High-flux gradient deposition method based on additive manufacturing

Abstract

The invention discloses a high-flux gradient deposition method based on additive manufacturing, and belongs to the technical field of additive manufacturing. The invention aims to solve the problems that the existing additive high-flux preparation efficiency is low, and microelement regulation and control are difficult to realize by an electron beam fuse technology. The method comprises the following steps: 1, establishing a three-dimensional model by using three-dimensional modeling software; designing alloy components of the three-dimensional model, wherein the alloy components comprise a printed component interval and a deposition layer number; 2, calculating and setting the relative feeding rate of the inner wire and the outer wire in each component interval in the printing process; 3, printing; and 4, adjusting the relative feeding rate of the inner wire and the outer wire in the printing process to realize component change between different layers. According to the method, through the mode that inner wire feeding and outer wire feeding of the electron beam fuse deposition technology are combined, microelements of the electron beam fuse additive can be regulated and controlled, the flexibility of electron beam fuse additive manufacturing is improved, and the application range of the electron beam fuse additive manufacturing is widened; the problems that an existing additive high-flux preparation efficiency is low, and microelement regulation and control are difficult to achieve through an electron beam fuse technology are solved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of additive manufacturing technology. BACKGROUND

[0002] High-throughput screening is a large-scale, automatic design, production and accelerated new formula discovery technology, which uses high-throughput technology to develop new materials and provides a broad prospect for exploring new multi-component alloy formula and expanding the material database. High-throughput gradient deposition can prepare alloy samples of multiple components in one printing process, realize the deposition of different components in different layers of the same sample, and greatly accelerate the innovation and development speed of alloy and process matching.

[0003] Additive manufacturing technology is a technology that realizes the rapid preparation of parts through layer-by-layer stacking of materials. Compared with traditional processing methods, it has the advantages of high program efficiency and no mold limitation. Additive manufacturing technology combined with high-throughput screening can realize the rapid preparation of gradient materials. The existing additive manufacturing technology combined with high-throughput screening is mainly powder additive. According to the content change, different content powder is mixed and then melted and solidified by high-energy beam to realize high-throughput preparation. However, the powder mixing process increases the process flow and easily causes defects such as oxidation inclusion and porosity, reducing the efficiency of high-throughput screening and the quality of gradient forming. Electron beam wire deposition technology uses electron beam as heat source and wire as material to melt the metal wire and accumulate layer by layer to realize the preparation of metal parts. In the absence of molds, high-density parts with excellent mechanical properties are prepared. Compared with arc wire additive in atmospheric environment, the vacuum condition effectively avoids the generation of oxidation inclusions; compared with laser wire additive with small molten pool, the high power of electron beam with large molten pool has higher melting efficiency; compared with powder additive, wire additive has higher forming efficiency and density.

[0004] The existing electron beam wire deposition realizes the continuous transportation of metal materials into the molten pool in the form of internal or external wire feeding. The external wire feeding system of electron beam wire deposition can replace the wire under the condition of maintaining vacuum without opening the cabin door, realizing the continuous printing of large-size parts, but it is difficult to stably transport small-diameter thin metal wires that cannot pass through the vacuum sealing pad and soft metal wires that are easy to bend and deform, and it cannot add and control trace elements. The internal wire feeding mechanism can effectively avoid such problems, but the single internal wire feeding mechanism is limited by the storage of wire in the vacuum chamber, and it is difficult to continuously print large-size parts and a large number of samples. Based on the above problems, the present application proposes an internal and external wire feeding cooperation mode. The internal and external wire feeding cooperation mode can realize the addition of trace amounts of different components and continuous printing, and is not limited by the ratio of wire diameter. Compared with metal powder additive, the internal and external wire feeding cooperation mode reduces the powder mixing process and realizes high-throughput preparation of materials through internal and external wire feeding cooperation and interlayer gradient deposition. SUMMARY

[0005] The application aims to solve the problems of low efficiency of existing additive high-throughput preparation and difficulty in realizing trace element regulation by electron beam melting wire technology, and provides a high-throughput gradient deposition method based on additive manufacturing.

[0006] The application provides a high-throughput gradient deposition method based on additive manufacturing, so as to realize high-throughput preparation of wire additive manufacturing, prepare a uniform multi-component sample in one printing process, realize changes of components, electron beam power and platform moving rate between layers, has great significance for material selection, process development and optimization of wire additive manufacturing high-throughput preparation alloy materials, quickly screens the combination of material components and its preparation process, greatly shortens the process from component design, raw material ratio to process development, and accelerates the material research and development process.

