Solid tungsten electrode negative pressure arc plasma beam cleaning and processing method

Abstract

The invention provides a solid tungsten electrode negative pressure arc plasma beam cleaning machining method. The method comprises the steps of adjusting technological parameters, forming negative pressure arc plasma beam rotary adsorption cleaning, negative pressure arc fixed-point cleaning and online monitoring and adjusting. Through the steps, different cleaning parameters are selected according to different cleaning materials, and dynamic anti-gravity, upward negative pressure and an influence area thereof are formed in an electric arc action area by utilizing a magnetic field through the synergistic effect of negative pressure electric arc plasma beam rotary adsorption cleaning and electric arc cleaning technology for regulating and controlling magnetic field threshold constraint; and the oxidation film or pollutants are directionally stripped and upwards migrated to a collecting device, so that the removal is achieved, and meanwhile, high-energy fixed-point cleaning of arc cathode spots is combined, so that high-efficiency, high-precision and wider-cleaning-range surface cleaning treatment is realized.

Description

Technical Field

[0001] The invention relates to the field of arc cleaning, and in particular to a solid tungsten electrode negative pressure arc plasma beam cleaning processing method. Background Art

[0002] Arc cleaning technology, a novel cleaning method used in welding and additive manufacturing processes, is divided into two phases based on arc polarity configuration: EP (Electrode Positive) and EN (Electrode Negative). The difference between the two is that in the EP phase, the tungsten electrode is connected to the positive power supply and the workpiece or base material to the negative power supply. In this phase, electrons flow from the workpiece (cathode) to the electrode (anode), creating a cathode spot effect. When electrons strike the workpiece surface, they produce high-energy cathode spots, which preferentially target the oxide film (because the work function of the oxide film is lower than that of pure metal), removing the oxide through evaporation or exfoliation. In the EN phase, electrons flow in the opposite direction, from the electrode (cathode) to the workpiece (anode). This shift in electron flow concentrates most of the heat in the EP phase on the electrode, leaving a smaller amount on the workpiece, minimizing thermal damage. This makes the EN phase more suitable for high-precision cleaning, such as targeted oxide film removal. In the EN phase, the majority of the heat is concentrated on the workpiece, making it more suitable for assisting melting or welding. Therefore, the EN phase is more stable and suitable for continuous processing.

[0003] Traditional arc cleaning technology uses the cathode spot effect in the EP stage to achieve fixed-point cleaning. However, this arc cleaning technology has certain limitations: (1) Cleaning is highly random: The movement of the cathode spot is irregular. When there is an oxide film and stains in the form of a pavement and the cleaning surface is a complex surface, the cleaning effect of the cathode spot is random and unsatisfactory; (2) Cleaning efficiency is difficult to improve: Under the premise of not causing the surface of the parent material or the workpiece to melt and not burning out the tungsten electrode, the EP current has an upper limit on the improvement of the cleaning efficiency, and it is impossible to further improve the cleaning efficiency by increasing the EP current. (3) Cleaning object is single: The cleaning object is often only for conductors, and the cleaning effect for non-conductors needs to be improved. Therefore, when facing complex surface cleaning, using a single arc cleaning method is prone to incomplete cleaning.

[0004] In view of this, the present invention proposes a solid tungsten electrode negative pressure arc plasma beam cleaning method to solve the above problems. Summary of the Invention

[0005] In order to solve the above problems, the purpose of the present invention is to propose a solid tungsten electrode negative pressure arc plasma beam cleaning processing method, select different cleaning parameters for different cleaning materials, and coordinate the negative pressure arc plasma beam rotation adsorption cleaning and arc cleaning technology by regulating the magnetic field threshold constraint. The magnetic field is used to form dynamic anti-gravity, upward negative pressure and its affected area in the arc action area, so as to directionally peel off the oxide film or contaminants and migrate upward to the collection device, thereby achieving removal. At the same time, combined with the high-energy fixed-point cleaning of the arc cathode spots, efficient and high-precision surface cleaning processing is achieved.

