METHOD AND APPARATUS FOR GAS-DRIVEN JET POLISHING AND APPLICATION THEREOF

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

Pursuant to 35 U.S.C. § 119 and the Paris Convention, this application claims the benefit of Chinese Patent Application No. 202411629880.9 filed Nov. 14, 2024, the contents of which are incorporated herein by reference.

BACKGROUND

Technical Field

The present application relates to the field of polishing technology, and in particular relates to a polishing method and apparatus for gas-driven jets and an application thereof.

Description of Related Art

Optical components with complex surfaces, which include freeform optical surfaces and structured optical surfaces, significantly reduce the complexity of optical systems owing to their arbitrary geometries and irregular surface structures. This enables the concurrent achievement of lightweight and high-performance characteristics in optical systems. In recent years, such complex optical components have found wide applications in fields including aerospace, lasers, communications, biomedicine, energy, and automotive.

Currently, the machining of complex optical surfaces is primarily accomplished via single-point diamond ultra-precision turning. This technique can achieve nanometer-level surface roughness and high form accuracy. However, tool marks remaining on the optical component surface after machining induce issues such as small-angle scattering within the optical system, thereby degrading the component's performance.

To address this, researchers worldwide have conducted extensive and fruitful investigations, proposing numerous polishing methods aimed at removing tool marks from complex optical surfaces. These methods include magnetorheological polishing, bonnet (or airbag) polishing, ion beam sputtering planarization, ultrasonic-assisted abrasive polishing, local vibration-assisted magnetic abrasive polishing, and magnetic field-assisted polishing. Although these techniques effectively enhance the surface quality of optical components, they all rely on the direct contact of a rigid polishing medium with the workpiece surface. This inherent characteristic leads to insufficient process flexibility and poses a critical, unresolved challenge: the difficulty in controlling the uniformity of contact between the polishing medium and the complex surface. Consequently, maintaining stable form accuracy and uniform polished surface quality remains problematic. Moreover, simultaneously achieving sub-nanometer surface roughness, high polishing efficiency, and minimal subsurface damage is exceedingly difficult. Consequently, reports on the practical application of these technologies in the realm of ultra-precision polishing for complex optical surfaces are scarce.

SUMMARY

It is one of objectives of the present application to provide a method and an apparatus for gas-driven jet polishing, and an application thereof, aiming to solve, to some extent, the problems of existing polishing methods in achieving sub-nanometer-level surface roughness, high polishing efficiency, and minimal sub-surface damage.

To achieve the above-mentioned objective, the following technical solutions are adopted in the present application:

A first aspect of the present application provides a method for gas-driven jet polishing, comprising the following steps:

• • obtaining a polishing slurry comprising a nano-abrasive, a dispersion aid, and a solvent;
  • immersing at least a surface to be polished of a workpiece in the polishing slurry, and polishing the surface to be polished of the workpiece by forming a gas jet in the polishing slurry using a gas pressure.

In some possible embodiments, the nano-abrasive comprises at least one of silicon dioxide and cerium dioxide.

In some possible embodiments, an average particle size of the nano-abrasive is 1 nm to 1000 nm.

In some possible embodiments, a mass percentage of the nano-abrasive in the polishing slurry is 1% to 20%.

In some possible embodiments, the dispersion aid comprises at least one of a dispersant and a suspending agent.

In some possible embodiments, the solvent comprises water.

In some possible embodiments, the dispersant comprises at least one selected from the group consisting of a sodium polyacrylate, a polyacrylamide, a tripolyphosphate salt, and sodium dodecylbenzenesulfonate.

In some possible embodiments, the suspending agent comprises at least one selected from the group consisting of a carboxymethyl cellulose and a xanthan gum.

In some possible embodiments, in the polishing slurry, a mass percentage of the dispersant is 0.1% to 5%.

In some possible embodiments, in the polishing slurry, a mass percentage of the suspending agent is 0.1% to 5%.

In some possible embodiments, the step of polishing the surface to be polished of the workpiece comprises: immersing the workpiece and a gas flow nozzle in the polishing slurry, ejecting gas through the gas flow nozzle into the polishing slurry to form the gas jet, in which, an impact direction of the gas jet is directed toward the surface to be polished of the workpiece for polishing.

In some possible embodiments, a distance between the surface to be polished of the workpiece and the gas flow nozzle is greater than 0 and less than or equal to 15 mm.

In some possible embodiments, an angle between the impact direction of the gas jet and the surface to be polished of the workpiece is greater than 0 and less than or equal to 90°.

In some possible embodiments, a motion trajectory of the gas flow nozzle relative to the workpiece comprises a zigzag path, a spiral path, or an irregular path.

In some possible embodiments, a gas pressure at an outlet of the gas flow nozzle is greater than 0 and less than or equal to 4 bar.

In some possible embodiments, an outlet of the gas flow nozzle is configured in a pattern comprising a single orifice, multiple orifices, or a linear slit.

A second aspect of the present application provides an apparatus for gas-driven jet polishing, comprising:

• • a polishing container, configured to hold a polishing slurry and a workpiece which is to be polished;
  • a gas flow nozzle, configured to be immersed in the polishing slurry in the polishing container during operation; and
  • a controller, configured to control a gas flow at an outlet of the gas flow nozzle to form a gas jet toward the workpiece in the polishing slurry.

In some possible embodiments, the outlet of the gas flow nozzle is oriented towards the workpiece.

In some possible embodiments, the polishing container further comprises a worktable, and the workpiece is disposed on the worktable.

In some possible embodiments, the controller comprises a gas flow controller and a motion controller, the gas flow controller is configured to control the gas flow from the outlet of the gas flow nozzle, and the motion controller is configured to control a motion trajectory of the gas flow nozzle.

In some possible embodiments, a distance between the gas flow nozzle and a surface to be polished of the workpiece is greater than 0 and less than or equal to 15 mm.

In some possible embodiments, an angle between the gas flow nozzle and a surface to be polished of the workpiece is greater than 0 and less than or equal to 90°.

In some possible embodiments, an outlet of the gas flow nozzle is configured in a pattern comprising a single orifice, multiple orifices, or a linear slit.

In some possible embodiments, the gas flow controller and the gas flow nozzle are connected via a gas tube.

In some possible embodiments, the gas flow controller controls gas to eject from the gas flow nozzle at a constant pressure greater than 0 and less than or equal to 4 bar.

In some possible embodiments, the motion controller regulates the motion trajectory of the gas flow nozzle relative to the workpiece as a zigzag path, a spiral path, or an irregular path.

In some possible embodiments, the distance between the gas flow nozzle and the surface to be polished of the workpiece is 5 mm to 15 mm.

In some possible embodiments, the angle between the gas flow nozzle and the surface to be polished of the workpiece is 60° to 90°.

A third aspect of the present application provides a method for polishing an optically complex curved surface part. The method comprises: polishing the optically complex curved surface part using the method for gas-driven jet polishing as described in the above and/or the apparatus for gas-driven jet polishing as described in the above.

In the method for gas-driven jet polishing provided in the first aspect of the present application, on the one hand, the nano-abrasive contained in the polishing slurry not only possess high chemical activity, enabling a chemical reaction with the surface of the workpiece during polishing, but also has high mechanical strength, thereby exerting mechanical impact on the workpiece during polishing. This dual action of chemical reaction and mechanical impact allows for better atomic-scale polishing of the workpiece. On the other hand, at least the surface to be polished of the workpiece is immersed in the polishing slurry. The workpiece is polished by an immersion-type, gas-driven jet polishing method, which can generate extremely high-velocity gas jets even at low pressure. These high-velocity gas jets, in turn, accelerate the nano-abrasive particles in the slurry, causing them to impact the workpiece surface at high velocity. This process achieves highly efficient material removal and polishing. In addition, the immersion-type, gas-driven jet polishing method operates at low pressure, leading to low energy consumption and reduced process costs. Additionally, the polishing slurry does not require pipeline transportation, reduces wear on the apparatus. It is also less prone to contamination, maintains a stable concentration, and allows for flexible control of the composition and concentration of the polishing slurry, significantly improving process efficiency. The method for gas-driven jet polishing of the present application can remove defects such as scratches, pits, and oxide scale from the surface of the workpiece, making the surface smoother and more uniform, significantly reducing the microscopic unevenness of the surface of the workpiece, making it smoother, and achieving high surface quality of the polished workpiece, realizing sub-nanometer surface roughness, high polishing efficiency, and low sub-surface damage.

