Ceramic particle reinforced magnesium-based composite material and forming method thereof

Abstract

The invention belongs to the technical field of magnesium-based composite materials, and particularly relates to a ceramic particle reinforced magnesium-based composite material and a forming method thereof.The forming method comprises the steps that (1) material pretreatment is conducted, specifically, magnesium powder, aluminum powder, zinc powder, manganese powder, monatomic silicon, copper powder, titanium carbide and metal gadolinium powder are weighed according to the formula amount and then sequentially subjected to ball milling, screening and drying, and the ceramic particle reinforced magnesium-based composite material is obtained; (2) preprocessing the model; (3) assembling; (4) 3D printing; the forming method has the characteristics of remarkably reducing the working procedures, reducing the labor cost and improving the material strength, and meanwhile, the problem of ceramic particle aggregation is solved.

Description

Technical Field

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

[0002] Ceramic particle reinforced magnesium-based composites have the characteristics of high specific strength, high specific stiffness, high modulus and light weight, and can achieve the effect of reducing the weight of structural parts.

[0003] At present, the manufacturing method of ceramic particle reinforced magnesium-based composite materials is prepared in the traditional casting and melting mode. The raw materials of magnesium-based composite materials are first calculated and proportioned, and then the alloy is melted and cast, and the magnesium-based composite materials are obtained after cooling. The disadvantages of the traditional manufacturing method are: 1. The traditional melting and casting manufacturing method has complicated processes and high labor costs. 2. The strength of magnesium-based composite materials prepared by traditional methods cannot meet the high-strength requirements under current engineering application conditions. 3. The high melt viscosity makes it difficult to disperse ceramic particles and they are easy to agglomerate in the alloy melt, which in turn reduces the mechanical properties of magnesium-based composite materials.

[0004] The Chinese patent application number CN202111082012.X discloses a 3DP preparation process for improving the strength and corrosion resistance of magnesium alloys, comprising the following steps: 1) mixing magnesium alloy powder, ceramic powder and carbide powder in proportion; 2) importing the shape of the product to be printed into the computer control system, and printing the mixed powder and glue obtained in step 1) in a 3D printer by alternate spraying to obtain a blank of the required shape; 3) drying the blank obtained in step 2), and then degreasing and sintering at 300℃ to 450℃ in a protective atmosphere or vacuum; 4) sintering the blank obtained in step 3) at a high temperature of 580℃ to 660℃ in a protective atmosphere or vacuum, and then cooling to room temperature. However, this method has high energy consumption and the mechanical properties are still not ideal. Summary of the invention

[0005] In view of the deficiencies in the prior art, the present invention provides a ceramic particle reinforced magnesium-based composite material and a molding method thereof.

[0006] This is achieved specifically through the following technical solutions:

[0007] A ceramic particle reinforced magnesium-based composite material comprises, by molar percentage, 9.0-9.5% Al, 0.5-0.9% Zn, 0.015-0.03% Mn, 0.01-0.03% Si, 0.001-0.01% Cu, 3-8% TiC, 3-5% Gd, and the balance is Mg.

[0008] A method for forming a ceramic particle reinforced magnesium-based composite material comprises the following steps:

[0009] (1) Material pretreatment: magnesium powder, aluminum powder, zinc powder, manganese powder, elemental silicon, copper powder, titanium carbide, and metal gadolinium powder are weighed according to the formula, and then ball milled, sieved, and dried in sequence to obtain a ceramic particle reinforced magnesium-based composite material;

[0010] (2) Model preprocessing: Use computer control software to perform three-dimensional modeling and layered slicing on the product in sequence to obtain the model and support files;

[0011] (3) Assembly: Load the ceramic particle reinforced magnesium-based composite material into the powder bin, install the magnesium alloy substrate and the scraper in the molding bin, and fill the printing bin with protective gas to ensure that the oxygen content is less than 100 ppm during the printing process;

[0012] (4) 3D printing: Import the model and support files into the laser selective melting forming equipment, set the printing parameters, and start spreading powder after the substrate reaches the preheating temperature. When the set powder thickness is reached, start printing.

