阅读说明：本技术 一种基于激光选区熔化技术制备钽件的方法 (Method for preparing tantalum piece based on selective laser melting technology ) 是由 郑泽锦 刘杰 陈敏生 朱涛 亢志颖 于 2021-01-12 设计创作，主要内容包括：本发明提供了一种基于激光选区熔化技术制备钽件的方法,所述方法包括将钽金属粉末放置于SLM设备的送粉缸内；使用三维设计软件构建目标打印样件的模型,然后导入切片软件中进行二维切片处理,切片处理过程中对打印工艺参数的设定,再将文件导入SLM设备中,进行打印,得到钽件。本发明通过优化制备钽件的工艺参数,并采用均匀且高球形度、低含氧量以及低反光率的钽金属粉末作为钽件制备的原材料,能获得密度为99.2073％-99.8852％的高致密钽件,满足其使用要求,同时,有助于获得效果显著的抗拉强度、屈服强度以及延伸率,并能获得精度较高的钽件。(The invention provides a method for preparing a tantalum piece based on a selective laser melting technology, which comprises the steps of placing tantalum metal powder in a powder feeding cylinder of SLM equipment; and constructing a model of the target printing sample piece by using three-dimensional design software, then introducing the model into slicing software for two-dimensional slicing processing, setting printing process parameters in the slicing processing process, and then introducing the file into SLM equipment for printing to obtain the tantalum piece. According to the method, the technological parameters for preparing the tantalum piece are optimized, and the uniform tantalum metal powder with high sphericity, low oxygen content and low light reflection rate is used as the raw material for preparing the tantalum piece, so that the high-density tantalum piece with the density of 99.2073-99.8852% can be obtained, the use requirement of the high-density tantalum piece is met, meanwhile, the high-density tantalum piece with remarkable effects on tensile strength, yield strength and elongation rate can be obtained, and the high-precision tantalum piece can be obtained.)

1. A method for preparing a tantalum piece based on a selective laser melting technology is characterized by comprising the following steps:

placing tantalum metal powder in a powder feeding cylinder of SLM equipment;

constructing a model of a target printing sample by using three-dimensional design software, then introducing the model into slicing software for two-dimensional slicing, setting printing process parameters in the slicing process, introducing a file into SLM (selective laser melting) equipment for printing to obtain a tantalum piece;

wherein the tantalum metal powder comprises the following components in percentage by mass: 0.001% of C, 0.004-0.006% of N, 0.0012-0.0016% of H, 0.0025-0.0030% of Nb, 0.0015-0.0055% of Fe, 0.001% of Ti, 0.0045-0.0060% of W, 0.001-0.005% of Mo, 0.0002-0.0006% of Si, 0.001-0.003% of Ni and the balance of Ta.

2. The method of claim 1, wherein the tantalum metal powder has an oxygen content of 120ppm to 150 ppm.

3. The method of claim 2, wherein the tantalum metal powder has a spherical structure.

4. The method of claim 3, wherein said tantalum metal powder has a flowability of 4.5s/50g-5.5s/50g and a bulk density of 9.94g/cm³The tap density of the tantalum metal powder is 10.7g/cm³。

5. The method for preparing tantalum piece based on selective laser melting technology of claim 1, wherein the powder layer in the printing process parameters is 20-40 μm thick, the power is 280-400W, and the laser energy density is 100J/mm³-300J/mm³The scanning distance is 0.07mm-0.09 mm.

6. The method for preparing tantalum pieces based on the selective laser melting technology as claimed in claim 5, wherein the SLM device comprises a forming cavity, a gas supply device, a dust purification device, a forming cylinder, a powder feeding cylinder and a powder spreading device, wherein the gas supply device, the dust purification device, the forming cylinder and the powder feeding cylinder are respectively communicated with the forming cavity, the powder spreading device is arranged in the forming cavity and can reciprocate along the width direction of the forming cavity, and the forming cylinder and the powder feeding cylinder are arranged at the bottom of the forming cavity and are integrally formed with the forming cavity.

7. The method of claim 6, wherein during said printing, said forming chamber is evacuated to a vacuum and argon is introduced into said forming chamber via said gas supply means such that the oxygen content in said forming chamber is less than 100 ppm.

