3D printing manufacturing method of metal molybdenum and application of 3D printing manufacturing method of metal molybdenum in manufacturing of biomedical equipment

Abstract

The invention discloses a 3D printing manufacturing method of metal molybdenum and application of the 3D printing manufacturing method of the metal molybdenum in manufacturing of biological medical equipment. The 3D printing manufacturing method of the metal molybdenum comprises the steps that spherical molybdenum powder is loaded into 3D printing equipment for 3D printing manufacturing forming, the scanning power of 3D printing is 380-420 W, the scanning speed is 500-800 mm / s, the scanning layer thickness is 20-40 microns, the scanning interval is 70-100 microns, and the laser energy density is 118-280 J / mm < 3 >. The spherical molybdenum powder is used as the raw material, and metal molybdenum with high density, tensile strength sigma b, yield strength sigma 0.2 and elasticity modulus can be prepared by adopting a proper 3D printing forming process.

Description

Technical Field

[0001] The present invention relates to the field of additive manufacturing technology, and in particular to a 3D printing manufacturing method for metal molybdenum and an application of the 3D printing manufacturing method for metal molybdenum in manufacturing biomedical equipment. Background Art

[0002] Refractory metal molybdenum has the characteristics of high melting point, excellent high-temperature mechanical properties, good thermal conductivity, etc., and its good resistance to radiation swelling and compatibility with liquid metal make it an important candidate material for advanced nuclear reactors such as the fourth-generation high-temperature nuclear fission reactor and fusion reactor, which can meet the preparation requirements of structural parts in harsh environments such as high temperature, strong corrosion, and high-dose radiation. However, many factors such as its high deformation temperature, poor low-temperature plasticity, and severe high-temperature oxidation bring many difficulties to traditional preparation and processing technologies.

[0003] Metallic molybdenum is usually produced by powder metallurgy, but powder metallurgy has limitations in manufacturing complex geometric shapes and small batch parts. In view of this, the present invention is proposed. Summary of the invention

[0004] The purpose of the present invention is to provide a 3D printing manufacturing method for metal molybdenum and the application of the 3D printing manufacturing method for metal molybdenum in the manufacture of biomedical devices, and to provide a method for easily manufacturing complex geometric shapes and small batches of metal molybdenum parts.

[0005] The present invention is achieved in that:

[0006] In the first aspect, the present invention provides a 3D printing manufacturing method for metallic molybdenum, comprising: loading spherical molybdenum powder into a 3D printing device for 3D printing and manufacturing, the scanning power of 3D printing is 380-420W, the scanning speed is 500-800mm / s, the scanning layer thickness is 20-40μm, the scanning spacing is 70-100μm, and the laser energy density is 118-280J / mm 3 .

[0007] In an optional embodiment, the scanning power is 380-420 W, the scanning speed is 500-800 mm / s, the scanning layer thickness is 40 μm, the scanning interval is 80-100 μm, and the laser energy density is 218.75-262.5 J / mm 3 .

[0008] In an optional embodiment, the scanning layer angle is 66-68°.

[0009] In an optional embodiment, the 3D printed substrate is TC4 titanium alloy.

[0010] In an optional embodiment, the 3D printing forming equipment is first purged with high-purity argon gas until the oxygen content in the forming equipment is less than 100 ppm, and then 3D printing and manufacturing are performed.

[0011] In an optional embodiment, the average particle size of the spherical molybdenum powder is 19.15-54.89 μm.

[0012] In an optional embodiment, the method for preparing the spherical molybdenum powder comprises: spheroidizing dry molybdenum powder having a particle size less than 200 meshes using a radio frequency plasma spheroidizing device.

[0013] In an optional embodiment, the spheroidization comprises:

[0014] Establish a stable operation of argon or argon / helium plasma torch, where the RF induction coil is loaded with a voltage of 6 to 8 kV;

[0015] The dry molybdenum powder with a particle size less than 200 mesh is injected into the high temperature zone at the center of the plasma torch by using a carrying gas for heating. The heating time is 100 to 200 ms. 3 ~10 6 K / m cooling rate to form spherical molybdenum powder.

