Micro-engine blade temperature control ultrasonic composite liquid gallium assisted grinding device and method

Abstract

The application belongs to the technical field of liquid metal coating and infiltration in grinding processing, and particularly relates to a micro-engine blade temperature control ultrasonic composite liquid gallium auxiliary grinding device and method. The device comprises a fluid delivery module, a temperature adjusting module, a processing module, an ultrasonic vibration module and an electromagnetic field generator. The temperature control of liquid gallium is realized by setting a microwave cavity and a cooling system. The stable supply is ensured by using inert gas and liquid gallium delivery pipelines. The uniform coating and ultrasonic vibration infiltration of the surface of the micro-engine blade are realized by combining an ultrasonic transducer assembly and a spraying nozzle. The electromagnetic field generator further enhances the adhesion and lubrication effect of liquid gallium on the grinding wheel and the blade. The application overcomes the defects of temperature control and lubrication deficiency of the traditional grinding wheel, effectively reduces the grinding temperature rise and the friction coefficient, avoids thermal damage and surface deformation, and improves the machining precision and surface quality of complex curved surfaces and tenon tooth parts.

Description

Technical Field

[0001] This application belongs to the field of liquid metal coating and wetting technology in grinding processes, and specifically relates to a temperature-controlled ultrasonic composite liquid gallium-assisted grinding device and method for micro engine blades. Background Technology

[0002] Miniature engine blades are widely used in high-temperature, high-speed operating equipment such as aero engines and gas turbines. Their complex structure and precise dimensions mean that machining accuracy and surface quality directly affect the overall performance, energy efficiency, and long-term operational reliability of the machine. The requirements for precision and surface integrity are particularly stringent during the machining of critical structural components such as blade tenons.

[0003] Currently, the grinding of micro-engine blades still primarily employs traditional grinding wheel methods. However, traditional grinding wheels generate significant frictional heat during the grinding process, leading to increased blade surface temperature. This, in turn, causes changes in the microstructure of the material surface, and can even result in thermal damage and deformation. This thermal effect not only hinders high-precision grinding control of complex curved surfaces but also significantly impacts the blade's mechanical properties, fatigue life, and operational safety. Furthermore, traditional machining methods struggle to reduce blade surface roughness, failing to meet the increasingly stringent manufacturing requirements for high-performance components.

[0004] In recent years, liquid metals, especially gallium-based liquid metal materials, have attracted widespread attention in advanced manufacturing due to their excellent physicochemical properties, such as being liquid at room temperature, low toxicity, low melting point, and high thermal and electrical conductivity. When exposed to an oxygen-containing environment, liquid metals can rapidly form a self-stabilizing oxide film. While this film slightly affects the wettability and rheology of the liquid metal, it has minimal impact on its thermal conductivity, maintaining good heat exchange efficiency. When used in combination with elastomer materials, liquid metals can effectively fill the elastomer structure through microscale droplets and suspension structures, achieving significant toughening and increasing the material's fracture energy by tens of times.

[0005] Applying liquid metal to the grinding of micro-blades holds promise for solving the problems of high temperature, insufficient lubrication, and low processing efficiency in traditional machining processes. The excellent fluidity and filling properties of liquid metal allow it to penetrate into the micro-cracks and gaps on the blade surface, providing both cooling and lubrication during grinding. This effectively reduces grinding temperature and the coefficient of friction, improving machining quality and precision.

[0006] However, existing liquid metal-assisted machining technologies still face many challenges in practical applications. Especially when coating micro-thin-walled grinding wheels with liquid gallium, the high fluidity and difficulty in precisely controlling the surface tension of the liquid metal easily lead to uneven coating and incomplete wetting. Particularly in the complex turbine blade tenon and tooth areas, the liquid metal cannot achieve effective coverage and lubrication, affecting its adaptability to high-precision machining and hindering the further promotion and application of liquid metal technology in the field of micro-precision grinding. Summary of the Invention

[0007] To address the technical problems existing in the grinding of micro-engine blades, such as high frictional heat, high temperature rise, easy damage and deformation of blade surface structure, uneven liquid metal coating, poor wettability, and insufficient cooling and lubrication, this application provides a temperature-controlled ultrasonic composite liquid gallium-assisted grinding device and method for micro-engine blades. Through gas-liquid co-pipe mixing and ultrasonic cavitation, liquid gallium is formed into micro-droplets and uniformly covers the blade surface and crack area. It has both efficient cooling and lubrication functions, effectively reducing grinding temperature rise and friction coefficient, avoiding damage and deformation, thereby improving the precision, surface quality and reliability of blade grinding.

[0008] On one hand, the micro-engine blade temperature-controlled ultrasonic composite liquid gallium-assisted grinding device provided in this application includes a fluid transport module, a temperature control module, a processing module, an ultrasonic vibration module, and an electromagnetic field generator; the temperature control module includes a microwave cavity, a tank, and a cooling system, both of which are hollow cylindrical annular structures, with the microwave cavity nested inside the tank, forming a closed annular cooling cavity between them; the inlet and outlet of the cooling system are respectively connected to the cooling cavity through the side wall of the tank; the bottom of the tank is provided with a composite liquid gallium outlet;

[0009] The fluid delivery module includes a gas storage tank, a liquid storage tank, an air inlet pipe, and a liquid inlet pipe. Both the gas storage tank and the liquid storage tank are located outside the tank body. The gas storage tank is filled with inert gas, and the liquid storage tank contains liquid gallium. One end of the air inlet pipe is connected to the gas outlet of the gas storage tank, and the other end passes through the side wall of the tank body and wraps around the outer wall of the microwave cavity before connecting to the composite liquid gallium outlet at the bottom of the tank body. One end of the liquid inlet pipe is connected to the liquid outlet of the liquid storage tank, and the other end passes through the side wall of the tank body and wraps around the outer wall of the microwave cavity before connecting to the lower end of the air inlet pipe.

[0010] The ultrasonic vibration module includes an ultrasonic vibration module housing, an ultrasonic transducer assembly, and a spray nozzle. The ultrasonic vibration module housing is vertically continuous, and its top is connected to the composite liquid gallium outlet channel of the tank. One end of the ultrasonic transducer assembly is located inside the ultrasonic cavity, and the other end extends out of the bottom of the ultrasonic cavity. The ultrasonic transducer assembly includes an ultrasonic generator, an ultrasonic frequency regulator, an ultrasonic amplitude regulator, an ultrasonic transducer, and an ultrasonic conduit. The ultrasonic generator is located at the upper end of the ultrasonic transducer assembly. The ultrasonic frequency regulator and the ultrasonic amplitude regulator are integrated with the ultrasonic generator through an embedded electrical connection. The ultrasonic transducer is installed at the bottom of the ultrasonic generator. The upper end of the ultrasonic conduit is connected to the ultrasonic transducer, and the lower end is connected to the spray nozzle. A lateral liquid inlet is provided on the side wall of the upper region of the ultrasonic conduit.

[0011] The electromagnetic field generator adopts a surround structure and is fixedly installed on the lower outer wall of the ultrasonic duct and adjacent to the spray nozzle.

[0012] Below the spray nozzle is a micro-engine blade to be processed. The micro-engine blade is fixed on the processing module, which includes a thin-walled grinding wheel made of nickel-based alloy.

[0013] In a preferred embodiment, the temperature-regulating tank further adopts a multi-segment composite structure, consisting of a cylindrical cavity, a hemispherical shell, and a conical shell connected sequentially from top to bottom; wherein, the cylindrical cavity is the upper main cavity, used to accommodate the microwave cavity, and its lower end is sealed to the hemispherical shell; the top of the hemispherical shell is connected to the bottom of the cylindrical cavity, and its spherical surface is facing downwards; the bottom of the hemispherical shell is provided with a gas-liquid mixture outlet communicating with the conical shell, and the gas-liquid mixture outlet is connected to the end of the liquid inlet pipe; the conical shell tapers downwards along the axial direction, with its cone angle facing downwards, forming a conical discharge outlet structure.

[0014] In a preferred embodiment, the fluid delivery module further includes a stirring blade and a motor. The motor is disposed at the center of the bottom inner side of the hemispherical shell of the temperature-regulating tank through its housing. The output shaft of the motor extends downward from the central axis position at the bottom of the hemispherical shell and is connected to the upper end of the stirring blade. The stirring blade is disposed on the outer side of the bottom of the hemispherical shell of the temperature-regulating tank and is located inside the conical shell of the temperature-regulating tank.

[0015] In a preferred embodiment, the ultrasonic vibration module further includes a filter screen and a blade guide wheel; the ultrasonic vibration module housing has a vertically penetrating ultrasonic cavity, which is a cylindrical cavity; the filter screen is disposed on the top inner side of the ultrasonic cavity and fixed to the inner wall of the cavity; the blade guide wheel is disposed in the middle region of the ultrasonic cavity; and the ultrasonic transducer assembly is located below the blade guide wheel.

[0016] In a preferred embodiment, the electromagnetic field generator further includes a current regulator and an electromagnetic coil, the electromagnetic coil being mounted around the lower end region of the ultrasonic conduit, and the current regulator being connected to one side of the electromagnetic coil.

[0017] In a preferred embodiment, a nozzle cleaning device is further included, which is installed at the bottom of the ultrasonic cavity.

[0018] In a preferred embodiment, the spraying distance between the nozzle of the spraying head and the processed surface of the micro-engine blade is further 50-100mm.

[0019] In a preferred embodiment, the fluid delivery module, temperature control module, ultrasonic vibration module, and electromagnetic field generator constitute an integrated operating unit, wherein the temperature control tank of the temperature control module is used to connect to an external lifting device.

[0020] In a preferred embodiment, the nozzle diameter of the spray head is further 80-300 μm.

[0021] On the other hand, the present invention also provides a method for a micro-engine blade temperature-controlled ultrasonic composite liquid gallium-assisted grinding device as described in any one of the above claims, the method comprising:

[0022] Step 1: Using the fluid transport module, gaseous and liquid gallium metal are introduced from the gas tank and liquid tank respectively. The gaseous and liquid gallium metal are transported to the temperature control module through the gas inlet pipe and liquid inlet pipe respectively, forming independent gas phase flow and liquid phase flow respectively.

[0023] Step 2: Liquid gallium metal is cooled to below its partial melting point by a cooling system in a temperature control module, causing some components to precipitate microcrystals and form a slush-like gallium metal containing solid microcrystals and liquid metal. The slush-like gallium metal is then heated to a preset temperature slightly above its melting point by a non-contact heating method set in a microwave cavity to achieve local melting and maintain the overall slush-like state.

[0024] Step 3: The slush-like metal and gas are mixed at the ends of the liquid inlet pipe and the gas inlet pipe respectively to form a uniform gas-liquid composite mixture, which is then introduced into the stirring area at the bottom of the temperature control module. With the help of stirring blades, it is subjected to high-speed shearing and rotational dispersion to form a stable three-phase distribution mixed medium.