The apparatus for gas-driven jet polishing provided by embodiments of the present application comprises a polishing container, which holds a polishing slurry and a workpiece to be polished. The polishing process of the workpiece takes place within the polishing container. The apparatus further comprises a gas flow nozzle, which is immersed in the polishing slurry in the polishing container during operation and can be removed from the polishing container when not in operation. A controller controls the gas flow at the outlet of the gas flow nozzle to form a gas jet in the polishing slurry directed towards the workpiece. This accelerates the polishing effect of the abrasive particles in the polishing slurry on the surface of the workpiece, achieving atomic-scale material removal and sub-nanometer surface roughness. This apparatus for gas-driven jet polishing can efficiently and effectively polish complex free-form surfaces, operates at low pressure, leading to low energy consumption and reduced process costs. Additionally, the polishing slurry does not require pipeline transportation, reduces wear on the apparatus. It is also less prone to contamination, maintains a stable concentration, and allows for flexible control of the composition and concentration of the polishing slurry, significantly improving process efficiency. Furthermore, the apparatus for gas-driven jet polishing of the present application features simple equipment development, eliminates the need for a polishing slurry circulation system and a high-performance pressure pump, avoids valve and nozzle wear, and is low in cost.

The method and the apparatus for gas-driven jet polishing of the above embodiments of the present application can achieve high surface quality on the workpiece, realize sub-nanometer surface roughness, high polishing efficiency, and low sub-surface damage. In addition, the polishing method and the polishing apparatus ensure uniform contact between the polishing medium and the complex surface, maintaining stable shape accuracy and uniform polished surface quality for optically complex curved surfaces, achieving ultra-precision machining and sub-nanometer-level surface roughness for optically complex curved surfaces.

DESCRIPTION OF THE DRAWINGS

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

FIG. 1 is a flowchart illustrating a method for gas-driven jet polishing provided in an embodiment of the present application;

FIG. 2 is a structural schematic diagram of an apparatus for gas-driven jet polishing provided in an embodiment of the present application;

FIG. 3 is diagram showing outlet patterns of gas flow nozzles in the apparatus for gas-driven jet polishing provided in an embodiment of the present application;

FIG. 4 is a physical image of an apparatus for gas-driven jet polishing used Examples 1-14 of the present application;

FIG. 5 is a microscopic morphology diagram of a surface of a monocrystalline silicon workpiece after polishing provided by Example 1 of the present application;

FIG. 6 is a microscopic morphology diagram of a surface of an optical glass workpiece after polishing provided by Example 2 of the present application;

In the figures, the following reference numerals are adopted:

• • 1—Gas flow controller; 2—Motion controller; 3—Gas flow nozzle;
  • 4—Workpiece; 5—Worktable; 6—Polishing slurry; 7—Gas tube; and 8—Polishing container.

DETAILED DESCRIPTION OF THE EMBODIMENTS

To make the technical problems to be solved, technical solutions, and beneficial effects of the present application clearer, the following detailed description is provided with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are intended to illustrate the present application and are not intended to limit the scope of the present application.

In the present application, the term “and/or” describes the relationship between related objects, indicating that three relationships can exist. For example, “A and/or B” may indicate: A alone, both A and B, or B alone. Herein, A and B may be singular or plural. The character “/” generally indicates an “or” relationship between the preceding and following associated objects.

In the present application, “at least one” means one or more, and “a plurality of” means two or more. “At least one of the following” or similar expressions refer to any combination of the listed items, including any combination of singular or plural items. For example, “at least one of a, b, or c” or “at least one of a, b, and c” may mean: a, b, c, a-b (i.e., a and b), a-c, b-c, or a-b-c, wherein a, b, and c may each be single or multiple.

It should be understood that in various embodiments of the present application, the sequence numbers of the foregoing processes do not imply an order of execution. Some or all steps may be performed in parallel or sequentially. The execution order of each process should be determined by its function and internal logic and should not constitute any limitation to the implementation of the embodiments of the present application.

The terminology used in the embodiments of the present application is for the purpose of describing particular embodiments only and is not intended to limit the present application. As used in the embodiments of the present application and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise.

The weights of the relevant components mentioned in the embodiments of the description of the present application may refer not only to the specific amounts of each component but also to the proportional weight relationship among the components. Therefore, any scaling up or down of the component amounts based on the ratios described in the embodiments of the present application is within the scope disclosed in these embodiments. Specifically, the mass referred to in the embodiments of the description of the present application may be in units well-known in the chemical field, such as μg, mg, g, or kg.

The terms “first” and “second” are used for descriptive purposes only and are used to distinguish between objects, such as substances, and are not to be construed as indicating or implying relative importance or implicitly indicating the number of indicated technical features. For example, without departing from the scope of the embodiments of the present application, a first XX may also be referred to as a second XX, and similarly, a second XX may also be referred to as a first XX. Thus, features defined with “first” and “second” may explicitly or implicitly include one or more such features.

A first aspect of embodiments of the present application provides a method for gas-driven jet polishing, as shown in FIG. 1, comprising the following steps:

• • S10, obtaining a polishing slurry comprising a nano-abrasive, a dispersion aid, and a solvent; and
  • S20, immersing at least a surface to be polished of a workpiece in the polishing slurry, and polishing the surface to be polished of the workpiece by forming a gas jet in the polishing slurry using a gas pressure.

In the method for gas-driven jet polishing provided in the first aspect of the present application, on the one hand, the nano-abrasive contained in the polishing slurry not only possess high chemical activity, enabling a chemical reaction with the surface of the workpiece during polishing, but also has high mechanical strength, thereby exerting mechanical impact on the workpiece during polishing. This dual action of chemical reaction and mechanical impact allows for better atomic-scale polishing of the workpiece. On the other hand, at least the surface to be polished of the workpiece is immersed in the polishing slurry. The workpiece is polished by an immersion-type, gas-driven jet polishing method, which can generate extremely high-velocity gas jets even at low pressure. These high-velocity gas jets, in turn, accelerate the nano-abrasive particles in the slurry, causing them to impact the workpiece surface at high velocity. This process achieves highly efficient material removal and polishing. In addition, the immersion-type, gas-driven jet polishing method operates at low pressure, leading to low energy consumption and reduced process costs. Additionally, the polishing slurry does not require pipeline transportation, reduces wear on the apparatus. It is also less prone to contamination, maintains a stable concentration, and allows for flexible control of the composition and concentration of the polishing slurry, significantly improving process efficiency. The method for gas-driven jet polishing of the present application can remove defects such as scratches, pits, and oxide scale from the surface of the workpiece, making the surface smoother and more uniform, significantly reducing the microscopic unevenness of the surface of the workpiece, making it smoother, and achieving high surface quality of the polished workpiece, realizing sub-nanometer surface roughness, high polishing efficiency, and low sub-surface damage.