[0016] In an optional embodiment, the preparation of the dry molybdenum powder includes: placing the molybdenum powder obtained by spray granulation in a vacuum drying oven for vacuum drying for 2 to 4 hours at a drying temperature of 80 to 150° C., and sieving after drying to obtain dry molybdenum powder with a particle size of less than 200 mesh.

[0017] In a second aspect, the present invention provides an application of the 3D printing manufacturing method of metal molybdenum described in any one of the aforementioned embodiments in the manufacture of biomedical devices.

[0018] The present invention has the following beneficial effects:

[0019] The present invention uses spherical molybdenum powder as raw material and adopts a suitable 3D printing forming process to prepare a spherical molybdenum powder with high density and tensile strength. b , yield strength σ 0.2 Metal molybdenum has high elastic modulus and can meet the performance index requirements of nuclear reactor structural materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0021] Figure 1 The morphology of the radio frequency plasma spheroidized molybdenum powder selected in Example 1 of the present invention;

[0022] Figure 2 The particle size and distribution of the radio frequency plasma spheroidized molybdenum powder selected in Example 1 of the present invention;

[0023] Figure 3 This is the test result of the impurity content of the RF plasma spheroidized molybdenum powder selected in Example 1 of the present invention. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the technical scheme in the embodiments of the present invention will be described clearly and completely below. If the specific conditions are not specified in the embodiments, they are carried out according to conventional conditions or conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be purchased commercially.

[0025] The present invention provides a 3D printing manufacturing method for metal molybdenum, comprising: loading spherical molybdenum powder into a 3D printing device for 3D printing manufacturing, wherein the scanning power of the 3D printing is 380-420W, the scanning speed is 500-800mm / s, the scanning layer thickness is 20-40μm, the scanning interval is 70-100μm, and the laser energy density is 118-280J / mm 3 .

[0026] The present invention uses spherical molybdenum powder as raw material and adopts a suitable 3D printing forming process to prepare a spherical molybdenum powder with high density and tensile strength. b , yield strength σ 0.2 , and metal molybdenum products with high elastic modulus.

[0027] Specifically, in an optional embodiment, the scanning power of 3D printing is 380-420W, for example, 380, 390, 400, 410, 420W or any value between 380 and 420W; the scanning speed is 500-800mm / s, for example, 500, 600, 700, 800mm / s or any value between 500 and 800mm / s; the scanning layer thickness is 20-40μm, for example, 20, 25, 30, 35, 40μm or any value between 20 and 40μm; the scanning spacing is 70-100μm, for example, 70, 80, 90, 100μm or any value between 70 and 100μm; the laser energy density is 118-280J / mm 3 , for example 150, 180, 210, 240, 271.431 J / mm 3 or 118~280J / mm 3 Any value in between.

[0028] In an optional embodiment, the scanning power is 380-420 W, the scanning speed is 500-800 mm / s, the scanning layer thickness is 40 μm, the scanning interval is 80-100 μm, and the laser energy density is 218.75-262.5 J / mm 3 .

[0029] In an optional embodiment, the scanning layer angle is 66-68°, such as 66, 66.5, 67, 67.5, 68° or any value between 66-68°.

[0030] In an optional embodiment, the 3D printed substrate is TC4 titanium alloy.

[0031] In an optional embodiment, the 3D printing forming equipment is first purged with high-purity argon gas until the oxygen content in the forming equipment is less than 100 ppm, and then 3D printing and manufacturing are performed.

[0032] In an optional embodiment, the average particle size of the spherical molybdenum powder is 19.15-54.89 μm.

[0033] In an optional embodiment, the method for preparing the spherical molybdenum powder comprises: spheroidizing dry molybdenum powder having a particle size less than 200 meshes using a radio frequency plasma spheroidizing device.

[0034] In an optional embodiment, the spheroidization comprises:

[0035] Establish a stable operation of argon or argon / helium plasma torch, where the RF induction coil is loaded with a voltage of 6 to 8 kV;

[0036] The dry molybdenum powder with a particle size less than 200 mesh is injected into the high temperature zone at the center of the plasma torch by using a carrying gas for heating. The heating time is 100 to 200 ms. 3 ~10 6 K / m cooling rate to form spherical molybdenum powder.