[0006] The above purpose is achieved through the following technical solutions:

[0007] A solid tungsten electrode negative pressure arc plasma beam cleaning method comprises the following steps:

[0008] Step 1: Adjusting process parameters: Adjusting arc parameters to match magnetic field parameters, the arc current is 30-280A, the solid tungsten electrode is connected to the negative pole of the power supply, and the parent material or workpiece is connected to the positive pole of the power supply, which is the electrode positive connection (EP) stage; the tungsten electrode is connected to the positive pole of the power supply, and the parent material or workpiece is connected to the negative pole of the power supply, which is the electrode reverse connection (EN) stage; the electrode positive connection (EP) stage accounts for 10% to 70%, and the current frequency is 10-10000 Hz; the magnetic field strength is 0.022-0.5T, and the magnetic field frequency is 2-100kHz. Combined with the arc cleaning process parameters, the magnetic field strength is greater than the critical value required to be set under the arc negative pressure constraint cleaning process conditions, and the magnetic field strength greater than the critical value is used as the target magnetic field strength, and the target magnetic field strength is greater than 0.022T;

[0009] Step 2: Forming a negative pressure arc plasma beam for rotating adsorption cleaning: Applying a target magnetic field strength to the solid tungsten arc area to form an anti-gravity, upward negative pressure of -6 to -620 Pa at the center of the solid tungsten arc and its affected area. The diameter of the solid tungsten arc's affected area is 0.6 to 14 mm, generating a rotating negative pressure adsorption force constrained by the magnetic field, causing the oxide film or contaminants to peel off and migrate upward to the collection device, thereby achieving removal. The cleaning speed is 10 to 900 mm / min, and the appropriate process parameters are selected according to different materials.

[0010] Alternatively, you can choose negative pressure arc spot cleaning: remove oxide film or contaminants through arc cathode spot direction;

[0011] Step 3: Online monitoring and adjustment: Use a high-speed spectrometer and a Hall sensor to monitor the magnetic field distribution and the particle composition in the arc area in real time, and feedback control the magnetic field intensity and arc energy to ensure high adsorption rate and good surface quality.

[0012] Furthermore, the negative pressure arc magnetic field threshold and arc current of the solid tungsten electrode negative pressure arc plasma beam cleaning method satisfy the following functional relationship:

[0013] B(I)=0.018+3.35×10 -5 I+1.25×10 -7 I 2

[0014] Where: B represents the magnetic field strength threshold, the unit is Tesla (T), I represents the arc current, the unit is Ampere (A);

[0015] Furthermore, the magnetic field in step 1 is formed by setting a powered coil to form a longitudinal magnetic field in which the center line of the magnetic field is parallel to or coincides with the center line of the arc, and the external longitudinal magnetic field mode is a continuous alternating magnetic field mode, an intermittent alternating magnetic field mode, or a pulsed alternating magnetic field mode; the external longitudinal magnetic field mode is a fixed longitudinal magnetic field mode, a rotating longitudinal magnetic field mode, a longitudinal dual magnetic field mode with reversed inside and outside directions, or a longitudinal dual magnetic field mode with reversed top and bottom directions;

[0016] Furthermore, the negative pressure arc area in step 2 is always within the gas protection range during operation to avoid secondary oxidation after cleaning. The protective gas type is 100% argon, or 100% helium, or a quaternary mixed gas of argon + helium as the main body + 0.01% hydrogen + 0.01% oxygen, or a ternary mixed gas of argon + helium as the main body + 0.01% oxygen, or a binary mixed gas of argon + helium, and the protective gas flow rate is 5 to 40 L / min;

[0017] Furthermore, the negative pressure arc adsorption force in step 2 is a relative pressure based on atmospheric pressure, and is the sum of the arc forces in an upward direction at a standard horizontal position, which is opposite to the direction of gravity;

