A plasma arc fuse additive device based on vector air flow driven arc swing

Abstract

The application discloses a kind of plasma arc fuse additive devices based on vector air flow driving arc swing, it is related to electric arc additive manufacturing technical field.The application under the condition of plasma arc additive, using four auxiliary ion gas to the vector control of electric arc, make electric arc directional movement and morphological change, and then adjust auxiliary ion gas flow combination, realize the different regular swing of electric arc, such as sawtooth swing, rectangular swing and spiral swing etc..Swing electric arc in the application has the effect of exerting stirring to molten pool, and prolongs metal solidification time, promotes bubble to escape molten pool, reaches the effect of refining grain and optimizing workpiece surface quality, reduces porosity, improves mechanical strength, to improve the organization performance of additive manufacturing.

Description

Technical Field

[0001] This invention belongs to the field of electric arc additive manufacturing technology, and more specifically, it relates to a plasma arc filament additive manufacturing technology based on vector airflow-driven arc oscillation. Background Technology

[0002] Additive manufacturing technology, also known as 3D printing or rapid prototyping, is a novel manufacturing technology based on the principle of layer-by-layer manufacturing. It uses a method of depositing materials layer by layer to directly manufacture physical parts from digital models. Its forming process is not constrained by traditional design principles, has high material utilization, and can achieve rapid prototyping of complex-shaped parts. Additive manufacturing technology can be categorized according to the heat source, including laser additive manufacturing, electron beam additive manufacturing, and arc additive manufacturing. Among these, arc additive manufacturing has attracted widespread attention due to its advantages such as high deposition rate, simple equipment, and low cost.

[0003] Plasma arc additive manufacturing technology offers significant advantages over electron beam and laser beam technologies due to its lower cost, lack of spatter during the additive process, and higher deposition rate. However, the short gas emission time makes it prone to forming pores in the molten pool, particularly in aluminum alloy additive manufacturing. The presence of micropores can lead to stress concentration, resulting in lower plasticity and tensile strength in the vertical direction compared to the horizontal direction. This also contributes to the anisotropy of tensile properties in aluminum alloys. Therefore, porosity is one of the most significant challenges affecting the application of additive manufacturing in aluminum alloys.

[0004] Patent CN109317793A discloses a plasma arc filament additive manufacturing apparatus and method. This method monitors the process, converting temperature values ​​into electrical signals and feeding them back to the control system in real time. The control system compares the set temperature with the real-time temperature. When the real-time temperature is lower than the target value for workpiece adjustment, the plasma arc moves to a low-temperature region for heating, effectively reducing deformation and cracking of printed parts caused by uneven temperature distribution during the printing of large components. However, this patent does not reduce porosity or minimize stress concentration caused by micropores.

[0005] This invention drives the electric arc to oscillate by controlling the vector airflow. In the plasma arc filament additive manufacturing process, the electric arc is directionally moved and its shape changes. This adjusts the auxiliary ion airflow combination, and the oscillating electric arc stirs the molten pool, prolongs the metal solidification time, and promotes the escape of bubbles from the molten pool. This achieves the effects of refining grains, optimizing workpiece surface quality, reducing porosity, and improving mechanical strength, thereby improving the microstructure and properties of additive manufacturing. Summary of the Invention

[0006] The technical problem this invention aims to solve is to provide a plasma arc filament additive manufacturing technology based on vector airflow-driven arc oscillation. This addresses the issue of excessive porosity affecting the microstructure and properties of the additively manufactured material during plasma arc filament additive manufacturing. This technology utilizes four auxiliary ion gases to vector-control the arc under plasma arc additive manufacturing conditions, enabling directional movement and shape changes in the arc. By adjusting the combination of auxiliary ion gas flows, different oscillation patterns of the arc can be achieved, such as sawtooth oscillation, rectangular oscillation, and spiral oscillation. The oscillating arc stirs the molten pool and prolongs the metal solidification time, promoting the escape of bubbles from the molten pool. This refines the grains, optimizes the surface quality of the workpiece, reduces porosity, and improves mechanical strength, thereby improving the microstructure and properties of the additively manufactured material.

[0007] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0008] A plasma arc welding wire additive manufacturing technology based on vector airflow-driven arc oscillation, employing a side-axis wire feeding method, includes a plasma welding torch, a shielding gas cylinder, an ion gas cylinder, a welding power source, a wire feeding device, a solenoid valve, an auxiliary ion gas cylinder, a computer control terminal, and a substrate.