[0007] A high-throughput gradient deposition method based on additive manufacturing is completed according to the following steps:

[0008] I. A three-dimensional model is established by using a three-dimensional modeling software; the alloy components of the three-dimensional model are designed, including the printed component interval and the deposition layer number;

[0009] II. According to the components, radii, densities and mass fractions in the alloy of the inner wire and the outer wire, the relative feeding rates of the inner wire and the outer wire in each component interval in the printing process are calculated and the wire feeding speed is set;

[0010] III. The inner wire feeding and the outer wire feeding of the electron beam wire deposition device are cooperated to print on the substrate of the working platform in a set path;

[0011] IV. After printing a component interval, the relative feeding rates of the inner wire and the outer wire in the printing process are adjusted,

[0012] V. The component change between different layers is realized, and a high-throughput gradient alloy is obtained.

[0013] Compared with the prior art, the application has the following advantages and beneficial effects:

[0014] I. The high-throughput gradient deposition method based on additive manufacturing has the advantages of fast deposition speed, large controllable range of elements, realization of high-throughput preparation of different component metal materials, short process flow, and realization of preparation of large-size gradient materials; provides design guidance for new material and additive process research and development process, realizes rapid research and development and optimization screening of new materials and matching processes;

[0015] Secondly, the electron beam fuse deposition technology is combined with the high-throughput preparation technology, element change is completed synchronously in a deposition process, the high-throughput preparation and the design and development of new materials can be realized, and the sample prepared by the method can be directly used for subsequent material characterization and performance test experiment, so that the composition and preparation process of the material are efficiently screened, and the research and development cycle of new materials and forming processes is greatly shortened.

[0016] Thirdly, the electron beam fuse deposition technology is combined with the high-throughput preparation technology, element change is completed synchronously in a deposition process, the high-throughput preparation and the design and development of new materials can be realized, and the sample prepared by the method can be directly used for subsequent material characterization and performance test experiment, so that the composition and preparation process of the material are efficiently screened, and the research and development cycle of new materials and forming processes is greatly shortened. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 FIG. 1 is a structural schematic diagram of the electron beam fuse deposition device;

[0018] Figure 2 FIG. 2 is a structural schematic diagram of the inner wire feeding device; Figure 1

[0019] Figure 3 FIG. 5 is a metallographic microstructure of the high-throughput gradient alloy formed in Example 1 along the forming direction;

[0020] Figure 4 FIG. 6 is a composition comparison diagram of Ti content in different composition intervals of the high-throughput gradient alloy formed in Example 1. DETAILED DESCRIPTION

[0021] Specific embodiment one: the high-throughput gradient deposition method based on additive manufacturing is completed according to the following steps:

[0022] I. A three-dimensional model is established by using a three-dimensional modeling software; the alloy composition of the three-dimensional model is designed, including the composition interval and the number of deposition layers;

[0023] II. According to the composition, radius, density and mass fraction in the alloy of the inner wire and the outer wire, the relative feeding rate of the inner wire and the outer wire in each composition interval in the printing process is calculated, and the wire feeding speed is set;

[0024] III. The inner wire feeding and the outer wire feeding of the electron beam fuse deposition device are cooperated to print on the substrate of the working platform in a set path;

[0025] IV. After printing one composition interval, the relative feeding rate of the inner wire and the outer wire in the printing process is adjusted,

[0026] V. The composition change between different layers is realized, and the high-throughput gradient alloy is obtained. ​

[0027] Specific implementation two: the difference between this embodiment and the first embodiment is that the alloy composition in step one is Cu-15Ni-8Sn-xTi, x is in the range of 0.1-0.5wt.%, and is divided into multiple component gradients according to the content of Ti. The other steps are the same as the first embodiment.

[0028] Specific implementation three: the difference between this embodiment and one of the first or second embodiments is that the alloy composition in step one is Cu-15Ni-8Sn-xTi, which is divided into five component gradients according to the content of Ti, and the content of Ti along the deposition direction is 0.1wt%, 0.2wt%, 0.3wt%, 0.4wt%, and 0.5wt% respectively. The other steps are the same as the first or second embodiment.