[0018] Furthermore, the collecting device in step 2 includes an electrostatic adsorption plate and a magnetic shielding layer, the voltage of the electrostatic adsorption plate is 2 to 15V, and the magnetic shielding layer is made of Permalloy material with a thickness of 0.1 to 0.5 mm;

[0019] Furthermore, the method is applicable to aluminum alloy materials, magnesium alloy materials, titanium alloy materials, or steel materials; the cleaning objects include conductive pollutants and non-conductive pollutants;

[0020] Furthermore, the material is 7075 aluminum alloy, and the process parameters are: 100% argon protection, argon flow rate 5-25 L / min, arc current 45 A, electrode positive (EP) stage accounting for 10%-50%, current frequency 10-5000 Hz, arc length 2-4 mm, tungsten electrode diameter 3 mm, arc voltage 14.5 V, the critical value of the applied longitudinal magnetic field strength is 0.022 T, the applied longitudinal magnetic field strength is 0.023-0.04 T, the negative pressure value range is -6--120 Pa, the negative pressure arc adsorption force is generated, the diameter of the negative pressure arc affected area is 0.6-3 mm, the magnetic field frequency is 50 kHz, the duty cycle is 25%, and the cleaning speed is 10-300 mm / min;

[0021] Furthermore, the material is TC4, and the process parameters are: 100% argon protection, argon flow rate 8-30 L / min, arc current 150 A, electrode positive (EP) stage accounting for 40%-60%, current frequency 3000-6000 Hz, arc length 2-4 mm, tungsten electrode diameter 3 mm, arc voltage 21.4 V, the critical value of the applied longitudinal magnetic field strength is 0.025 T, the applied longitudinal magnetic field strength is 0.026-0.08 T, and the negative pressure value range is -10--320 Pa. The negative pressure arc adsorption force is generated, the diameter of the negative pressure arc affected area is 0.8-6 mm, the magnetic field frequency is 50 kHz, the duty cycle is 25%, and the cleaning speed is 100-500 mm / min;

[0022] Furthermore, the material is Q345, and the process parameters are: 100% argon protection, argon flow rate 12~40L / min, arc current 280A, electrode positive (EP) stage accounts for 50%~70%, current frequency is 5000~10000Hz, arc length 2~4mm, tungsten pole diameter 3mm, arc voltage 25V, the critical value of the applied longitudinal magnetic field strength is 0.03T, the applied longitudinal magnetic field strength is 0.1~0.5T, and the negative pressure value range is -400~-620Pa. The negative pressure arc adsorption force, the diameter of the negative pressure arc affected area is 6~14mm, the magnetic field frequency is 60kHz, the duty cycle is 25%, and the cleaning speed is 500~900mm / min.

[0023] The present invention has the following beneficial effects: Different cleaning parameters are selected for different cleaning materials. By regulating the magnetic field threshold constraint, the negative pressure arc plasma beam rotation adsorption cleaning works in synergy with the arc cleaning technology. The magnetic field creates dynamic anti-gravity and upward negative pressure in the arc action area and its affected area, which directionally peels off the oxide film or contaminants and migrates upward to the collection device, thereby achieving removal. Simultaneously, combined with high-energy, targeted cleaning of the arc cathode spot, efficient and high-precision surface cleaning is achieved. This extends the cleaning range and covers both conductive and non-conductive materials.

[0024] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings and in conjunction with the embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a working schematic diagram of the present invention;

[0026] Figure 2 yes Figure 1 Detailed view of point A;

[0027] Figure 3 This is the negative pressure arc plasma beam flow field of the present invention. In the figure, the currents (a)-(f) are (a) 160A, (b) 180A, (c) 200A, (d) 220A, (e) 240A, and (f) 260A respectively.

