In-situ composite coating preparation device based on multi-field coupling and atmosphere regulation and control

Abstract

The invention discloses an in-situ composite coating preparation device based on multi-field coupling and atmosphere regulation and control. The in-situ composite coating preparation device aims at solving the problems that raw material powder is prone to agglomeration and moisture absorption in the spraying process, and the spraying quality is affected. A first powder outlet of each powder storage device in the in-situ composite coating preparation device communicates with a particle bombardment emission gun head through a first powder conveying pipeline, and a second powder outlet of each powder storage device communicates with a feeding port of a super thermal coupling pretreatment cabin through a second powder conveying pipeline; the heater and the plurality of high-frequency ultrasonic transducers are arranged on the superthermal coupling pretreatment cabin, and a discharge port of the superthermal coupling pretreatment cabin is connected with the powder deposition emission gun head through a powder conveying pipe. The problems of powder agglomeration and moisture absorption are solved through the thermal-ultrasonic coupling effect of the super-thermal coupling pretreatment cabin, the deposition threshold is lowered, the stable deposition environment is guaranteed by means of the gas phase environment precise conveying unit, and finally the composite coating high in compactness and binding force is obtained.

Description

Technical Field

[0001] This invention belongs to the field of materials surface engineering and additive manufacturing technology, and specifically relates to an in-situ composite coating preparation device with multi-field synergistic control. Background Technology

[0002] Spray coating technology utilizes high-pressure gas to accelerate solid powder particles, causing them to impact the substrate surface and resulting in severe plastic deformation, forming a modified layer or depositing a coating on its surface. However, existing technologies are limited by the agglomeration and hygroscopic tendency of powders, easily leading to unstable powder feeding, pipeline blockage, and problems such as poor coating density and insufficient adhesion. Furthermore, for high-strength, high-melting-point metal or alloy powders, the critical deposition rate is very high, requiring extremely high gas parameters, placing stringent demands on equipment, and resulting in low deposition efficiency. For workpieces with complex shapes, a fixed spraying angle can produce a "masking effect," leading to unevenness in the modified layer or coating.

[0003] To address these issues, existing technologies typically employ a single external field approach. For example, an ultrasonic field can disrupt powder agglomeration and improve flowability through high-frequency vibration and cavitation effects; a thermal field can preheat the powder delivery gas, reducing the critical deposition rate and removing some surface-adsorbed water. However, thermal fields suffer from low gas-solid heat transfer efficiency and are ineffective at resolving deep agglomeration; while ultrasonic fields can disperse powder, they cannot effectively lower the deposition threshold. Therefore, the improvement effect of a single external field is limited and cannot fundamentally optimize powder state and coating quality. Summary of the Invention

[0004] The purpose of this invention is to solve the problems of easy agglomeration and moisture absorption of raw material powder in the spraying process, which affect the spraying quality, and to provide a surface strengthening device that can significantly improve the state of raw material powder, improve coating quality, and achieve uniform surface modification or deposition of complex workpieces.

[0005] The present invention provides an in-situ composite coating preparation device based on multi-field coupling and atmosphere control, comprising an air compressor, a multi-component powder storage module, an ultra-thermal coupling pretreatment chamber, a sealed experimental chamber, a vacuum system, and a gas phase environment precision transport unit. The multi-component powder storage module comprises multiple powder storage devices. The air nozzle of the air compressor is connected in parallel to each powder storage device through a gas delivery pipeline. The first powder outlet of each powder storage device is connected to the particle bombardment firing head through a first powder delivery pipeline. The second powder outlet of each powder storage device is connected to the feed port of the ultra-thermal coupling pretreatment chamber through a second powder delivery pipeline.

[0006] The aforementioned ultra-thermal coupling pretreatment chamber includes an inlet, an outlet, a heater, and multiple high-frequency ultrasonic transducers. The inlet and outlet are respectively opened on both sides of the ultra-thermal coupling pretreatment chamber. The heater and multiple high-frequency ultrasonic transducers are installed on the ultra-thermal coupling pretreatment chamber. High-frequency ultrasonic vibration is applied to the powder (inside) through the high-frequency ultrasonic transducers, and the powder (inside) is heated by the heater. The outlet is connected to the powder deposition firing gun head through a powder conveying pipe.

[0007] A clamping platform is set up inside the sealed experimental chamber. The particle bombardment firing head and the powder deposition firing head are located above the clamping platform. The sealed experimental chamber is connected to the vacuum system through pipelines.

[0008] The gas phase environment precision transport unit includes multiple high-pressure gas cylinders and a main gas delivery pipeline. One end of the main gas delivery pipeline is connected to the sealed experimental chamber, and the other end of the main gas delivery pipeline is connected in parallel to multiple high-pressure gas cylinders.