[0029] Specific implementation four: the difference between this embodiment and one of the first to third embodiments is that the composition of the outer wire in step two is Cu-15Ni-8Sn alloy. The other steps are the same as the first to third embodiments.

[0030] Specific implementation five: the difference between this embodiment and one of the first to fourth embodiments is that the composition of the inner wire in step two is Ti wire. The other steps are the same as the first to fourth embodiments.

[0031] Specific implementation six: the difference between this embodiment and one of the first to fifth embodiments is that the diameter of the inner wire in step two is 0.2mm-2mm; the diameter of the outer wire is 1.6mm-4mm. The other steps are the same as the first to fifth embodiments.

[0032] Specific implementation seven: the difference between this embodiment and one of the first to sixth embodiments is that the calculation formula of the relative feed rate of the inner wire and the outer wire in step two is:

[0033] ;

[0034] In the formula, is the wire feed rate of the inner wire, unit: m / s; is the wire feed rate of the outer wire, unit: m / s;

[0035] is the radius of the inner wire, unit: mm; is the radius of the outer wire, unit: mm;

[0036] is the density of the inner wire, unit: g / cm 3 ; is the density of the outer wire, unit: g / cm 3 ;

[0037] is the mass fraction of the inner wire in the alloy, in wt.%; is the mass fraction of the outer wire in the alloy, in wt.%. Other steps are the same as those in Embodiments 1-6.

[0038] Embodiment 8: The difference between this embodiment and any one of Embodiments 1-7 is that the inner wire and the outer wire need to be cleaned before printing; the cleaning method is as follows: first, clean the inner wire and the outer wire with anhydrous ethanol, then dry at 60°C for 5-6 hours, polish the surface of the cleaned inner wire and outer wire to be smooth and clean, clean again with anhydrous ethanol and then dry at 60°C for 5-6 hours. Other steps are the same as those in Embodiments 1-7.

[0039] Embodiment 9: The difference between this embodiment and any one of Embodiments 1-8 is that the electron beam wire deposition device in step three includes an electron gun 1, a vacuum chamber 2, a lower beam hole 3, an outer wire feeding reel 4, a substrate 5, an inner wire feeding device 6, a motion platform 7, an inner wire feeding support 8, a wire outlet fixing rod 9, a wire guide tube 10, a wire outlet 11 and a wire feeding wheel 12; the electron gun 1 is fixed at the top of the vacuum chamber 2, the lower beam hole 3 is below the electron gun 1, and the inner wire feeding device 6 is arranged inside the vacuum chamber 2 through the fixing rod 8; the outer wire feeding reel 4 and the wire feeding wheel 12 are arranged at the top of the vacuum chamber 2, the wire guide tube 10 is fixed inside the vacuum chamber 2 through the wire outlet fixing rod 9, and the wire guide tube 10 feeds the outer wire to the wire outlet 11; the motion platform 7 is arranged inside the vacuum chamber 2, and the substrate 5 is fixed on the motion platform 7; the motion platform 7 has six degrees of freedom; and the material of the motion platform 7 is steel. Other steps are the same as those in Embodiments 1-8.

[0040] Embodiment 10: The difference between this embodiment and any one of Embodiments 1-9 is that the inner wire feeding device 6 includes an inner wire feeding wheel 601, an inner wire guide tube 602, a wire reel 603, a fixed plate 604, an inner wire outlet fixing rod 605, a wire outlet 606 and an inner wire 607; the inner wire guide tube 602 is connected with the wire outlet 606, the inner wire 607 is wound on the wire reel 603, and the inner wire guide tube 602 feeds the inner wire 607 to the wire outlet 606; the inner wire feeding wheel 601 and the wire reel 603 are arranged on the fixed plate 604, the fixed plate 604 is connected with the inner wire feeding support 8 and is installed on the inner wall of the vacuum chamber 2. Other steps are the same as those in Embodiments 1-9.