[0009] The protective gas cylinder, ion gas cylinder, and auxiliary ion gas cylinder are all connected to the plasma welding torch via pipes. The welding power source is electrically connected to the plasma welding torch. The wire feeding device is fixedly connected to the plasma welding torch via a connecting plate. During the arc additive manufacturing process, the heat source required for additive deposition is provided by the welding power source electrically connected to the plasma welding torch. The computer control terminal is electrically connected to the plasma welding torch and controls the movement of the plasma welding torch and the wire feeding device in three dimensions. The solenoid valve is connected to the auxiliary ion gas cylinder. The computer control terminal is electrically connected to the solenoid valve and uses electrical signals to control the opening and closing of the solenoid valve, thereby controlling the on / off state of the auxiliary ion gas. The substrate is located below the plasma welding torch.

[0010] Preferably, the nozzle of the plasma welding torch includes a tungsten electrode, a plasma gas channel, an auxiliary ion gas channel, a protective gas channel, and a welding torch nozzle protective cover. The tungsten electrode, plasma gas channel, auxiliary ion gas channel, and protective gas channel are all located inside the welding torch nozzle protective cover. The tungsten electrode is located at the center of the welding torch nozzle protective cover, and the plasma gas channel, auxiliary ion gas channel, and protective gas channel are located around the tungsten electrode.

[0011] Preferably, the auxiliary ion gas channel has four channels, which are evenly arranged around the tungsten electrode along the circumference.

[0012] Preferably, the diameter of the gas passage of the auxiliary ion gas channel is 1 mm, and the inward reduction of the tungsten electrode is 3 mm.

[0013] Preferably, the four auxiliary ion channels are designated as channel A, channel C, channel B, and channel D in a clockwise direction, with channel A and channel B positioned opposite each other, and channel C and channel D positioned opposite each other. The four auxiliary ion channels form different arc oscillation forms, including but not limited to the following four methods:

[0014] 1. Arc stretching and flattening: In the first half of the cycle, open the opposing airways A and B, and close the airways C and D; in the second half of the cycle, open the opposing airways C and D, and close the airways A and B.

[0015] 2. Arc sawtooth oscillation: In the first half of the cycle, adjacent airways A and C are opened, while airways B and D are closed; in the second half of the cycle, opposing airways B and D are opened, while airways A and C are closed.

[0016] III. Arc Rectangular Oscillation: Divide the rotation period of the arc rectangle into four equal parts, namely time intervals T1, T2, T3, and T4; during time interval T1, open airways A and C, and close airways B and D; during time interval T2, open airways A, C, and D, and close airway B; during time interval T3, open airways B and D, and close airways A and C; during time interval T4, open airways B, C, and D, and close airway A.

[0017] IV. Arc Spiral Oscillation: Divide the period of arc spiral rotation into four equal parts, namely time period T1, time period T2, time period T3, and time period T4; during time period T1, open airway A, airway C, and airway D, and close airway B; during time period T2, open airway A, airway B, and airway C, and close airway D; during time period T3, open airway B, airway C, and airway D, and close airway A; during time period T4, open airway A, airway B, and airway D, and close airway C.

[0018] Preferably, the welding wire used in the wire feeding device is made of aluminum alloy, stainless steel, carbon steel, or titanium alloy.

[0019] Preferably, the gas in the ion gas cylinder and the auxiliary ion gas cylinder is argon or a helium-argon mixture; the gas in the protective gas cylinder is argon, helium, or a helium-argon mixture.

[0020] Preferably, the additive manufacturing process includes the following steps:

[0021] Step 1: Fix the substrate to be deposited on the additive manufacturing stage and set the flow rates of the main ion gas and the protective gas. During the additive manufacturing process, both the main ion gas and the protective gas are in the open state, and the vector arc is controlled by closing the four auxiliary ion gas channels.

[0022] Turn on the welding power supply, set the welding current, and use the computer control terminal to control the three-dimensional motion mechanism to adjust the relative position of the plasma welding gun and the substrate to be deposited, so that it is positioned above the substrate at a certain position.

[0023] Step 2: Start the welding power supply and three-dimensional motion device, and control the plasma welding gun to perform additive deposition according to the predetermined trajectory. During the additive process, the four auxiliary ion gases control the arc to stretch and flatten or oscillate in a sawtooth shape, a rectangular shape, or a spiral shape according to the set time and sequence.

[0024] Step 3: After deposition is complete, control the three-dimensional motion device to return the plasma welding torch to its initial position and raise it to a certain height;

[0025] Step 4: Repeat steps 2 and 3 to perform the additive deposition cycle until the desired structural component is obtained, then end the additive process.