[0013] The ball milling is performed intermittently under a protective atmosphere.

[0014] The process conditions of the ball milling are as follows: the ball-to-material ratio is (3-5):1, the rotation speed is 60-120 r / min, the total ball milling time is 2.5-3.5 h, the protective atmosphere is an inert gas, and the intermittent frequency is stirring for 25-30 min and then pausing for 8-10 min.

[0015] The sieved particle size is 15-53 μm.

[0016] The drying process conditions are as follows: temperature is 25-30°C and time is 2-3h.

[0017] The forming parameters in the printing parameters are consistent with the contour parameters; the forming parameter range is: laser power is 200-240W, scanning speed range is 100-120mm / s, scanning spacing is 0.04-0.08mm, and layer thickness is 0.05mm.

[0018] The preheating temperature is 190-215°C.

[0019] The invention discloses an application of a molding method of a ceramic particle reinforced magnesium-based composite material in the preparation of precision parts.

[0020] Beneficial effects:

[0021] The molding method of the present invention can significantly reduce the process steps, reduce labor costs, and improve the material strength, while solving the problem of ceramic particle agglomeration.

[0022] The material of the invention has excellent mechanical properties, and the ceramic particles are evenly distributed. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 The SEM images of the ball-milled ceramic particle reinforced magnesium-based composite powder in Example 1, wherein (a) the overall morphology of the powder; (b) the single spherical morphology of the powder;

[0024] Figure 2 This is the stress-strain curve of the molded product in Example 1. DETAILED DESCRIPTION

[0025] The specific embodiments of the present invention are further described in detail below, but the present invention is not limited to these embodiments, and any improvement or substitution based on the basic spirit of the present embodiment still falls within the scope of protection required by the claims of the present invention.

[0026] Example 1

[0027] A ceramic particle reinforced magnesium-based composite material comprises, in molar percentage, 9.0% Al, 0.5% Zn, 0.015% Mn, 0.01% Si, 0.001% Cu, 3% TiC, 3% Gd, and the balance Mg.

[0028] A method for forming a ceramic particle reinforced magnesium-based composite material comprises the following steps:

[0029] (1) Material pretreatment: After weighing magnesium powder, aluminum powder, zinc powder, manganese powder, silicon, copper powder, titanium carbide and gadolinium powder according to the formula, they were first intermittently ball milled for 2.5 h under an inert gas protective atmosphere at a ball-to-material ratio of 3:1 and a rotation speed of 60 r / min, and the mixture was paused for 8 min after each 25 min of stirring. The mixture was then sieved to obtain a powder of 15-53 μm, and finally dried at 25 °C for 2 h to obtain a ceramic particle reinforced magnesium-based composite material.

[0030] (2) Model preprocessing: Use UG modeling software to perform 3D modeling on the parts. After the 3D modeling is completed, export the 3D model in stl format. Then import the 3D model in stl format into Magics software. First, determine the arrangement of the parts. Then, add support and slice the model in layers to obtain the stl format model and support file with sliced ​​layers.

[0031] (3) Assembly: The ceramic particle reinforced magnesium matrix composite material is loaded into the powder bin, the magnesium alloy substrate and the scraper are installed in the molding bin, and the printing bin is filled with inert gas to ensure that the oxygen content is less than 100 ppm during the printing process;

[0032] (4) 3D printing: Import the sliced ​​stl format model and support file into the laser selective melting forming equipment, set the printing parameters, and start spreading powder after the substrate reaches 190°C. After reaching the set 0.05mm, start printing; the forming parameters in the printing parameters are consistent with the contour parameters; the forming parameter range is: laser power is 200W, scanning speed range is 100mm / s, scanning spacing is 0.04mm, and layer thickness is 0.05mm.

[0033] Example 2

[0034] A ceramic particle reinforced magnesium-based composite material comprises, in molar percentage, 9.5% Al, 0.9% Zn, 0.03% Mn, 0.03% Si, 0.01% Cu, 8% TiC, 5% Gd, and the balance Mg.

