Electrolytic plasma polishing method based on pulse high voltage assistance

Abstract

The invention discloses an electrolytic plasma polishing method based on pulse high-voltage assistance, and relates to the field of surface finishing of metal material components. The problems that the polishing effect of current electrolyte plasma polishing machining on high-surface-roughness components is limited, and the polishing uniformity of special-shaped structures is poor are solved. The energy input of the whole system in the polishing process can be improved through pulse high voltage assistance, then a thick gas film is formed on the surface of a workpiece, joule heat and gas generated by electrolytic reaction can form a high-resistance gas film on the surface of the workpiece, the high-resistance gas film can be broken down by the applied pulse high voltage to generate high-temperature plasma, and the high-temperature plasma is formed. The probability that gas films at the protrusions on the surface of the workpiece are broken down by voltage to generate plasmas is high, and the concentration of the generated high-temperature plasmas is higher than that of the pits, so that the material removal rate is higher than that of the pits, the material removal capacity of the protrusions and the pits is balanced, the microcosmic unevenness is improved, and the polishing effect is improved. The method is mainly used for polishing the surface of the metal material component.

Description

Technical Field

[0001] This invention relates to the field of surface finishing of metal material components. Background Technology

[0002] Polishing metal parts is a crucial process in the industrial field. Its purpose is to obtain a smooth surface to meet the required performance characteristics of the parts.

[0003] Conventional metal parts polishing methods can be mainly divided into mechanical polishing, electrolytic polishing, and chemical polishing. Among them, mechanical polishing has the problems of dust pollution and poor applicability to complex shaped components; electrolytic polishing has the problems of requiring preliminary degreasing and cleaning processes, the working fluid containing strong acids and alkalis, and high waste liquid treatment costs; chemical polishing is difficult to obtain excellent surface quality, and the pollution is even more serious than that of electrolytic polishing.

[0004] Electrolyte plasma polishing is a novel polishing process that uses a specific neutral electrolyte as the anode to conduct electricity, causing a gas vapor film to instantly form on the surface. This film is then broken down by high voltage, generating high-temperature plasma. The gas film is thinner at protrusions and thicker at valleys, making it easier for material in protruding areas to be ejected into plasma under high voltage. This plasma process allows for the preferential removal of material from protruding areas, resulting in a smooth workpiece surface.

[0005] Conventional electrolyte plasma polishing often uses a constant voltage power supply for polishing workpieces. Sun Qiang et al. from Xi'an University of Technology (authorization announcement number: CN 101173361 B) proposed a non-equilibrium liquid composite pulse plasma polishing method. By using a forward pulse voltage or a composite pulse voltage of forward and reverse pulses, the polishing efficiency can be improved and a better surface roughness can be obtained. However, this process is still only suitable for polishing low-roughness components.

[0006] However, existing electrolyte plasma polishing methods only show excellent applicability when the initial surface roughness (≤Ra=1μm) is low.

[0007] For surfaces with high roughness, such as those produced by electrical discharge machining and additive manufacturing, the polishing effect is limited because the gas film will follow the surface contour. Furthermore, the low polishing uniformity for irregularly shaped workpieces like gears is a major reason restricting their further application. Therefore, these problems urgently need to be addressed. Summary of the Invention

[0008] The purpose of this invention is to solve the problems that current electrolyte plasma polishing processes have limited polishing effects on components with high surface roughness and poor polishing uniformity for irregularly shaped structures. This invention provides three electrolytic plasma polishing methods based on pulsed high voltage assistance.

[0009] The first method is an electrolytic plasma polishing method assisted by pulsed high voltage, which includes:

[0010] Step 1: Heat the electrolyte in the working chamber to the preset temperature, and connect the tool electrode as the cathode and the workpiece as the anode to the negative and positive terminals of the pulse high voltage auxiliary power supply, respectively.