[0026] The beneficial effects of adopting the above technical solution are as follows:

[0027] (1) The present invention utilizes the opening and closing of four auxiliary ion gases to drive the electric arc to oscillate without the need for an external magnetic field and electrodes, resulting in lower cost.

[0028] (2) The present invention can change the shape of the arc oscillation by changing the flow rate of the auxiliary ion gas or the opening and closing of the four auxiliary ion gas channels, and can adjust different arc oscillations according to the needs, thereby improving the adaptability to different arc oscillation requirements.

[0029] (3) The present invention stirs the molten pool by electric arc oscillation and prolongs the metal solidification time, which promotes the escape of bubbles from the molten pool, thereby reducing porosity, refining grains and improving additive manufacturing properties. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the overall structure of a plasma arc fuse additive manufacturing device based on vector airflow-driven arc oscillation;

[0031] Figure 2 A schematic diagram of the cross-sectional structure of the nozzle;

[0032] Figure 3 yes Figure 2 Schematic diagram of the cross-sectional structure of the middle AA section;

[0033] Figure 4 These are schematic diagrams of arc-free oscillation and arc elongation and flattening, sawtooth oscillation, rectangular oscillation, and spiral oscillation formed by arc elongation and flattening, driven by vector airflow, and arc oscillation.

[0034] Figure 5 This is a schematic diagram illustrating the process of arc elongation and flattening.

[0035] Figure 6 This is a schematic diagram illustrating the formation process of the sawtooth-shaped oscillation of the electric arc;

[0036] Figure 7 This is a schematic diagram illustrating the formation process of the rectangular oscillation of the electric arc;

[0037] Figure 8 This is a schematic diagram illustrating the formation process of the electric arc's spiral oscillation.

[0038] In the diagram: 1. Plasma welding torch; 2. Shielding gas cylinder; 3. Ionizing gas cylinder; 4. Welding power source; 5. Wire feeder; 6. Deposited layer; 7. Solenoid valve; 8. Auxiliary ionizing gas cylinder; 9. Computer control terminal; 10. Substrate;

[0039] 1-1. Tungsten electrode; 1-2. Plasma gas channel; 1-3. Auxiliary ion gas channel; 1-4. Protective gas channel; 1-5. Welding torch nozzle protective cover; 1-6. Separator ring. Detailed Implementation

[0040] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0041] like Figure 1 As shown, the plasma arc welding wire additive manufacturing device based on vector airflow-driven arc oscillation adopts a side-axis wire feeding method and includes a plasma welding torch 1, a shielding gas cylinder 2, an ion gas cylinder 3, a welding power source 4, a wire feeding device 5, a solenoid valve 7, an auxiliary ion gas cylinder 8, a computer control terminal 9, and a substrate 10.

[0042] The protective gas cylinder 2, ion gas cylinder 3, and auxiliary ion gas cylinder 8 are all connected to the plasma welding torch 1 via pipes. The welding power source 4 is electrically connected to the plasma welding torch 1. The wire feeding device 5 is fixedly connected to the plasma welding torch 1 via a connecting plate. During the arc additive manufacturing process, the heat source required for additive deposition is provided by the welding power source 4, which is electrically connected to the plasma welding torch 1. The computer control terminal 9 is electrically connected to the plasma welding torch 1 and controls the movement of the plasma welding torch 1 and the wire feeding device 5 in three dimensions. The solenoid valve 7 is connected to the auxiliary ion gas cylinder 8. The computer control terminal 9 is electrically connected to the solenoid valve 7 and uses electrical signals to control the opening and closing of the solenoid valve, thereby controlling the on / off of the auxiliary ion gas. The substrate 10 is located below the plasma welding torch 1.

[0043] like Figure 2-3As shown, the nozzle of the plasma welding torch 1 includes a tungsten electrode 1-1, a plasma gas channel 1-2, an auxiliary ion gas channel 1-3, a protective gas channel 1-4, and a welding torch nozzle protective cover 1-5. The tungsten electrode 1-1, plasma gas channel 1-2, auxiliary ion gas channel 1-3, and protective gas channel 1-4 are all located inside the welding torch nozzle protective cover 1-5. The tungsten electrode 1-1 is located at the center of the welding torch nozzle protective cover 1-5, while the plasma gas channels 1-2, auxiliary ion gas channels 1-3, and protective gas channels 1-4 are located around the tungsten electrode 1-1. Furthermore, the auxiliary ion gas channel 1-3 has four channels, evenly distributed around the circumference of the tungsten electrode 1-1. The diameter of the gas channel of the auxiliary ion gas channel 1-3 is 1 mm, and the inward reduction of the tungsten electrode 1-1 is 3 mm.

