Electric arc fuse wire additive manufacturing system based on dry ice particles

Abstract

The utility model relates to the technical field of additive manufacturing, in particular to an arc fuse additive manufacturing system based on dry ice particles. The system includes: a substrate; a welding gun and a nozzle are arranged at the tail end of the mechanical arm, the mechanical arm is movably arranged above the base material, the welding gun is used for generating an electric arc to melt a metal wire, the melted metal is deposited on the base material layer by layer, and the nozzle is used for spraying gas carrying dry ice particles outwards. The gas is used for conveying the dry ice particles, the dry ice particles are used for impacting, cooling and cleaning deposited metal, the nozzle is located behind the electric arc in the moving direction of the electric arc, and an obtuse angle is formed between the spraying direction of the dry ice particles and the moving direction of the electric arc. According to the technical scheme, the mechanical property of a component formed by electric arc fuse additive manufacturing can be effectively improved.

Description

Technical Field

[0001] This utility model relates to the field of additive manufacturing technology, and in particular to an electric arc wire additive manufacturing system based on dry ice particles. Background Technology

[0002] Additive manufacturing is an advanced technology based on the discrete-deposition principle, driven by the three-dimensional data of a part to directly manufacture it. It achieves rapid and customized manufacturing of components through a layer-by-layer accumulation method. Arc-wire additive manufacturing technology uses an electric arc as a heat source to melt a metal wire, depositing the molten metal layer by layer according to a pre-set forming path, thus achieving rapid component manufacturing. Because the energy density of an electric arc is much lower than that of lasers and electron beams, the heat input in arc-wire additive manufacturing is large, and the molten pool morphology is difficult to control, resulting in poor component forming accuracy. Simultaneously, due to the severe heat accumulation effect, as the forming height increases, the component temperature continuously rises, the metal solidification rate slows down, the molten pool size increases, forming accuracy further deteriorates, grain growth is severe, and compositional segregation is easily caused, affecting the mechanical properties of the component.

[0003] In related technologies, to reduce heat accumulation in the formed components during arc-wire additive manufacturing, methods such as natural heat dissipation, water immersion, and gas cooling are commonly used to control the temperature of the deposited metal. However, these cooling technologies cannot effectively improve the mechanical properties of components formed by arc-wire additive manufacturing.

[0004] Therefore, there is an urgent need for an arc-fused-wire additive manufacturing system based on dry ice particles to solve the above-mentioned technical problems. Utility Model Content

[0005] This invention provides an arc-fuse additive manufacturing system based on dry ice particles, which can effectively improve the mechanical properties of components formed by arc-fuse additive manufacturing.

[0006] This utility model embodiment provides an arc-fused additive manufacturing system based on dry ice particles, comprising:

[0007] Substrate;

[0008] A robotic arm, with a welding torch and a nozzle at its end, is movably positioned above the substrate. The welding torch generates an electric arc to melt a metal wire, which is then deposited layer by layer onto the substrate. The nozzle ejects gas carrying dry ice particles, which are used to transport the dry ice particles and impact, cool, and clean the deposited metal. The nozzle is located behind the electric arc, and the direction of the dry ice particles ejection is at an obtuse angle to the direction of the electric arc.

[0009] As can be seen from the above scheme, the arc filament additive manufacturing system based on dry ice particles provided by this utility model, by setting a nozzle on the robotic arm, sprays outward gas carrying dry ice particles. The gas is used to transport the dry ice particles, which are used to impact, cool, and clean the deposited metal. This can refine the grains, ensure the stability of the molten pool morphology, and clean the carbon black on the surface of the deposited metal, thereby improving the mechanical properties of the formed component. In addition, along the direction of arc movement, the nozzle is located behind the arc, and the spray direction of the dry ice particles is at an obtuse angle to the direction of arc movement, which can ensure that the carbon dioxide gas generated after the dry ice particles sublimate will not affect the arc initiation. Attached Figure Description

[0010] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0011] Figure 1 A schematic diagram of the structure of the arc-fuse additive manufacturing system based on dry ice particles provided in this embodiment of the present invention;

[0012] Figure 2 This is a schematic diagram showing the positions of the nozzle and the electric arc in an embodiment of the present invention.

[0013] Figure 3 This is a schematic diagram of a first structure of a nozzle provided in an embodiment of the present utility model;

[0014] Figure 4 This is a schematic diagram of a second structure of the nozzle provided in an embodiment of the present utility model;

[0015] Figure 5 This is a schematic diagram of a third structure of the nozzle provided in an embodiment of the present invention.