[0025] Step 4: The stirred gas-liquid composite mixture flows into the ultrasonic vibration module, and the undispersed agglomerated particles and large bubbles are intercepted and separated by the filter screen structure set on the inner side of the top of the ultrasonic cavity. The filtered mixed fluid is guided by the blade guide wheel assembly to rotate downward along the tangential direction to the ultrasonic excitation area.

[0026] Step 5: After the mixed fluid enters the ultrasonic transducer, it is subjected to high-frequency ultrasonic excitation at a set frequency and amplitude to generate dense cavitation bubbles, microjets and acoustic flow disturbances, so as to destroy the oxide film structure on the surface of the mixed liquid and the solid phase aggregates in the fluid, so as to disperse them into finer micron film particles and form a uniform and dense pre-film layer.

[0027] Step 6: An electromagnetic field generator is installed on the outer wall of the ultrasonic catheter to generate eddies and Lorentz force fields in the conductive liquid using an alternating magnetic field, so as to control the internal flow circulation and direction of the mixed liquid metal.

[0028] Step 7: The composite liquid metal is sprayed onto the surface of the micro-engine blade in the form of a micro-beam through a spray nozzle located at the bottom of the ultrasonic conduit. After the film is formed, the temperature control module is moved upward by an external lifting device, and the grinding wheel system in the processing module is started to perform precision grinding on the sprayed area.

[0029] The beneficial effects of this application are:

[0030] First, the micro-engine blade temperature-controlled ultrasonic composite liquid gallium-assisted grinding device of this application addresses the problems in existing technologies, such as the generation of excessive frictional heat in traditional grinding wheel grinding, leading to excessive temperature rise on the blade surface, damage and deformation of the microstructure, uneven coating of liquid metal, and poor lubrication and cooling effects. It achieves parallel mixing of inert or reducing gas and liquid gallium through a fluid delivery module, forming a composite liquid gallium at the intersection of the air inlet pipe and the liquid inlet pipe. The high-speed gas flow and turbulent mixing not only improve the dispersion and fluidity of the liquid gallium but also effectively inhibit or remove the oxide film, ensuring the chemical stability and wettability of the liquid metal. Furthermore, the composite liquid... After entering the ultrasonic vibration module, the gallium metal is excited by the high-frequency ultrasonic transducer, generating a strong cavitation effect and surface disturbance. The liquid gallium is decomposed into a large number of microdroplets, accompanied by the synergistic effect of microbubbles, which enables it to quickly penetrate and uniformly cover the surface of the micro-engine blades and the microcrack area. Due to the excellent thermal conductivity and lubricity of liquid gallium itself, under the cavitation enhancement and gas-liquid synergistic effect, the composite liquid gallium metal can reduce the friction coefficient between the grinding wheel and the blade, quickly remove the frictional heat generated during the grinding process, thereby effectively reducing the temperature rise of the blade surface, avoiding thermal damage and deformation of the microstructure, and improving the surface quality and reliability of the grinding process.

[0031] Secondly, in the preferred implementation, the temperature-regulating tank of this application adopts a multi-segment composite structure design consisting of a cylindrical cavity, a hemispherical shell, and a conical shell connected in sequence. This design ensures that the upper cylindrical cavity can effectively accommodate the microwave cavity, while the hemispherical shell enables uniform force distribution and smooth fluid transition. Combined with the gradually converging structure of the conical shell, the gas-liquid mixture can be efficiently concentrated and smoothly discharged, thereby improving heat and mass transfer efficiency, reducing dead zones in flow, enhancing the overall stability and sealing of the system, and ultimately improving the service life and operational reliability of the temperature-regulating tank.

[0032] Third, in the preferred implementation, the motor of the fluid delivery module of this application is fixed to the center of the bottom of the hemispherical shell of the temperature regulating tank through the housing, which allows the output shaft to be directly centered and connected to the stirring blade, thereby ensuring that the stirring blade rotates uniformly inside the conical shell and improving the fluid stirring efficiency; at the same time, the stirring blade is located inside the conical shell of the tank, which not only facilitates the full mixing of the fluid in the tank, but also reduces sedimentation and promotes the uniformity of heat transfer, thus enhancing the overall stability and reliability of fluid delivery and temperature regulation.

[0033] Fourth, in the preferred implementation, this application arranges a filter screen, a blade guide wheel, and an ultrasonic transducer assembly sequentially within the cylindrical ultrasonic cavity. This ensures that the fluid entering the cavity first passes through the filter screen to effectively remove impurities, guaranteeing the purity of the medium. The blade guide wheel, located in the central region, guides and disperses the fluid flow, thereby improving the uniformity of the ultrasonic action. The ultrasonic transducer assembly, located below the blade guide wheel, enables more efficient ultrasonic vibration processing in the stable fluid environment after purification and guidance.

[0034] Fifth, in the preferred embodiment, the electromagnetic coil of this application is arranged around the lower periphery of the ultrasonic conduit. Under the control of the current regulator, it can generate an electromagnetic field of controllable intensity, which can directionally act on or assist in the regulation of fluid or particles in the ultrasonic conduit, thereby enhancing the ultrasonic effect. At the same time, through the flexible adjustment of the current regulator, the electromagnetic field intensity can be precisely controlled.

[0035] Sixth, in the preferred implementation, this application provides a nozzle cleaning device at the bottom of the ultrasonic cavity, which can clean the nozzle in real time or periodically to prevent impurities and deposits from clogging the nozzle orifice, ensuring that the nozzle remains unobstructed for a long time, while reducing the frequency of manual disassembly and cleaning.

[0036] Seventh, in the preferred implementation, this application controls the spraying distance between the spray nozzle and the micro-engine blade processing surface to 50-100mm, which ensures that the coating particles are uniformly deposited within a suitable flight distance, avoiding accumulation due to too close a distance or insufficient adhesion due to too far a distance; at the same time, limiting the nozzle diameter to the range of 80-300μm can achieve a reasonable balance between atomization effect and spraying precision, ensuring that the sprayed particles are fine and uniform, and improving the spraying coverage efficiency, thereby obtaining a coating with good density, strong adhesion and excellent surface quality.

[0037] Eighth, in the preferred implementation, this application integrates the fluid delivery module, temperature control module, ultrasonic vibration module and electromagnetic field generator into an overall operating unit. The tank of the temperature control module can be directly connected to an external lifting device, which facilitates the flexible lifting and position adjustment of the entire module.

[0038] Ninth, the method of the micro-engine blade temperature-controlled ultrasonic composite liquid gallium-assisted grinding device of this application, through the synergistic regulation of gas and liquid gallium metal and the unique phase design of icy gallium metal, achieves the formation of a uniform and stable three-phase distribution mixed medium under the combined action of ultrasound and electromagnetic field, which can enhance the wettability and dispersibility of liquid gallium on the blade surface; at the same time, ultrasonic cavitation, micro-jet and acoustic flow disturbance effectively break the oxide film and promote the formation of a dense pre-film layer, ensuring the uniformity and adhesion of the sprayed film layer; in the subsequent grinding process, the film layer can not only play a buffering and cooling role, but also work with the grinding wheel to achieve efficient and precise removal of the surface, thus taking into account temperature control, lubrication and processing quality, and improving the stability and surface quality of the micro-engine blade processing process. Attached Figure Description

[0039] Figure 1 This is a schematic diagram of the overall structure of the micro-engine blade temperature-controlled ultrasonic composite liquid gallium-assisted grinding device according to an embodiment of the present invention;

[0040] Figure 2 This is a schematic diagram of the structure of the ultrasonic vibration module according to an embodiment of the present invention;

[0041] Figure 3 This is a schematic diagram of the structure of an ultrasonic transducer assembly according to an embodiment of the present invention;

[0042] Figure 4 This is a schematic diagram of the current regulator and nozzle cleaning device according to an embodiment of the present invention;

[0043] Figure 5 This is a schematic diagram of the processing module in an unprocessed state according to an embodiment of the present invention;

[0044] Figure 6 This is a schematic diagram illustrating the processing state of the processing module in an embodiment of the present invention;

[0045] Figure 7 This is a flowchart of a method for a micro-engine blade temperature-controlled ultrasonic composite liquid gallium-assisted grinding device according to an embodiment of the present invention.

[0046] The components include: 1-Main controller; 2-Switch controller; 3-Current controller; 4-Fluid transport module; 40-Gas storage tank; 41-Gas drive pump; 42-First pressure regulating valve; 43-Liquid storage tank; 44-Second pressure regulating valve; 45-Air inlet pipe; 46-Liquid inlet pipe; 47-Stirring blade; 5-Temperature control module; 50-Microwave cavity; 51-Tank body; 52-Coolant pipe; 53-Coolant tank; 54-Coolant pump; 6-Machining module; 60-Thin-walled grinding wheel; 61-Grinding spindle; 62-Feed mechanism; 7-Ultrasonic vibration module; 70-Passive winding module; 80-Thin-walled grinding wheel; 90-Grinding spindle; 10-Current control module; 11-Switch controller; 12-Current control module; 13-Current control module; 14-Current control module; 15-Current control module; 16-Liquid inlet pipe; 17-Stirring blade; 18-Temperature control module; 19-Microwave cavity; 10-Tank body; 10-Coolant pipe; 11-Gas drive pump; 12-Coolant pump; 13-Coolant pump; 14-Coolant pump; 15-Coolant pump; 16-Coolant pump; 17-Coolant pump; 18-Coolant pump; 19-Coolant pump; 10-Coolant pump; 10-Coolant pump; 11-Coolant pump; 12-Coolant pump; 13-Coolant pump; 14-Coolant pump; 15-Coolant pump; 18-Coolant Filter screen; 71-Ultrasonic cavity; 72-Ultrasonic vibration module housing; 73-Blade guide wheel; 74-Ultrasonic transducer assembly; 740-Ultrasonic generator; 741-Ultrasonic frequency regulator; 742-Ultrasonic amplitude regulator; 743-Ultrasonic transducer; 744-Ultrasonic conduit; 75-Spray nozzle; 8-Electromagnetic field generator; 80-Current regulator; 81-Electromagnetic coil; 9-Spray nozzle cleaning device; 90-Liquid inlet; 91-Cleaning fluid drive pump; 92-Rotating arm; 93-Conduit; 94-Cleaning nozzle; A-Miniature engine blade. Detailed Implementation

[0047] To enable those skilled in the art to better understand the technical solutions of this application, the following will provide a more detailed description of this application in conjunction with the accompanying drawings and embodiments.

[0048] The directional terms such as above, below, left, right, front, and back used in this application are based on the positional relationships shown in the attached drawings. Different attached drawings may result in different positional relationships, therefore they should not be interpreted as limitations on the scope of protection.

[0049] In this application, the terms "installation," "connection," "interlocking," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, an integral connection, a mechanical connection, an electrical connection, or a connection that allows communication between components. They can also refer to a direct connection or an indirect connection through an intermediate medium. They can refer to the internal connection of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0050] This invention discloses a temperature-controlled ultrasonic composite liquid gallium-assisted grinding device and method for micro-engine blades.