[0044] The wire feeding device 5 uses welding wire made of aluminum alloy, stainless steel, carbon steel, or titanium alloy. The ion gas cylinder 3 and auxiliary ion gas cylinder 8 contain argon or a helium-argon mixture; the protective gas cylinder 2 contains argon, helium, or a helium-argon mixture.

[0045] like Figure 3 As shown, the four auxiliary ion channels 1-3 are, respectively, channel A, channel C, channel B, and channel D in a clockwise direction. Channel A and channel B are positioned opposite each other, and channel C and channel D are positioned opposite each other. The four auxiliary ion channels 1-3 form different arc oscillation forms, including but not limited to the following four methods:

[0046] Arc stretching and flattening: such as Figure 5 As shown, in the first half of the cycle, airways A and B, which are set opposite each other, are opened, while airways C and D are closed; in the second half of the cycle, airways C and D, which are set opposite each other, are opened, while airways A and B are closed.

[0047] Arc sawtooth oscillation: such as Figure 6 As shown, in the first half of the cycle, adjacent airways A and C are opened, while airways B and D are closed; in the second half of the cycle, opposing airways B and D are opened, while airways A and C are closed.

[0048] Electric arc rectangular oscillation: such as Figure 7 As shown, the rotation period of the electric arc rectangle is divided into four equal parts: time period T1, time period T2, time period T3, and time period T4. During time period T1, airways A and C are opened, while airways B and D are closed. During time period T2, airways A, C, and D are opened, while airway B is closed. During time period T3, airways B and D are opened, while airways A and C are closed. During time period T4, airways B, C, and D are opened, while airway A is closed.

[0049] Arc spiral oscillation: such as Figure 8As shown, the period of the electric arc spiral rotation is divided into four equal parts: time period T1, time period T2, time period T3, and time period T4. During time period T1, airway A, airway C, and airway D are opened, while airway B is closed. During time period T2, airway A, airway B, and airway C are opened, while airway D is closed. During time period T3, airway B, airway C, and airway D are opened, while airway A is closed. During time period T4, airway A, airway B, and airway D are opened, while airway C is closed.

[0050] The additive manufacturing process includes the following steps:

[0051] Step 1: Fix the substrate 10 to be deposited on the additive manufacturing stage and set the flow rates of the main ion gas and the protective gas. During the additive manufacturing process, both the main ion gas and the protective gas are in the open state, and the vector arc is controlled by closing the four auxiliary ion gas channels 1-3.

[0052] Turn on the welding power supply 4, set the welding current, and use the computer control terminal 9 to control the three-dimensional motion mechanism to adjust the relative position of the plasma welding gun 1 and the substrate 10 to be deposited, so that it is located at a certain position above the substrate 10.

[0053] Step 2: Start the welding power supply 4 and the three-dimensional motion device, and control the plasma welding gun 1 to perform additive deposition according to the predetermined trajectory. During the additive process, the four auxiliary ion gases control the arc to stretch and flatten or oscillate in a sawtooth shape, a rectangular shape, or a spiral shape according to the set time and sequence.

[0054] Step 3: After deposition is completed, control the three-dimensional motion device to return the plasma welding gun 1 to its initial position and raise the plasma welding gun 1 to a certain height;

[0055] Step 4: Repeat steps 2 and 3 to perform the additive deposition cycle until the desired structural component is obtained, then end the additive process.

[0056] In summary, this invention utilizes four auxiliary ion gases to vector-control the electric arc, enabling directional movement and shape changes. This, in turn, allows for adjustments to the auxiliary ion gas flow combination, achieving different arc oscillation patterns, such as sawtooth, rectangular, and spiral oscillations. The oscillating arc stirs the molten pool and prolongs the metal solidification time, promoting bubble escape from the molten pool. This refines grains, optimizes workpiece surface quality, reduces porosity, and improves mechanical strength, thereby enhancing the microstructure and properties of additive manufacturing.