[0011] Step 2: Turn on the pulse high voltage auxiliary power supply so that it outputs a voltage waveform with pulse high voltage assistance; wherein, the voltage waveform consists of a base voltage as the low voltage and a pulse high voltage, the base voltage range is 150V to 350V, and the pulse high voltage range is 350V to 700V;

[0012] Step 3: Simultaneously immerse the tool electrode (cathode) and the workpiece (anode) in the electrolyte;

[0013] As the base voltage and pulsed high voltage are applied to the tool electrode and the workpiece, a large amount of Joule heat is instantly generated at the interface between the workpiece and the electrolyte during the process of immersing the tool electrode and the workpiece in the electrolyte, causing the electrolyte to boil and produce a vaporization phenomenon. At the same time, the electrolysis reaction also occurs simultaneously, and gas is also generated on the surface of the workpiece. The Joule heat and the gas generated by the electrolysis reaction form a gas film on the surface of the workpiece. The gas film is broken down by the applied base voltage and pulsed high voltage to generate high-temperature plasma. The high-temperature plasma removes material from the surface of the workpiece, achieving polishing.

[0014] In the process of pulsed high-pressure assisted polishing, energy input is used to form a thicker gas film on the workpiece surface. The high-temperature plasma is more likely to be generated on the protrusions of the workpiece surface than on the depressions, which promotes the preferential removal of material from the protrusions and improves the micro-unevenness of the workpiece surface.

[0015] The thickness of the thicker gas film ranges from 150 μm to 1000 μm;

[0016] Step 4: According to the polishing requirements, after the material removal time reaches the preset time, turn off the pulse high-voltage auxiliary power supply to remove the workpiece from the electrolyte and complete the polishing.

[0017] The second method is based on pulsed high-voltage assisted electrolytic plasma polishing, which includes:

[0018] Step 1: Prepare the electrolyte and heat it to the preset temperature;

[0019] The nozzle and the workpiece serve as the cathode and anode, respectively, and are connected to the negative and positive terminals of the pulsed high-voltage auxiliary power supply, respectively. The distance between the nozzle and the workpiece is adjusted to a preset distance. The nozzle also serves as a tool electrode.

[0020] Step 2: Turn on the pulse high voltage auxiliary power supply so that it outputs a voltage waveform with pulse high voltage assistance; wherein, the voltage waveform consists of a base voltage as the low voltage and a pulse high voltage, the base voltage range is 150V to 350V, and the pulse high voltage range is 350V to 700V.

[0021] Step 3: Control the nozzle, which acts as the tool electrode, to spray electrolyte onto the workpiece. Due to the base voltage and pulsed high voltage applied to the tool electrode and the workpiece, the two become conductive. A large amount of Joule heat is instantly generated at the interface between the workpiece and the electrolyte, causing the electrolyte to boil and vaporize. At the same time, the electrolysis reaction also occurs, generating gas on the workpiece surface. The Joule heat and the gas generated by the electrolysis reaction form a gas film on the workpiece surface. The gas film is broken down by the applied base voltage and pulsed high voltage to generate high-temperature plasma. The high-temperature plasma removes material from the workpiece surface, achieving polishing.

[0022] In the process of pulsed high-pressure assisted polishing, energy input is used to form a thicker gas film on the workpiece surface. The high-temperature plasma is more likely to be generated on the protrusions of the workpiece surface than on the depressions, which promotes the preferential removal of material from the protrusions and improves the micro-unevenness of the workpiece surface.

[0023] The thickness of the thicker gas film ranges from 150 μm to 1000 μm;

[0024] Step 4: According to the polishing requirements, after the material removal time reaches the preset time, turn off the pulse high-voltage auxiliary power supply and control the nozzle to stop spraying electrolyte to complete the polishing.

[0025] The third method is based on pulsed high-voltage assisted electrolytic plasma polishing, which includes:

[0026] Step 1: Heat the electrolyte in the working chamber to the preset temperature, and connect the working chamber, which serves as the cathode, and the workpiece, which serves as the anode, to the negative and positive terminals of the pulse high-voltage auxiliary power supply, respectively; the working chamber also serves as the tool electrode.