In step S10:

In some possible embodiments, the nano-abrasive comprises at least one of silicon dioxide and cerium dioxide. In the polishing slurry of the present application, the nano-abrasive mainly uses silicon dioxide and cerium oxide. These two abrasives exhibit strong chemical activity in the polishing slurry. Under the action of water, the unsaturated oxygen on the surface of the polishing abrasive generates silanol and ceriumolyl hydroxyl structures. These chemical structures can react chemically with the workpiece surface, thereby improving the polishing effect. Through the synergistic effect of chemical and mechanical processes, a high-quality surface at the atomic-scale is achieved after polishing. Silicon dioxide particles have high hardness and can uniformly grind the workpiece surface at the micron level, precisely controlling the polishing effect. Cerium oxide nano-abrasives have strong cutting force, enabling the polishing task to be completed in a short time, improving production efficiency. Furthermore, silicon dioxide and cerium oxide have certain chemical activity and can react chemically with the surface of the object being polished during the polishing process, thereby accelerating the polishing process. This chemical reaction helps remove surface stains and impurities, improving the polishing effect.

In some embodiments, the nano-abrasive additionally comprises silicon dioxide and cerium dioxide. Through the combined action of multiple nano-abrasives.

In some possible embodiments, an average particle size of the nano-abrasive is 1 nm to 1000 nm. The nano-abrasives used in the polishing slurry of the present application are nanoscale small-diameter particles. Small particle size reduces mechanical action, preventing excessive mechanical force from damaging the surface quality of the polished workpiece. Additionally, the particle size of the nano-abrasives also facilitates uniform and stable distribution of the abrasives in the polishing slurry, ensuring the stability of the polishing slurry and thus ensuring the consistency and controllability of the polishing effect. Exemplarily, the average particle size of the nano-abrasives can be any typical but non-limiting point value, such as 1 nm, 10 nm, 50 nm, 100 nm, 300 nm, 500 nm, 800 nm, or 1000 nm, or a range between any two of the foregoing values.

In some possible embodiments, a mass percentage of the nano-abrasive in the polishing slurry is 1% to 20%. When the mass percentage of the nano-abrasive in the polishing slurry is low, the number of abrasive particles participating in polishing per unit volume is small, reducing the contact opportunities between the abrasive particles and the workpiece surface, resulting in a low polishing removal rate. Furthermore, the larger distance between the abrasive particles prevents effective coverage of the workpiece surface, leading to uneven polishing and potentially uneven removal, resulting in poor polishing effect and high surface roughness. As the mass percentage of abrasive increases, the number of abrasive particles participating in polishing per unit volume increases, increasing the contact opportunities between the abrasive particles and the workpiece surface, gradually improving the polishing removal rate and enhancing the polishing effect. However, when the mass percentage of abrasive increases to a certain level, excessively high abrasive concentration can cause abrasive particles to accumulate and agglomerate during polishing, increasing the actual particle size of the abrasive particles involved in processing. This can cause new scratches and damage to the workpiece surface, leading to a decrease in the polished surface quality. In this embodiment, the mass percentage of nano-abrasives in the polishing slurry is 1% to 20%. This range ensures both the polishing efficiency and the surface quality of the workpiece. Furthermore, this mass percentage of abrasives provides the polishing slurry with a suitable concentration and good fluidity, making it suitable for gas-driven jet polishing. For example, the mass percentage of nano-abrasives in the polishing slurry can be any typical but non-limiting point value, such as 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, or 20%, or a range between any two of the foregoing values.

In some possible embodiments, the dispersion aid comprises at least one of a dispersant and a suspending agent. In this case, adding a dispersant to the polishing slurry can maintain a uniform distribution of abrasive particles within the slurry, avoiding localized high-concentration areas caused by abrasive particle aggregation, thereby ensuring a uniform polished surface. This helps reduce surface scratches and uneven wear caused by uneven abrasive particle distribution. Due to the uniform distribution of abrasive particles, the dispersant can also significantly reduce surface defects generated during polishing, such as microcracks and ripples, improving the smoothness and quality of the polished surface. The dispersant can also prevent abrasive particles and other particles from settling in the polishing slurry, maintaining the uniformity and stability of the slurry. This helps extend the service life of the polishing slurry and reduces waste and performance degradation caused by sedimentation. Adding a suspending agent to the polishing slurry can improve its resistance to settling, ensuring that abrasive particles are uniformly suspended in the slurry, thereby improving polishing efficiency and quality. The suspending agent can also improve the fluidity of the polishing slurry, making it easier for the slurry to distribute evenly on the polished surface, further improving the polishing effect.

In some possible embodiments, the solvent comprises water. In this case, using water as the solvent for the polishing slurry has minimal impact on the workpiece, and water itself is non-toxic and harmless, causing no environmental pollution. Therefore, using water as the solvent has advantages in many aspects, comprising environmental friendliness, safety, economy, ease of cleaning, and applicability.

In some possible embodiments, the dispersant comprises at least one selected from the group consisting of a sodium polyacrylate, a polyacrylamide, a tripolyphosphate salt, and sodium dodecylbenzenesulfonate. These dispersants can all improve the dispersion performance of nano-abrasives in the polishing slurry, thereby improving the polishing efficiency and polishing effect.

In some possible embodiments, in the polishing slurry, a mass percentage of the dispersant is 0.1% to 5%. Exemplary values can be any typical but non-limiting point value, such as 0.1%, 0.5%, 1%, 2%, 3%, 4%, and 5%, or a range between any two of the foregoing values. This content of dispersant can effectively improve the dispersion performance of nano-abrasives in the polishing slurry, thereby improving the polishing efficiency and polishing effect.

In some possible embodiments, the suspending agent comprises at least one selected from the group consisting of a carboxymethyl cellulose and a xanthan gum. These suspending agents can improve the anti-settling properties of the polishing slurry and enhance the flowability of the polishing slurry, thereby improving polishing efficiency and quality.

In some possible embodiments, in the polishing slurry, a mass percentage of the suspending agent is 0.1% to 5%. Exemplary values can be any typical but non-limiting point value, such as, such as 0.1%, 0.5%, 1%, 2%, 3%, 4%, and 5%, or a range between any two of the foregoing values. This concentration of suspending agent can improve the anti-settling properties and flowability of the polishing slurry, thereby improving polishing efficiency and quality.

In some embodiments, a dispersant, suspending agent, nano-abrasive, and water are thoroughly mixed to form a polishing slurry. The nano-abrasive can be nano-silicon dioxide abrasive or nano-cerium dioxide abrasive. After mixing, the mixture is ultrasonically agitated in an ultrasonic cleaner to ensure uniform dispersion of the nano-abrasive in the liquid, and then set aside.

In step S20:

In some possible embodiments, the step of polishing the surface to be polished of the workpiece comprises: immersing the workpiece and a gas flow nozzle in the polishing slurry, ejecting gas through the gas flow nozzle into the polishing slurry to form the gas jet, wherein an impact direction of the gas jet is directed toward the surface to be polished of the workpiece for polishing. In this case, the workpiece and the gas flow nozzle are additionally immersed in the polishing slurry. The gas ejected through the gas flow nozzle forms a high-velocity gas flow in the polishing slurry, creating a gas jet that drives the nanoparticles in the polishing slurry to impact the surface to be polished of the workpiece at high velocity, achieving efficient material removal. Additionally, the disturbance of the polishing slurry by the gas flow prevents abrasive sedimentation and improves the stability of the polishing slurry. Furthermore, since the abrasive does not pass through the nozzle, only the gas passes through, preventing nozzle wear and ensuring the durability and reliability of the apparatus.

The method for gas-driven jet polishing in embodiments of the present application differs from traditional purely mechanical polishing. The selected nano-abrasive particles introduce chemical reactions during polishing, achieving atomic-scale material removal and high surface quality through a combination of chemical action and mechanical impact. Furthermore, the immersion-type, gas-driven jet polishing method generates extremely high-velocity gas flow even under low pressure. This high-velocity gas flow accelerates the nano-abrasive particles, causing them to impact the workpiece surface at high velocity, resulting in highly efficient material removal. Based on the above, this solution requires only relatively low pressure, placing minimal demands on the pressure pump of the polishing system, thus reducing costs. Additionally, since the abrasive does not pass through the nozzle, only the gas passes through, preventing nozzle wear and ensuring the durability and reliability of the apparatus.