[0051] Example

[0052] Refer to the instruction manual appendix Figure 1-3The micro-engine blade temperature-controlled ultrasonic composite liquid gallium-assisted grinding device includes a fluid delivery module 4, a temperature control module 5, a processing module 6, an ultrasonic vibration module 7, and an electromagnetic field generator 8. The temperature control module 5 is a temperature control unit, comprising a microwave cavity 50, a tank 51, and a cooling system. Both the microwave cavity 50 and the tank 51 are hollow cylindrical annular structures. The microwave cavity 50 is located in the central axial region of the tank 51, forming a nested layout. The microwave cavity 50 is used to heat the composite liquid gallium through an internal microwave radiation source, providing thermophysical protection for subsequent grinding. A closed annular cooling cavity is formed between the microwave cavity 50 and the tank 51, filled with a highly efficient thermally conductive coolant (such as ethylene glycol solution), achieving coordinated control of microwave heating and cooling temperature control. The inlet and outlet of the cooling system are connected to the side wall of the tank 51 via pipelines to control the coolant temperature within the annular cooling cavity.

[0053] The bottom of tank 51 is equipped with a composite liquid gallium outlet, which serves as the outlet channel for transporting liquid metal to downstream modules. An ultrasonic vibration module 7 is installed at the bottom of tank 51 and connected to its composite liquid gallium outlet channel. The ultrasonic vibration module 7 has an embedded high-frequency piezoelectric ultrasonic transducer that can output ultrasonic signals of specific frequency and intensity. This generates a periodic cavitation effect on the composite liquid gallium medium through ultrasound, forming numerous microbubbles. This enhances the fluidity and surface penetration of the liquid metal. Simultaneously, the cavitation effect disrupts the oxide film on the liquid metal surface, achieving efficient breakage and dispersion of solid phase aggregates in the fluid. This results in uniform film particles with a particle size distribution in the micrometer range, improving coating uniformity and adhesion. This facilitates the filling of liquid metal into microcracks and micro-gaps on the blade surface, achieving high-quality grinding-assisted coverage of complex curved surfaces.

[0054] The fluid transport module 4, a key system for the formation and transport of composite liquid gallium in this device, includes a gas storage tank 40, a liquid storage tank 43, an air inlet pipe 45, and a liquid inlet pipe 46. It aims to achieve precise control and dynamic mixing of the gas and liquid media, providing the ultrasonic vibration module 7 with a composite liquid metal that exhibits excellent flowability, suitable temperature, and processing capabilities. The gas storage tank 40 and liquid storage tank 43 are located outside the tank body 51 and are closed high-pressure containers. The gas storage tank 40 is filled with an inert gas (such as nitrogen N2 or argon Ar) or a reducing gas (such as hydrogen H2). The inert gas effectively inhibits the oxidation of the liquid metal and maintains the chemical stability of the mixture, while the reducing gas assists in removing the oxide film and improves the wettability and adhesion of the composite liquid to the blade crack surface. The storage tank 43 contains liquid metal matrix material, commonly liquid gallium (Ga) or liquid gallium alloy (such as Ga-In-Sn alloy), to provide the device with a highly lubricating, highly thermally conductive, and highly permeable metal-based fluid as the core processing medium for grinding cooling and surface repair.

[0055] One end of the air inlet pipe 45 is connected to the outlet of the gas storage tank 40, and the other end penetrates the side wall of the tank body 51, and is wrapped and fixed to the outer wall of the microwave cavity 50 and connected to the composite liquid gallium outlet at the bottom of the tank body 51. One end of the liquid inlet pipe 46 is connected to the outlet of the liquid storage tank 43, and the other end penetrates the side wall of the tank body 51, and is wrapped and fixed to the outer wall of the microwave cavity 50 and merged with the air inlet pipe 45. The air inlet pipe 45 and the liquid inlet pipe 46 are designed to be parallel near the composite liquid outlet, and turbulent mixing of the gas-liquid interface is achieved through a flow guide component or a porous mixing structure (such as an ejector or a turbulent mixing chamber), so as to mix with the metal gallium in the liquid inlet pipe 46 before the gas enters the ultrasonic vibration module 7 to form composite liquid gallium.

[0056] The ultrasonic vibration module 7 serves as the core for excitation and transport of the composite liquid gallium mixed medium. Its main function is to enhance the fluidity, permeability, and coating uniformity of the liquid metal through ultrasonic excitation and electromagnetic field coupling. The ultrasonic vibration module 7 includes an ultrasonic vibration module housing 72, an ultrasonic transducer 74 disposed within the housing 72, and a spray nozzle 75. The ultrasonic vibration module housing 72 is a closed structure designed to protect the internal precision components from external vibration, dust, and heat. The housing 72 possesses excellent vibration isolation and heat insulation properties, and its interior is equipped with shock-absorbing bases and thermally resistive materials.

[0057] The ultrasonic transducer assembly 74 includes an ultrasonic generator 740, an ultrasonic frequency modulator 741, an ultrasonic amplitude modulator 742, an ultrasonic transducer 743, and an ultrasonic conduit 744. The ultrasonic generator 740 is located at the top of the ultrasonic transducer assembly 74. The ultrasonic generator 740 has an internal cable interface and is electrically connected to the control system via a shielded cable. It is the signal source of the entire ultrasonic transducer assembly 74, responsible for outputting the original high-frequency electrical signal. The ultrasonic frequency modulator 741 and the ultrasonic amplitude modulator 742 are integrated with the ultrasonic generator 740 through embedded electrical connections, forming a functional module. The ultrasonic frequency modulator 741 is used to dynamically adjust the ultrasonic frequency to match different fluid characteristics and processing requirements. The ultrasonic amplitude modulator 742 is responsible for adjusting the amplitude of the signal, thereby controlling the intensity of the final mechanical vibration. By continuously adjusting and increasing or suppressing the ultrasonic force, it ensures that the cavitation intensity within the liquid metal is controllable. The ultrasonic transducer 743, installed at the bottom of the ultrasonic generator 740, is the core of the entire transducer system. It converts electrical energy into mechanical vibration (ultrasound). Its body is a solid piezoelectric structure, typically made of piezoelectric ceramic or composite crystal material. It converts the modulated electrical signal into mechanical vibration, which is then transmitted to the ultrasonic conduit 744. The ultrasonic conduit 744 has a slender tubular structure. Its upper end is precisely welded or threaded to the bottom plane of the ultrasonic transducer 743. Its inner cavity is a dedicated flow channel for composite liquid gallium metal, and its outer wall serves as the waveguide medium for ultrasound, participating in the waveguide and vibration transmission of ultrasound. This forms a synergistic excitation zone of tube wall resonance and fluid cavitation, ensuring that the ultrasonic energy is effectively applied to the composite liquid gallium medium. In the upper region of the ultrasonic conduit 744, a lateral liquid inlet is provided on the side wall near its upper end where it is connected to the ultrasonic transducer 743. This region is near the resonant section of the conduit, where the sound pressure gradient is the largest, making it easy to excite cavitation effect and surface disturbance. When the composite liquid metal enters the conduit, it is in the main excitation region of ultrasonic vibration, which is conducive to the immediate formation of cavitation effect.

[0058] The working principle of the ultrasonic transducer 74 can be divided into four stages: signal generation, parameter adjustment, energy conversion, and mechanical wave guidance. In the high-frequency signal generation stage, the control system sends an excitation command to the ultrasonic generator 740, which outputs a high-frequency AC signal at a set frequency as the source of vibration energy. In the parameter dynamic control stage, the ultrasonic frequency regulator 741 adjusts the frequency of the AC signal to achieve real-time adjustment of the ultrasonic resonance frequency (matching different liquid metal acoustic impedances), and the ultrasonic amplitude regulator 742 adjusts the amplitude to control the vibration intensity, ensuring that the cavitation intensity is within a stable range. Both work together to ensure that the output signal is in a system resonance state. In the energy conversion stage, the ultrasonic transducer 743 converts the electrical signal modulated by the ultrasonic frequency regulator 741 and the ultrasonic amplitude regulator 742 into axial high-frequency mechanical vibration. This mechanical vibration frequency is typically 20-60 kHz, which can generate cavitation bubbles in the liquid metal. During the mechanical waveguide stage, the ultrasonic conduit 744 carries the liquid metal medium and acts as an acoustic conductor. The vibration of the conduit induces periodic cavitation, micro-jet, and acoustic flow disturbance in the liquid metal inside the conduit, forming an effective microscale fluid excitation zone that promotes wetting, penetration, gap filling, and uniform adhesion.

[0059] One end of the spray nozzle 75 is directly connected to the bottom of the ultrasonic conduit 744, serving as the final output end for the liquid metal. The spray nozzle 75's spray outlet faces the upper surface of the micro-engine blade A to be machined, ensuring a vertical or moderately tilted spray angle. The spray nozzle 75 is made of corrosion-resistant, high-frequency-response alloy materials (such as titanium alloy or 316L stainless steel), and its internal channel structure can be a single-hole conical, concentric multi-hole, or coaxial gas-liquid dual-pass type. The nozzle structure design enables the liquid gallium to form a stable conical flow or columnar micro-beam, meeting the requirements of high-precision coating.

[0060] The nozzle diameter of the spray nozzle 75 is matched with the spraying mode. For example, when the spray nozzle 75 adopts a single-hole conical nozzle structure, the orifice diameter is configured to be 80–300 μm. This size range is suitable for forming a stable conical flow or columnar jet under a spray distance of 50–100 mm, constituting a controllable micro-beam. At the same time, it can obtain the required spray or jet diameter under a spray pressure of 0.1–2 MPa, achieving a film thickness of 20–50 μm and effectively reducing the probability of clogging. When the spray nozzle 75 adopts a multi-hole, concentric multi-hole, or coaxial gas-liquid dual-pass nozzle structure, the diameter of each hole is preferably 50–150 μm, and the number of holes is determined according to the requirements of jet intensity and coating uniformity. The equivalent flow cross-sectional area of ​​the entire nozzle group should be comparable to the cross-sectional area of ​​a single hole under the same flow conditions, further controlling the overall pressure loss and reducing the risk of single-hole clogging.

[0061] The minimum permissible orifice diameter of the 75 final-stage filter nozzle is 30μm±5μm, and the minimum nozzle diameter is set to be no less than 80μm. Ultrasonic backflushing and automatic cleaning ensure unobstructed flow even under conditions of particle size fluctuations and micro-agglomeration. The nozzle diameter significantly affects the spray pattern and coating accuracy: larger orifices tend to produce larger droplets or continuous jets, suitable for high-efficiency coverage but with lower precision; smaller orifices produce finer droplets, beneficial for high-resolution coating, and can be combined with more precise flow and pressure closed-loop control to suppress clogging and ensure spray stability.