[0028] Figure numerals: 1 base material or workpiece; 2 oxide film or contaminant; 3 solid tungsten pole; 4 arc area; 5 negative pressure area; 6 magnetic field; 7 power supply; 8 collecting device; 801 magnetic shielding layer; 802 electrostatic adsorption plate; 9 high-speed spectrometer and Hall sensor. DETAILED DESCRIPTION

[0029] The following embodiments of the present invention are described in further detail with reference to the accompanying drawings and examples. The following examples are used to illustrate the present invention but are not intended to limit the scope of the present invention.

[0030] In the description of the present invention, unless otherwise specified, "plurality" means two or more; terms such as "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," and "tail" indicate positions or relationships based on those shown in the accompanying drawings. These terms are intended solely to facilitate the description of the present invention and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limiting the present invention. Furthermore, terms such as "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0031] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "connected" and "connection" should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integral connection; mechanical connection, electrical connection; direct connection, or indirect connection through an intermediary. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0032] The following combination Figures 1-2 The present invention provides a solid tungsten electrode negative pressure arc plasma beam cleaning method, which includes the following steps:

[0033] Step 1: Adjusting process parameters: Adjusting arc parameters to match magnetic field parameters, the arc current is 30-280A, the solid tungsten electrode is connected to the negative pole of the power supply, and the parent material or workpiece is connected to the positive pole of the power supply, which is the electrode positive connection (EP) stage; the tungsten electrode is connected to the positive pole of the power supply, and the parent material or workpiece is connected to the negative pole of the power supply, which is the electrode reverse connection (EN) stage; the electrode positive connection (EP) stage accounts for 30%-70%, the current frequency is 10-10000 Hz; the magnetic field strength is 0.022-0.5T, and the magnetic field frequency is 2-100kHz. Combined with the arc cleaning process parameters, the magnetic field strength is greater than the critical value required to be set under the arc negative pressure constraint cleaning process conditions, and the magnetic field strength greater than the critical value is used as the target magnetic field strength, and the target magnetic field strength is greater than 0.022T;

[0034] Step 2: Forming a negative pressure arc plasma beam for rotating adsorption cleaning: Applying a target magnetic field strength to the solid tungsten arc area to form an anti-gravity, upward negative pressure arc adsorption force of -6 to -620 Pa at the center of the solid tungsten arc and its affected area. The diameter of the solid tungsten arc affected area is 0.6 to 14 mm, generating a rotating negative pressure adsorption force constrained by the magnetic field, causing the oxide film or contaminants to peel off and migrate upward to the collection device, thereby achieving removal. The cleaning speed is 10 to 900 mm / min, and the appropriate process parameters are selected according to different materials.

[0035] Alternatively, you can choose negative pressure arc spot cleaning: remove oxide film or contaminants through arc cathode spot direction;

[0036] Step 3: Online monitoring and adjustment: Use a high-speed spectrometer and a Hall sensor to monitor the magnetic field distribution and the particle composition in the arc area in real time, and feedback control the magnetic field intensity and arc energy to ensure high adsorption rate and good surface quality.

[0037] More specific embodiments are as follows:

[0038] The magnetic field in step 1 is formed by setting an energized coil to form a longitudinal magnetic field in which the center line of the magnetic field is parallel to or coincides with the center line of the arc. The external longitudinal magnetic field mode is a continuous alternating magnetic field mode, an intermittent alternating magnetic field mode, or a pulsed alternating magnetic field mode; the external longitudinal magnetic field mode is a fixed longitudinal magnetic field mode, a rotating longitudinal magnetic field mode, a longitudinal dual magnetic field mode with reversed inside and outside, or a longitudinal dual magnetic field mode with reversed top and bottom.

[0039] The negative pressure arc area in step 2 is always within the gas protection range during operation to avoid secondary oxidation after cleaning. The protective gas type is 100% argon, or 100% helium, or a quaternary mixed gas with argon + helium as the main body + 0.01% hydrogen + 0.01% oxygen, or a ternary mixed gas with argon + helium as the main body + 0.01% oxygen, or a binary mixed gas of argon + helium, and the protective gas flow rate is 5 to 40 L / min.