In some embodiments, the nozzle and workpiece are immersed in a polishing slurry, and then pressurized air is introduced into the nozzle to accelerate the abrasive particles in the polishing slurry and impact the workpiece surface.

In some possible embodiments, a distance between the surface to be polished of the workpiece and the gas flow nozzle is greater than 0 and less than or equal to 15 mm. In this case, the distance between the workpiece surface to be polished and the gas flow nozzle is more conducive to improving the polishing efficiency of the workpiece surface. Exemplarily, the distance between the workpiece surface to be polished and the gas flow nozzle can be any typical but non-limiting point value or an interval between any two point values, such as 1 mm, 2 mm, 3 mm, 5 mm, 8 mm, 10 mm, 12 mm, 13 mm, 14 mm, 15 mm, etc.

In some possible embodiments, an angle between the impact direction of the gas jet and the surface to be polished of the workpiece is greater than 0 and less than or equal to 90°. In this case, the angle between the impact direction of the air jet and the surface to be polished of the workpiece is beneficial to improving the polishing efficiency of the air jet on the workpiece, allowing the air jet to fully act on all areas of the surface to be polished of the workpiece. For example, the angle between the impact direction of the air jet and the surface to be polished of the workpiece can be any typical but non-limiting point value, such as, such as 0°, 10°, 20°, 30°, 40°, 50°, 60°, 70°, 80°, 90°, etc. or a range between any two of the foregoing values.

In some possible embodiments, a motion trajectory of the gas flow nozzle relative to the workpiece comprises a zigzag path, a spiral path, or an irregular path. In this case, the motion trajectory of the gas flow nozzle relative to the workpiece can be a regular zigzag path, a spiral path, etc., or an irregular random path, which fully ensures that the air jet drives the polishing slurry to polish the workpiece surface, thus ensuring polishing efficiency.

In some possible embodiments, a gas pressure at an outlet of the gas flow nozzle is greater than 0 and less than or equal to 4 bar. Since in embodiments of the present application, an immersion-type, gas-driven jet polishing method is adopted, an extremely high-velocity gas flow can be generated even under low pressure. This high-velocity gas flow accelerates the movement of the nano-abrasive particles, causing them to impact the workpiece surface at high velocity, resulting in efficient material removal. Therefore, the gas pressure at the outlet of the gas flow nozzle in embodiments of the present application is smaller than or equal to 4 bar, requiring only lower pressure and reducing the requirements for the pressure pump of the polishing system. This significantly reduces polishing costs while ensuring polishing efficiency. For example, the gas pressure at the outlet of the gas flow nozzle can be any typical but non-limiting point value, such as, such as bar, 2 bar, 3 bar, and 4 bar, or a range between any two of the foregoing values

In some possible embodiments, an outlet of the gas flow nozzle is configured in a pattern comprising a single orifice, multiple orifices, or a linear slit. In this case, the pattern of the outlet of the gas flow nozzle can be diverse, comprising a single orifice, multiple orifices, or a linear slit, etc., and different outlet shapes are suitable for different application requirements. Furthermore, for multi-hole outlet, different outlet directions can be constructed for different holes, allowing the polishing slurry to be driven in multiple directions to polish the workpiece.

In some embodiments, the method for gas-driven jet polishing comprises the following steps:

In step S11, a dispersant, a suspending agent, a nano-abrasive, and water are thoroughly mixed to form a polishing slurry. The nano-abrasive may be a nano-silicon dioxide abrasive or a nano-cerium dioxide abrasive. After mixing, the polishing slurry is ultrasonically agitated in an ultrasonic cleaner to ensure uniform dispersion of the nano-abrasive in the polishing slurry, and then set aside for use.

In step S21, immerse the workpiece and the gas flow nozzle in a gas-driven jet chemical mechanical polishing slurry. The distance between the nozzle outlet and the workpiece surface is adjustable within the range of 0-15 mm, and the angle between the nozzle and the workpiece surface is adjustable within the range of greater than 0 and smaller than or equal to 90 degrees. The pattern of outlet of the gas follow nozzle can be freely adjusted according to polishing requirements, comprising but not limited to a single orifice, multiple orifices, or a linear slit. Constant-pressure gas is ejected from the nozzle through a proportional valve. The outlet gas pressure can be controlled by a computer via an electromagnetic proportional valve, with a pressure range greater than 0 and less than or equal to 4 bar. The relative movement between the nozzle and the workpiece is controlled by a CNC motion system, and the motion trajectory comprises but is not limited to zigzag paths, spiral paths, and irregular paths.

S31. After polishing, the gas pressure at the outlet of the gas flow nozzle is adjusted to 0, the workpiece is then removed and cleaned to obtain a workpiece with high surface quality after polishing.

A second aspect of embodiments of the present application provide an apparatus for gas-driven jet polishing, as shown in FIG. 2, comprises:

• • a polishing container 8, configured to hold a polishing slurry 6 and a workpiece 4 which is to be polished;
  • a gas flow nozzle 3, configured to be immersed in the polishing slurry in the polishing container 8 during operation; and
  • a controller, configured to control a gas flow at an outlet of the gas flow nozzle 3 to form a gas jet toward the workpiece4 in the polishing slurry 6.

The apparatus for gas-driven jet polishing provided by embodiments of the present application comprises a polishing container 8, which holds a polishing slurry 6 and a workpiece 4 to be polished. The polishing process of the workpiece 4 takes place within the polishing container 8. The apparatus further comprises a gas flow nozzle 3, which is immersed in the polishing slurry 6 in the polishing container 8 during operation and can be removed from the polishing container 8 when not in operation. A controller controls the gas flow at the outlet of the gas flow nozzle 3 to form a gas jet in the polishing slurry 6 directed towards the workpiece 4. This accelerates the polishing effect of the abrasive particles in the polishing slurry 6 on the surface of the workpiece 4, achieving atomic-scale material removal and sub-nanometer surface roughness. This apparatus for gas-driven jet polishing can efficiently and effectively polish complex free-form surfaces, operates at low pressure, leading to low energy consumption and reduced process costs. Additionally, the polishing slurry 6 does not require pipeline transportation, reduces wear on the apparatus. It is also less prone to contamination, maintains a stable concentration, and allows for flexible control of the composition and concentration of the polishing slurry 6, significantly improving process efficiency. Furthermore, the apparatus for gas-driven jet polishing of the present application features simple equipment development, eliminates the need for a polishing slurry circulation system and a high-performance pressure pump, avoids valve and nozzle wear, and is low in cost.

In some possible embodiments, the polishing slurry 6 in the polishing container 8 can be flexibly replaced, and can be replaced by directly replacing the polishing container 8.

In some possible embodiments, the outlet of the gas flow nozzle 3 is oriented towards the workpiece 4. In this case, the gas flow from the outlet of the gas flow nozzle 3 forms a gas jet in the polishing slurry 6 directed towards the workpiece 4, accelerating the polishing effect of the abrasive particles in the polishing slurry 6 on the surface of the workpiece 4, achieving atomic-scale material removal and sub-nanometer surface roughness.

In some possible embodiments, the polishing container 8 further comprises a worktable 5, and the workpiece 4 is placed on the worktable. When the gas-driven jet polishing apparatus is operating, the workpiece 4 to be polished is fixed on the worktable 5, ensuring the stability of the polishing process.

In some possible embodiments, a distance between the gas flow nozzle 3 and a surface to be polished of the workpiece 4 is greater than 0 and not more than 15 mm. In this case, the distance between the surface to be polished of the workpiece 4 and the gas flow nozzle 3 is beneficial for improving the polishing efficiency of the workpiece 4 surface.