[0062] The electromagnetic field generator 8 adopts a surrounding arrangement structure and is fixedly installed on the lower outer wall of the ultrasonic conduit 744, adjacent to the upper area of ​​the spray nozzle 75. The electromagnetic field generator 8 uses a multi-turn solenoid structure or a planar induction coil array, wound around the outer surface of the ultrasonic conduit 744. The electromagnetic field generator 8 can achieve a stable and efficient magnetic field output structure through housing slots, magnetic shielding shell encapsulation, or integrated molding technology. When an alternating current is applied to the electromagnetic field generator 8, the coil generates an alternating electromagnetic field. This magnetic field can induce eddy currents and Lorentz forces in the surrounding conductive fluid (composite liquid gallium). The eddy currents disturb the liquid metal flow field, disrupting its surface tension boundary layer and further enhancing its fluidity. The Lorentz force causes microscopic circulation flow within the fluid, improving the directionality and uniformity of the metal flow.

[0063] In this device, the fluid delivery module 4 introduces inert or reducing gases (such as argon or hydrogen) at room temperature (approximately 25°C) and liquid gallium metal (such as liquid gallium or low-melting-point Ga-In-Sn alloy) from the gas storage tank 40 and the liquid storage tank 43 through pipelines into the temperature control module 5. The liquid gallium metal is initially in a completely liquid state, with a melting point generally ranging from 10-30°C depending on the material (29.76°C for pure gallium, and as low as 10°C for Ga-In-Sn alloy). A closed annular cooling chamber is formed between the tank 51 and its internal microwave cavity 50 in the temperature control module. This chamber rapidly reduces the temperature of the gallium metal flowing through the pipeline to 10-15°C, below part of its melting point, through the circulation of highly efficient coolants such as ethylene glycol. This causes some components of the gallium metal to begin crystallizing, forming microscale solid grains, while the majority remains liquid. Subsequently, the microwave cavity 50 uses an internal microwave radiation source to locally heat the fluid pipes surrounding its outer wall in a non-contact manner, maintaining the local temperature slightly above the melting point (approximately 30-35°C). Thus, under the synergistic effect of overall cooling control and local heating regulation, the metal is achieved in a "partially solidified, partially liquid" state at the microscale, i.e., a slush-like state. This state, through the formation of a solid-liquid coexisting micro-slurry, allows the liquid metal to maintain a certain degree of fluidity while exhibiting higher surface adhesion, micro-gap filling properties, and spray directionality. This effectively avoids the problems of splashing or uneven adhesion that occur with completely liquid metal during spraying. Meanwhile, the gas remains in a gaseous state and does not participate in phase change. In the later section, it mixes with the metal in the parallel pipe area and enters the ultrasonic vibration module 7 through turbulent flow. The ultrasonic conduit 744 excites the composite liquid metal to generate cavitation and microfluidic disturbance through high-frequency mechanical vibration of 20-60kHz, making the slush metal slurry more uniform and stable. Meanwhile, the alternating electromagnetic field generated by the downstream electromagnetic field generator 8 excites eddy currents and Lorentz forces in the conductive fluid, further enhancing its fluidity, spray focusing and surface wettability. Finally, it acts on the surface of the micro-engine blade in a stable micro-beam manner through the spray nozzle 75, achieving precision grinding-assisted coverage of micro-cracks and complex curved surfaces.

[0064] In this embodiment, the fluid delivery module 4, temperature control module 5, ultrasonic vibration module 7, and electromagnetic field generator 8 constitute an integrated working unit. The temperature control module 5 is mechanically connected to an external lifting device via its tank 51, facilitating overall vertical movement. The processing module 6 is positioned on one side of the micro-engine blade A and is specifically used for precision grinding of the target surface of the micro-engine blade A using a grinding wheel. During processing, the external lifting device first drives the tank 51 downwards until a preset spraying distance (e.g., 50mm-100mm) is reached between the nozzle of the spray head 75 and the processing surface of the micro-engine blade A. Then, pre-prepared composite liquid gallium is uniformly sprayed onto the blade surface. After spraying, the external lifting device controls the tank 51 to move upwards, providing sufficient grinding space for the processing module 6. Next, the processing module 6 starts, controlling the grinding wheel to perform orderly grinding along the surface of the micro-engine blade A. The processing path and feed rate are adjusted according to set parameters to ensure processing accuracy and surface quality.

[0065] In this embodiment, the tank 51 adopts a multi-segment composite structure, consisting of a cylindrical cavity, a hemispherical shell, and a conical shell connected sequentially from top to bottom. The cylindrical cavity is the upper main cavity, used to house the microwave cavity 50, and its lower end is sealed to the hemispherical shell by a flange or welding. The top of the hemispherical shell is a flat plane, which connects to the bottom of the cylindrical cavity, with its spherical surface facing downwards. The bottom of the hemispherical shell is provided with a gas-liquid mixture outlet that communicates with the conical shell, and the gas-liquid mixture outlet is connected to the end of the liquid inlet pipe 46. The conical shell tapers downwards axially, with its cone angle pointing downwards, forming a conical discharge outlet structure.

[0066] The microwave cavity 50 has a cylindrical structure and is coaxially arranged inside the cylindrical cavity of the tank 51. Its diameter is preferably 60%-80% of the inner diameter of the cylindrical cavity to ensure that its circumferential clearance can accommodate fluid circulation and uniform heat transfer. The side wall of the tank 51 is provided with multiple pipe through-holes, including liquid inlet pipe through-holes, air inlet pipe through-holes, coolant inlet and outlet through-holes, pressure sensor through-holes, and microwave energy conduction interface through-holes. These pipe through-holes are arranged at different height positions of the tank 51 to ensure efficient and coordinated operation of the raw material inlet / outlet, temperature control medium circulation, parameter monitoring, and microwave heating functions.

[0067] The cooling system of the temperature control module 5 is used to control the heat exchange of the tank 51 and its internal reaction chamber, thereby achieving precise regulation of the medium temperature within the system. The cooling system includes coolant pipes 52, a coolant tank 53, and a coolant pump 54. The coolant pipes 52 include a first coolant pipe 52a, a second coolant pipe 52b, and a third coolant pipe 52c. The coolant tank 53 is a sealed liquid storage container used to store a predetermined volume of coolant, and its outlet is connected to the inlet of the coolant pump 54 via the first coolant pipe 52a. The outlet of the coolant pump 54 is connected to the inlet of the tank 51 via the second coolant pipe 52b, forming an inlet path. The tank 51 has an outlet, which returns the coolant to the coolant tank 53 via the third coolant pipe 52c, forming a closed coolant circulation loop. The coolant pipes 52 can be made of pressure-resistant and corrosion-resistant materials (such as fluororubber tubing or stainless steel corrugated pipes) to meet the safety requirements of operation in a microwave environment.

[0068] In this embodiment, the coolant tank 53 not only serves as a coolant storage device but also functions as a heat release unit. To improve cooling efficiency, the coolant tank 53 is equipped with an external forced heat dissipation structure. The tank body of the coolant tank 53 is made of a high thermal conductivity material (such as aluminum alloy or copper), and the outer wall of the tank is provided with heat dissipation fins to increase the surface area and enhance the heat exchange capacity with the surrounding air. The coolant stays in the tank for a relatively long time, and initial cooling can be achieved through natural convection, which is suitable for systems with low heat dissipation power. A fan module (air cooler) is mounted on the outer wall of the coolant tank 53 via a bracket. The fan forces air over the heat dissipation fins, increasing the heat exchange rate. This structure is suitable for applications with limited space and moderate system heat generation, and is simple in structure, low in cost, and easy to maintain. In addition, for high-power microwave heating systems, a plate or shell-and-tube heat exchanger can be installed between the coolant tank 53 and the external heat dissipation system to transfer the heat carried by the coolant to an independent chilled water system, and then achieve high-power heat dissipation through an external cooling tower or chiller unit, thereby maintaining the stability of the circulating coolant temperature. This method is suitable for continuous long-term operation or high heat load conditions.

[0069] In this embodiment, the coolant is preferably an aqueous solution of ethylene glycol or a perfluorinated liquid (such as FC-3283, HFE-7100, etc.). These cooling media possess excellent thermal conductivity, electrical insulation, and thermal stability, enabling safe operation in high electromagnetic field environments. During system operation, the coolant pump 54 starts, driving the coolant from the coolant tank 53 through the coolant pipe 52, sequentially flowing through the cooling channels or jacket structure of the tank body 51. After absorbing heat conducted from its surface and interior, the coolant flows back to the coolant tank 53, where it is cooled by natural heat dissipation or by a matching condenser before re-entering the circulation loop. The coolant continuously circulates in a closed loop, achieving continuous dynamic cooling of the tank body, preventing excessively high reaction temperatures from affecting the reaction rate or the stability of the microwave cavity, thereby ensuring the overall thermal field uniformity and process controllability of the system.

[0070] In this embodiment, to balance microwave shielding, reflectivity, and thermal conductivity, the shell of the microwave cavity 50 is preferably made of a high-conductivity metal material, such as nickel-plated copper or 316L stainless steel. Nickel-plated copper has excellent conductivity and high reflectivity, making it suitable for high-frequency microwaves. 316L stainless steel has strong corrosion resistance and good mechanical strength, making it suitable for environments requiring hygiene and pressure resistance. Preferably, the interior of the microwave cavity 50 shell can be locally plated with a silver or nickel layer to optimize reflectivity. The cavity wall thickness of the microwave cavity 50 is designed according to the microwave frequency (e.g., 2.45 GHz) and strength and pressure resistance standards, generally between 3-8 mm, to ensure mechanical strength and shielding performance.

[0071] The tank 51 also includes a microwave power supply system consisting of a magnetron, a waveguide, a transformer, and a power interface. The waveguide, magnetron, transformer, and power interface are encapsulated within a sealed housing to isolate them from coolant contact, preventing microwave leakage and electrical short circuits. This sealed housing is mounted on the outer wall of the microwave cavity 50 via a bracket made of a heat-insulating, high-temperature resistant composite material (such as alumina ceramic composite carbon felt), capable of withstanding high temperatures and electromagnetic interference in the working environment. The front end of the waveguide connects to the antenna radiation port built into the magnetron, and the rear end of the waveguide is coupled to the metal housing of the microwave cavity 50 through a connecting opening. Microwaves output from the antenna are transmitted via the waveguide, directly injecting microwave energy into the interior of the microwave cavity 50. The power interface extends through the outer wall of the tank 51 via a high- and low-temperature resistant sealed cable and connects to an external power source to power the transformer. The transformer converts alternating current into high-voltage direct current to power the magnetron for stable operation. The bottom region inside the microwave cavity 50 is equipped with materials for microwave absorption. These materials include: carbon materials (such as graphite blocks or carbon fiber felt) for efficient initial absorption; ceramic materials (such as silicon carbide and aluminum nitride) for high-temperature stability and dielectric loss; and polymer materials (such as engineering plastics containing polar groups) suitable for the low-temperature microwave absorption stage. This material forms the microwave initiation load and heat source core area, ensuring sufficient absorption medium during the initial heating stage of the microwave cavity 50, preventing microwave idling, and improving safety and heating uniformity.