[0027] Step 2: Turn on the pulse high voltage auxiliary power supply so that it outputs a voltage waveform with pulse high voltage assistance; wherein, the voltage waveform consists of a base voltage as the low voltage and a pulse high voltage, the base voltage range is 150V to 350V, and the pulse high voltage range is 350V to 700V;

[0028] Step 3: Immerse the workpiece, which will serve as the anode, into the electrolyte;

[0029] As the base voltage and pulsed high voltage are applied to the tool electrode and the workpiece, a large amount of Joule heat is instantly generated at the interface between the workpiece and the electrolyte during the process of immersing the workpiece in the electrolyte, causing the electrolyte to boil and vaporize. At the same time, the electrolysis reaction also occurs simultaneously, and gas is also generated on the surface of the workpiece. The Joule heat and the gas generated by the electrolysis reaction form a gas film on the surface of the workpiece. The gas film is broken down by the applied base voltage and pulsed high voltage to generate high-temperature plasma. The high-temperature plasma removes material from the surface of the workpiece, achieving polishing.

[0030] In the process of pulsed high-pressure assisted polishing, energy input is used to form a thicker gas film on the workpiece surface. The high-temperature plasma is more likely to be generated on the protrusions of the workpiece surface than on the depressions, which promotes the preferential removal of material from the protrusions and improves the micro-unevenness of the workpiece surface.

[0031] The thickness of the thicker gas film ranges from 150 μm to 1000 μm;

[0032] Step 4: According to the polishing requirements, after the material removal time reaches the preset time, turn off the pulse high-voltage auxiliary power supply to remove the workpiece from the electrolyte and complete the polishing.

[0033] Preferably, in the above three methods, the duty cycle of the pulse voltage output by the pulse high voltage auxiliary power supply is 10% to 90%, and the pulse width is 50μs to 10s.

[0034] Preferably, in the above three methods, the preset temperature range of the solution is 65℃ to 95℃.

[0035] Preferably, in the above three methods, the base voltage is 300V, the pulse high voltage is 500V, the pulse voltage duty cycle is 50%, the pulse width is 2 seconds, and the preset temperature is 80℃.

[0036] Preferably, in the first and second methods, the tool electrode and the workpiece are moved by a motion platform.

[0037] Preferably, in the third method, the workpiece is moved by a motion platform.

[0038] The beneficial effects of this invention are:

[0039] The pulsed high-voltage assisted electrolytic plasma polishing method proposed in this invention supplements a conventional constant-voltage power supply with periodic pulsed high voltage. This pulsed high-voltage assistance increases the energy input of the entire system during polishing, thereby forming a thicker gas film on the workpiece surface. This solves the problem in conventional constant-voltage source polishing where a thin gas film, distributed conformally on a high-roughness surface, leads to a lower material removal rate difference between microscopic protrusions and depressions on the component surface, thus limiting the polishing effect. Although increasing the polishing voltage can also increase the gas film thickness when using a constant-voltage source, the resulting decrease in polishing efficiency and stability remains difficult to resolve.

[0040] Furthermore, the auxiliary pulsed high voltage based on the constant voltage source in this invention can improve the uniformity of plasma discharge in irregularly shaped structural components, thereby achieving high surface quality and high conformal polishing of irregularly shaped structures with high roughness surface contours. Attached Figure Description

[0041] Figure 1 This is a schematic diagram of an electrolytic plasma polishing device;

[0042] Figure 2 A schematic diagram of the voltage waveform output by the high-voltage auxiliary power supply with pulse high-voltage assistance;

[0043] Figure 3 This is a surface morphology diagram of the EDM part before polishing in Example 1;

[0044] Figure 4 This is a surface morphology diagram of the EDM part in Example 1 after polishing. Detailed Implementation

[0045] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0046] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0047] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the scope of the invention.

[0048] Specific Implementation Method 1: Combination Figure 1 and Figure 2 This embodiment describes a pulsed high-voltage assisted electrolytic plasma polishing method, which includes:

[0049] Step 1: Heat the electrolyte in the working chamber to the preset temperature, and connect the tool electrode as the cathode and the workpiece as the anode to the negative and positive terminals of the pulse high voltage auxiliary power supply, respectively.

[0050] Step 2: Turn on the pulse high voltage auxiliary power supply so that it outputs a voltage waveform with pulse high voltage assistance; the voltage waveform consists of a base voltage as the low voltage and a pulse high voltage. The base voltage ranges from 150V to 350V, and the pulse high voltage ranges from 350V to 700V; the minimum voltage difference between the base voltage and the pulse high voltage is 100V.