In some possible embodiments, the distance between the gas flow nozzle 3 and the surface to be polished of the workpiece 4 is 5 mm to 15 mm. In this case, the distance between the surface to be polished of the workpiece 4 and the gas flow nozzle 3 is more conducive to improving the polishing efficiency of the workpiece 4 surface.

In some possible embodiments, an angle between the gas flow nozzle 3 and a surface to be polished of the workpiece 4 is greater than 0 and less than or equal to 90°. In this case, the angle between the impact direction of the air jet and the surface to be polished of the workpiece 4 is conducive to improving the polishing efficiency of the air jet on the workpiece 4, allowing the air jet to fully act on all areas of the surface to be polished of the workpiece 4.

In some possible embodiments, the angle between the gas flow nozzle 3 and the surface to be polished of the workpiece 4 is 60° to 90°. In this case, the angle between the impact direction of the air jet and the surface to be polished of the workpiece 4 is more conducive to improving the polishing efficiency of the air jet on the workpiece 4.

In some possible embodiments, an outlet of the gas flow nozzle 3 is configured in a pattern comprising a single orifice, multiple orifices, or a linear slit. As shown in FIG. 3, part (1) is a single orifice pattern, part (2) to part (4) are multiple orifice pattern, and part (5) is a linear slit pattern. Different outlet patterns can be used to meet different application requirements.

In some possible embodiments, the controller comprises a gas flow controller 1 and a motion controller 2, the gas flow controller 1 is configured to control the gas flow from the outlet of the gas flow nozzle 3, and the motion controller 2 is configured to control a motion trajectory of the gas flow nozzle 3. In this case, the controller comprises both the gas flow controller 1 and the motion controller 2, which can additionally control the gas flow rate and pressure of the gas flow nozzle 3, as well as control the motion trajectory of the gas flow nozzle 3, to achieve a better polishing effect on the workpiece 4.

In some possible embodiments, the gas flow controller 1 and the gas flow nozzle 3 are connected via a gas tube 7.

In some possible embodiments, the gas flow controller 1 controls gas to eject from the gas flow nozzle 3 at a constant pressure greater than 0 and less than or equal to 4 bar. In this embodiment, the gas pressure at the outlet of the gas flow nozzle 3 is smaller than or equal to 4 bar, requiring only a lower pressure and reducing the requirements on the pressure pump of the polishing system. This significantly reduces polishing costs while ensuring polishing efficiency. Exemplarily, the gas pressure at the outlet of the gas flow nozzle 3 can be any typical but non-limiting point value, such as, such as bar, 2 bar, 3 bar, and 4 bar, or a range between any two of the foregoing values.

In some possible embodiments, the motion controller 2 regulates the motion trajectory of the gas flow nozzle 3 relative to the workpiece 4 as a zigzag path, a spiral path, or an irregular path. In this case, different motion trajectories ensure that the air jet drives the polishing slurry 6 to fully polish the surface of the workpiece 4, thus ensuring polishing efficiency.

Thirdly, embodiments of the present application provide a method for polishing an optically complex curved surface part. The method comprises: polishing the optically complex curved surface part using the method for gas-driven jet polishing as described in the above and/or the apparatus for gas-driven jet polishing as described in the above.

The method and the apparatus for gas-driven jet polishing of the above embodiments of the present application can achieve high surface quality on the workpiece 4, realize sub-nanometer surface roughness, high polishing efficiency, and low sub-surface damage. In addition, the polishing method and the polishing apparatus ensure uniform contact between the polishing medium and the complex surface, maintaining stable shape accuracy and uniform polished surface quality for optically complex curved surfaces, achieving ultra-precision machining and sub-nanometer-level surface roughness for optically complex curved surfaces.

To enable those skilled in the art to clearly understand the above-described implementation details and operations of the present application, and to demonstrate the significant improvement in the performance of the method and the apparatus for gas-driven jet polishing of the present application, the following examples illustrate the above technical solutions.

Example 1

A method for gas-driven jet polishing was performed using a polishing apparatus shown in FIG. 4 by the following steps:

1. Silicon dioxide particles (nano-abrasives) having a diameter of approximately 20 nm were thoroughly mixed with water. The mixture was then ultrasonically agitated in an ultrasonic cleaner to ensure uniform dispersion of the nano-abrasive in the liquid, forming a polishing slurry 6 having a nano-abrasive concentration of 10%.

2. A monocrystalline silicon workpiece 4 and a gas flow nozzle 3 were immersed in the polishing slurry 6. A distance between the outlet of the gas flow nozzle 3 and a surface of the monocrystalline silicon workpiece 4 was 1 mm, an angle between the gas flow nozzle 3 and the surface of the monocrystalline silicon workpiece 4 was 90 degrees, and the outlet of the gas flow nozzle 3 featured a single orifice pattern.

3. A gas flow controller 1 was connected to the gas flow nozzle 3 via a gas tube 7. Constant-pressure gas, regulated by the gas flow controller 1 through a proportional valve, was ejected from the gas flow nozzle 3. The gas pressure at the outlet of the gas flow nozzle 3 was controlled and maintained at 2 bar by a computer via an electromagnetic proportional valve.

4. A motion trajectory of the gas flow nozzle 3 relative to the monocrystalline silicon workpiece 4 was controlled by a motion controller 2 to follow a zigzag path.

5. Upon completion of polishing, the gas pressure at the outlet of the gas flow nozzle 3 was reduced to 0. The monocrystalline silicon workpiece 4 was then removed and cleaned, whereby a monocrystalline silicon workpiece 4 having high surface quality was obtained.

Example 2

A method for gas-driven jet polishing was performed using a polishing apparatus shown in FIG. 4 by the following steps:

1. Silicon dioxide particles (nano-abrasives) having a diameter of approximately 20 nm were thoroughly mixed with water. The mixture was then ultrasonically agitated in an ultrasonic cleaner to ensure uniform dispersion of the nano-abrasive in the liquid, forming a polishing slurry 6 having a nano-abrasive concentration of 10%.

2. An optical glass workpiece 4 and a gas flow nozzle 3 were immersed in the polishing slurry 6. A distance between the outlet of the gas flow nozzle 3 and a surface of the optical glass workpiece 4 was 1 mm, an angle between the gas flow nozzle 3 and the surface of the optical glass workpiece 4 was 90 degrees, and the outlet of the gas flow nozzle 3 featured a multi-orifice pattern.

3. A gas flow controller 1 was connected to the gas flow nozzle 3 via a gas tube 7. Constant-pressure gas, regulated by the gas flow controller 1 through a proportional valve, was ejected from the gas flow nozzle 3. The gas pressure at the outlet of the gas flow nozzle 3 was controlled and maintained at 2 bar by a computer via an electromagnetic proportional valve.

4. A motion trajectory of the gas flow nozzle 3 relative to the optical glass workpiece 4 was controlled by a motion controller 2 to follow an irregular path.

5. Upon completion of polishing, the gas pressure at the outlet of the gas flow nozzle 3 was reduced to 0. The optical glass workpiece 4 was then removed and cleaned, whereby an optical glass workpiece 4 having high surface quality was obtained.

Example 3

A method for gas-driven jet polishing was performed using a polishing apparatus shown in FIG. 4 by the following steps:

1. A 1% sodium polyacrylate dispersant, a 0.3% carboxymethyl cellulose suspending agent, and cerium dioxide particles (nano-abrasives) having a diameter of approximately 20 nm were thoroughly mixed with water. The mixture was then ultrasonically agitated in an ultrasonic cleaner to ensure uniform dispersion of the nano-abrasive in the liquid, forming a polishing slurry 6 having a nano-abrasive concentration of 10%.