8. The method of claim 6, wherein a first piston and a base plate are disposed within the forming cylinder, and the base plate is connected to the first piston.

9. The method of claim 8, wherein the pre-heating temperature of the substrate during the printing is set to 180 ℃ to 220 ℃.

10. The method of claim 5, wherein the tantalum article has a densification of from 99.2073% to 99.8852%.

Technical Field

The invention relates to the field of tantalum piece preparation, in particular to a method for preparing a tantalum piece based on a selective laser melting technology.

Background

Tantalum and tantalum alloys belong to refractory metals, have special dielectric properties, low plastic-brittle transition temperature, exceptional corrosion resistance, and are well-known metal materials with optimal biocompatibility. Tantalum and tantalum alloys are widely used in the fields of electronics, aerospace, high temperature superconduction, and atomic energy industry, and high-end bioimplants made of tantalum have been widely used in the field of medical implants. Because the melting point of the metal Ta reaches about 3000 ℃, and the density reaches 16.65g/cm3, the target tantalum metal part prepared by the additive manufacturing process has fine crystal grains and uniform structural components, and can effectively solve the problems of coarse crystalline structure, easy internal porosity and component segregation of the traditional cast tantalum and tantalum alloy materials. In the prior art, a selective laser sintering technology and a selective laser melting technology are adopted to prepare a tantalum part, but the selective laser sintering technology adopts a semi-solid liquid phase sintering mechanism, so that the tantalum powder material is incompletely melted, and although the thermal stress accumulated by a formed material can be reduced to a certain extent, the formed part contains particles of an unmelted phase, so that the process defects of high porosity, low density, poor tensile strength, high surface roughness and the like are directly caused. Meanwhile, because the strength of the sintered metal tantalum part is low, the high strength can be achieved only by post-treatment, and the manufacturing cost and the processing efficiency are greatly increased. The SLM equipment is utilized to print the sample, research parameters mainly discuss laser energy density caused by laser power and laser scanning speed change, density and defect analysis is carried out on the formed sample, and the tested sample has low relative density and cannot meet the requirement of the density of the tantalum metal formed part in the expectation.

In summary, there still exist technical problems to be solved in the technical field of tantalum device preparation.

Disclosure of Invention

Based on the above, in order to solve the problems that the density of the prepared tantalum piece does not meet the use requirement and the relative density of the prepared tantalum piece is low in the prior art, the invention provides a method for preparing the tantalum piece based on a selective laser melting technology, which has the following specific technical scheme:

a method for preparing a tantalum piece based on a selective laser melting technology comprises the following steps:

placing tantalum metal powder in a powder feeding cylinder of SLM equipment;

constructing a model of a target printing sample by using three-dimensional design software, storing the model in an STL format, then introducing the model into slicing software for two-dimensional slicing, setting printing process parameters in the slicing process, introducing a file into SLM equipment, and printing to obtain a tantalum piece;

wherein the tantalum metal powder comprises the following components in percentage by mass: 0.001% of C, 0.004-0.006% of N, 0.0012-0.0016% of H, 0.0025-0.0030% of Nb, 0.0015-0.0055% of Fe, 0.001% of Ti, 0.0045-0.0060% of W, 0.001-0.005% of Mo, 0.0002-0.0006% of Si, 0.001-0.003% of Ni and the balance of Ta.

Preferably, the tantalum metal powder has an oxygen content of 120ppm to 150 ppm.

Preferably, the tantalum metal powder has a spherical structure.

Preferably, the tantalum metal powder has a flowability of 4.5s/50g to 5.5s/50g and a bulk density of 9.94g/cm³The tap density of the tantalum metal powder is 10.7g/cm³。

Preferably, the thickness of the powder spreading layer in the printing process parameters is 20-40 μm, the power is 280-400W, and the laser energy density is 100J/mm³-300J/mm³The scanning distance is 0.07mm-0.09 mm.

Preferably, SLM equipment includes becomes die cavity, air feeder, dust purification device, shaping jar, send whitewashed jar and shop's powder device, the air feeder dust purification device the shaping jar and send whitewashed jar respectively with become the die cavity intercommunication, shop's powder device sets up in the shaping intracavity and can along reciprocating motion is to the width direction that becomes the die cavity, just the shaping jar and send whitewashed jar setting to be in the bottom that becomes the die cavity and with become die cavity integrated into one piece.