[0040] The negative pressure arc adsorption force in step 2 is a relative pressure based on atmospheric pressure, and is the sum of the arc forces in an upward direction at a standard horizontal position, which is opposite to the direction of gravity.

[0041] The collecting device includes an electrostatic adsorption plate and a magnetic shielding layer. The voltage of the electrostatic adsorption plate is 2 to 15V. The magnetic shielding layer is made of Permalloy material with a thickness of 0.1 to 0.5mm. The electrostatic adsorption plate is arranged in the inner layer and the magnetic shielding layer is the outer layer.

[0042] The method is applicable to aluminum alloy materials, magnesium alloy materials, titanium alloy materials, or steel materials; the cleaning objects include conductive pollutants and non-conductive pollutants, and is particularly applicable to ultra-clean processing of microelectronic components, medical equipment, and aerospace aluminum alloy parts.

[0043] Example 1:

[0044] The negative pressure arc plasma beam cleaning method for the 7075 aluminum alloy anodic oxide film of this embodiment specifically includes the following steps:

[0045] Step 1: Adjust the process parameters: adjust the arc parameters to match the magnetic field parameters, connect the 7075 aluminum alloy base material to the positive pole of the power supply, connect the solid tungsten electrode to the negative pole of the power supply, the arc length is 2-4 mm, the tungsten electrode diameter is 3 mm, the arc voltage is 14.5 V, the base material thickness is 20 mm, and the distance between the tungsten electrode and the base material is 5.5 mm. Adjust the power supply EN stage current amplitude to 30 A (in order to maintain continuous arc function and minimize heat input during the cleaning stage, the EN current intensity is kept at a low level of 30 A), the EP stage current amplitude is 45 A, the EP stage accounts for 10% to 50%, the frequency is 50 Hz, and the current waveform is rectangular; the external longitudinal magnetic field mode is uniformly distributed continuous alternation, and the magnetic field mode is a fixed longitudinal magnetic field mode; the critical value of the external longitudinal magnetic field intensity is 0.022 T, the external longitudinal magnetic field intensity is 0.023 to 0.04 T, the magnetic field frequency is 50 kHz, the duty cycle is 25%, and the cleaning speed is 10 to 300 mm / min;

[0046] Step 2: Forming a negative pressure arc plasma beam for rotating adsorption cleaning: applying a target magnetic field strength in the solid tungsten pole arc area to form a negative pressure arc adsorption force in the direction of anti-gravity at the center of the solid tungsten pole arc. The negative pressure value range is -6 to -120 Pa, and the diameter of the negative pressure arc affected area is 0.6 to 3 mm, so that the anodized film is peeled off and migrated upward to the collection device, thereby achieving removal. The cleaning speed is 270 mm / min, the voltage of the electrostatic adsorption plate in the collection device is 8 V, and the magnetic shielding layer is made of Permalloy material with a thickness of 0.3 mm. The type of protective gas is 100% argon, and the argon flow rate is 5 to 25 L / min.

[0047] Alternatively, you can choose negative pressure arc spot cleaning: remove oxide film or contaminants through arc cathode spot direction;

[0048] Step 3: Online monitoring and adjustment: Use a high-speed spectrometer and a Hall sensor to monitor the magnetic field distribution and the particle composition in the arc area in real time, and feedback control the magnetic field intensity and arc energy to ensure high adsorption rate and good surface quality.

[0049] Through the above steps, the roughness is reduced by 10% to 30% compared with the traditional arc cleaning surface.