[0016] Figure label:

[0017] 1-Substrate;

[0018] 2-Robotic arm;

[0019] 21-Welding torch;

[0020] 22-Nozzle;

[0021] 23-Bamboo joint tube. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0023] As mentioned earlier, additive manufacturing technology using lasers and electron beams as heat sources for metal wires has a faster cooling rate (i.e., faster solidification rate) compared to additive manufacturing technology using electric arcs as heat sources. In other words, additive manufacturing using lasers and electron beams as heat sources for metal wires requires less heat input, the molten pool morphology is easier to control, and the formed components have excellent forming accuracy.

[0024] Some related technologies include active cooling and natural cooling. Active cooling involves spraying a gaseous cooling medium onto the surface of the deposited metal, while natural cooling involves extending the interlayer residence time, allowing the component temperature to drop below a preset temperature before starting the next layer of additive manufacturing. One example of active cooling is patent CN116752131A, which discloses a cold spray additive manufacturing method and its application. Specifically, it discloses that the inventor believes that interlayer oxidation occurs in cold spray powder particles during laser heating. The solution is to spray a gaseous cooling medium (i.e., dry ice) downwards directly above the deposition area. The corresponding technical principle and effect is that the gaseous cooling medium forms cooling spots on the deposited area, lowering the temperature within the coverage area and thus preventing interlayer oxidation. In other words, this patent's active cooling method for the deposited metal during the deposition process only cools the deposited metal and does not effectively improve the mechanical properties of components formed by arc-wire additive manufacturing.

[0025] However, in the arc wire additive manufacturing scenario, the following aspects need to be noted: 1) Grain growth needs to be avoided; 2) The temperature of the deposited metal needs to be reduced during the arc wire process to prevent the molten pool morphology from being difficult to control; 3) In order to facilitate arc ignition of the welding torch, wire drawing lubricant is inevitably used during the wire manufacturing process. The wire drawing lubricant will remain on the metal wire, and its main components include elements such as C, H, O, Na, Mg, and Ca. During the welding process, these elements will react with other elements to form dust, which falls on the surface of the deposited metal to form carbon black. Carbon black affects the mechanical properties of the component and the arc ignition of the welding torch, so it is necessary to remove the carbon black.

[0026] Faced with the aforementioned technical problems, the inventors creatively conceived of using dry ice particles, a solid-phase material, to impact the deposited metal. Since the deposited metal has low strength, the high-speed moving dry ice particles can induce plastic deformation, thus refining the grains. Utilizing the physical properties of dry ice (i.e., the endothermic nature of solid-to-gas sublimation), the impact of dry ice particles on the deposited metal can rapidly cool it, ensuring a stable molten pool. Furthermore, the cleaning principle of dry ice particles (i.e., when dry ice particles sublimate upon heating, changing from a solid to a gaseous phase, the sudden increase in pressure on the deposited metal surface causes the carbon black on the surface to break up and be swept away by the gas generated during sublimation, thus cleaning the carbon black) effectively removes the carbon black from the deposited metal surface, creating better conditions for the deposition of the next metal layer, reducing the chance of defects, and thereby improving the mechanical properties of the component.

[0027] like Figure 1 As shown, one embodiment of this utility model provides an arc-fused wire additive manufacturing system based on dry ice particles. The system includes a substrate 1 and a robotic arm 2. The end of the robotic arm 2 is provided with a welding torch 21 and a nozzle 22. The robotic arm 2 is movably positioned above the substrate 1. The welding torch 21 is used to generate an electric arc to melt the metal wire. The molten metal is deposited layer by layer on the substrate 1. The nozzle 22 is used to spray gas carrying dry ice particles outward. The gas is used to transport the dry ice particles. The dry ice particles are used to impact, cool, and clean the deposited metal. Along the direction of arc movement, the nozzle 22 is located behind the arc, and the spraying direction of the dry ice particles is at an obtuse angle to the direction of arc movement.

[0028] In this embodiment, a nozzle 22 is installed on the robotic arm 2. The nozzle 22 sprays gas carrying dry ice particles outward. The gas is used to transport the dry ice particles, which are used to impact, cool, and clean the deposited metal. This refines the grains, ensures the stability of the molten pool morphology, and cleans the carbon black from the surface of the deposited metal, thereby improving the mechanical properties of the formed component. Furthermore, along the direction of arc movement, the nozzle 22 is located behind the arc, and the spray direction of the dry ice particles forms an obtuse angle with the direction of arc movement (i.e., ...). Figure 2 Angle a) in the equation ensures that the carbon dioxide gas produced after the dry ice particles sublimate will not affect the arc initiation.

[0029] In one embodiment of this utility model, the obtuse angle is between 120° and 150°. For example, it can be 120°, 130°, 140°, 150°, etc., and is not specifically limited here.

[0030] Understandably, if the obtuse angle range is too small, for example, greater than 90° and less than 120°, the carbon dioxide gas generated by sublimation may be blown to the molten pool, which may affect the arc ignition of the welding torch. If the obtuse angle range is too large, for example, greater than 150° and less than 180°, the contact time between the dry ice particles and the deposited metal may not be long enough, resulting in incomplete impact, cooling and cleaning of the deposited metal, thus failing to effectively improve the mechanical properties of the component.