Preferably, in the printing process, the molding cavity is firstly evacuated to a vacuum state, and then argon is input into the molding cavity through the gas supply device, so that the oxygen content in the molding cavity is less than 100 ppm.

Preferably, a first piston and a base plate are arranged in the forming cylinder, and the base plate is connected with the first piston.

Preferably, the preheating temperature of the substrate is set to 180-220 ℃ during printing.

Preferably, the density of the tantalum piece is 99.2073% -99.8852%.

According to the scheme, by optimizing the technological parameters for preparing the tantalum piece and adopting uniform tantalum metal powder with high sphericity, low oxygen content and low light reflection rate as the raw material for preparing the tantalum piece, the high-density tantalum piece with the density of 99.2073-99.8852% can be obtained, the use requirement of the high-density tantalum piece is met, and meanwhile, the high-density tantalum piece with excellent tensile strength, yield strength, elongation and high precision is favorably obtained.

Drawings

FIG. 1 is a schematic diagram of a microscopic electron microscope of tantalum metal powder in a method for preparing a tantalum piece based on a selective laser melting technology according to the present invention;

FIG. 2 is a schematic illustration of the particle size distribution of tantalum metal powder in a method of producing a tantalum part based on a selective laser melting technique according to the present invention;

FIG. 3 is a schematic microstructural representation of a tantalum piece prepared in example 4 of the invention;

FIG. 4 is a schematic microstructural representation of a tantalum piece prepared in example 8 of the present invention;

FIG. 5 is a schematic diagram of an SLM device in a method for manufacturing tantalum pieces based on a selective laser melting technique according to the present invention;

FIG. 6 is a schematic diagram of a tantalum part prepared based on a selective laser melting technique according to the present invention.

Description of reference numerals:

1-forming a cavity; 2-a gas supply device; 3-a dust purification device; 4-forming a cylinder; 5-powder feeding cylinder; 6-a powder spreading device; 7-a first piston; 8-a substrate; 9-an industrial personal computer; 10-fiber laser; 11-optical path means; 12-second piston.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to embodiments thereof. It should be understood that the detailed description and specific examples, while indicating the scope of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

In one embodiment of the invention, a method for preparing a tantalum piece based on a selective laser melting technology comprises the following steps:

placing tantalum metal powder in a powder feeding cylinder of SLM equipment;

establishing a model of a target printing sample by using three-dimensional design software, then importing the model into slicing software for two-dimensional slicing, setting printing process parameters in the slicing process, importing a file into SLM equipment, and printing;

wherein the tantalum metal powder comprises the following components in percentage by mass: 0.001% of C, 0.004-0.006% of N, 0.0012-0.0016% of H, 0.0025-0.0030% of Nb, 0.0015-0.0055% of Fe, 0.001% of Ti, 0.0045-0.0060% of W, 0.001-0.005% of Mo, 0.0002-0.0006% of Si, 0.001-0.003% of Ni and the balance of Ta.

In one embodiment, the tantalum metal powder has an oxygen content of 120ppm to 150 ppm.

In one embodiment, the tantalum metal powder has a spherical structure.

In one embodiment, the tantalum metal powder has a flowability of 4.5s/50g to 5.5s/50g and a bulk density of 9.94g/cm³The tap density of the tantalum metal powder is 10.7g/cm³。

In one embodiment, the tantalum metal powder has a grain size of 15-45 μm, which accounts for more than 90% by mass of the tantalum metal powder; the tantalum metal powder comprises particles with the particle size larger than 63 mu m, and the mass percentage of the particles in the tantalum metal powder is less than or equal to 3%. As shown in fig. 1 and 2, the tantalum metal powder of the present invention is generally uniform, ensuring smooth and uniform dispersion of particles during the powder spreading process, so that the tantalum metal powder is more suitable for SLM forming.

In one embodiment, the Ta comprises greater than 99.9% by weight of the tantalum metal powder.

In one embodiment, the powder spreading layer in the printing process parameters is 20-40 μm thick, the power is 280-400W, and the laser energy density is 100J/mm³-300J/mm³The laser scanning interval is 0.07mm-0.09 mm.