[0050] Example 2:

[0051] The negative pressure arc plasma beam cleaning method for the TC4 oxide film of this embodiment specifically includes the following steps:

[0052] Step 1: Adjust the process parameters: adjust the arc parameters to match the magnetic field parameters, connect the TC4 base material to the positive pole of the power supply, connect the solid tungsten electrode to the negative pole of the power supply, the arc length is 2-4 mm, the tungsten electrode diameter is 3 mm, the arc voltage is 21.4 V, the base material thickness is 20 mm, and the distance between the tungsten electrode and the base material is 6 mm. Adjust the power supply EN stage current amplitude to 30 A (in order to maintain continuous arc function and minimize heat input during the cleaning stage, the EN current intensity is kept at a low level of 30 A), the EP stage current amplitude is 150 A, the EP stage accounts for 40% to 60%, the frequency is 50 Hz, and the current waveform is rectangular; the external longitudinal magnetic field mode is uniformly distributed continuous alternating, and the magnetic field mode is a fixed longitudinal magnetic field mode; the critical value of the external longitudinal magnetic field intensity is 0.025 T, the external longitudinal magnetic field intensity is 0.026-0.08 T, the magnetic field frequency is 50 kHz, the duty cycle is 25%, and the cleaning speed is 100-500 mm / min;

[0053] Step 2: Forming a negative pressure arc plasma beam for rotating adsorption cleaning: applying a target magnetic field strength in the solid tungsten pole arc area to form a negative pressure arc adsorption force in the anti-gravity direction at the center of the solid tungsten pole arc. The negative pressure value range is -10 to -320 Pa. The diameter of the negative pressure arc affected area is 0.8 to 6 mm, causing the oxide film to peel off and migrate upward to the collection device, thereby achieving removal. The cleaning speed is 400 mm / min. The voltage of the electrostatic adsorption plate in the collection device is 10 V. The magnetic shielding layer is made of Permalloy material with a thickness of 0.3 mm. The type of protective gas is 100% argon, and the argon flow rate is 8 to 30 L / min.

[0054] Alternatively, you can choose negative pressure arc spot cleaning: the oxide film is removed by arc cathode spot direction;

[0055] Step 3: Online monitoring and adjustment: Use a high-speed spectrometer and a Hall sensor to monitor the magnetic field distribution and the particle composition in the arc area in real time, and feedback control the magnetic field intensity and arc energy to ensure high adsorption rate and good surface quality.

[0056] Through the above steps, the roughness is reduced by 15% to 25% compared with the traditional arc cleaning surface.

[0057] Example 3:

[0058] The negative pressure arc plasma beam cleaning method for the Q345 oxide film of this embodiment specifically includes the following steps:

[0059] Step 1: Adjust the process parameters: adjust the arc parameters to match the magnetic field parameters, connect the Q345 base material to the positive pole of the power supply, connect the solid tungsten electrode to the negative pole of the power supply, the arc length is 2-4 mm, the tungsten electrode diameter is 3 mm, the arc voltage is 25 V, the base material thickness is 1 mm, and the distance between the tungsten electrode and the base material is 8 mm. Adjust the power supply EN stage current amplitude to 30 A (in order to maintain continuous arc function and minimize heat input during the cleaning stage, the EN current intensity is kept at a low level of 30 A), the EP stage current amplitude is 280 A, the EP stage accounts for 50% to 70%, the frequency is 50 Hz, and the current waveform is rectangular; the external longitudinal magnetic field mode is uniformly distributed continuous alternating, and the magnetic field mode is a fixed longitudinal magnetic field mode; the critical value of the external longitudinal magnetic field intensity is 0.03 T, the external longitudinal magnetic field intensity is 0.1 to 0.5 T, the magnetic field frequency is 60 kHz, the duty cycle is 25%, and the cleaning speed is 500 to 900 mm / min;

[0060] Step 2: Forming a negative pressure arc plasma beam for rotating adsorption cleaning: Applying a target magnetic field strength to the solid tungsten pole arc area to form a negative pressure arc adsorption force in the anti-gravity direction in the arc center area. The negative pressure value range is -400 to -620 Pa. The diameter of the negative pressure arc affected area is 6 to 14 mm, causing the oxide film to peel off and migrate upward to the collection device, thereby achieving removal. The cleaning speed is 800 mm / min. The voltage of the electrostatic adsorption plate in the collection device is 12 V. The magnetic shielding layer is made of Permalloy material with a thickness of 0.3 mm. The protective gas type is 100% argon, and the argon flow rate is 12 to 40 L / min.