[0035] A method for forming a ceramic particle reinforced magnesium-based composite material comprises the following steps:

[0036] (1) Material pretreatment: After weighing magnesium powder, aluminum powder, zinc powder, manganese powder, silicon, copper powder, titanium carbide and gadolinium powder according to the formula, they were first intermittently ball milled for 3.5 hours under an inert gas protective atmosphere at a ball-to-material ratio of 5:1 and a rotation speed of 60 r / min, and the mixture was paused for 10 minutes after each stirring for 30 minutes. The mixture was then sieved to obtain a powder of 15-53 μm, and finally dried at 30°C for 3 hours to obtain a ceramic particle reinforced magnesium-based composite material.

[0037] (2) Model preprocessing: Use UG modeling software to perform 3D modeling on the parts. After the 3D modeling is completed, export the 3D model in stl format. Then import the 3D model in stl format into Magics software. First, determine the arrangement of the parts. Then, add support and slice the model in layers to obtain the stl format model and support file with sliced ​​layers.

[0038] (3) Assembly: The ceramic particle reinforced magnesium matrix composite material is loaded into the powder bin, the magnesium alloy substrate and the scraper are installed in the molding bin, and the printing bin is filled with inert gas to ensure that the oxygen content is less than 100 ppm during the printing process;

[0039] (4) 3D printing: Import the sliced ​​stl format model and support file into the laser selective melting forming equipment, set the printing parameters, and start spreading powder after the substrate reaches 215°C. After reaching the set 0.05mm, start printing; the forming parameters in the printing parameters are consistent with the contour parameters; the forming parameter range is: laser power is 240W, scanning speed range is 120mm / s, scanning spacing is 0.08mm, and layer thickness is 0.05mm.

[0040] Example 3

[0041] A ceramic particle reinforced magnesium-based composite material comprises, in molar percentage, 9.3% Al, 0.7% Zn, 0.021% Mn, 0.02% Si, 0.007% Cu, 5% TiC, 4% Gd, and the balance Mg.

[0042] A method for forming a ceramic particle reinforced magnesium-based composite material comprises the following steps:

[0043] (1) Material pretreatment: After weighing magnesium powder, aluminum powder, zinc powder, manganese powder, silicon, copper powder, titanium carbide and gadolinium powder according to the formula, they were first intermittently ball milled for 3 h under an inert gas protective atmosphere at a ball-to-material ratio of 4:1 and a rotation speed of 60 r / min, and the mixture was paused for 9 min after each stirring for 30 min. The mixture was then sieved to obtain a powder of 15-53 μm, and finally dried at 27°C for 2.5 h to obtain a ceramic particle reinforced magnesium-based composite material.

[0044] (2) Model preprocessing: Use UG modeling software to perform 3D modeling on the parts. After the 3D modeling is completed, export the 3D model in stl format. Then import the 3D model in stl format into Magics software. First, determine the arrangement of the parts. Then, add support and slice the model in layers to obtain the stl format model and support file with sliced ​​layers.

[0045] (3) Assembly: The ceramic particle reinforced magnesium matrix composite material is loaded into the powder bin, the magnesium alloy substrate and the scraper are installed in the molding bin, and the printing bin is filled with inert gas to ensure that the oxygen content is less than 100 ppm during the printing process;

[0046] (4) 3D printing: Import the sliced ​​stl format model and support file into the laser selective melting forming equipment, set the printing parameters, and start spreading powder after the substrate reaches 200°C. After reaching the set 0.05mm, start printing; the forming parameters in the printing parameters are consistent with the contour parameters; the forming parameter range is: laser power is 212W, scanning speed range is 110mm / s, scanning spacing is 0.05mm, and layer thickness is 0.05mm.

[0047] Depend on Figure 1 It can be seen that the microstructure of the ceramic particle reinforced magnesium-based composite material is a spherical structure, the powder surface is rough and particles of different sizes are distributed, indicating that the various element components are well combined and the elements in the powder are evenly and densely distributed.