[0051] Step 3: Simultaneously immerse the tool electrode (cathode) and the workpiece (anode) in the electrolyte;

[0052] As the base voltage and pulsed high voltage are applied to the tool electrode and the workpiece, a large amount of Joule heat is instantly generated at the interface between the workpiece and the electrolyte during the process of immersing the tool electrode and the workpiece in the electrolyte, causing the electrolyte to boil and produce a vaporization phenomenon. At the same time, the electrolysis reaction also occurs simultaneously, and gas is also generated on the surface of the workpiece. The Joule heat and the gas generated by the electrolysis reaction form a gas film on the surface of the workpiece. The gas film is broken down by the applied base voltage and pulsed high voltage to generate high-temperature plasma. The high-temperature plasma removes material from the surface of the workpiece, achieving polishing.

[0053] In the process of pulsed high-pressure assisted polishing, energy input is used to form a thicker gas film on the workpiece surface. The high-temperature plasma is more likely to be generated on the protrusions of the workpiece surface than on the depressions, which promotes the preferential removal of material from the protrusions and improves the micro-unevenness of the workpiece surface.

[0054] The thickness of the thicker gas film ranges from 150 μm to 1000 μm;

[0055] Step 4: According to the polishing requirements, after the material removal time reaches the preset time, turn off the pulse high-voltage auxiliary power supply to remove the workpiece from the electrolyte and complete the polishing.

[0056] Specifically, the tool electrode and the workpiece can be moved by a motion platform. In this embodiment, the gas generated by Joule heating and electrolysis will form a high-resistance gas film on the surface of the workpiece. The high-resistance gas film will be broken down by the applied high voltage to generate high-temperature plasma. The probability of the gas film at the protrusions on the workpiece surface being broken down by voltage to generate plasma is higher. The concentration of the generated high-temperature plasma is higher than that at the depressions. Therefore, it has a higher material removal rate than the depressions. It balances the material removal capacity of the protrusions and depressions, improves the micro-unevenness, and makes the workpiece surface smooth.

[0057] Pulsed high-pressure assistance can increase the energy input of the entire system during the polishing process, thereby forming a thicker gas film on the workpiece surface. This can solve the problem that the thin gas film distributed on the high-roughness surface during conventional polishing leads to a low difference in material removal rate between microscopic protrusions and depressions on the component surface, thus limiting the polishing effect.

[0058] Because the base voltage is also greater than the voltage required to generate plasma, polishing continues throughout the entire processing.

[0059] Furthermore, pulsed high voltage assistance can improve the uniformity of plasma discharge in irregularly shaped structural components, thereby achieving high surface quality and high conformal polishing of irregularly shaped structures with high roughness.

[0060] Specifically, the motion platform drives the tool electrode and the workpiece to move. In addition, pulsed high voltage assistance can improve the uniformity of plasma discharge in irregularly shaped structural components, thereby achieving high surface quality and high conformal polishing of irregularly shaped structures with high roughness.

[0061] Furthermore, the duty cycle of the pulse voltage output by the pulse high-voltage auxiliary power supply is 10% to 90%, the pulse width is 50 μs to 10 s, and the preset temperature range of the electrolyte is 65°C to 95°C. Parameters within this range are suitable for achieving efficient smoothing of rough surfaces.

[0062] Furthermore, the optimal base voltage is 300V, the optimal pulse high voltage is 500V, the optimal pulse voltage duty cycle is 50%, the optimal pulse width is 2 seconds, and the preset temperature is 80℃.

[0063] Specific Implementation Method Two: Combination Figure 2 As shown in this embodiment, the electrolytic plasma polishing method based on pulsed high voltage assistance includes:

[0064] Step 1: Prepare the electrolyte and heat it to the preset temperature;

[0065] The nozzle and the workpiece serve as the cathode and anode, respectively, and are connected to the negative and positive terminals of the pulsed high-voltage auxiliary power supply, respectively. The distance between the nozzle and the workpiece is adjusted to a preset distance. The nozzle also serves as a tool electrode.

[0066] Step 2: Turn on the pulse high voltage auxiliary power supply so that it outputs a voltage waveform with pulse high voltage assistance; the voltage waveform consists of a base voltage as the low voltage and a pulse high voltage. The base voltage ranges from 150V to 350V, and the pulse high voltage ranges from 350V to 700V; the minimum voltage difference between the base voltage and the pulse high voltage is 100V.