2. A monocrystalline silicon workpiece 4 and a gas flow nozzle 3 were immersed in the polishing slurry 6. A distance between the outlet of the gas flow nozzle 3 and a surface of the monocrystalline silicon workpiece 4 was 1 mm, an angle between the gas flow nozzle 3 and the surface of the monocrystalline silicon workpiece 4 was 90 degrees, and the outlet of the gas flow nozzle 3 featured a single orifice pattern.

3. A gas flow controller 1 was connected to the gas flow nozzle 3 via a gas tube 7. Constant-pressure gas, regulated by the gas flow controller 1 through a proportional valve, was ejected from the gas flow nozzle 3. The gas pressure at the outlet of the gas flow nozzle 3 was controlled and maintained at 2 bar by a computer via an electromagnetic proportional valve.

4. A motion trajectory of the gas flow nozzle 3 relative to the monocrystalline silicon workpiece 4 was controlled by a motion controller 2 to follow a zigzag path.

5. Upon completion of polishing, the gas pressure at the outlet of the gas flow nozzle 3 was reduced to 0. The monocrystalline silicon workpiece 4 was then removed and cleaned, whereby a monocrystalline silicon workpiece 4 having high surface quality was obtained.

Example 4

A method for gas-driven jet polishing was performed using a polishing apparatus shown in FIG. 4 by the following steps:

1. Silicon dioxide particles (nano-abrasives) having a diameter of approximately 10 nm were thoroughly mixed with water. The mixture was then ultrasonically agitated in an ultrasonic cleaner to ensure uniform dispersion of the nano-abrasive in the liquid, forming a polishing slurry 6 having a nano-abrasive concentration of 10%.

2. A monocrystalline silicon workpiece 4 and a gas flow nozzle 3 were immersed in the polishing slurry 6. A distance between the outlet of the gas flow nozzle 3 and a surface of the monocrystalline silicon workpiece 4 was 1 mm, an angle between the gas flow nozzle 3 and the surface of the monocrystalline silicon workpiece 4 was 90 degrees, and the outlet of the gas flow nozzle 3 featured a single orifice pattern.

3. A gas flow controller 1 was connected to the gas flow nozzle 3 via a gas tube 7. Constant-pressure gas, regulated by the gas flow controller 1 through a proportional valve, was ejected from the gas flow nozzle 3. The gas pressure at the outlet of the gas flow nozzle 3 was controlled and maintained at 2 bar by a computer via an electromagnetic proportional valve.

4. A motion trajectory of the gas flow nozzle 3 relative to the monocrystalline silicon workpiece 4 was controlled by a motion controller 2 to follow a zigzag path.

5. Upon completion of polishing, the gas pressure at the outlet of the gas flow nozzle 3 was reduced to 0. The monocrystalline silicon workpiece 4 was then removed and cleaned, whereby a monocrystalline silicon workpiece 4 having high surface quality was obtained.

Example 5

A method for gas-driven jet polishing was performed using a polishing apparatus shown in FIG. 4 by the following steps:

1. Silicon dioxide particles (nano-abrasives) having a diameter of approximately 100 nm were thoroughly mixed with water. The mixture was then ultrasonically agitated in an ultrasonic cleaner to ensure uniform dispersion of the nano-abrasive in the liquid, forming a polishing slurry 6 having a nano-abrasive concentration of 10%.

2. A monocrystalline silicon workpiece 4 and a gas flow nozzle 3 were immersed in the polishing slurry 6. A distance between the outlet of the gas flow nozzle 3 and a surface of the monocrystalline silicon workpiece 4 was 1 mm, an angle between the gas flow nozzle 3 and the surface of the monocrystalline silicon workpiece 4 was 90 degrees, and the outlet of the gas flow nozzle 3 featured a single orifice pattern.

3. A gas flow controller 1 was connected to the gas flow nozzle 3 via a gas tube 7. Constant-pressure gas, regulated by the gas flow controller 1 through a proportional valve, was ejected from the gas flow nozzle 3. The gas pressure at the outlet of the gas flow nozzle 3 was controlled and maintained at 2 bar by a computer via an electromagnetic proportional valve.

4. A motion trajectory of the gas flow nozzle 3 relative to the monocrystalline silicon workpiece 4 was controlled by a motion controller 2 to follow a zigzag path.

5. Upon completion of polishing, the gas pressure at the outlet of the gas flow nozzle 3 was reduced to 0. The monocrystalline silicon workpiece 4 was then removed and cleaned, whereby a monocrystalline silicon workpiece 4 having high surface quality was obtained.

Example 6

A method for gas-driven jet polishing was performed using a polishing apparatus shown in FIG. 4 by the following steps:

1. A 1% sodium polyacrylate dispersant, a 0.3% carboxymethyl cellulose suspending agent, and silicon dioxide particles+cerium dioxide particles (nano-abrasives) having a diameter of approximately 10 nm were thoroughly mixed with water. The mixture was then ultrasonically agitated in an ultrasonic cleaner to ensure uniform dispersion of the nano-abrasives in the liquid, forming a polishing slurry 6 having a nano-abrasive concentration of 10%.

2. A monocrystalline silicon workpiece 4 and a gas flow nozzle 3 were immersed in the polishing slurry 6. A distance between the outlet of the gas flow nozzle 3 and a surface of the monocrystalline silicon workpiece 4 was 1 mm, an angle between the gas flow nozzle 3 and the surface of the monocrystalline silicon workpiece 4 was 90 degrees, and the outlet of the gas flow nozzle 3 featured a single orifice pattern.

3. A gas flow controller 1 was connected to the gas flow nozzle 3 via a gas tube 7. Constant-pressure gas, regulated by the gas flow controller 1 through a proportional valve, was ejected from the gas flow nozzle 3. The gas pressure at the outlet of the gas flow nozzle 3 was controlled and maintained at 2 bar by a computer via an electromagnetic proportional valve.

4. A motion trajectory of the gas flow nozzle 3 relative to the monocrystalline silicon workpiece 4 was controlled by a motion controller 2 to follow a zigzag path.

5. Upon completion of polishing, the gas pressure at the outlet of the gas flow nozzle 3 was reduced to 0. The monocrystalline silicon workpiece 4 was then removed and cleaned, whereby a monocrystalline silicon workpiece 4 having high surface quality was obtained.

Example 7

A method for gas-driven jet polishing was performed using a polishing apparatus shown in FIG. 4 by the following steps:

1. Silicon dioxide particles (nano-abrasives) having a diameter of approximately 20 nm were thoroughly mixed with water. The mixture was then ultrasonically agitated in an ultrasonic cleaner to ensure uniform dispersion of the nano-abrasive in the liquid, forming a polishing slurry 6 having a nano-abrasive concentration of 5%.

2. A monocrystalline silicon workpiece 4 and a gas flow nozzle 3 were immersed in the polishing slurry 6. A distance between the outlet of the gas flow nozzle 3 and a surface of the monocrystalline silicon workpiece 4 was 1 mm, an angle between the gas flow nozzle 3 and the surface of the monocrystalline silicon workpiece 4 was 90 degrees, and the outlet of the gas flow nozzle 3 featured a single orifice pattern.

3. A gas flow controller 1 was connected to the gas flow nozzle 3 via a gas tube 7. Constant-pressure gas, regulated by the gas flow controller 1 through a proportional valve, was ejected from the gas flow nozzle 3. The gas pressure at the outlet of the gas flow nozzle 3 was controlled and maintained at 2 bar by a computer via an electromagnetic proportional valve.

4. A motion trajectory of the gas flow nozzle 3 relative to the monocrystalline silicon workpiece 4 was controlled by a motion controller 2 to follow a zigzag path.

5. Upon completion of polishing, the gas pressure at the outlet of the gas flow nozzle 3 was reduced to 0. The monocrystalline silicon workpiece 4 was then removed and cleaned, whereby a monocrystalline silicon workpiece 4 having high surface quality was obtained.