[0037] The spray-granulated molybdenum powder is injected into the high-temperature zone in the center of the plasma torch by using a carrier gas for heating. The carrier gas can be argon or other gases that do not react chemically with metal powders in a high-temperature environment. The heating time ends when the gas / powder flow "flies away" from the plasma torch, and lasts for about 100 to 200 milliseconds. The spray-granulated molybdenum powder is sent into the high-temperature zone in the center of the plasma torch. Under the action of four heat transfer mechanisms: radiation, convection, conduction, and chemistry, a large amount of heat is absorbed. The surface of the particles is rapidly heated and melted. When more than 50% of the weight of the particles is melted, the molten particles form highly spherical droplets under the action of surface tension, and are rapidly cooled under extremely high temperature gradients to form spherical particles. Among them, the temperature gradient is 10 3 ~106 K / m.

[0038] After the spheroidization process is completed, the gas is extracted, processed and discharged, and the spheroidized particles enter the collection tank.

[0039] The invention uses spray granulated molybdenum powder as raw material and adopts radio frequency plasma spheroidization powder making technology to prepare spherical molybdenum powder. The spherical molybdenum powder has regular shape, high purity and excellent flowability.

[0040] In an optional embodiment, the preparation of the dry molybdenum powder includes: placing the molybdenum powder obtained by spray granulation in a vacuum drying oven for vacuum drying for 2 to 4 hours at a drying temperature of 80 to 150° C., and sieving after drying to obtain dry molybdenum powder with a particle size of less than 200 mesh.

[0041] An embodiment of the present invention also provides an application of the 3D printing manufacturing method of metal molybdenum described in any one of the aforementioned embodiments in the manufacture of biomedical devices.

[0042] The features and performance of the present invention are further described in detail below in conjunction with the embodiments.

[0043] Example 1

[0044] This embodiment provides a 3D printing manufacturing method for metal molybdenum, comprising:

[0045] 1. Prepare spherical molybdenum powder for 3D printing.

[0046] The molybdenum powder obtained by spray granulation is placed in a vacuum drying oven for vacuum drying for 3 hours at a drying temperature of 80 to 150°C.

[0047] The dried powder was sieved by a 200-mesh manual sieving machine, and the sieved material was taken to obtain spray-granulated molybdenum powder, which was then put into a powder feeding system of a radio frequency plasma spheroidization device.

[0048] Establish a stable argon plasma torch. A certain amount of argon gas is continuously fed into the plasma reactor, and the RF induction coil is loaded with a high voltage of 7KV. At the same time, an arc discharge is initiated to ionize the argon gas and generate an argon plasma torch. At this time, the entire plasma reactor is kept in a normal balance of 3.6slpm to ensure the stable operation of the plasma torch.

[0049] The irregular molybdenum powder is injected into the high temperature zone in the center of the plasma torch using argon as a carrier gas for heating. The heating time ends when the gas / powder flow "flies away" from the plasma torch. The heating duration is about 100 to 200 milliseconds. When more than 50% of the particle weight is melted, the molten particles form highly spherical droplets under the action of surface tension and melt under the extremely high temperature gradient of 10 6 K / m, thereby forming spherical particles.

[0050] The gas was extracted and the spherical molybdenum powder was collected. The electron microscope image is as follows Figure 1 The particle size distribution diagram is shown in Figure 2 As shown, the impurity content is Figure 3 As shown in the figure, the prepared molybdenum powder has a regular morphology, is spherical, and has a relatively concentrated particle size distribution.

[0051] 2. 3D printing of metal molybdenum.

[0052] Select a TC4 titanium alloy substrate and install it. Load the collected 19.15-54.89μm spherical molybdenum powder into the red light 3D printing equipment. Use high-purity argon gas to purge the 3D printing forming equipment until the oxygen content in the forming equipment is less than 100ppm.

[0053] The 3D printing program is set according to the process window to perform 3D printing of metal molybdenum, and finally the 3D printed metal molybdenum of the present invention is obtained. The 3D printing process includes: scanning layer angle of 67°, scanning power of 380W, scanning speed of 500mm / s, scanning layer thickness of 40μm, and scanning spacing of 70μm. Laser energy density 271.43J / mm 3 . Carry out selective laser melting 3D printing and finally obtain 3D printed metal molybdenum.