[0067] Step 3: Control the nozzle, which acts as the tool electrode, to spray electrolyte onto the workpiece. Due to the base voltage and pulsed high voltage applied to the tool electrode and the workpiece, the two become conductive. A large amount of Joule heat is instantly generated at the interface between the workpiece and the electrolyte, causing the electrolyte to boil and vaporize. At the same time, the electrolysis reaction also occurs, generating gas on the workpiece surface. The Joule heat and the gas generated by the electrolysis reaction form a gas film on the workpiece surface. The gas film is broken down by the applied base voltage and pulsed high voltage to generate high-temperature plasma. The high-temperature plasma removes material from the workpiece surface, achieving polishing.

[0068] In the process of pulsed high-pressure assisted polishing, energy input is used to form a thicker gas film on the workpiece surface. The high-temperature plasma is more likely to be generated on the protrusions of the workpiece surface than on the depressions, which promotes the preferential removal of material from the protrusions and improves the micro-unevenness of the workpiece surface.

[0069] The thickness of the thicker gas film ranges from 150 μm to 1000 μm;

[0070] Step 4: According to the polishing requirements, after the material removal time reaches the preset time, turn off the pulse high-voltage auxiliary power supply and control the nozzle to stop spraying electrolyte to complete the polishing.

[0071] In this embodiment, the gas generated by Joule heating and electrolysis forms a high-resistance gas film on the surface of the workpiece. The high-resistance gas film is broken down by the applied high voltage to generate high-temperature plasma. The probability of the gas film at the protrusions on the workpiece surface being broken down by voltage to generate plasma is higher, and the concentration of the generated high-temperature plasma is higher than that at the depressions. Therefore, it has a higher material removal rate than the depressions, balances the material removal capacity of the protrusions and depressions, improves the micro-unevenness, and makes the workpiece surface smooth.

[0072] Pulsed high-pressure assistance can increase the energy input of the entire system during the polishing process, thereby forming a thicker gas film on the workpiece surface. This can solve the problem that the thin gas film distributed on the high-roughness surface during conventional polishing leads to a low difference in material removal rate between microscopic protrusions and depressions on the component surface, thus limiting the polishing effect.

[0073] Because the base voltage is also greater than the voltage required to generate plasma, polishing continues throughout the entire processing.

[0074] Furthermore, pulsed high voltage assistance can improve the uniformity of plasma discharge in irregularly shaped structural components, thereby achieving high surface quality and high conformal polishing of irregularly shaped structures with high roughness.

[0075] Specifically, the motion platform drives the tool electrode and the workpiece to move. In addition, pulsed high voltage assistance can improve the uniformity of plasma discharge in irregularly shaped structural components, thereby achieving high surface quality and high conformal polishing of irregularly shaped structures with high roughness.

[0076] Furthermore, the duty cycle of the pulse voltage output by the pulse high-voltage auxiliary power supply is 10% to 90%, the pulse width is 50 μs to 10 s, and the preset temperature range of the electrolyte is 65°C to 95°C. Parameters within this range are suitable for achieving efficient smoothing of rough surfaces.

[0077] Furthermore, the optimal base voltage is 300V, the optimal pulse high voltage is 500V, the optimal pulse voltage duty cycle is 50%, the optimal pulse width is 2 seconds, and the preset temperature is 80℃.

[0078] Detailed implementation method three, see also Figure 2 The pulsed high-voltage assisted electrolytic plasma polishing method described in this embodiment includes:

[0079] Step 1: Heat the electrolyte in the working chamber to the preset temperature, and connect the working chamber, which serves as the cathode, and the workpiece, which serves as the anode, to the negative and positive terminals of the pulse high-voltage auxiliary power supply, respectively; the working chamber also serves as the tool electrode.