Example 8

A method for gas-driven jet polishing was performed using a polishing apparatus shown in FIG. 4 by the following steps:

1. Silicon dioxide particles (nano-abrasives) having a diameter of approximately 20 nm were thoroughly mixed with water. The mixture was then ultrasonically agitated in an ultrasonic cleaner to ensure uniform dispersion of the nano-abrasive in the liquid, forming a polishing slurry 6 having a nano-abrasive concentration of 20%.

2. A monocrystalline silicon workpiece 4 and a gas flow nozzle 3 were immersed in the polishing slurry 6. A distance between the outlet of the gas flow nozzle 3 and a surface of the monocrystalline silicon workpiece 4 was 1 mm, an angle between the gas flow nozzle 3 and the surface of the monocrystalline silicon workpiece 4 was 90 degrees, and the outlet of the gas flow nozzle 3 featured a single orifice pattern.

3. A gas flow controller 1 was connected to the gas flow nozzle 3 via a gas tube 7. Constant-pressure gas, regulated by the gas flow controller 1 through a proportional valve, was ejected from the gas flow nozzle 3. The gas pressure at the outlet of the gas flow nozzle 3 was controlled and maintained at 2 bar by a computer via an electromagnetic proportional valve.

4. A motion trajectory of the gas flow nozzle 3 relative to the monocrystalline silicon workpiece 4 was controlled by a motion controller 2 to follow a zigzag path.

5. Upon completion of polishing, the gas pressure at the outlet of the gas flow nozzle 3 was reduced to 0. The monocrystalline silicon workpiece 4 was then removed and cleaned, whereby a monocrystalline silicon workpiece 4 having high surface quality was obtained.

Example 9

A method for gas-driven jet polishing was performed using a polishing apparatus shown in FIG. 4 by the following steps:

1. Silicon dioxide particles (nano-abrasives) having a diameter of approximately 20 nm were thoroughly mixed with water. The mixture was then ultrasonically agitated in an ultrasonic cleaner to ensure uniform dispersion of the nano-abrasive in the liquid, forming a polishing slurry 6 having a nano-abrasive concentration of 5%.

2. A monocrystalline silicon workpiece 4 and a gas flow nozzle 3 were immersed in the polishing slurry 6. A distance between the outlet of the gas flow nozzle 3 and a surface of the monocrystalline silicon workpiece 4 was 10 mm, an angle between the gas flow nozzle 3 and the surface of the monocrystalline silicon workpiece 4 was 90 degrees, and the outlet of the gas flow nozzle 3 featured a single orifice pattern.

3. A gas flow controller 1 was connected to the gas flow nozzle 3 via a gas tube 7. Constant-pressure gas, regulated by the gas flow controller 1 through a proportional valve, was ejected from the gas flow nozzle 3. The gas pressure at the outlet of the gas flow nozzle 3 was controlled and maintained at 2 bar by a computer via an electromagnetic proportional valve.

4. A motion trajectory of the gas flow nozzle 3 relative to the monocrystalline silicon workpiece 4 was controlled by a motion controller 2 to follow a zigzag path.

5. Upon completion of polishing, the gas pressure at the outlet of the gas flow nozzle 3 was reduced to 0. The monocrystalline silicon workpiece 4 was then removed and cleaned, whereby a monocrystalline silicon workpiece 4 having high surface quality was obtained.

Example 10

A method for gas-driven jet polishing was performed using a polishing apparatus shown in FIG. 4 by the following steps:

1. Silicon dioxide particles (nano-abrasives) having a diameter of approximately 20 nm were thoroughly mixed with water. The mixture was then ultrasonically agitated in an ultrasonic cleaner to ensure uniform dispersion of the nano-abrasive in the liquid, forming a polishing slurry 6 having a nano-abrasive concentration of 5%.

2. A monocrystalline silicon workpiece 4 and a gas flow nozzle 3 were immersed in the polishing slurry 6. A distance between the outlet of the gas flow nozzle 3 and a surface of the monocrystalline silicon workpiece 4 was 15 mm, an angle between the gas flow nozzle 3 and the surface of the monocrystalline silicon workpiece 4 was 90 degrees, and the outlet of the gas flow nozzle 3 featured a single orifice pattern.

3. A gas flow controller 1 was connected to the gas flow nozzle 3 via a gas tube 7. Constant-pressure gas, regulated by the gas flow controller 1 through a proportional valve, was ejected from the gas flow nozzle 3. The gas pressure at the outlet of the gas flow nozzle 3 was controlled and maintained at 2 bar by a computer via an electromagnetic proportional valve.

4. A motion trajectory of the gas flow nozzle 3 relative to the monocrystalline silicon workpiece 4 was controlled by a motion controller 2 to follow a zigzag path.

5. Upon completion of polishing, the gas pressure at the outlet of the gas flow nozzle 3 was reduced to 0. The monocrystalline silicon workpiece 4 was then removed and cleaned, whereby a monocrystalline silicon workpiece 4 having high surface quality was obtained.

Example 11

A method for gas-driven jet polishing was performed using a polishing apparatus shown in FIG. 4 by the following steps:

1. Silicon dioxide particles (nano-abrasives) having a diameter of approximately 20 nm were thoroughly mixed with water. The mixture was then ultrasonically agitated in an ultrasonic cleaner to ensure uniform dispersion of the nano-abrasive in the liquid, forming a polishing slurry 6 having a nano-abrasive concentration of 5%.

2. A monocrystalline silicon workpiece 4 and a gas flow nozzle 3 were immersed in the polishing slurry 6. A distance between the outlet of the gas flow nozzle 3 and a surface of the monocrystalline silicon workpiece 4 was 10 mm, an angle between the gas flow nozzle 3 and the surface of the monocrystalline silicon workpiece 4 was 60 degrees, and the outlet of the gas flow nozzle 3 featured a single orifice pattern.

3. A gas flow controller 1 was connected to the gas flow nozzle 3 via a gas tube 7. Constant-pressure gas, regulated by the gas flow controller 1 through a proportional valve, was ejected from the gas flow nozzle 3. The gas pressure at the outlet of the gas flow nozzle 3 was controlled and maintained at 2 bar by a computer via an electromagnetic proportional valve.

4. A motion trajectory of the gas flow nozzle 3 relative to the monocrystalline silicon workpiece 4 was controlled by a motion controller 2 to follow a zigzag path.

5. Upon completion of polishing, the gas pressure at the outlet of the gas flow nozzle 3 was reduced to 0. The monocrystalline silicon workpiece 4 was then removed and cleaned, whereby a monocrystalline silicon workpiece 4 having high surface quality was obtained.

Example 12

A method for gas-driven jet polishing was performed using a polishing apparatus shown in FIG. 4 by the following steps:

1. Silicon dioxide particles (nano-abrasives) having a diameter of approximately 20 nm were thoroughly mixed with water. The mixture was then ultrasonically agitated in an ultrasonic cleaner to ensure uniform dispersion of the nano-abrasive in the liquid, forming a polishing slurry 6 having a nano-abrasive concentration of 5%.

2. A monocrystalline silicon workpiece 4 and a gas flow nozzle 3 were immersed in the polishing slurry 6. A distance between the outlet of the gas flow nozzle 3 and a surface of the monocrystalline silicon workpiece 4 was 10 mm, an angle between the gas flow nozzle 3 and the surface of the monocrystalline silicon workpiece 4 was 30 degrees, and the outlet of the gas flow nozzle 3 featured a single orifice pattern.

3. A gas flow controller 1 was connected to the gas flow nozzle 3 via a gas tube 7. Constant-pressure gas, regulated by the gas flow controller 1 through a proportional valve, was ejected from the gas flow nozzle 3. The gas pressure at the outlet of the gas flow nozzle 3 was controlled and maintained at 2 bar by a computer via an electromagnetic proportional valve.