[0072] Microwaves are emitted by a magnetron, transmitted through a waveguide, and injected into the microwave cavity 50. The bottom of the microwave cavity 50 is equipped with a microwave absorbing load made of carbon / ceramic / polymer. These materials convert microwave energy into heat energy. The microwave energy forms a standing wave field in the cavity, and the absorbing medium heats up rapidly in this field. Since the microwave cavity structure is a closed metal cavity, it does not directly absorb microwaves, but it absorbs the heat from the internal load through thermal conduction and thermal radiation. The heat generated by the load inside the microwave cavity is radially conducted to the outer wall along the thickness of the shell. The air inlet pipe 45 and the liquid inlet pipe 46 adopt a spiral winding structure and are evenly laid on the cylindrical outer wall of the microwave cavity 50 in an alternating manner. The air inlet pipe 45 and the liquid inlet pipe 46 are in direct contact with the outer wall of the microwave cavity 50 and obtain heat through metal contact heat conduction. Due to the spiral winding design, there is a large contact surface, which effectively improves the heat exchange and response speed per unit time. A stable heat transfer surface is formed during the temperature rise of the outer wall of the cavity, so that the gas flowing through the air inlet pipe 45 and the liquid metal inside the liquid inlet pipe 46 are heated.

[0073] In this implementation, the fluid delivery module 4 further includes a gas-driven pump 41, a first pressure regulating valve 42, a second pressure regulating valve 44, and a liquid metal-driven pump. The gas-driven pump 41 employs a high-precision metering pump, such as a plunger pump, diaphragm pump, or peristaltic pump, to achieve high-precision control of minute flow rates. The inlet of the gas-driven pump 41 is connected to a gas storage tank 40 to obtain high-purity inert gas (such as nitrogen, argon, etc.), and its outlet is connected to the first pressure regulating valve 42 via an inlet pipe 45. The gas-driven pump 41 is used to quantitatively extract and deliver gas to the temperature control module 5 to provide a gas source for subsequent gas-liquid phase mixing reactions. The first pressure regulating valve 42 is used to regulate the pipeline pressure after the pump outlet, preventing instantaneous pressure fluctuations from affecting the stability of the downstream reaction environment, and has a buffering and flow rate stabilizing function. The second pressure regulating valve 44 is located in the pipeline section between the inlet pipe 45, which exits the microwave cavity 50, and the liquid inlet pipe 46. It is used to individually regulate the pressure of the gas passing through the gas path, adapting to the pressure requirements of the gas-liquid mixing area, coordinating the pressure difference with the first regulating valve, achieving composite pressure segmented control, and improving the system's dynamic response capability. A liquid metal gallium drive pump is located on the liquid inlet pipe 46, between the outlet end of the storage tank 43 and the outside of the tank body 51. It is used to drive the liquid metal gallium to flow out of the storage tank 43. The liquid metal gallium drive pump is a magnetic pump or a ceramic micro pump made of high-temperature resistant and corrosion-resistant materials.

[0074] The fluid delivery module 4 also includes stirring blades 47 and a motor. The motor is located at the center of the bottom inner side of the hemispherical shell of the tank 51 through its housing. The output shaft of the motor extends downward from the central shaft position at the bottom of the hemispherical shell and is connected to the upper end of the stirring blades 47 via a high-temperature sealed bushing or a magnetic coupling device. The connection between the output shaft and the stirring blades 47 can be a tapered pin fastener or a quick-release bayonet type for easy maintenance and replacement. The stirring blades 47 are located on the outer side of the bottom of the hemispherical shell of the tank 51 and inside the tapered shell. The stirring blades 47 have a multi-bladed inclined blade structure with a certain lift angle to enhance shearing and circulation. Because the liquid metal gallium after being conditioned by tank 51 is in a slush-like state, it forms a mixture of microcrystals and small droplets with high viscosity. The metal microcrystals are spherical or needle-shaped and easily aggregate. After mixing with the gas, it forms a three-phase mixture similar to foamy slush or bubble-crystal-liquid film, which is very easy to stratify or clog. The stirring blades 47 create a strong shear zone and an axial vortex flow field, which has a de-agglomeration effect on the slush-like metal gallium and gas aggregation zone, so that the metal gallium microcrystals and bubbles are fully dispersed, forming a more uniform three-phase distribution system. This avoids large bubbles or microcrystal clusters from floating and aggregating, and maintains the system in a stable suspension state. In addition, the stirring in the area after the gas is mixed generates bubble shearing and rupture, forming more microbubbles and improving the dispersion of gas in the gallium liquid.

[0075] The gas-liquid mixture outlet at the bottom of the hemispherical shell of tank 51 is located at the bottom of the hemispherical shell in the middle of tank 51 (on one side of the motor output shaft) and is connected to the end of the liquid inlet pipe 46 via a conduit. The outlet direction of this gas-liquid mixture outlet has a certain cone angle, facing the rotation zone where the stirring blade 47 is located. The guide angle guides the gas-liquid mixture towards the center of the stirring blade 47, enhancing shearing and redispersion. The cone angle of the conduit outlet is 10°-45°, optimized according to the material viscosity and stirring radius. The cone angle structure changes the fluid entry direction, causing the gas-liquid mixture to not fall vertically, but to rush into the stirring zone in a tangential manner at an oblique flow velocity. The fluid is introduced from the outlet into the bottom area of ​​the stirring blade, where it is further dispersed and disturbed under the shearing action of the rotating blade. For icy metal materials containing bubbles, the oblique jet accelerates bubble breakage and dispersion, inhibiting buoyancy or agglomeration.

[0076] In the embodiments of this application, the air inlet pipe 45 and the liquid inlet pipe 46 are used to deliver gas and liquid into the tank 51, respectively, to form a uniform gas-liquid mixture. The merging structure of the air inlet pipe 45 and the liquid inlet pipe 46 adopts a T-type tee connector. The T-type tee connector is set on the section of the liquid inlet pipe 46 that extends out of the microwave cavity 50. The end of the liquid inlet pipe 46 is connected to the conduit at the gas-liquid mixture outlet of the tank 51 via the outlet of the T-type tee connector, and the other end of the T-type tee connector is connected to the end of the liquid inlet pipe 46. The mixed gas-liquid fluid enters the conical shell of the tank 51 through the integrated outlet conduit. Preferably, the T-type tee connector is provided with a flow guide cone or baffle to prevent backflow and promote uniform mixing.

[0077] In this implementation, the ultrasonic vibration module 7 further includes a filter 70 and a blade guide wheel 73. The ultrasonic vibration module housing 72 has a vertically penetrating ultrasonic cavity 71, which is cylindrical and has a partitioned structure to form multi-stage processing zones. The upper end of the ultrasonic cavity 71 is sealed to the conical shell at the bottom of the tank 51 via a flange or thread, ensuring a stable transition of the mixture flow. The ultrasonic cavity 71 receives the gas-liquid mixed metal particles after being sheared and dispersed by the stirring blades 47 within the conical shell. The filter 70 is located on the inner top of the ultrasonic cavity 71 and fixed to the inner wall of the cavity. The filter 70 traps agglomerates or large metal particles that have not been sufficiently sheared and dispersed by the stirring blades 47, preventing them from entering the lower part of the ultrasonic cavity 71 and affecting the rotational flow guidance of the blade guide wheel 73 and the vibration efficiency of the ultrasonic transducer assembly 74.

[0078] Furthermore, the filter 70 is made of corrosion-resistant and high-temperature-resistant metal materials, such as stainless steel (e.g., 316L), titanium alloy, or nickel-based alloy, to withstand the effects of metal particles, high temperatures, and corrosive gases in the gas-liquid mixed metal matrix. The mesh of the filter 70 is a uniformly distributed woven metal wire mesh or a laser-perforated metal plate structure, which facilitates precise control of the pore size. In this application, the diameter of the bubbles and metal matrix particle agglomerates in the slush state is 10-50 μm, and the pore size of the filter 70 is set to 30 μm ± 5 μm to filter agglomerates or insufficiently dispersed components with particle sizes exceeding the target size. Preferably, the top inner side of the ultrasonic cavity 71 is provided with a slot that extends through both sides of the ultrasonic vibration module housing 72. The slot is used to install the filter 70, which facilitates cleaning and replacement of the filter 70. Preferably, the top inner side of the ultrasonic cavity 71 is provided with multiple slots, and a stepped filter 70 is arranged in the slots from top to bottom. The mesh size of the stepped filter 70 decreases layer by layer. By filtering layer by layer, the filter 70 is prevented from clogging in a short time. The pore size of the filter 70 located at the bottom layer is 30μm±5m.

[0079] The blade guide wheel 73 is located in the central region of the ultrasonic cavity 71 and is used to rotate and guide the filtered gas-liquid mixed metal into the ultrasonic field below. Rotating shafts are located on both sides of the center of the blades of the blade guide wheel 73. These two rotating shafts are rotatably connected to the side wall of the ultrasonic cavity 71 via bearings. One rotating shaft extends out of the side wall of the ultrasonic cavity 71 and is connected to a miniature high-speed motor. This motor is connected to the motor output shaft via a coupling, and the motor control unit allows for speed adjustment, enabling dynamic control of the fluid distribution in the mixture. Preferably, the blades of the blade guide wheel 73 are distributed at an inclined angle, which enhances the flow guidance effect. The miniature high-speed motor drives the blade guide wheel 73 to rotate, inducing turbulence and guiding the filtered gas-liquid mixed metal tangentially into the ultrasonic action zone, thereby improving the ultrasonic transduction efficiency.

[0080] One end of the ultrasonic transducer 74 is located below the blade guide wheel 73 inside the ultrasonic cavity 71, and the other end extends out of the bottom of the ultrasonic cavity 71 and connects to the spray nozzle 75, forming an integrated ultrasonic spraying path. Since the upper sidewall of the ultrasonic conduit 744 has a lateral liquid inlet, this location is near the resonant section of the ultrasonic conduit, where the sound pressure gradient is maximum, facilitating cavitation. Therefore, a guide plate is installed at this lateral liquid inlet. This guide plate is used to receive the gas-liquid composite metal atom driven by the rotation of the blade guide wheel 73 and precisely guide it into the inner cavity of the ultrasonic conduit 744. This design ensures that the metal atom is in the main ultrasonic excitation region the moment it enters the ultrasonic conduit, enhancing cavitation and disturbance effects.

[0081] Because the ultrasonic generator 740, ultrasonic frequency modulator 741, ultrasonic amplitude modulator 742, and ultrasonic transducer 743 are located in a space in contact with liquid metal, electrical isolation and liquid-proof sealing designs are necessary. Specifically, the housings of the ultrasonic generator 740, ultrasonic frequency modulator 741, ultrasonic amplitude modulator 742, and ultrasonic transducer 743 are integrated modular enclosures, all made of high-strength corrosion-resistant alloy or PFA-coated metal. These integrated modular enclosures are fixed to one side within the ultrasonic cavity 71. The vibrator of the ultrasonic transducer 743 extends from the bottom of the integrated modular enclosure and connects to the top of the ultrasonic conduit 744. A flexible sealing cover is used between the vibrator and the bottom of the integrated modular enclosure. The bottom of the ultrasonic conduit 744 extends out from the bottom of the ultrasonic cavity 71 and connects to the spray nozzle 75.