[0041] The beneficial effects of the present application are verified by the following examples:

[0042] Example 1: A high-throughput gradient deposition method based on additive manufacturing, which is completed according to the following steps:

[0043] I. Clean the inner wire and the outer wire:

[0044] Firstly, the inner wire and the outer wire are cleaned with anhydrous ethanol, then dried at 60℃ for 5h, and then the surface of the cleaned inner wire and outer wire is polished to be smooth and clean, and then cleaned with anhydrous ethanol again and dried at 60℃ for 5h;

[0045] II. Establishing a three-dimensional model using three-dimensional modeling software; designing the alloy composition of the three-dimensional model, including the printed composition interval and the deposited layer number;

[0046] The alloy composition in step two is Cu-15Ni-8Sn-xTi, which is divided into five composition gradients according to the content of Ti, and the content of Ti along the deposition direction is 0.1wt%, 0.2wt%, 0.3wt%, 0.4wt%, and 0.5wt% respectively;

[0047] III. Using a pure Ti wire with a diameter of 0.2mm as the inner wire and a Cu-15Ni-8Sn alloy with a diameter of 1.6mm as the outer wire, the pure Ti wire and the Cu-15Ni-8Sn alloy are respectively installed on the inner wire feeding device 6 and the outer wire feeding device 4, and the relative position of the inner wire feeding device 6 and the wire outlet 11 is adjusted to be located directly below the lower beam hole 3; the dried substrate 5 is fixed on the moving platform 7;

[0048] IV. Calculating the relative feeding rate of the pure Ti wire and the Cu-15Ni-8Sn alloy wire with Ti content of 0.1wt%, 0.2wt%, 0.3wt%, 0.4wt%, and 0.5wt% respectively, and setting the wire feeding speed;

[0049] The calculation formula of the relative feeding rate of the inner wire and the outer wire in step four is:

[0050] ;

[0051] In the formula, is the wire feeding rate of the inner wire, unit: m / s; is the wire feeding rate of the outer wire, unit: m / s;

[0052] is the radius of the inner wire, unit: mm; is the radius of the outer wire, unit: mm;

[0053] is the density of the inner wire, unit: g / cm 3 ; is the density of the outer wire, unit: g / cm 3 ;

[0054] is the mass fraction of the inner wire in the alloy, unit: wt.%; wt. % for the outer wire in the alloy;

[0055] V. Vacuum the vacuum chamber 2, and after reaching the beam vacuum level under the electron beam, preheat the substrate 5 using the electron beam;

[0056] VI. The electron gun 1 excites the electron beam to pass through the beam hole 3 to the substrate 5 to form a molten pool, the inner wire feeding wheel 601 and the wire feeding wheel 12 rotate to feed the inner wire and the outer wire into the molten pool, and the moving platform 7 moves according to the predetermined trajectory until a layer of printing is completed;

[0057] VII. The electron gun 1 stops the beam, and the moving platform 7 is lowered by one layer thickness;

[0058] VIII. Repeat steps VI to VII to print layer by layer, and after printing a component interval, adjust the relative feeding rate of the inner wire and the outer wire during printing, and continue to repeat steps VI to VII to print layer by layer,

[0059] to realize the composition change between different layers and obtain the formed high-flux gradient alloy.

[0060] Figure 3 The metallograph of the formed high-flux gradient alloy in Example 1 along the forming direction;

[0061] From Figure 3 It can be seen that the bottom is the substrate and the upper part is the printed sample, and numbers 1-5 are the positions of the first to fifth layers printed;

[0062] Figure 4 The composition comparison chart of Ti content in different component intervals of the formed high-flux gradient alloy in Example 1:

[0063] From Figure 4 1-5 in the figure, the Ti content of the first to fifth layers printed is 0.12wt.%, 0.2wt.%, 0.32wt.%, 0.43wt.%, and 0.51wt.% respectively, which is equivalent to the designed composition; Figure 4 6 in the figure is the change of Ti content with the printing process, and from the figure it can be seen that the Ti content gradually increases from 0.12wt.% to 0.51wt.% with the gradual accumulation of the printed layers.

Claims

1. A high-throughput gradient deposition method based on additive manufacturing, characterized in that The method is specifically completed according to the following steps:

1. Use 3D modeling software to create a 3D model; design the alloy composition of the 3D model, including the printing composition range and the number of deposition layers; 2. Calculate the relative feed rate of the inner and outer wires in each composition range during printing and set the wire feeding speed based on their composition, radius, density, and mass fraction in the alloy.

3. Printing is performed on a substrate on a work platform along a set path by coordinating the internal and external wire feeding of the electron beam fuse deposition device; 4. After printing a composition interval, adjust the relative feed rate of the inner and outer wires during the printing process to achieve composition changes between different layers and obtain a high-throughput gradient alloy.

