can be seen that the performance of the composite material shows anisotropic characteristics, especially when the strain is less than 10%. At the same time, the compression performance in the 3 / 4 direction is better than that in the 1 / 2 direction (3 / 4 is perpendicular to the porous direction, and 1 / 2 is parallel to the porous direction). This is because the composite material has a stronger bearing capacity due to the interlocking structure formed perpendicular to the porous structure than parallel to the porous structure. In addition, during the compression process, the composite material does not undergo destructive fracture, and the stress does not drop sharply, showing continuous and stable deformation, such as Fig. 9 shown.

[0046] Example 4

[0047] A spiral layered bimetallic composite material, the specific preparation method comprises the following steps:

[0048] (a) preparing a water-based slurry: dissolving 5 g of dispersant sodium polymethacrylate in 25 g of deionized water, adding 125 g of 316L powder, and then stirring for 1 h by mechanical stirring to prepare a slurry. The stirred slurry is degassed by vacuum stirring for 15 min at a stirring speed of 30 r / min to prepare a water-based slurry;

[0049] (b) Ink direct writing printing: Use the software Solidworks to design and create a spiral layered 3D model (length 32.6mm, width 32.6mm, height 15mm, 25 layers, spacing 0.5mm) with a layer-by-layer rotation angle of 30°. Then, import the designed model into the Cura software for slicing to obtain a file format that can be used for a direct writing printer, and execute the printing task. The extrusion pressure is 0.1MPa to obtain a spiral layered structure skeleton blank;

[0050] (c) Drying and high temperature sintering:

[0051] The skeleton blank was dried naturally at room temperature and then placed in a high-temperature sintering furnace. Argon gas was used throughout the sintering process, and the temperature was raised to 450°C at 8°C / min and kept at this temperature for 80 minutes, then raised to 1400°C at 10°C / min and kept at this temperature for 60 minutes. The temperature was then lowered to room temperature at 5°C / min to obtain a porous stainless steel skeleton with a spiral layered structure.

[0052] (d) Pressureless melt infiltration

[0053] The porous stainless steel skeleton and pure copper were placed in an alumina crucible in turn, and then the crucible was placed in a vacuum furnace. After the device was sealed, it was evacuated to 5 Pa at room temperature, and then the temperature was increased to 450°C at 5°C / min and kept for 35 min, and then continued to be heated to 1000°C at 10°C / min and kept for 30 min, and then continued to be heated to 1100°C at 10°C / min, kept for 60 min, and then cooled to 500°C at 10°C / min, and then cooled to room temperature with the furnace, and finally a spiral layered structure Cu / 316L composite material was obtained.

[0054] Example 5

[0055] A spiral layered bimetallic composite material, the specific preparation method comprises the following steps:

[0056] (a) preparing a water-based slurry: dissolving 5 g of a dispersant sodium polymethacrylate in 12.5 g of deionized water, adding 250 g of 316L powder, and then stirring for 10 h by mechanical stirring to prepare a slurry. The stirred slurry is degassed by vacuum stirring for 10 min at a stirring speed of 50 r / min to prepare a water-based slurry;

[0057] (b) Ink direct writing printing: Use the software Solidworks to design and create a spiral layered 3D model (length 32.6mm, width 32.6mm, height 15mm, 25 layers, spacing 1.5mm) with a layer-by-layer rotation angle of 30°. Then, import the designed model into the Cura software for slicing to obtain a file format that can be used for a direct writing printer, and execute the printing task. The extrusion pressure is 0.5MPa to obtain a spiral layered structure skeleton blank;

[0058] (c) Drying and high temperature sintering:

[0059] The skeleton blank was dried naturally at room temperature and then placed in a high-temperature sintering furnace. Argon gas was used throughout the sintering process, and the temperature was raised to 550°C at 10°C / min and kept for 90 minutes, then raised to 1100°C at 10°C / min and kept for 120 minutes. Then the temperature was lowered to room temperature at 5°C / min to obtain a porous stainless steel skeleton with a spiral layered structure.

[0060] (d) Pressureless melt infiltration

[0061] The porous stainless steel skeleton and pure copper were placed in an alumina crucible in turn, and then the crucible was placed in a vacuum furnace. After the device was sealed, it was evacuated to 1 Pa at room temperature, and then the temperature was increased to 550°C at 8°C / min and kept warm for 60 min, and then continued to be heated to 1200°C at 10°C / min and kept warm for 60 min, and then continued to be heated to 1300°C at 10°C / min, kept warm for 30 min, and then cooled to 500°C at 10°C / min, and then cooled to room temperature with the furnace, and finally a spiral layered structure Cu / 316L composite material was obtained.