[0082] Since the cable is led out from the top of the ultrasonic generator 740 and connected to the external control system through a dedicated high-frequency coaxial shielded cable, the cable outlet is equipped with a multi-level sealing protection structure. For example, the first layer is a cable through-hole sleeve + epoxy resin potting, the second layer is a waterproof bayonet + a temperature-resistant sealing ring, and the third layer is an electromagnetic shielding grounding cover installed at the external connector to prevent electromagnetic interference and corrosion.

[0083] As per the instruction manual Figure 4In this implementation, the electromagnetic coil 81 has a wound structure, surrounding and installed around the lower region of the ultrasonic conduit 744, and encapsulated in a high-temperature resistant insulating cover to prevent liquid metal corrosion and electromagnetic interference. A current regulator 80 is connected to one side or the tail end of the electromagnetic coil to precisely control the magnitude, direction, and frequency of the input current. By adjusting the input parameters through the current regulator 80, the intensity and form (alternating or direct current) of the electromagnetic field can be controlled, thereby regulating the distribution of the local magnetic field around the ultrasonic conduit 744. After energization, the electromagnetic coil 81 generates an axial or radial magnetic field in its encapsulated area. The magnetic field strength is proportional to the number of coil turns and the current; changing the current direction adjusts the magnetic field direction. This controllable magnetic field drives the liquid metal flow inside the ultrasonic conduit 744, achieving directional and velocity control of its coating layer, thereby precisely adjusting the coating thickness to ensure it remains stable between 20μm and 50μm, meeting the requirements of high-precision coating processes.

[0084] In this implementation, the micro-engine blade temperature-controlled ultrasonic composite liquid gallium-assisted grinding device also includes a nozzle cleaning device 9. The nozzle cleaning device 9 is fixedly mounted on the bottom of the ultrasonic cavity 71 via a bracket, ensuring automatic cleaning without interfering with the processing area. The bracket and the cavity are connected by high-strength, corrosion-resistant bolts, facilitating future maintenance and replacement. The bracket has a precision-machined inner hole, which is fitted and fixed to the outer wall of the ultrasonic conduit 744 passing through the bottom of the ultrasonic cavity 71 via a clearance fit, preventing structural loosening due to vibration during operation of the cleaning device.

[0085] The nozzle cleaning device 9 is mounted on the bottom of the ultrasonic cavity 71 via a bracket. The nozzle cleaning device 9 includes a liquid inlet 90, a cleaning fluid drive pump 91, a rotating arm 92, a conduit 93, a cleaning nozzle 94, and a motor. The motor is a miniature DC servo motor or a stepper motor, mounted on the bracket body via a fastening structure, and equipped with a liquid-proof encapsulation housing to ensure stable operation in high humidity or splash environments. One end of the rotating arm 92 is connected to the motor output shaft, enabling 360° directional rotation. The other end of the rotating arm 92 is connected to one end of the conduit 93, and the other end of the conduit 93 is fitted with the cleaning nozzle 94. The orientation of the cleaning nozzle 94 can be adjusted by driving the rotating arm 92 via the motor, ensuring the spray is accurately aligned with the spray nozzle 75.

[0086] The cleaning fluid drive pump 91 employs a miniature peristaltic pump or plunger pump, providing strong driving capability and suitability for high-viscosity or corrosive cleaning agents. The cleaning fluid drive pump 91 is mounted on the side wall of the rotating arm 92 and equipped with vibration damping pads to prevent operating noise and structural fatigue. The inlet 90 of the cleaning fluid drive pump 91 is connected to an external cleaning agent storage tank via a hose and is equipped with a check valve and filter. The outlet of the other end of the cleaning fluid drive pump 91 is connected to the inlet on the conduit 93 via a pipeline, forming a closed-loop liquid supply path to prevent air bubbles and pressure fluctuations from affecting the nozzle cleaning effect. After grinding, the control system issues a cleaning command, the drive pump starts, and the motor simultaneously rotates the rotating arm to adjust the nozzle angle. The nozzle position is automatically aligned with the spray nozzle 75, which can be assisted by an image recognition system (such as a CCD).

[0087] As per the instruction manual Figure 5-6 In this implementation, the machining module 6 includes a thin-walled grinding wheel 60, a grinding spindle 61, and a feed mechanism 62. The thin-walled grinding wheel 60 is preferably a nickel-based alloy special grinding wheel (generating a Ga2O3 / NiGa2O4 composite ceramic film). The thin-walled grinding wheel 60 is fixed to the front end of the grinding spindle 61 via end-face mounting and is used for contact grinding with the micro-engine blade A. The thin-walled grinding wheel 60 has a high-hardness ceramic or resin-bonded structure with a small thickness to accommodate the thin-walled and curved surface structure of the blade. The grinding spindle 61 is a hollow high-precision electric spindle or a direct-drive high-speed motor spindle, with one end connected to the thin-walled grinding wheel 60 and the other end mounted on the slide of the feed mechanism 62. The feed mechanism 62 has an overall slider-lead screw-slide rail structure, realizing the forward and backward feeding action of the grinding spindle 61 and the thin-walled grinding wheel 60, thereby controlling the contact position between the thin-walled grinding wheel 60 and the micro-engine blade A.

[0088] Furthermore, the feed mechanism 62 includes a grinding spindle drive unit and a grinding spindle moving unit. The grinding spindle drive unit includes a rotary motor, bearings, and a slide. The slide is an integral structural plate. The rotary motor is fixed to one side of the slide via its motor housing. Bearing holes are provided on the slide for mounting bearings. The grinding spindle 61 passes through the bearings, with one end connected to the output shaft of the motor via a coupling, and the other end fitted with a thin-walled grinding wheel 60. The grinding spindle moving unit includes a slider, guide rails, a ball screw, and a servo motor. Slider blocks are mounted on both sides of the slide, and the sliders are slidably connected to the guide rails, which are fixed to the worktable. The ball screw is located between the two guide rails, and a screw nut is fitted onto the ball screw, with one side of the screw nut fixed to the slide. Both ends of the ball screw are mounted in bearing housings with bearings, with one end extending out of the bearing housing and connected to the output shaft of the servo motor via a coupling. The servo motor is fixed to the worktable via its housing.

[0089] The rotary motor of the grinding spindle drive unit is turned on, driving the thin-walled grinding wheel 60 to rotate at high speed. At this time, the slide table remains in the initial safe position to prevent accidental contact with the micro-engine blade A. The servo motor is started, driving the ball screw to rotate. Since the screw nut and slider are both mounted on the slide table, the rotation of the ball screw causes the screw nut to move on the ball screw, while the slider moves along the guide rail. By setting the servo motor to rotate clockwise, the slide table is precisely fed along the guide rail towards blade A, controlling the movement of the thin-walled grinding wheel 60 to the machining position on the surface of the micro-engine blade A. Counterclockwise rotation of the thin-walled grinding wheel 60 is used to exit the machining position on the surface of the micro-engine blade A. In addition, depending on the complex shape and positioning method of the blade, multi-axis linkage (such as adjusting the direction of the grinding spindle movement unit via XYZ) can be used to perform composite surface machining. After machining is completed, the slide table retracts, and the grinding spindle 61 stops rotating.

[0090] In the implementation of this application, the micro-engine blade temperature-controlled ultrasonic composite liquid gallium-assisted grinding device also includes a control system, which comprises a main controller 1, a switch controller 2, and a current controller 3. The main controller 1 uniformly schedules the switch controller 2 and the current controller 3 to achieve the orderly and coordinated operation of subsystems such as fluid management, temperature control, grinding feed, and ultrasonic excitation.

[0091] Specifically, the main controller 1 is connected to both the switch controller 2 and the current controller 3, outputting control commands to them to achieve process linkage. The main controller 1 uses a PLC, industrial-grade embedded controller, or industrial PC to provide control logic operations, sequential control, data acquisition, and task management. Communication methods include industrial bus protocols such as RS-485, CAN, Modbus, or EtherCAT. The switch controller 2 connects to the fluid delivery module 4, temperature control module 5, processing module 6, and ultrasonic vibration module 7 for starting and stopping. The switch controller 2 uses a relay array module or a multi-channel switch module. It receives commands from the main controller 1 to achieve timed on / off switching. The current controller 3 connects to the electromagnetic field generator, ultrasonic transducer, related drive pumps, related motors, and related sensors for power supply. The current controller 3 uses a PWM power supply module, a constant current / constant voltage controller, or a dedicated current amplification module.

[0092] This application discloses a temperature-controlled ultrasonic composite liquid gallium-assisted grinding device for micro-engine blades. Through a temperature control module, it employs a synergistic temperature control system of "internal microwave local heating and external loop cooling." Microwaves rapidly and controllably heat the gas / liquid pipelines wrapped around the outer wall of the cavity, while the annular cooling cavity continuously removes heat with a highly efficient coolant such as ethylene glycol, forming a stable thermal field. The liquid gallium is cooled overall at 10-15°C to form partially solidified microcrystals, and then locally heated to approximately 30-35°C in the microwave region, resulting in a solid-liquid composite liquid gallium that maintains fluidity while improving adhesion and orientation. The composite liquid gallium provides efficient heat conduction and exchange in the spraying / grinding contact area, suppressing grinding temperature rise and heat-affected layer thickness, reducing the risk of thermal cracking, tempering softening, and deformation. This solves the problems of high frictional heat in traditional grinding wheel grinding, leading to increased blade surface temperature, thermal damage, microstructural changes, deformation, and decreased precision and lifespan.

[0093] Leveraging the excellent wetting / filling capabilities of composite liquid gallium, it penetrates microcracks and microslits, providing both lubrication and cooling during grinding. Using the ultrasonic transducer and ultrasonic conduit of the ultrasonic vibration module, ultrasonic energy is coupled to the fluid, generating cavitation, microjets, and acoustic flow to continuously disrupt the film and reduce interfacial shear. By limiting the nozzle orifice diameter, spray pressure, and spray distance of the spray nozzle 75, stable microbeams and controllable film thickness of 20–50 μm are achieved. This results in a decrease in the coefficient of friction and cutting force, sharper and more stable abrasive cutting, reduced surface residual grooves and tearing, lower Ra, and improved machining quality. It solves the problem of insufficient traditional cooling and lubrication, making it difficult to achieve both high precision and low roughness on complex curved surfaces.

[0094] An electromagnetic field generator 8, located upstream of the nozzle, induces eddies and Lorentz forces in the conductive fluid, disrupting the surface tension boundary layer and achieving directional traction and homogenization of the flow field. Stirring blades and a multi-stage filter (30μm±5μm) are used to shear and disaggregate, suppressing agglomeration and stratification. Stepwise filtration prevents large particles from clogging the flow, ensuring a fine and uniform spray. This achieves highly uniform coverage and effective wetting of narrow / twisted / gap areas such as tenons, eliminating "tears / exposed areas / accumulation" phenomena, improving the processing consistency of complex curved surfaces, and solving the problems of high fluidity, difficult surface tension control, and inability to uniformly cover complex areas in existing technologies using liquid metals.