In one embodiment, the laser scan rate in the printing process parameters is 420mm/s-1250 mm/s.

In one of them embodiment, the SLM equipment includes shaping chamber 1, air feeder 2, dust purification device 3, shaping jar 4, powder feeding jar 5 and shop's powder device 6, air feeder 2 dust purification device 3 shaping jar 4 and powder feeding jar 5 respectively with shaping chamber 1 intercommunication, shop's powder device 6 sets up in shaping chamber 1 and can along reciprocating motion is to the width direction in shaping chamber 1, shaping jar 4 and powder feeding jar 5 sets up the bottom in shaping chamber 1 and with shaping chamber 1 integrated into one piece is specifically as shown in fig. 5.

In one embodiment, during the printing process, the forming cavity 1 is first evacuated to a vacuum state, and then argon gas is input into the forming cavity 1 through the gas supply device, so that the oxygen content in the forming cavity is less than 100 ppm.

In one embodiment, a first piston 7 and a base plate 8 are arranged in the forming cylinder 4, and the base plate 8 is connected with the first piston 7.

In one embodiment, the pre-heating temperature of the substrate 8 is set to 180-220 ℃ during the printing.

In one embodiment, the compactness of the tantalum piece is 99.2073-99.8852%.

In the scheme, by optimizing the technological parameters for preparing the tantalum piece and adopting uniform tantalum metal powder with high sphericity, low oxygen content and low light reflection rate as the raw material for preparing the tantalum piece, the tantalum piece with the density of 99.2073-99.8852% can be obtained, the use requirement of the tantalum piece is met, meanwhile, the method is favorable for obtaining the tensile strength, the yield strength and the elongation rate with remarkable effects, and the tantalum piece with higher precision can be obtained.

In one embodiment, a second piston 12 is arranged in the powder feeding cylinder 5.

In one embodiment, the SLM device further includes an industrial personal computer 9, a fiber laser 10, and an optical path device 11, and the gas supply device 2, the dust purification device 3, the powder spreading device 6, the first piston 7, the second piston 12, and the fiber laser 10 are respectively connected to the industrial personal computer 9. The industrial personal computer 9 is used for controlling the gas supply device 2, the dust purification device 3, the powder spreading device 6, the first piston 7, the second piston 12 and the optical fiber laser 10.

In one embodiment, the first piston 7 is movable away from the mold cavity 1 and the second piston 12 is movable towards the mold cavity 1. When the second piston 12 moves towards the direction close to the molding cavity 1, the tantalum metal powder placed in the powder feeding cylinder 5 can be pushed to the molding cavity 1, then the tantalum metal powder is pushed to the molding cylinder 4 through the powder laying device 6, and finally laser scanning is provided through the light path device 11 to obtain a tantalum piece through printing.

In one embodiment, the laser scanning adopts strip scanning, and the scanning path of each layer is rotated by 67 degrees to carry out staggered scanning and stacking forming.

In one embodiment, the calculation formula of the laser energy density is as follows:

wherein E is laser energy density with the unit of J/mm³(ii) a P is laser power and the unit is W; v is the laser scanning rate in mm/s); h is a laser scanning interval, and the unit is mm; and t is the thickness of the powder layer, and the unit is mm.

Embodiments of the present invention will be described in detail below with reference to specific examples.

The method for producing tantalum articles of examples 1-3 is as follows, and the process parameters and densification results for tantalum articles produced in examples 1-3 are shown in table 1.

A method for preparing a tantalum piece based on a selective laser melting technology comprises the following steps:

placing tantalum metal powder in a powder feeding cylinder of SLM equipment;

argon is input into a forming cavity of the SLM equipment through a gas supply device, so that the oxygen content in the forming cavity is less than 100 ppm;

constructing a model of a target printing sample by using three-dimensional design software, storing the model in an STL format, then guiding the model into slicing software for two-dimensional slicing processing, setting printing process parameters in the slicing processing process, guiding a file into SLM equipment, scanning in a strip shape, rotating the scanning path of each layer by 67 degrees, performing staggered scanning, stacking and forming, and printing to obtain a sample;

the tantalum metal powder of the embodiments 1 to 3 comprises the following components by mass percent: 0.0003% of C, 0.004% of N, 0.0015% of H, 0.0027% of Nb, 0.0049% of Fe, 0.0001% of Ti0.0001% of W, 0.0054% of Mo, 0.0004% of Si, 0.001% of Ni and the balance of Ta.