[0080] Step 2: Turn on the pulse high voltage auxiliary power supply so that it outputs a voltage waveform with pulse high voltage assistance; wherein, the voltage waveform consists of a base voltage as the low voltage and a pulse high voltage, the base voltage range is 150V to 350V, and the pulse high voltage range is 350V to 700V;

[0081] Step 3: Immerse the workpiece, which will serve as the anode, into the electrolyte;

[0082] As the base voltage and pulsed high voltage are applied to the tool electrode and the workpiece, a large amount of Joule heat is instantly generated at the interface between the workpiece and the electrolyte during the process of immersing the workpiece in the electrolyte, causing the electrolyte to boil and vaporize. At the same time, the electrolysis reaction also occurs simultaneously, and gas is also generated on the surface of the workpiece. The Joule heat and the gas generated by the electrolysis reaction form a gas film on the surface of the workpiece. The gas film is broken down by the applied base voltage and pulsed high voltage to generate high-temperature plasma. The high-temperature plasma removes material from the surface of the workpiece, achieving polishing.

[0083] In the process of pulsed high-pressure assisted polishing, energy input is used to form a thicker gas film on the workpiece surface. The high-temperature plasma is more likely to be generated on the protrusions of the workpiece surface than on the depressions, which promotes the preferential removal of material from the protrusions and improves the micro-unevenness of the workpiece surface.

[0084] The thickness of the thicker gas film ranges from 150 μm to 1000 μm;

[0085] Step 4: According to the polishing requirements, after the material removal time reaches the preset time, turn off the pulse high-voltage auxiliary power supply to remove the workpiece from the electrolyte and complete the polishing.

[0086] In this embodiment, the gas generated by Joule heating and electrolysis forms a high-resistance gas film on the surface of the workpiece. The high-resistance gas film is broken down by the applied high voltage to generate high-temperature plasma. The probability of the gas film at the protrusions on the workpiece surface being broken down by voltage to generate plasma is higher, and the concentration of the generated high-temperature plasma is higher than that at the depressions. Therefore, it has a higher material removal rate than the depressions, balances the material removal capacity of the protrusions and depressions, improves the micro-unevenness, and makes the workpiece surface smooth.

[0087] Pulsed high-pressure assistance can increase the energy input of the entire system during the polishing process, thereby forming a thicker gas film on the workpiece surface. This can solve the problem that the thin gas film distributed on the high-roughness surface during conventional polishing leads to a low difference in material removal rate between microscopic protrusions and depressions on the component surface, thus limiting the polishing effect.

[0088] Because the base voltage is also greater than the voltage required to generate plasma, polishing continues throughout the entire processing.

[0089] Furthermore, pulsed high voltage assistance can improve the uniformity of plasma discharge in irregularly shaped structural components, thereby achieving high surface quality and high conformal polishing of irregularly shaped structures with high roughness.

[0090] Specifically, the workpiece is moved by a motion platform. In addition, pulsed high voltage assistance can improve the uniformity of plasma discharge in irregularly shaped structural components, thereby achieving high surface quality and high conformal polishing of irregularly shaped structures with high roughness.

[0091] Furthermore, the duty cycle of the pulse voltage output by the pulse high-voltage auxiliary power supply is 10% to 90%, the pulse width is 50 μs to 10 s, and the preset temperature range of the electrolyte is 65°C to 95°C. Parameters within this range are suitable for achieving efficient smoothing of rough surfaces.

[0092] Furthermore, the optimal base voltage is 300V, the optimal pulse high voltage is 500V, the optimal pulse voltage duty cycle is 50%, the optimal pulse width is 2 seconds, and the preset temperature is 80℃.

[0093] Verification experiment:

[0094] Example 1: The polishing object is an irregularly shaped workpiece made of 316L stainless steel after wire EDM, with an initial roughness Ra=2.0.

[0095] S1. Prepare a polishing solution with a 3% (w / w) ammonium sulfate concentration.

[0096] S2. Clamp the workpiece to be polished and the tool cathode on the lifting device and adjust the distance between them to 10 cm.

[0097] S3. Activate the heating device to heat the polishing liquid in the cavity and stir appropriately to ensure uniform heating. The temperature is 80°C, which is suitable for electrolytic plasma polishing. At this temperature, the polishing liquid requires less heat to reach boiling. During the polishing process, the surface of the workpiece to be polished generates relatively small Joule heat to form a surface gas envelope layer, which is beneficial to the polishing process.