[0095] By utilizing the viscosity of the solid-liquid coexistence of the icy metal slurry, surface adhesion, anti-splattering properties, and directionality are improved, resulting in more stable jet convergence. The ultrasonic vibration module 7 continuously disrupts the oxide film on the substrate surface, enhancing wetting and adhesion. The Lorentz force driven by the electromagnetic field generator 8 creates localized micro-circulation and axially oriented flow, suppressing spray dispersion and improving film density. This results in a dense, strongly adhered coating with controllable thickness (20–50 μm), stable coverage, and reliable subsequent grinding assistance, solving the problems of poor coating adhesion, easy splattering, and insufficient coverage stability in existing technologies.

[0096] By utilizing the interaction between a nickel-based alloy grinding wheel and liquid gallium, a Ga2O3 / NiGa2O4 composite ceramic film can be generated under working conditions, improving the abrasive-workpiece interface behavior. This is because liquid gallium or gallium alloys readily react with oxygen in the air under high temperature and high friction environments to form Ga2O3 (gallium oxide). Gallium oxide is a chemically stable ceramic phase with high hardness, a high melting point (>1700℃), and can act as a protective / lubricating film at the grinding interface. Under the influence of frictional heat and liquid gallium, the nickel-based alloy in the nickel-based alloy grinding wheel may undergo interdiffusion and solid-phase reactions on its surface. In the presence of oxygen, nickel, oxygen, and gallium can form a spinel-type composite oxide, NiGa2O4, which exhibits good thermal stability and strong ceramic bonding at high temperatures. Ga2O3 and NiGa2O4 synergistically form a continuous film layer, preventing further chip adhesion and direct metal-to-abrasive contact. This film provides a high-temperature resistant and low-friction interface protection layer, while also enhancing the chemical stability between the grinding wheel abrasive grains and the workpiece, avoiding direct metal-to-metal contact, reducing the probability of burns / brittle fractures, and solving the problems of rapid wear and high risk of chip / burns when grinding nickel-based / high-temperature alloys with traditional grinding wheels.

[0097] By utilizing a multi-stage filtration and nozzle cleaning device 9, nozzle clogging and failure rates are reduced, the stability and maintainability of long-term continuous processing are improved, and the problem of easy clogging of micro-spray holes is solved.

[0098] In summary, the micro-engine blade temperature-controlled ultrasonic composite liquid gallium-assisted grinding device of the present invention realizes three-field coupling coating and lubrication cooling of "sand ice state composite liquid gallium" (solid-liquid coexistence) + ultrasonic cavitation + electromagnetic orientation. It implements a dual-channel temperature control structure of microwave local heating and loop cooling, and realizes the process of lateral liquid inlet of conduit resonant section, coil near nozzle arrangement, multi-stage filtration / stirring and debulking, and replaceable micro nozzle. It reduces grinding temperature rise and friction, suppresses thermal damage and burns, improves wetting and film formation quality, solves the problem of uneven coating and poor penetration in complex parts, reduces surface roughness, improves processing accuracy, surface integrity and fatigue life, and meets the manufacturing requirements of micro-engine blades for high performance and high reliability.

[0099] As per the instruction manual Figure 7 This invention also describes a method for a temperature-controlled ultrasonic composite liquid gallium-assisted grinding device for micro-engine blades. This method integrates temperature control and ultrasonic vibration technology, using liquid gallium as the medium for grinding micro-engine blades, improving coating uniformity and processing efficiency, and providing an innovative solution for the efficient and precise forming of complex materials. The method includes:

[0100] Step 1: Using the fluid transport module, gas and liquid gallium are introduced from the gas tank and liquid tank respectively. The gas and liquid gallium are transported to the temperature control module through the gas inlet pipe and liquid inlet pipe respectively, forming independent gas phase flow and liquid phase flow respectively.

[0101] The purpose of step 1 is to introduce gaseous and liquid gallium metal from the gas storage tank and liquid storage tank respectively through the fluid transport module, and transport them to the temperature control module through independent gas inlet pipe and liquid inlet pipe to form independent gas phase flow and liquid phase flow, so as to ensure the stability and controllability of the subsequent mixing process and provide a physical separation basis for the directional processing of different media.

[0102] Specifically, the liquid gallium is heated to 40-200℃ via a microwave cavity and a magnetron 8 at a rate of 50℃ / min, while the cooling temperature fluctuation is controlled within ±0.1℃.

[0103] By adjusting the phase change thermal buffer layer (thickness 0.2-0.5 mm) using a PID algorithm, the viscosity of liquid gallium was reduced from 1.2 Pa·s to 0.3 Pa·s, and the coefficient of friction was reduced from 0.6 to 0.15.

[0104] Step 2: Liquid gallium metal is cooled to below its partial melting point by a cooling system in a temperature control module, causing some components to precipitate microcrystals and form a slush-like gallium metal containing solid microcrystals and liquid metal. The slush-like gallium metal is then heated to a preset temperature slightly above its melting point by a non-contact heating method set in a microwave cavity to achieve local melting and maintain the overall slush-like state.

[0105] The purpose of step 2 is to induce microcrystal precipitation to form a sand-ice state of gallium by cooling liquid gallium metal to below a certain melting point. At the same time, non-contact microwave local heating is used to make some areas slightly above the melting point, so as to achieve local melting while maintaining the overall sand-ice structure. The aim is to enhance the structural stability of the liquid metal and improve its responsiveness to subsequent disturbances and processing adaptability.

[0106] Specifically, microwave heating and liquid nitrogen cooling are combined to create a partially molten state, while thermal buffering maintains the slush-like state, ensuring viscosity and crystallization control. The temperature control of the partially molten state is dynamically managed by a PID algorithm.

[0107] Step 3: The slush-like metal and gas are mixed at the ends of the liquid inlet pipe and the gas inlet pipe respectively to form a uniform gas-liquid composite mixture. This mixture is then introduced into the stirring area at the bottom of the temperature control module, where it is dispersed by high-speed shearing and rotation with the help of stirring blades to form a stable three-phase distribution mixed medium.

[0108] The purpose of step 3 is to allow the slush-like liquid metal and gas to undergo turbulent mixing at the parallel pipe structure before entering the stirring zone. Through high-speed shearing and rotational dispersion, the agglomerated microcrystals are further broken up, the bubbles are refined, and the three-phase homogeneous mixing is enhanced. The aim is to construct a stable, uniform composite mixing system suitable for ultrasonic treatment.

[0109] Specifically, the injection pump has an accuracy of 0.01 ml / min, a spray pressure of 0.1-2 MPa, an angle of 30-90°, a film thickness deviation of <5%, and an evaporation rate of <0.1 mg / s. A bellows compensator is used to control thermal expansion and contraction within ±0.5 mm.

[0110] Step 4: The stirred gas-liquid composite mixture flows into the ultrasonic vibration module, and the undispersed agglomerated particles and large bubbles are intercepted and separated by the filter structure set on the inner side of the top of the ultrasonic cavity. The filtered mixed fluid is guided by the blade guide wheel assembly to rotate downward in the tangential direction to the ultrasonic excitation area.

[0111] The purpose of step 4 is to trap large particles and bubbles that have not been fully sheared by using a filter structure set at the top of the ultrasonic cavity, and to guide the mixed fluid into the ultrasonic excitation zone along the tangential direction with the help of the blade guide wheel assembly. This aims to optimize the initial state of the fluid in the subsequent ultrasonic action area and improve the efficiency and uniformity of ultrasonic processing.

[0112] Step 5: After the mixed fluid enters the ultrasonic transducer, it is subjected to high-frequency ultrasonic excitation at a set frequency and amplitude to generate dense cavitation bubbles, microjets and acoustic flow disturbances, so as to destroy the oxide film structure on the surface of the mixed liquid and the solid phase aggregates in the fluid, so as to disperse them into finer micron film particles and form a uniform and dense pre-film layer.

[0113] The purpose of step 5 is to generate cavitation bubbles, microjets, and acoustic disturbances in the mixture through high-frequency ultrasonic excitation, effectively breaking the oxide film structure on the surface of the liquid metal, thereby forming a uniform and dense pre-metal film layer on the surface to be processed, with the aim of improving the bonding strength and surface quality between the film layer and the substrate.

[0114] Specifically, in step 5, the high-frequency ultrasound is 20-100 kHz, the cavitation microjets velocity is >100 m / s, the impact pressure is 50-200 MPa, and the time is 10-100 μs. The mechanical amplitude is 5-15 μm. The oxide film breakage rate is >95%, and the contact angle decreases from 90° to <30°. The cavitation bubble density is monitored in real time (100-1000 bubbles / mm). 2 The ultrasonic frequency and flow rate are matched by feedback from a piezoelectric sensor.

[0115] Step 6: An electromagnetic field generator is installed on the outer wall of the ultrasonic catheter. The alternating magnetic field is used to excite eddies and Lorentz force fields in the conductive liquid to control the internal flow circulation and direction of the mixed liquid metal.

[0116] The purpose of step 6 is to use an electromagnetic field generator installed on the outer wall of the ultrasonic conduit to generate an alternating magnetic field, induce eddies and Lorentz force fields inside the conductive liquid, and achieve flow path control and internal circulation optimization of the liquid metal. The aim is to further enhance the mixing uniformity and control the fluid stability and directionality during the spraying process.

[0117] Specifically, in step 6, the alternating magnetic field strength is 0.1-1T, and the frequency range is 10-100Hz. Liquid gallium molecules align in an orderly manner along the magnetic field direction, increasing the film density by 20-40%.

[0118] Step 7: The composite liquid metal is sprayed onto the surface of the micro-engine blade in the form of a micro-beam through a spray nozzle located at the bottom of the ultrasonic conduit. After the film is formed, the temperature control module is moved upward by an external lifting device, and the grinding wheel system in the processing module is started to perform precision grinding on the sprayed area.

[0119] The purpose of step 7 is to achieve high-quality deposition of the film and subsequent surface finishing, thereby improving the overall processing accuracy and film functionality.

[0120] Specifically, in step 7, the grinding tool is a nickel-based alloy grinding wheel with a thickness of 0.5-2 mm and a diamond grit size of 200-800 mesh. A Ga2O3 / NiGa2O4 ceramic film with a thickness of 2-5 μm is formed on the surface of the grinding wheel. The grinding wheel is adjusted using 6 sets of symmetrical adjustment components (coarse adjustment M3: 0-2 mm; fine adjustment M2: ±5 μm).

[0121] The spindle speed is 10,000-50,000 r / min, and the feed rate is 0.01-0.5 mm / s. The grinding depth is 80-200 nm, and the grinding force fluctuation is controlled within ±5 N. The groove depth of the grinding groove structure is 0.1-0.3 mm, the groove width is 0.05-0.1 mm, and the groove spacing is 0.2-0.5 mm.