Table 1:

as can be seen from the data analysis in Table 1, the tantalum pieces obtained in examples 1 to 3 of the present invention had a substrate preheating temperature of 200 ℃, a laser power of 300W, a powder spreading thickness of 30 μm, and a laser energy density of 100J/mm³On the premise that the laser scanning interval is 0.07mm-0.09mm, the laser scanning speed is 1110mm/s-1250mm/s, and the compactness of 99.7543% -99.8853% is achieved, which shows that the printing process parameters set by the invention can prepare the tantalum piece with high compactness.

The method for producing tantalum articles of examples 4-8 is as follows, and the process parameters and densification results for tantalum articles produced in examples 4-8 are shown in table 2.

A method for preparing a tantalum piece based on a selective laser melting technology comprises the following steps:

placing tantalum metal powder in a powder feeding cylinder of SLM equipment;

argon is input into a forming cavity of the SLM equipment through a gas supply device, so that the oxygen content in the forming cavity is less than 100 ppm;

constructing a model of a target printing sample by using three-dimensional design software, storing the model in an STL format, then guiding the model into slicing software for two-dimensional slicing processing, setting printing process parameters in the slicing processing process, guiding a file into SLM equipment, scanning in a strip shape, rotating the scanning path of each layer by 67 degrees, performing staggered scanning, stacking and forming, and printing to obtain a sample;

the tantalum metal powder of examples 4 to 8 comprises the following components in percentage by mass: 0.0005% of C, 0.006% of N, 0.0012% of H, 0.0025% of Nb, 0.0015% of Fe, 0.0006% of Ti, 0.0045% of W, 0.005% of Mo, 0.0002% of Si, 0.001% of Ni and the balance of Ta.

Table 2:

the data analysis in table 1 and table 2 shows that the tantalum piece shown in fig. 6 can be obtained by optimizing the melting process parameters in the laser selective area, and the tantalum piece with the accuracy of +/-0.05 mm, the surface roughness Ra of less than 10 μm and the compactness of 98.7523-99.8853% can be obtained, as shown in fig. 3 and fig. 4, the microstructure analysis of the tantalum piece prepared by the method shows that the tantalum piece prepared by the method has no obvious cracks, and the size of the pore defect is less than 2 μm.

In addition, the following comparative examples 1-5 are also provided, the tantalum members of the comparative examples 1-5 are prepared as follows, and the preparation process parameters of the tantalum members of the comparative examples 1-5 and the compactness results of the obtained tantalum members are shown in the following table 3.

A method for preparing a tantalum piece based on a selective laser melting technology comprises the following steps: placing tantalum metal powder in a powder feeding cylinder of SLM equipment;

argon is input into a forming cavity of the SLM equipment through a gas supply device, so that the oxygen content in the forming cavity is less than 100 ppm;

constructing a model of a target printing sample by using three-dimensional design software, storing the model in an STL format, then guiding the model into slicing software for two-dimensional slicing processing, setting printing process parameters in the slicing processing process, guiding a file into SLM equipment, scanning in a strip shape, rotating the scanning path of each layer by 67 degrees, performing staggered scanning, stacking and forming, and printing to obtain a sample;

wherein, the tantalum metal powder of comparative examples 1-5 comprises the following components by mass percent: 0.0005% of C, 0.006% of N, 0.0012% of H, 0.0025% of Nb, 0.0015% of Fe, 0.0006% of Ti, 0.0045% of W, 0.005% of Mo, 0.0002% of Si, 0.001% of Ni and the balance of Ta.

Table 3:

from the comparative analysis of the data in table 2 and table 3, it can be seen that: according to the preparation method of the tantalum piece, the process parameters of the prepared tantalum piece have obvious influence on the compactness of the obtained tantalum piece, and the high-compactness tantalum piece can be obtained under the combined action of the preparation method and the preparation process parameters, so that the tantalum piece has excellent tensile strength, yield strength and elongation percentage.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.