4. A motion trajectory of the gas flow nozzle 3 relative to the monocrystalline silicon workpiece 4 was controlled by a motion controller 2 to follow a zigzag path.

5. Upon completion of polishing, the gas pressure at the outlet of the gas flow nozzle 3 was reduced to 0. The monocrystalline silicon workpiece 4 was then removed and cleaned, whereby a monocrystalline silicon workpiece 4 having high surface quality was obtained.

Example 13

A method for gas-driven jet polishing was performed using a polishing apparatus shown in FIG. 4 by the following steps:

1. Silicon dioxide particles (nano-abrasives) having a diameter of approximately 20 nm were thoroughly mixed with water. The mixture was then ultrasonically agitated in an ultrasonic cleaner to ensure uniform dispersion of the nano-abrasive in the liquid, forming a polishing slurry 6 having a nano-abrasive concentration of 5%.

2. A monocrystalline silicon workpiece 4 and a gas flow nozzle 3 were immersed in the polishing slurry 6. A distance between the outlet of the gas flow nozzle 3 and a surface of the monocrystalline silicon workpiece 4 was 10 mm, an angle between the gas flow nozzle 3 and the surface of the monocrystalline silicon workpiece 4 was 90 degrees, and the outlet of the gas flow nozzle 3 featured a single orifice pattern.

3. A gas flow controller 1 was connected to the gas flow nozzle 3 via a gas tube 7. Constant-pressure gas, regulated by the gas flow controller 1 through a proportional valve, was ejected from the gas flow nozzle 3. The gas pressure at the outlet of the gas flow nozzle 3 was controlled and maintained at 1 bar by a computer via an electromagnetic proportional valve.

4. A motion trajectory of the gas flow nozzle 3 relative to the monocrystalline silicon workpiece 4 was controlled by a motion controller 2 to follow a zigzag path.

5. Upon completion of polishing, the gas pressure at the outlet of the gas flow nozzle 3 was reduced to 0. The monocrystalline silicon workpiece 4 was then removed and cleaned, whereby a monocrystalline silicon workpiece 4 having high surface quality was obtained.

Example 14

A method for gas-driven jet polishing was performed using a polishing apparatus shown in FIG. 4 by the following steps:

1. Silicon dioxide particles (nano-abrasives) having a diameter of approximately 20 nm were thoroughly mixed with water. The mixture was then ultrasonically agitated in an ultrasonic cleaner to ensure uniform dispersion of the nano-abrasive in the liquid, forming a polishing slurry 6 having a nano-abrasive concentration of 5%.

2. A monocrystalline silicon workpiece 4 and a gas flow nozzle 3 were immersed in the polishing slurry 6. A distance between the outlet of the gas flow nozzle 3 and a surface of the monocrystalline silicon workpiece 4 was 10 mm, an angle between the gas flow nozzle 3 and the surface of the monocrystalline silicon workpiece 4 was 90 degrees, and the outlet of the gas flow nozzle 3 featured a single orifice pattern.

3. A gas flow controller 1 was connected to the gas flow nozzle 3 via a gas tube 7. Constant-pressure gas, regulated by the gas flow controller 1 through a proportional valve, was ejected from the gas flow nozzle 3. The gas pressure at the outlet of the gas flow nozzle 3 was controlled and maintained at 4 bar by a computer via an electromagnetic proportional valve.

4. A motion trajectory of the gas flow nozzle 3 relative to the monocrystalline silicon workpiece 4 was controlled by a motion controller 2 to follow a zigzag path.

5. Upon completion of polishing, the gas pressure at the outlet of the gas flow nozzle 3 was reduced to 0. The monocrystalline silicon workpiece 4 was then removed and cleaned, whereby a monocrystalline silicon workpiece 4 having high surface quality was obtained.

Comparative Example 1

A waterjet polishing method was performed using cerium oxide polishing powder abrasive with a diameter of 1 μm. A polishing slurry having an abrasive concentration of 10% was used to directly polish the surface of a glass workpiece using waterjet polishing. The polishing pressure was 4 bar, the distance was 4 mm, the angle was 90°, and the outlet of the waterjet was a single orifice pattern.

The relevant parameters of the method for gas-driven jet polishing and polishing apparatus described in the above examples are shown in Table 1 below:

	TABLE 1
	Abrasive	Workpiece and	Nozzle

Particle

Nozzle

Outlet

Outlet

Workpiece

	Type	Size/nm	Concentration/%	Distance/mm	Angle/°	Path	pattern	Pressure/bar	Type

Example	Silicon	20	10	1	90	Zigzag	Single	2	Monocrystalline
1	dioxide						orifice		Silicon
Example	Silicon	20	10	1	90	Irregular	Multi-	2	Glass
2	dioxide						orifice
Example	Cerium	20	10	1	90	Zigzag	Single	2	Monocrystalline
3	Dioxide						orifice		Silicon
Example	Silicon	10	10	1	90	Zigzag	Single	2	Monocrystalline
4	dioxide						orifice		Silicon
Example	Silicon	100	10	1	90	Zigzag	Single	2	Monocrystalline
5	dioxide						orifice		Silicon
Example	Silicon	20	10	1	90	Zigzag	Single	2	Monocrystalline
6	dioxide,						orifice		Silicon
	Cerium
	Dioxide
Example	Silicon	20	5	1	90	Zigzag	Single	2	Monocrystalline
7	dioxide						orifice		Silicon
Example	Silicon	20	20	1	90	Zigzag	Single	2	Monocrystalline
8	dioxide						orifice		Silicon
Example	Silicon	20	10	10	90	Zigzag	Single	2	Monocrystalline
9	dioxide						orifice		Silicon
Example10	Silicon	20	10	15	90	Zigzag	Single	2	Monocrystalline
	dioxide						orifice		Silicon
Example	Silicon	20	10	1	60	Zigzag	Single	2	Monocrystalline
11	dioxide						orifice		Silicon
Example	Silicon	20	10	1	30	Zigzag	Single	2	Monocrystalline
12	dioxide						orifice		Silicon
Example	Silicon	20	10	1	90	Zigzag	Single	1	Monocrystalline
13	dioxide						orifice		Silicon
Example	Silicon	20	10	1	90	Zigzag	Single	4	Monocrystalline
14	dioxide						orifice		Silicon

To verify the progressiveness of the examples of the present application, the surface roughness of the workpieces after polishing in the above examples and comparative examples was tested, as shown below:

The morphology of the monocrystalline silicon workpiece of Example 1 and the glass workpiece of Example 2 after surface polishing are shown in FIGS. 5 and 6, respectively.

The surface roughness, polishing efficiency, and surface damage of the workpieces in each example and comparative example after polishing are shown in Table 2 below:

	TABLE 2
		Polishing
	Surface	Efficiency/106
	Roughness/nm	μm3/min	Surface Damage

Example 1	0.28	0.8	None
Example 2	0.32	4.3	None
Example 3	0.35	1.2	None
Example 4	0.30	0.6	None
Example 5	0.52	1.0	Very Few Pits
Example 6	0.36	0.9	None
Example 7	0.35	0.4	None
Example 8	0.42	1.6	None
Example 9	0.75	1.0	None
Example 10	0.53	0.8	None
Example 11	0.32	0.9	None
Example 12	0.30	0.8	None
Example 13	0.28	0.5	None
Example 14	0.62	1.3	Few Pits
Comparative	8.45	0.5	Numerous pits
Example 1

As can be seen from the above test results, the method and the apparatus for gas-driven jet polishing of the present application additionally achieve sub-nanometer-level surface roughness, high polishing efficiency, and extremely low subsurface damage. Furthermore, the test results demonstrate that the method and the apparatus for gas-driven jet polishing of the present application have significant advantages over traditional water jet polishing methods and can be well applied to the final surface finishing process of high-end optical components.

The above description is merely a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present application should be included within the scope of protection of the present application.