[0054] Example 2

[0055] This embodiment provides a 3D printing manufacturing method for metal molybdenum, which is different from Embodiment 1 in that:

[0056] Scanning power 380W, scanning speed 600mm / s, scanning spacing 80μm, laser energy density 197.92J / mm 3 The other aspects are the same as those in Example 1, and selective laser melting 3D printing is carried out to finally obtain 3D printed metal molybdenum, as shown in Table 1.

[0057] Example 3

[0058] This embodiment provides a 3D printing manufacturing method for metal molybdenum, which is different from Embodiment 1 in that:

[0059] Scanning power 380W, scanning speed 700mm / s, scanning spacing 90μm, laser energy density 150.79J / mm 3 The other aspects are the same as those in Example 1, and selective laser melting 3D printing is carried out to finally obtain 3D printed metal molybdenum, as shown in Table 1.

[0060] Example 4

[0061] This embodiment provides a 3D printing manufacturing method for metal molybdenum, which is different from Embodiment 1 in that:

[0062] Scanning power 380W, scanning speed 800mm / s, scanning spacing 100μm, laser energy density 118.75J / mm 3 The other aspects are the same as those in Example 1, and selective laser melting 3D printing is carried out to finally obtain 3D printed metal molybdenum, as shown in Table 1.

[0063] Example 5

[0064] This embodiment provides a 3D printing manufacturing method for metal molybdenum, which is different from Embodiment 1 in that:

[0065] Scanning power 420W, scanning speed 800mm / s, scanning spacing 80μm, laser energy density 262.5J / mm 3 The other aspects are the same as those in Example 1, and selective laser melting 3D printing is carried out to finally obtain 3D printed metal molybdenum, as shown in Table 1.

[0066] Example 6

[0067] This embodiment provides a 3D printing manufacturing method for metal molybdenum, which is different from Embodiment 1 in that:

[0068] Scanning power 420W, scanning 500mm / s, scanning spacing 90μm, laser energy density 233.3J / mm 3 The other aspects are the same as those in Example 1, and selective laser melting 3D printing is carried out to finally obtain 3D printed metal molybdenum, as shown in Table 1.

[0069] Comparative Example 1

[0070] The difference between this comparative example and Example 5 is that, in an optional embodiment, the laser power and the scanning speed are different, the scanning power is 350W, the scanning is 400mm / s, the scanning spacing is 70μm, and the laser energy density is 312.5J / mm 3 , the rest is the same as in Example 5, and selective laser melting 3D printing is carried out to finally obtain 3D printed metal molybdenum, as shown in Table 1.

[0071] Comparative Example 2

[0072] The difference between this comparative example and Example 5 is that, in an optional embodiment, the laser power and the scanning speed are different, the scanning power is 450W, the scanning is 900mm / s, the scanning spacing is 70μm, and the laser energy density is 178.57J / mm 3 , the rest is the same as in Example 5, and selective laser melting 3D printing is carried out to finally obtain 3D printed metal molybdenum, as shown in Table 1.

[0073] Comparative Example 3

[0074] The difference between this comparative example and Example 5 is that a green light 3D printing device is used for 3D printing, with a scanning power of 350W, a scanning speed of 400mm / s, a scanning spacing of 70μm, and a laser energy density of 312.5J / mm 3 , the rest is the same as in Example 5, and selective laser melting 3D printing is carried out to finally obtain 3D printed metal molybdenum, as shown in Table 1.

[0075] Comparative Example 4

[0076] The difference between this comparative example and Example 5 is that the green light 3D printing equipment is used for 3D printing, the scanning power is 380W, the scanning speed is 800mm / s, the scanning interval is 100μm, and the laser energy density is 118.75J / mm 3 , the rest is the same as in Example 5, and selective laser melting 3D printing is carried out to finally obtain 3D printed metal molybdenum, as shown in Table 1.

[0077] Comparative Example 5

[0078] The only difference between this comparative example and Example 5 is that a green light 3D printing device is used for 3D printing, the process parameters are the same as those in Example 5, and selective laser melting 3D printing is carried out to finally obtain 3D printed metal molybdenum, as shown in Table 1.