[0122] The micro-engine blade temperature-controlled ultrasonic composite liquid gallium-assisted grinding device and method of this invention, after a multi-stage processing flow including cooling, shearing, ultrasonic crushing, and turbulent redispersion, microcrystalline metal particles are ultimately formed into a "bead-like microcrystalline / fine droplet composite". This composite is composed of solid microcrystalline nuclei encapsulating or encasing microscale liquid films. The overall particle morphology is mainly spherical or near-spherical, with a small number of particles appearing as short needles or irregular flakes. This particle morphology can effectively reduce surface tension, improve wettability to the substrate surface, and enhance the ability to fill microcracks in the blade. The micro-engine blade temperature-controlled ultrasonic composite liquid gallium-assisted grinding device and method of this invention addresses the problems of insufficient coating and poor penetration in existing liquid metal-assisted grinding by integrating an intelligent temperature control system, an ultrasonic vibration module, and an electromagnetic field flow control system to achieve efficient coating and penetration of liquid gallium during the grinding process. This device can precisely control the temperature of liquid gallium, ensuring that it maintains excellent fluidity in the grinding area. Combined with ultrasonic vibration, it further improves the ability to fill the blade surface and microcracks. Furthermore, it uses electromagnetic fields to precisely guide the flow direction and distribution, ensuring coating uniformity. This improves the precision and surface quality of the grinding process, effectively extending the blade's service life. It has significant practical value and promising prospects for engineering promotion.

[0123] The above descriptions are merely embodiments of this application, and common knowledge regarding specific structures and characteristics in the solutions is not described in detail here. It will be apparent to those skilled in the art that this application is not limited to the details of the above exemplary embodiments, and that this application can be implemented in other specific forms without departing from the spirit or essential characteristics of this application. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of this application is defined by the appended claims rather than the foregoing description. Therefore, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this application. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A temperature-controlled ultrasonic composite liquid gallium-assisted grinding device for micro-engine blades, characterized in that, It includes a fluid transport module (4), a temperature control module (5), a processing module (6), an ultrasonic vibration module (7), and an electromagnetic field generator (8); the temperature control module (5) includes a microwave cavity (50), a tank (51), and a cooling system. The microwave cavity (50) and the tank (51) are both hollow cylindrical annular structures. The microwave cavity (50) is embedded inside the tank (51), forming a closed annular cooling cavity between them. The inlet and outlet of the cooling system are connected to the cooling cavity through the side wall of the tank (51), respectively. The bottom of the tank (51) is provided with a composite liquid gallium outlet. The fluid transport module (4) includes a gas storage tank (40), a liquid storage tank (43), an air inlet pipe (45), and a liquid inlet pipe (46). The gas storage tank (40) and the liquid storage tank (43) are both located outside the tank body (51). The gas storage tank (40) is filled with inert gas, and the liquid storage tank (43) contains liquid gallium. One end of the air inlet pipe (45) is connected to the gas outlet of the gas storage tank (40), and the other end passes through the side wall of the tank body (51) and wraps around the outer wall of the microwave cavity (50) before connecting to the composite liquid gallium outlet at the bottom of the tank body (51). One end of the liquid inlet pipe (46) is connected to the liquid outlet of the liquid storage tank (43), and the other end passes through the side wall of the tank body (51) and wraps around the outer wall of the microwave cavity (50) before connecting to the lower end of the air inlet pipe (45). The ultrasonic vibration module (7) includes an ultrasonic vibration module housing (72), an ultrasonic transducer assembly (74), and a spray nozzle (75). The ultrasonic vibration module housing (72) is vertically continuous, and its top is connected to the composite liquid gallium outlet channel of the tank (51). One end of the ultrasonic transducer assembly (74) is located inside the ultrasonic cavity (71), and the other end extends out of the bottom of the ultrasonic cavity (71). The ultrasonic transducer assembly (74) includes an ultrasonic generator (740), an ultrasonic frequency modulator (741), an ultrasonic amplitude modulator (742), an ultrasonic transducer (743), and an ultrasonic generator (745). An ultrasonic conduit (744) is provided, wherein an ultrasonic generator (740) is located at the upper end of the ultrasonic transducer assembly (74), an ultrasonic frequency modulator (741) and an ultrasonic amplitude modulator (742) are integrated with the ultrasonic generator (740) through a module-embedded electrical connection, an ultrasonic transducer (743) is installed at the bottom of the ultrasonic generator (740), the upper end of the ultrasonic conduit (744) is connected to the ultrasonic transducer (743), the lower end is connected to the spray nozzle (75), and a lateral liquid inlet is provided on the side wall of the upper region of the ultrasonic conduit (744). The electromagnetic field generator (8) adopts a surround structure and is fixedly installed on the lower outer wall of the ultrasonic conduit (744) and adjacent to the spray nozzle (75); The micro engine blade to be processed is disposed below the spray nozzle (75), and the micro engine blade is fixed on the processing module (6). The processing module (6) includes a thin-walled grinding wheel (60) made of nickel-based alloy material.

2. The micro-engine blade temperature-controlled ultrasonic composite liquid gallium-assisted grinding device according to claim 1, characterized in that, The temperature-controlled tank (51) adopts a multi-segment composite structure, consisting of a cylindrical cavity, a hemispherical shell, and a conical shell connected sequentially from top to bottom; wherein, the cylindrical cavity is the upper main cavity, used to accommodate the microwave cavity (50), and its lower end is sealed to the hemispherical shell; the top of the hemispherical shell is connected to the bottom of the cylindrical cavity, and its spherical surface is set downward; the bottom of the hemispherical shell is provided with a gas-liquid mixture outlet communicating with the conical shell, and the gas-liquid mixture outlet is connected to the end of the liquid inlet pipe (46); the conical shell tapers downward along the axial direction, and its cone angle is downward, forming a conical outlet structure.

3. The micro-engine blade temperature-controlled ultrasonic composite liquid gallium-assisted grinding device according to claim 2, characterized in that, The fluid delivery module (4) includes a stirring blade (47) and a motor. The motor is located at the center of the bottom inner side of the hemispherical shell of the temperature control tank (51) through its housing. The output shaft of the motor passes downward from the central axis position at the bottom of the hemispherical shell and is connected to the upper end of the stirring blade (47). The stirring blade (47) is located on the outer side of the bottom of the hemispherical shell of the temperature control tank (51) and inside the conical shell of the temperature control tank (51).

4. The micro-engine blade temperature-controlled ultrasonic composite liquid gallium-assisted grinding device according to claim 2, characterized in that, The ultrasonic vibration module (7) includes a filter screen (70) and a blade guide wheel (73); the ultrasonic vibration module housing (72) is provided with an ultrasonic cavity (71) that runs vertically through it, and the ultrasonic cavity (71) is a cylindrical cavity; the filter screen (70) is disposed on the inner side of the top of the ultrasonic cavity (71) and fixed to the inner wall of the cavity; the blade guide wheel (73) is disposed in the middle region of the ultrasonic cavity (71); the ultrasonic transducer assembly (74) is located below the blade guide wheel (73).

5. The micro-engine blade temperature-controlled ultrasonic composite liquid gallium-assisted grinding device according to claim 1, characterized in that, The electromagnetic field generator (8) includes a current regulator (80) and an electromagnetic coil (81), the electromagnetic coil (81) being mounted around the periphery of the lower end region of the ultrasonic conduit (744), and the current regulator (80) being connected to one side of the electromagnetic coil (81).

6. The micro-engine blade temperature-controlled ultrasonic composite liquid gallium-assisted grinding device according to claim 4, characterized in that, It also includes a nozzle cleaning device (9), which is installed at the bottom of the ultrasonic cavity (71).

7. The micro-engine blade temperature-controlled ultrasonic composite liquid gallium-assisted grinding device according to claim 1, characterized in that, The spraying distance between the nozzle of the spraying head (75) and the processed surface of the micro engine blade is 50-100mm.

8. The micro-engine blade temperature-controlled ultrasonic composite liquid gallium-assisted grinding device according to claim 1, characterized in that, The fluid delivery module (4), temperature control module (5), ultrasonic vibration module (7) and electromagnetic field generator (8) constitute an integrated operating unit, wherein the temperature control tank (51) of the temperature control module (5) is used to connect to an external lifting device.

9. The micro-engine blade temperature-controlled ultrasonic composite liquid gallium-assisted grinding device according to claim 1, characterized in that, The nozzle diameter of the spray nozzle (75) is 80-300μm.

10. A method for a micro-engine blade temperature-controlled ultrasonic composite liquid gallium-assisted grinding device as described in any one of claims 1-9, characterized in that the method... include: Step 1: Using the fluid transport module, gaseous and liquid gallium metal are introduced from the gas tank and liquid tank respectively. The gaseous and liquid gallium metal are transported to the temperature control module through the gas inlet pipe and liquid inlet pipe respectively, forming independent gas phase flow and liquid phase flow respectively. Step 2: Liquid gallium metal is cooled to below its partial melting point by a cooling system in a temperature control module, causing some components to precipitate microcrystals and form a slush-like gallium metal containing solid microcrystals and liquid metal. The slush-like gallium metal is then heated to a preset temperature slightly above its melting point by a non-contact heating method set in a microwave cavity to achieve local melting and maintain the overall slush-like state. Step 3: The slush-like metal and gas are mixed at the ends of the liquid inlet pipe and the gas inlet pipe respectively to form a uniform gas-liquid composite mixture, which is then introduced into the stirring area at the bottom of the temperature control module. With the help of stirring blades, it is subjected to high-speed shearing and rotational dispersion to form a stable three-phase distribution mixed medium. Step 4: The stirred gas-liquid composite mixture flows into the ultrasonic vibration module, and the undispersed agglomerated particles and large bubbles are intercepted and separated by the filter screen structure set on the inner side of the top of the ultrasonic cavity. The filtered mixed fluid is guided by the blade guide wheel assembly to rotate downward along the tangential direction to the ultrasonic excitation area. Step 5: After the mixed fluid enters the ultrasonic transducer, it is subjected to high-frequency ultrasonic excitation at a set frequency and amplitude to generate dense cavitation bubbles, microjets and acoustic flow disturbances, so as to destroy the oxide film structure on the surface of the mixed liquid and the solid phase aggregates in the fluid, so as to disperse them into finer micron film particles and form a uniform and dense pre-film layer. Step 6: An electromagnetic field generator is installed on the outer wall of the ultrasonic catheter. The alternating magnetic field is used to excite eddies and Lorentz force fields in the conductive liquid to control the internal flow circulation and direction of the mixed liquid metal. Step 7: The composite liquid metal is sprayed onto the surface of the micro-engine blade in the form of a micro-beam through a spray nozzle located at the bottom of the ultrasonic conduit. After the film is formed, the temperature control module is moved upward by an external lifting device, and the grinding wheel system in the processing module is started to perform precision grinding on the sprayed area.

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