[0061] Alternatively, you can choose negative pressure arc spot cleaning: the oxide film is removed by arc cathode spot direction;

[0062] Step 3: Online monitoring and adjustment: Use a high-speed spectrometer and a Hall sensor to monitor the magnetic field distribution and the particle composition in the arc area in real time, and feedback control the magnetic field intensity and arc energy to ensure high adsorption rate and good surface quality.

[0063] Through the above steps, the roughness is reduced by 15% to 20% compared with the traditional arc cleaning surface.

[0064] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not limiting. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the purpose and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A solid tungsten electrode negative pressure arc plasma beam cleaning method, characterized in that: The following steps are involved: Step 1: Adjusting process parameters: Adjusting arc parameters to match magnetic field parameters, the arc current is 30-280A, the solid tungsten electrode is connected to the negative pole of the power supply, and the parent material or workpiece is connected to the positive pole of the power supply, which is the electrode positive connection (EP) stage; the solid tungsten electrode is connected to the positive pole of the power supply, and the parent material or workpiece is connected to the negative pole of the power supply, which is the electrode reverse connection (EN) stage; the electrode positive connection (EP) stage accounts for 10% to 70%, and the current frequency is 10-10000 Hz; the magnetic field strength is 0.022-0.5T, and the magnetic field frequency is 2-100kHz. Combined with the arc cleaning process parameters, the magnetic field strength is greater than the critical value required to be set under the arc negative pressure constraint cleaning process conditions, and the magnetic field strength greater than the critical value is used as the target magnetic field strength, and the target magnetic field strength is greater than 0.022T; Step 2: Forming a negative pressure arc plasma beam for rotating adsorption cleaning: Applying a target magnetic field strength to the solid tungsten arc area to form an anti-gravity, upward negative pressure arc adsorption force of -6 to -620 Pa at the center of the solid tungsten arc and its affected area. The diameter of the solid tungsten arc affected area is 0.6 to 14 mm, generating a rotating negative pressure adsorption force constrained by the magnetic field, causing the oxide film or contaminants to peel off and migrate upward to the collection device, thereby achieving removal. The cleaning speed is 10 to 900 mm / min, and the appropriate process parameters are selected according to different materials. Alternatively, you can choose negative pressure arc spot cleaning: remove oxide film or contaminants through arc cathode spot direction; Step 3: Online monitoring and adjustment: The magnetic field distribution and the particle composition in the arc area are monitored in real time using a high-speed spectrometer and a Hall sensor, respectively. The magnetic field intensity and arc energy are controlled by feedback to ensure high adsorption rate and good surface quality. The negative pressure arc magnetic field threshold and the arc current satisfy the following functional relationship: B(I)=0.018+3.35×10 -5 ·I+1.25×10 -7 ·I 2 Where: B represents the magnetic field strength threshold, the unit is Tesla (T), I represents the arc current, the unit is Ampere (A).

2. The solid tungsten electrode negative pressure arc plasma beam cleaning method according to claim 1, characterized in that: The magnetic field in step 1 is formed by setting an energized coil to form a longitudinal magnetic field in which the center line of the magnetic field is parallel to or coincides with the center line of the arc. The external longitudinal magnetic field mode is a continuous alternating magnetic field mode, an intermittent alternating magnetic field mode, or a pulsed alternating magnetic field mode; the external longitudinal magnetic field mode is a fixed longitudinal magnetic field mode, a rotating longitudinal magnetic field mode, a longitudinal dual magnetic field mode with reversed inside and outside, or a longitudinal dual magnetic field mode with reversed top and bottom.