[0098] S4. Set the base voltage of the pulse high-voltage auxiliary power supply to 300V, the amplitude of the auxiliary pulse high-voltage power supply to 500V, the pulse width to 0.5s, and the duty cycle to 50%;

[0099] S5. Turn on the power, immerse the workpiece and tool cathode to be polished into the polishing liquid in the tank through the lifting device, start the timer, turn off the power after 20 minutes of polishing time, and lift the workpiece and tool cathode.

[0100] Figure 3 and Figure 4 The images show the workpiece before and after polishing. The roughness inside the groove decreased from the initial Ra=2.0 to Ra=0.35, and the roughness on the upper surface decreased from Ra=1.4 to Ra=0.2. This demonstrates the advantages of this method in polishing irregularly shaped structural components with high roughness surfaces (>Ra=1μm).

[0101] While the invention has been described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the invention. Therefore, it should be understood that many modifications can be made to the exemplary embodiments, and other arrangements can be designed without departing from the spirit and scope of the invention as defined by the appended claims. It should be understood that different dependent claims and features described herein can be combined in ways different from those described in the original claims. It is also understood that features described in conjunction with individual embodiments can be used in other described embodiments.

Claims

1. A pulsed high-voltage assisted electrolytic plasma polishing method, characterized in that, The method includes: Step 1: Heat the electrolyte in the working chamber to the preset temperature, and connect the tool electrode as the cathode and the workpiece as the anode to the negative and positive terminals of the pulse high voltage auxiliary power supply, respectively. Step 2: Turn on the pulse high voltage auxiliary power supply so that it outputs a voltage waveform with pulse high voltage assistance; wherein, the voltage waveform consists of a base voltage as the low voltage and a pulse high voltage, the base voltage range is 150V to 350V, and the pulse high voltage range is 350V to 700V; Step 3: Simultaneously immerse the tool electrode (cathode) and the workpiece (anode) in the electrolyte; As the base voltage and pulsed high voltage are applied to the tool electrode and the workpiece, a large amount of Joule heat is instantly generated at the interface between the workpiece and the electrolyte during the process of immersing the tool electrode and the workpiece in the electrolyte, causing the electrolyte to boil and produce a vaporization phenomenon. At the same time, the electrolysis reaction also occurs simultaneously, and gas is also generated on the surface of the workpiece. The Joule heat and the gas generated by the electrolysis reaction form a gas film on the surface of the workpiece. The gas film is broken down by the applied base voltage and pulsed high voltage to generate high-temperature plasma. The high-temperature plasma removes material from the surface of the workpiece, achieving polishing. In the process of pulsed high-pressure assisted polishing, energy input is used to form a thicker gas film on the workpiece surface. The high-temperature plasma is more likely to be generated on the protrusions of the workpiece surface than on the depressions, which promotes the preferential removal of material from the protrusions and improves the micro-unevenness of the workpiece surface. The thickness of the thicker gas film ranges from 150 μm to 1000 μm; Step 4: According to the polishing requirements, after the material removal time reaches the preset time, turn off the pulse high-voltage auxiliary power supply to remove the workpiece from the electrolyte and complete the polishing.

2. A pulsed high-voltage assisted electrolytic plasma polishing method, characterized in that, The method includes: Step 1: Prepare the electrolyte and heat it to the preset temperature; The nozzle and the workpiece serve as the cathode and anode, respectively, and are connected to the negative and positive terminals of the pulsed high-voltage auxiliary power supply, respectively. The distance between the nozzle and the workpiece is adjusted to a preset distance. The nozzle also serves as a tool electrode. Step 2: Turn on the pulse high voltage auxiliary power supply so that it outputs a voltage waveform with pulse high voltage assistance; wherein, the voltage waveform consists of a base voltage as the low voltage and a pulse high voltage, the base voltage range is 150V to 350V, and the pulse high voltage range is 350V to 700V. Step 3: Control the nozzle, which acts as the tool electrode, to spray electrolyte onto the workpiece. Due to the base voltage and pulsed high voltage applied to the tool electrode and the workpiece, the two become conductive. A large amount of Joule heat is instantly generated at the interface between the workpiece and the electrolyte, causing the electrolyte to boil and vaporize. At the same time, the electrolysis reaction also occurs, generating gas on the workpiece surface. The Joule heat and the gas generated by the electrolysis reaction form a gas film on the workpiece surface. The gas film is broken down by the applied base voltage and pulsed high voltage to generate high-temperature plasma. The high-temperature plasma removes material from the workpiece surface, achieving polishing. In the process of pulsed high-pressure assisted polishing, energy input is used to form a thicker gas film on the workpiece surface. The high-temperature plasma is more likely to be generated on the protrusions of the workpiece surface than on the depressions, which promotes the preferential removal of material from the protrusions and improves the micro-unevenness of the workpiece surface. The thickness of the thicker gas film ranges from 150 μm to 1000 μm; Step 4: According to the polishing requirements, after the material removal time reaches the preset time, turn off the pulse high-voltage auxiliary power supply and control the nozzle to stop spraying electrolyte to complete the polishing.