[0048] The mechanical properties test results of the formed ceramic particle reinforced magnesium-based composite materials obtained in Examples 1-3 are shown in Table 1;

[0049] Table 1 Mechanical properties test results of various embodiments

[0050] sample Tensile strength(MPa) Yield strength(MPa) Elongation(%) Example 1 452 311 4.6 Example 2 446 309 5.2 Example 3 457 315 4.3

[0051] In the specific implementation process of the present invention, the magnesium alloy substrate is installed on the movable bottom plate in the forming chamber, and then the scraper is installed. During the installation process, the substrate and the scraper are ensured to be basically in a parallel state to ensure that a uniform and consistent powder layer can be obtained in the subsequent powder spreading process.

[0052] In the specific implementation process of the present invention, high-purity argon is used as the inert gas. When the printing chamber is filled with the inert gas, oxygen is also pumped out to ensure that the oxygen content in the printing chamber is less than 100ppm to prevent unexpected factors from occurring during the printing process.

[0053] In the specific implementation process of the present invention, the base is preheated and the preheating temperature is reasonably controlled, which can effectively reduce the residual stress level of the alloy, that is, reduce the risk of cracking.

Claims

1. A ceramic particle reinforced magnesium-based composite material, characterized in that: In mole percentage, it is: Al 9.0-9.5%, Zn 0.5-0.9%, Mn 0.015-0.03%, Si 0.01-0.03%, Cu 0.001-0.01%, TiC 3-8%, Gd 3-5%, and the balance is Mg.

2. The method for forming a ceramic particle reinforced magnesium-based composite material according to claim 1, characterized in that: The steps include: (1) Material pretreatment: magnesium powder, aluminum powder, zinc powder, manganese powder, elemental silicon, copper powder, titanium carbide, and metal gadolinium powder are weighed according to the formula, and then ball milled, sieved, and dried in sequence to obtain a ceramic particle reinforced magnesium-based composite material; (2) Model preprocessing: Use computer control software to perform three-dimensional modeling and layered slicing on the product in sequence to obtain the model and support files; (3) Assembly: Load the ceramic particle reinforced magnesium-based composite material into the powder bin, install the magnesium alloy substrate and the scraper in the molding bin, and fill the printing bin with protective gas to ensure that the oxygen content is less than 100 ppm during the printing process; (4) 3D printing: Import the model and support files into the laser selective melting forming equipment, set the printing parameters, and start spreading powder after the substrate reaches the preheating temperature. When the set powder thickness is reached, start printing.

3. The method for forming a ceramic particle reinforced magnesium-based composite material according to claim 2, characterized in that: The ball milling is performed intermittently under a protective atmosphere.

4. The method for forming a ceramic particle reinforced magnesium-based composite material according to claim 2, characterized in that: The process conditions of the ball milling are as follows: the ball-to-material ratio is (3-5):1, the rotation speed is 60-120 r / min, the total ball milling time is 2.5-3.5 h, the protective atmosphere is an inert gas, and the intermittent frequency is stirring for 25-30 min and then pausing for 8-10 min.

5. The method for forming a ceramic particle reinforced magnesium-based composite material according to claim 2, characterized in that: The sieved particle size is 15-53 μm.

6. The method for forming a ceramic particle reinforced magnesium-based composite material according to claim 2, characterized in that: The drying process conditions are as follows: temperature is 25-30°C and time is 2-3h.

7. The method for forming a ceramic particle reinforced magnesium-based composite material according to claim 2, characterized in that: The forming parameters in the printing parameters are consistent with the contour parameters; the forming parameter range is: laser power is 200-240W, scanning speed range is 100-120mm / s, scanning spacing is 0.04-0.08mm, and layer thickness is 0.05mm.

8. The method for forming a ceramic particle reinforced magnesium-based composite material according to claim 2, characterized in that: The preheating temperature is 190-215°C.

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