[0009] This invention couples a thermal field with an ultrasonic field within a super-thermal coupling pretreatment chamber (powder delivery container), upgrading it from a passive storage unit to an active powder pretreatment module. The synergistic effect of these two elements not only comprehensively solves the problems of poor flowability and high deposition threshold, but also enables in-situ modification and synthesis of powder materials. The mechanical impact energy provided by the ultrasonic field, combined with the atomic diffusion promoted by the thermal field, induces mechanical alloying during transport, pre-forming non-equilibrium microstructures such as amorphous, nanocrystalline, or supersaturated solid solutions. The thermal field provides initial activation energy for exothermic reaction systems (such as Al-Ni and Ti-B), while the instantaneous high temperature and high pressure energy generated by ultrasonic cavitation greatly accelerates reaction kinetics, controllably generating high-performance reinforcing phases such as intermetallic compounds and carbides.

[0010] This invention further integrates a multi-angle rotatable fixture, which eliminates the "shadowing effect" of complex workpieces by dynamically controlling the placement of the substrate, ensuring the uniformity of surface modification or coating preparation, and realizing full-process optimization from powder pretreatment to dynamic modification-deposition.

[0011] The in-situ composite coating preparation device of the present invention is suitable for the pretreatment and surface deposition of metals, alloys, ceramics and doped powder materials. It can realize high-performance composite coating preparation, surface strengthening and gradient coating construction, and other processes. It is widely used in industrial scenarios where it is necessary to improve the wear resistance, corrosion resistance and high temperature resistance of components. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the overall structure of the in-situ composite coating preparation device based on multi-field coupling and atmosphere control of the present invention.

[0013] Figure 2 This is a schematic diagram of the structure of the ultra-thermal coupling pretreatment chamber;

[0014] Figure 3 This is a schematic diagram of the working principle of the ultra-thermal coupling pretreatment chamber;

[0015] Figure 4 This is a schematic diagram of the rotatable experimental platform in the embodiment. Detailed Implementation

[0016] Specific Implementation Method 1: This implementation method is based on an in-situ composite coating preparation device using multi-field coupling and atmosphere control, which includes an air compressor 1, a multi-component powder storage module, an ultra-thermal coupling pretreatment chamber 6, a sealed experimental chamber 26, a vacuum system 27, and a gas phase environment precision transport unit. The multi-component powder storage module includes multiple powder storage devices. The air nozzle of the air compressor 1 is connected in parallel to each powder storage device through a gas conveying pipe 3. The first powder outlet of each powder storage device is connected to the particle bombardment firing head 12 through a first powder conveying pipe 4. The second powder outlet of each powder storage device is connected to the feed port of the ultra-thermal coupling pretreatment chamber 6 through a second powder conveying pipe 5.

[0017] The superheated coupling pretreatment chamber 6 includes an inlet, an outlet 8, a heater 19, and multiple high-frequency ultrasonic transducers. The inlet and outlet 8 are respectively opened on both sides of the superheated coupling pretreatment chamber 6. The heater 19 and multiple high-frequency ultrasonic transducers are installed on the superheated coupling pretreatment chamber 6. High-frequency ultrasonic vibration is applied to the powder (inside) through the high-frequency ultrasonic transducers, and the powder (inside) is heated through the heater 19. The outlet 8 is connected to the powder deposition firing gun head 13 through a powder conveying pipe.

[0018] A clamping platform is provided inside the sealed experimental chamber. The particle bombardment firing head 12 and the powder deposition firing head 13 are located above the clamping platform. The sealed experimental chamber is connected to the vacuum system 27 through the pipeline 27-1.

[0019] The gas phase environment precision transport unit includes multiple high-pressure gas cylinders and a main gas delivery pipeline. One end of the main gas delivery pipeline is connected to the sealed experimental chamber 26, and the other end of the main gas delivery pipeline is connected in parallel to multiple high-pressure gas cylinders.

[0020] In this embodiment, the clamping table is a multi-angle rotating clamp 28. By controlling the placement position of the base workpiece, the "shadowing effect" of complex workpieces is eliminated, ensuring the uniformity of surface modification or coating preparation.

[0021] This embodiment uses an ultra-thermal coupling pretreatment chamber to perform "thermal-ultrasonic" synergistic pretreatment of powder to simultaneously improve transportability, lower the deposition threshold, and achieve in-situ material synthesis, realizing a process method that combines ultra-thermal coupling pretreatment of powder with dynamic deposition control.

[0022] This embodiment of the in-situ composite coating preparation device based on multi-field coupling and atmosphere control is applicable to various powder materials such as metals, alloys, and ceramics. It can realize the integration of coating preparation and surface modification, and has the advantages of high processing efficiency, high resource recovery rate, and convenient operation. It is especially suitable for the surface strengthening needs of complex components in aerospace, machinery manufacturing and other fields.