2. A high-throughput gradient deposition method based on additive manufacturing according to claim 1, characterized in that The alloy composition described in step 1 is Cu-15Ni-8Sn-xTi, where x ranges from 0.1 to 0.5 wt.%, and is divided into multiple composition gradients according to the Ti content.

3. A high-throughput gradient deposition method based on additive manufacturing according to claim 2, characterized in that The alloy composition described in step 1 is Cu-15Ni-8Sn-xTi, which is divided into 5 composition gradients according to the Ti content. The Ti content along the deposition direction is 0.1wt%, 0.2wt%, 0.3wt%, 0.4wt%, and 0.5wt%, respectively.

4. A high-throughput gradient deposition method based on additive manufacturing according to claim 1, characterized in that The composition of the outer wire described in step 2 is Cu-15Ni-8Sn alloy.

5. A high-throughput gradient deposition method based on additive manufacturing according to claim 1, characterized in that The component of the inner wire described in step 2 is Ti wire.

6. A high-throughput gradient deposition method based on additive manufacturing according to claim 1, characterized in that The diameter of the inner wire described in step 2 is 0.2mm~2mm; the diameter of the outer wire is 1.6mm~4mm.

7. A high-throughput gradient deposition method based on additive manufacturing according to claim 1, characterized in that The calculation formula for the relative feed rate of the inner and outer wires described in step 2 is: ； In the formula is the wire feeding rate of the inner wire, in m / s; The wire feeding rate of the outer wire is m / s; is the radius of the inner thread, in mm; is the radius of the outer wire, in mm; The density of the inner wire, in g / cm 3 ; The radius of the outer wire, in g / cm 3 ; is the mass fraction of the inner wire in the alloy, in wt.%; is the mass fraction of the external wire in the alloy, in wt.%.

8. A high-throughput gradient deposition method based on additive manufacturing according to claim 1, characterized in that The inner and outer wires need to be cleaned before printing; the cleaning method is: first, use anhydrous ethanol to clean the inner and outer wires, then dry them at 60°C for 5h~6h, then polish the surfaces of the cleaned inner and outer wires until they are smooth and clean, clean them again with anhydrous ethanol, and then dry them at 60°C for 5h~6h.

9. A high-throughput gradient deposition method based on additive manufacturing according to claim 1, characterized in that The electron beam fuse deposition device described in step 3 includes an electron gun (1), a vacuum chamber (2), a lower beam hole (3), an external wire feeding reel (4), a base plate (5), an internal wire feeding device (6), a moving platform (7), an internal wire feeding bracket (8), a wire outlet nozzle fixing rod (9), a wire guide tube (10), a wire outlet nozzle (11) and a wire feeding wheel (12); the electron gun (1) is fixed on the top of the vacuum chamber (2), the lower beam hole (3) is below the electron gun (1), and the internal wire feeding device (6) is connected to the wire feeding wheel (12) by the fixing rod. (8) is arranged inside the vacuum chamber (2); the external wire feeding reel (4) and the wire feeding wheel (12) are arranged on the top of the vacuum chamber (2); the wire guide tube (10) is fixed inside the vacuum chamber (2) through the wire outlet nozzle fixing rod (9), and the wire guide tube (10) transports the external wire to the wire outlet nozzle (11); the motion platform (7) is arranged in the vacuum chamber (2), and the base plate (5) is fixed on the motion platform (7); the motion platform (7) has six degrees of freedom; the material of the motion platform (7) is steel.

10. A high-throughput gradient deposition method based on additive manufacturing according to claim 9, characterized in that The inner wire feeding device (6) comprises an inner wire feeding wheel (601), an inner wire feeding guide tube (602), a wire reel (603), a fixed plate (604), an inner wire feeding nozzle fixed rod (605), a wire outlet nozzle (606) and an inner wire (607); the inner wire feeding guide tube (602) is connected to the wire outlet nozzle (606), the inner wire (607) is wound on the wire reel (603), and the inner wire feeding guide tube (602) transports the inner wire (607) to the wire outlet nozzle (606); the inner wire feeding wheel (601) and the wire reel (603) are arranged on the fixed plate (604), and the fixed plate (604) is connected to the inner wire feeding bracket (8) and installed on the inner wall of the vacuum chamber (2).

Images