3. A pulsed high-voltage assisted electrolytic plasma polishing method, characterized in that, The method includes: Step 1: Heat the electrolyte in the working chamber to the preset temperature, and connect the working chamber, which serves as the cathode, and the workpiece, which serves as the anode, to the negative and positive terminals of the pulse high-voltage auxiliary power supply, respectively; the working chamber also serves as the tool electrode. Step 2: Turn on the pulse high voltage auxiliary power supply so that it outputs a voltage waveform with pulse high voltage assistance; wherein, the voltage waveform consists of a base voltage as the low voltage and a pulse high voltage, the base voltage range is 150V to 350V, and the pulse high voltage range is 350V to 700V; Step 3: Immerse the workpiece, which will serve as the anode, into the electrolyte; As the base voltage and pulsed high voltage are applied to the tool electrode and the workpiece, a large amount of Joule heat is instantly generated at the interface between the workpiece and the electrolyte during the process of immersing the workpiece in the electrolyte, causing the electrolyte to boil and vaporize. At the same time, the electrolysis reaction also occurs simultaneously, and gas is also generated on the surface of the workpiece. The Joule heat and the gas generated by the electrolysis reaction form a gas film on the surface of the workpiece. The gas film is broken down by the applied base voltage and pulsed high voltage to generate high-temperature plasma. The high-temperature plasma removes material from the surface of the workpiece, achieving polishing. In the process of pulsed high-pressure assisted polishing, energy input is used to form a thicker gas film on the workpiece surface. The high-temperature plasma is more likely to be generated on the protrusions of the workpiece surface than on the depressions, which promotes the preferential removal of material from the protrusions and improves the micro-unevenness of the workpiece surface. The thickness of the thicker gas film ranges from 150 μm to 1000 μm; Step 4: According to the polishing requirements, after the material removal time reaches the preset time, turn off the pulse high-voltage auxiliary power supply to remove the workpiece from the electrolyte and complete the polishing.

4. The method for electrolytic plasma polishing based on pulsed high voltage assisted according to claim 1, 2, or 3, characterized in that, The duty cycle of the pulse voltage output by the pulse high voltage auxiliary power supply is 10% to 90%, and the pulse width is 50μs to 10s.

5. The method for electrolytic plasma polishing based on pulsed high voltage assisted polishing according to claim 1, 2, or 3, characterized in that, The preset temperature range for the electrolyte is 65℃ to 95℃.

6. The method for electrolytic plasma polishing based on pulsed high voltage assisted polishing according to claim 1, 2, or 3, characterized in that, The base voltage is 300V, and the pulse high voltage is 500V.

7. The method for electrolytic plasma polishing based on pulsed high voltage assisted polishing according to claim 1, 2, or 3, characterized in that, The duty cycle of the pulse voltage is 50%, and the pulse width is 2 seconds.

8. The method for electrolytic plasma polishing based on pulsed high voltage assisted polishing according to claim 1, 2, or 3, characterized in that, The preset temperature is 80℃.

9. The method for electrolytic plasma polishing based on pulsed high voltage assisted according to claim 1 or 2, characterized in that, The motion platform drives the tool electrode and the workpiece to move.

10. The method for electrolytic plasma polishing based on pulsed high voltage assisted according to claim 3, characterized in that, The workpiece is moved by a motion platform.

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