[0057] Specific usage example 1:

[0058] Taking the deposition of an aluminum alloy layer 5cm high and 8mm wide using an improved plasma arc additive manufacturing system as an example. According to... Figure 1The connection method shown completes the equipment connection. A plasma arc welding power supply is required. The computer control unit synchronizes the plasma arc welding torch and wire feeder. The specific steps are as follows:

[0059] Step 1: Fix the substrate to be deposited on the additive manufacturing stage. Set the main ion gas flow rate to 2.0 L / min and the protective gas flow rate to 15 L / min. Divide the two opposing auxiliary ion gas channels into groups A and B, and groups C and D. Set the period of the arc trapezoidal oscillation to 100 ms and divide it into two equal parts. Open channels A and B from 1 to 50 ms, open channels C and D at 51 ms and close channels A and B, and close channels C and D at 100 ms. This completes one 100 ms vector arc cycle. Repeat this cycle during the additive manufacturing process.

[0060] Turn on the plasma arc welding power supply and set the welding current to 100A. Use a computer-controlled three-dimensional motion mechanism to adjust the relative position of the plasma welding torch and the aluminum plate to be deposited, positioning it 3mm above the aluminum plate.

[0061] Step 2: Start the plasma welding power supply and three-dimensional motion device, and control them to carry out the additive deposition process according to the predetermined trajectory. During the additive process, four auxiliary ion gases circulate according to the cycle of Step 1.

[0062] Step 3: After deposition is complete, control the three-dimensional motion device to return the welding torch to its initial position and raise the height of the welding torch by 3mm.

[0063] Step 4: Repeat steps 2 and 3 to perform the additive deposition cycle until the desired structural component is obtained, then end the additive process.

[0064] Specific usage example 2:

[0065] Taking the deposition of an aluminum alloy layer 5cm high and 8mm wide using an improved plasma arc additive manufacturing system as an example. According to... Figure 1 The connection method shown completes the equipment connection. A plasma arc welding power supply is required. The computer control unit synchronizes the plasma arc welding torch and wire feeder. The specific steps are as follows:

[0066] Step 1: Fix the substrate to be deposited on the additive manufacturing stage. Set the main ion gas flow rate to 2.0 L / min and the protective gas flow rate to 15 L / min. During the additive manufacturing process, both the main ion gas and the protective gas are on. Set the arc spiral rotation period to 100 ms and divide it into 4 equal segments. Starting at 1 ms, introduce 1.0 L / min of ion gas into the three auxiliary ion gas channels A, C, and D. At 26 ms, close channel D, keeping channels A and C open, and simultaneously introduce 1.0 L / min of ion gas into channel B. At 51 ms, close channel A, keeping channels B and C open, and simultaneously introduce 1.0 L / min of ion gas into channel D. At 76 ms, close channel C, keeping channels B and D open, and simultaneously introduce 1.0 L / min of ion gas into channel A. At 100 ms, close channels A, B, and D, completing one 100 ms vector arc cycle. Repeat this cycle during the additive manufacturing process.

[0067] Turn on the plasma arc welding power supply and set the welding current to 100A. Use a computer-controlled three-dimensional motion mechanism to adjust the relative position of the plasma welding torch and the aluminum plate to be deposited, positioning it 3mm above the aluminum plate.

[0068] Step 2: Start the plasma welding power supply and three-dimensional motion device, and control them to carry out the additive deposition process according to the predetermined trajectory. During the additive process, four auxiliary ion gases circulate according to the cycle of Step 1.

[0069] Step 3: After deposition is complete, control the three-dimensional motion device to return the welding torch to its initial position and raise the height of the welding torch by 3mm.

[0070] Step 4: Repeat steps 2 and 3 to perform the additive deposition cycle until the desired structural component is obtained, then end the additive process.