[0079] Comparative Example 6

[0080] The difference between this comparative example and Example 5 is that a green light 3D printing device is used for 3D printing, with a scanning power of 450W, a scanning speed of 900mm / s, a scanning interval of 70μm, and a laser energy density of 178.57J / mm 3 , the rest is the same as in Example 5, and selective laser melting 3D printing is carried out to finally obtain 3D printed metal molybdenum, as shown in Table 1.

[0081] The metal molybdenum samples prepared in the above embodiments and comparative examples were tested, wherein the density of the metal molybdenum samples was determined by the water displacement method; and the tensile properties of the metal molybdenum were determined by a universal tensile testing machine and other devices. The test results are shown in Table 1.

[0082] Table 1

[0083]

[0084]

[0085] It can be seen from Table 1 that the density of 3D printed metal molybdenum in Examples 1 to 6 of the present invention varies with different 3D printing process parameters, and the density values ​​are distributed in the range of 95.25% to 99.78%.

[0086] It can be seen from Table 1 that in the present invention, when the 3D printing process parameters are set within the above-mentioned required range, metal molybdenum with high density, tensile strength, yield strength and elastic modulus that can meet the performance index requirements of nuclear reactor structural materials can be obtained. By comparing Example 5 with the comparative example, it can be seen that when any parameters of the 3D printing process exceed the above-mentioned range, the performance of the metal molybdenum sample will be reduced.

[0087] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A 3D printing method for manufacturing metal molybdenum, characterized in that: include: The spherical molybdenum powder is loaded into the 3D printing equipment for 3D printing and molding. The scanning power of 3D printing is 380-420W, the scanning speed is 500-800mm / s, the scanning layer thickness is 20-40μm, the scanning interval is 70-100μm, and the laser energy density is 118-280J / mm 3 .

2. The 3D printing manufacturing method of metal molybdenum according to claim 1, characterized in that: Scanning power is 380-420W, scanning speed is 500-800mm / s, scanning layer thickness is 40μm, scanning interval is 80-100μm, laser energy density is 118.75-262.5J / mm 3 .

3. The 3D printing manufacturing method of metal molybdenum according to claim 1, characterized in that: The scanning inter-layer angle is 66-68°.

4. The 3D printing manufacturing method of metal molybdenum according to claim 1, characterized in that: The 3D printed substrate is TC4 titanium alloy.

5. The 3D printing manufacturing method of metal molybdenum according to claim 1, characterized in that: First, use high-purity argon gas to purge the 3D printing forming equipment. After the oxygen content in the forming equipment is purged to less than 100ppm, 3D printing and manufacturing can be carried out.

6. The 3D printing manufacturing method of metal molybdenum according to claim 1, characterized in that: The average particle size of the spherical molybdenum powder is 19.15-54.89 μm.

7. The 3D printing manufacturing method of metal molybdenum according to claim 1, characterized in that: The preparation method of the spherical molybdenum powder comprises: spheroidizing the dry molybdenum powder with a particle size less than 200 meshes by using radio frequency plasma spheroidizing equipment.

8. The 3D printing manufacturing method of metal molybdenum according to claim 7, characterized in that: The spheroidization comprises: Establish a stable operation of argon or argon / helium plasma torch, where the RF induction coil is loaded with a voltage of 6 to 8 kV; The dry molybdenum powder with a particle size less than 200 mesh is injected into the high temperature zone at the center of the plasma torch by using a carrying gas for heating. The heating time is 100 to 200 ms. 3 ~10 6 K / m cooling rate to form spherical molybdenum powder.

9. The 3D printing manufacturing method of metal molybdenum according to claim 1, characterized in that: The preparation of the dry molybdenum powder comprises: placing the molybdenum powder obtained by spray granulation in a vacuum drying oven for 2 to 4 hours at a drying temperature of 80 to 150° C., and sieving after drying to obtain dry molybdenum powder with a particle size less than 200 meshes.

10. Application of the 3D printing manufacturing method of metallic molybdenum according to any one of claims 1 to 9 in the manufacture of biomedical devices.

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