3. The solid tungsten electrode negative pressure arc plasma beam cleaning method according to claim 1, characterized in that: The negative pressure arc area in step 2 is always within the gas protection range during operation to avoid secondary oxidation after cleaning. The protective gas type is 100% argon, or 100% helium, or a quaternary mixed gas with argon + helium as the main body + 0.01% hydrogen + 0.01% oxygen, or a ternary mixed gas with argon + helium as the main body + 0.01% oxygen, or a binary mixed gas of argon + helium, and the protective gas flow rate is 5 to 40 L / min.

4. The solid tungsten electrode negative pressure arc plasma beam cleaning method according to claim 1, characterized in that: The negative pressure arc adsorption force in step 2 is a relative pressure based on atmospheric pressure, and is the sum of the arc forces in an upward direction at a standard horizontal position, which is opposite to the direction of gravity.

5. The solid tungsten electrode negative pressure arc plasma beam cleaning method according to claim 1, characterized in that: The collecting device in step 2 includes an electrostatic adsorption plate and a magnetic shielding layer. The voltage of the electrostatic adsorption plate is 2 to 15V. The magnetic shielding layer is made of Permalloy material with a thickness of 0.1 to 0.5 mm.

6. The solid tungsten electrode negative pressure arc plasma beam cleaning method according to claim 1, characterized in that: The method is applicable to aluminum alloy materials, magnesium alloy materials, titanium alloy materials, or steel materials; the cleaning objects include conductive pollutants and non-conductive pollutants.

7. The solid tungsten electrode negative pressure arc plasma beam cleaning method according to claim 1, characterized in that: The material is 7075 aluminum alloy, and the process parameters are: 100% argon protection, argon flow rate 5~25L / min, arc current 45A, electrode positive (EP) stage accounts for 10%~50%, current frequency is 10~5000Hz, arc length is 2~4mm, tungsten pole diameter is 3mm, arc voltage is 14.5V, the critical value of the applied longitudinal magnetic field strength is 0.022T, the applied longitudinal magnetic field strength is 0.023~0.04T, and the negative pressure value range is -6~-120Pa. The negative pressure arc adsorption force is generated, the diameter of the negative pressure arc affected area is 0.6~3mm, the magnetic field frequency is 50kHz, the duty cycle is 25%, and the cleaning speed is 10~300mm / min.

8. The solid tungsten electrode negative pressure arc plasma beam cleaning method according to claim 1, characterized in that: The material is TC4, and the process parameters are: 100% argon protection, argon flow rate 8~30L / min, arc current 150A, electrode positive (EP) stage accounts for 40%~60%, current frequency is 3000~6000Hz, arc length is 2~4mm, tungsten pole diameter is 3mm, arc voltage is 21.4V, the critical value of the applied longitudinal magnetic field strength is 0.025T, the applied longitudinal magnetic field strength is 0.026~0.08T, and the negative pressure value range is -10~-320Pa. The negative pressure arc adsorption force is generated, the diameter of the negative pressure arc affected area is 0.8~6mm, the magnetic field frequency is 50kHz, the duty cycle is 25%, and the cleaning speed is 100~500mm / min.

9. The solid tungsten electrode negative pressure arc plasma beam cleaning method according to claim 1, characterized in that: The material is Q345, and the process parameters are: 100% argon protection, argon flow rate 12~40L / min, arc current 280A, electrode positive (EP) stage accounts for 50%~70%, current frequency is 5000~10000Hz, arc length 2~4mm, tungsten pole diameter 3mm, arc voltage 25V, the critical value of the applied longitudinal magnetic field strength is 0.03T, the applied longitudinal magnetic field strength is 0.1~0.5T, and the negative pressure value range is -400~-620Pa. The negative pressure arc adsorption force, the diameter of the negative pressure arc affected area is 6~14mm, the magnetic field frequency is 60kHz, the duty cycle is 25%, and the cleaning speed is 500~900mm / min.

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