[0062] Example 6

[0063] A spiral layered bimetallic composite material, the specific preparation method comprises the following steps:

[0064] (a) preparing a water-based slurry: dissolving 5 g of sodium carboxymethyl cellulose as a dispersant in 20 g of deionized water, adding 200 g of 316L powder, and then stirring for 5 h by mechanical stirring to prepare a slurry. The stirred slurry is degassed by vacuum stirring for 10 min at a stirring speed of 50 r / min to prepare a water-based slurry;

[0065] (b) Ink direct writing printing: Use the software Solidworks to design and create a spiral layered 3D model (length 32.6mm, width 32.6mm, height 15mm, 25 layers, spacing 1mm) with a layer-by-layer rotation angle of 30°. Then, import the designed model into the Cura software for slicing to obtain a file format that can be used for a direct writing printer, and execute the printing task. The extrusion pressure is 0.3MPa to obtain a spiral layered structure skeleton blank;

[0066] (c) Drying and high temperature sintering:

[0067] The skeleton blank was dried naturally at room temperature and then placed in a high-temperature sintering furnace. Argon gas was used throughout the sintering process, and the temperature was raised to 550°C at 5°C / min and kept for 85 minutes, then raised to 1300°C at 8°C / min and kept for 120 minutes. Then the temperature was lowered to room temperature at 5°C / min to obtain a porous stainless steel skeleton with a spiral layered structure.

[0068] (d) Pressureless melt infiltration

[0069] The porous stainless steel skeleton and pure copper were placed in an alumina crucible in turn, and then the crucible was placed in a vacuum furnace. After the device was sealed, it was evacuated to 0.1 Pa at room temperature, and then the temperature was increased to 500°C at 10°C / min and kept warm for 90 min, and then continued to be heated to 1100°C at 5°C / min and kept warm for 30 min, and then continued to be heated to 1400°C at 10°C / min and kept warm for 30 min, and then cooled to 500°C at 10°C / min, and then cooled to room temperature with the furnace, and finally a spiral layered structure Cu / 316L composite material was obtained.

[0070] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A spiral layered bimetallic composite material, characterized in that: It comprises a skeleton metal and a filler metal, wherein the skeleton metal has a spiral layered structure, and the spiral angle between two adjacent layers is 30°, 60° or 90°; the filler metal is filled in the gaps of the skeleton metal; the volume fraction of the skeleton metal is 15% to 75%, and the remaining space is the filler metal; the melting point of the skeleton metal is higher than that of the filler metal.

2. The spiral layered bimetallic composite material according to claim 1, characterized in that: The material of the skeleton metal is stainless steel; the stainless steel is 316L stainless steel; the material of the filler metal is pure copper or copper alloy.

3. The spiral layered bimetallic composite material according to claim 2, characterized in that: The thickness of each layer of the skeleton metal is 260-2000 μm.

4. The method for preparing the spiral layered bimetallic composite material according to any one of claims 1 to 3, characterized in that: The following steps are involved: (1) preparing a slurry for constructing a skeleton metal; (2) obtaining a skeleton metal blank with a spiral layered structure by using an ink direct writing printing technique, and then obtaining a skeleton metal with a predetermined pore structure after drying and high-temperature sintering; (3) placing a filler metal on top of the skeleton metal and using a melt infiltration method to obtain a spiral layered bimetallic composite material.

5. The method for preparing the spiral layered bimetallic composite material according to claim 4, characterized in that: The preparation method of the slurry is: dissolving the dispersant in deionized water, mixing the dispersant with the skeleton metal powder, and performing ball milling and vacuum stirring to degas to obtain the slurry.

6. The method for preparing the spiral layered bimetallic composite material according to claim 5, characterized in that: The mass ratio of the deionized water to the skeleton metal powder is 1:(5-20), the mass of the dispersant is 20-40wt.% of the deionized water; the solid content in the slurry is 35-65vol%.

7. The spiral layered bimetallic composite material and the preparation method thereof according to claim 6, characterized in that: The dispersant is one or more of Pluronic F-127, sodium alginate, sodium polymethacrylate and sodium carboxymethyl cellulose; the process conditions of ball milling are: mechanical stirring for 1 to 10 hours; the process conditions of vacuum stirring and degassing are: degassing for 10 to 20 minutes, and the stirring speed is 30 to 80 r / min.

8. The spiral layered bimetallic composite material and the preparation method thereof according to claim 4, characterized in that: The preparation method of the skeleton metal blank is: filling the slurry into the ink direct writing printer container at room temperature, then extruding it at 0.1-0.5 MPa, and printing it according to a preset three-dimensional model to obtain a spiral layered skeleton metal blank.

9. The method for preparing the spiral layered bimetallic composite material according to claim 4, characterized in that: The process parameters for high temperature sintering in step (2) are as follows: in an inert gas atmosphere, firstly heat to 450-550°C at 5°C / min-10°C / min and keep warm for 80-90 minutes, then continue to heat to 1100-1400°C at 5°C / min-10°C / min and keep warm for 1-2 hours.

10. The method for preparing the spiral layered bimetallic composite material according to claim 4, characterized in that: The process parameters of melt infiltration in step (3) are: evacuating to 0.01-10Pa at room temperature, heating to 450-550°C at 5°C / min-10°C / min and keeping warm for 0.5-1.5h, then continuing to heat to 1100-1400°C at 5°C / min-10°C / min and keeping warm for 0.3-1.5h.

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