[0071] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for additive manufacturing using a plasma arc fuse additive manufacturing device based on vector airflow-driven arc oscillation, characterized in that, The plasma arc welding wire additive manufacturing device includes a plasma welding torch (1), a shielding gas cylinder (2), an ion gas cylinder (3), a welding power source (4), a wire feeding device (5), a solenoid valve (7), an auxiliary ion gas cylinder (8), a computer control terminal (9), and a substrate (10); wire feeding is performed using a side-axis wire feeding method; the shielding gas cylinder (2), the ion gas cylinder (3), and the auxiliary ion gas cylinder (8) are all connected to the plasma welding torch (1) through pipes, the welding power source (4) is electrically connected to the plasma welding torch (1), and the wire feeding device (5) The heat source required for additive deposition during the arc additive manufacturing process is provided by the welding power supply (4) which is electrically connected to the plasma welding gun (1) via a connecting plate; the computer control terminal (9) is electrically connected to the plasma welding gun (1) to control the movement of the plasma welding gun (1) and the wire feeding device (5) in three dimensions; the solenoid valve (7) is connected to the auxiliary ion gas cylinder (8); the computer control terminal (9) is electrically connected to the solenoid valve (7) to control the opening and closing of the solenoid valve with an electrical signal, thereby controlling the on / off state of the auxiliary ion gas. The substrate (10) is positioned below the plasma welding torch (1); the nozzle of the plasma welding torch (1) includes a tungsten electrode (1-1), a plasma gas channel (1-2), an auxiliary ion gas channel (1-3), a protective gas channel (1-4), and a welding torch nozzle protective cover (1-5). The tungsten electrode (1-1), plasma gas channel (1-2), auxiliary ion gas channel (1-3), and protective gas channel (1-4) are all located inside the welding torch nozzle protective cover (1-5), and the tungsten electrode (1-1) is located at the center of the welding torch nozzle protective cover (1-5). The plasma gas channel (1-2), auxiliary ion gas channel (1-3), and protective gas channel (1-4) are arranged around the tungsten electrode (1-1). The auxiliary ion gas channel (1-3) has four channels, evenly arranged around the circumference of the tungsten electrode (1-1). The four auxiliary ion gas channels (1-3) are, respectively, channel A, channel C, channel B, and channel D in a clockwise direction. Channel A and channel B are positioned opposite each other, and channel C and channel D are positioned opposite each other. The four auxiliary ion gas channels (1-3) form different arc oscillation forms in the following four ways:

1. Arc stretching and flattening: In the first half of the cycle, open the opposing airways A and B, and close the airways C and D; in the second half of the cycle, open the opposing airways C and D, and close the airways A and B.

2. Arc sawtooth oscillation: In the first half of the cycle, adjacent airways A and C are opened, while airways B and D are closed; in the second half of the cycle, opposing airways B and D are opened, while airways A and C are closed.

3. Arc Rectangular Oscillation: Divide the rotation period of the arc rectangle into four equal parts, namely time period T1, time period T2, time period T3, and time period T4; during time period T1, open airway A and airway C, and close airway B and airway D. During time period T2, airway A, airway C, and airway D are opened, while airway B is closed. During time period T3, airway B and airway D are opened, while airway A and airway C are closed. During time period T4, airway B, airway C, and airway D are opened, while airway A is closed. IV. Arc Spiral Oscillation: Divide the period of the arc spiral rotation into four equal parts, namely the time period T1, T2, T3, and T4. During time period T1, airway A, airway C, and airway D are opened, and airway B is closed; during time period T2, airway A, airway B, and airway C are opened, and airway D is closed. During time period T3, airway B, airway C, and airway D are opened, while airway A is closed. During time period T4, airway A, airway B, and airway D are opened, while airway C is closed. The method includes the following steps: Step 1: Fix the substrate (10) to be deposited on the additive manufacturing stage and set the flow rates of the main ion gas and the protective gas. During the additive manufacturing process, both the main ion gas and the protective gas are in the open state, and the vector arc is controlled by closing the four auxiliary ion gas channels (1-3). Turn on the welding power supply (4), set the welding current, and use the computer control terminal (9) to control the three-dimensional motion mechanism to adjust the relative position of the plasma welding gun (1) and the substrate to be deposited (10) so that it is located at a certain position above the substrate (10). Step 2: Start the welding power supply (4) and the three-dimensional motion device, and control the plasma welding gun (1) to perform additive deposition according to the predetermined trajectory. During the additive process, the four auxiliary ion gases control the arc to stretch and flatten or swing in a sawtooth shape or a rectangular shape or a spiral shape according to the set time and sequence. Step 3: After the deposition is completed, control the three-dimensional motion device to return the plasma welding gun (1) to the initial position and raise the plasma welding gun (1) to a certain height; Step 4: Repeat steps 2 and 3 to perform the additive deposition cycle until the desired structural component is obtained, then end the additive process.

2. The method according to claim 1, characterized in that, The diameter of the gas passage of the auxiliary ion gas channel (1-3) is 1 mm, and the inward shrinkage of the tungsten electrode (1-1) is 3 mm.

3. The method according to claim 1, characterized in that, The welding wire used in the wire feeding device (5) is made of aluminum alloy, stainless steel, carbon steel, or titanium alloy.

4. The method according to claim 1, characterized in that, The gas in the ion gas cylinder (3) and the auxiliary ion gas cylinder (8) is argon or a mixture of helium and argon; the gas in the protective gas cylinder (2) is argon, helium or a mixture of helium and argon.

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