[0031] In one embodiment of this invention, the gas is an inert gas or nitrogen. This configuration further prevents the formation of an oxide film on the deposited metal, thereby further improving the mechanical properties of the component.

[0032] Of course, the gas can also be air (such as compressed air), and the type of gas is not specifically limited here.

[0033] In one embodiment of this invention, the gas flow rate is 50–400 m / s. For example, it can be 50 m / s, 100 m / s, 200 m / s, 300 m / s, 400 m / s, etc., and is not specifically limited here.

[0034] In one embodiment of this invention, the flow rate of dry ice particles is 0.01 to 1 L / min. For example, it can be 0.01 L / min, 0.05 L / min, 0.1 L / min, 0.5 L / min, 1 L / min, etc., and is not specifically limited here.

[0035] In one embodiment of this invention, the particle size of the dry ice particles is 0.1–5 mm. For example, it can be 0.1 mm, 1 mm, 2 mm, 3 mm, 5 mm, etc., and is not specifically limited here.

[0036] In one embodiment of this utility model, the distance from the center of the nozzle 22 to the metal wire (i.e. Figure 2 The distance b) is 10-50mm. For example, it can be 10mm, 20mm, 30mm, 40mm, 50mm, etc., without specific limitation.

[0037] like Figures 3 to 5 As shown, in one embodiment of this utility model, the opening of the nozzle 22 is square, circular, or elliptical, and no specific limitation is made here. Preferably, the opening of the nozzle 22 is elliptical.

[0038] Please continue reading Figure 1 In one embodiment of the present invention, a bamboo tube 23 for adjusting the position of the nozzle 22 is connected above the nozzle 22.

[0039] In this embodiment, by setting the bamboo tube 23, the orientation (i.e., direction and position) of the nozzle 22 can be adjusted to better adjust the relevant process parameters of the dry ice particles according to the actual situation, thereby improving the mechanical properties of the component.

[0040] Furthermore, this utility model embodiment also provides a method for additive manufacturing of arc-fused wires based on dry ice particles. Based on the system mentioned in any of the above embodiments, the method includes:

[0041] The robotic arm 2 drives the welding torch 21 and nozzle 22 to move above the substrate 1 along a preset path;

[0042] The welding torch 21 generates an electric arc to melt the metal wire, and the molten metal is deposited layer by layer on the substrate 1.

[0043] Gas carrying dry ice particles is ejected outward using nozzle 22;

[0044] Dry ice particles are used to impact, cool, and clean deposited metal.

[0045] It should be noted that this method and the dry ice particle-based arc filament additive manufacturing system in the above embodiments are based on the same inventive concept, and therefore have the same beneficial effects. The beneficial effects of the method will not be elaborated here.

[0046] It should be noted that in this invention, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus.

[0047] Finally, it should be noted that the above description is only a preferred embodiment of this utility model and is used only to illustrate the technical solution of this utility model, and is not intended to limit the protection scope of this utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model are included within the protection scope of this utility model.

Claims

1. An electric arc fuse additive manufacturing system based on dry ice particles, characterized in that, Comprise: a base material (1); a mechanical arm (2) provided with a welding gun (21) and a nozzle (22) at the end, the mechanical arm (2) is movably arranged above the base material (1), the welding gun (21) is used to generate an electric arc to melt a metal wire, the melted metal is deposited on the base material (1) layer by layer, the nozzle (22) is used to spray gas carrying dry ice particles outward, the gas is used to transport the dry ice particles, the dry ice particles are used to impact, cool and clean the deposited metal, along the direction of the arc movement, the nozzle (22) is located behind the electric arc, the spray direction of the dry ice particles is obtuse with the direction of the arc movement, so that the carbon dioxide gas generated after the sublimation of the dry ice particles will not affect the arc starting.

2. The system of claim 1, wherein, The obtuse angle is in the range of 120-150°.

3. The system of claim 1, wherein, The flow rate of the gas is 50-400 m / s.

4. The system of claim 1, wherein, The flow rate of the dry ice particles is 0.01-1 L / min.

5. The system of claim 1, wherein, The particle size of the dry ice particles is 0.1-5 mm.

6. The system of claim 1, wherein, The distance from the center of the nozzle (22) to the metal wire is 10-50 mm.

7. The system of claim 1, wherein, The gas is inert gas or nitrogen.

8. The system of claim 1, wherein, The opening of the nozzle (22) is square, circular or oval.

9. The system of claim 1, wherein, A bamboo joint pipe (23) for adjusting the orientation of the nozzle (22) is connected above the nozzle (22).

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