[0023] Specific Implementation Method Two: The difference between this implementation method and Specific Implementation Method One is that a pressure-flow regulator 2 is installed on each gas delivery pipeline 3.

[0024] Specific Implementation Method 3: This implementation method differs from Specific Implementation Method 1 or 2 in that the multi-component powder storage module includes three powder storage devices.

[0025] Specific Implementation Method Four: This implementation method differs from Specific Implementation Method Three in that the three powder storage devices are a first type of powder storage device 9, a second type of powder storage device 10, and a third type of powder storage device 11. The first type of powder storage device 9 stores metal-based powder, the second type of powder storage device 10 stores ceramic particles, and the third type of powder storage device 11 stores rare earth powder or reinforcing phase powder.

[0026] The reinforcing phase powder described in this embodiment can be a carbide powder (such as silicon carbide, titanium carbide, tungsten carbide, etc.), a nitride powder (such as silicon nitride, boron nitride, etc.), or a MAX phase powder (such as Ti3SiC2, Ti3AlC, etc.).

[0027] Specific Implementation Method 5: This implementation method differs from Specific Implementation Methods 1 to 4 in that a control valve is installed on each No. 1 powder conveying pipe 4.

[0028] Specific Implementation Method Six: This implementation method differs from Specific Implementation Methods One to Five in that a control valve is installed on each No. 2 powder conveying pipe 5.

[0029] Specific Implementation Method Seven: This implementation method differs from Specific Implementation Methods One to Six in that a vacuum valve is installed on pipeline 27-1.

[0030] Specific Implementation Method Eight: This implementation method differs from Specific Implementation Methods One to Seven in that each high-pressure gas cylinder is equipped with a flow meter on the branch line connecting to the main gas delivery pipeline.

[0031] Specific Implementation Method Nine: This implementation method differs from Specific Implementation Methods One to Eight in that an online gas composition analyzer 29 is installed on the sealed experimental chamber 26.

[0032] Specific Implementation Method 10: This implementation method differs from Specific Implementation Methods 1 to 9 in that a pressure sensor 30 is installed inside the sealed experimental chamber 26.

[0033] Example: This example of an in-situ composite coating preparation device based on multi-field coupling and atmosphere control includes an air compressor 1, a multi-component powder storage module, an ultra-thermal coupling pretreatment chamber 6, a sealed experimental chamber 26, a vacuum system 27, and a gas phase environment precision transport unit. The multi-component powder storage module includes three powder storage devices. The air nozzle of the air compressor 1 is connected in parallel to each powder storage device through a gas conveying pipe 3. The first powder outlet of each powder storage device is connected to the particle bombardment firing head 12 through a first powder conveying pipe 4. The second powder outlet of each powder storage device is connected to the feed port of the ultra-thermal coupling pretreatment chamber 6 through a second powder conveying pipe 5.

[0034] The superheated coupling pretreatment chamber 6 includes an inlet, an outlet 8, a heater 19, and three high-frequency ultrasonic transducers. The inlet and outlet 8 are respectively opened on both sides of the superheated coupling pretreatment chamber 6. The heater 19 is located at the bottom of the superheated coupling pretreatment chamber 6. The powder is heated by the heater 19 through the heat-conducting medium 20 (such as heat-conducting oil or metal-based heat-conducting plate). The top of the superheated coupling pretreatment chamber 6 is provided with a first high-frequency ultrasonic transducer 15, a second high-frequency ultrasonic transducer 16, and a third high-frequency ultrasonic transducer 17. High-frequency ultrasonic vibration is applied to the powder (inside) through the high-frequency ultrasonic transducers. The outlet 8 is connected to the powder deposition firing gun head 13 through a powder conveying pipe.

[0035] A clamping platform is provided inside the sealed experimental chamber. The clamping platform is a rotatable experimental platform 28. The particle bombardment emission head 12 and the powder deposition emission head 13 are located above the rotatable experimental platform 28. The sealed experimental chamber is connected to the vacuum system 27 through the pipeline 27-1, which is used to evacuate and maintain the pressure of the experimental chamber.

[0036] The gas phase environment precision transport unit includes multiple high-pressure gas cylinders and a main gas delivery pipeline. One end of the main gas delivery pipeline is connected to the sealed experimental chamber 26, and the other end of the main gas delivery pipeline is connected in parallel to multiple high-pressure gas cylinders. The multiple high-pressure gas cylinders are respectively filled with inert protective gas, reactive gas and dilution gas. A flow meter 25 is installed on the branch line connecting each high-pressure gas cylinder to the main gas delivery pipeline. An online gas composition analyzer 29 is installed on the sealed experimental chamber 26 and is connected to the chamber through a sampling pipeline to monitor the atmospheric composition in the chamber in real time. A pressure sensor 30 is used to monitor the internal pressure of the experimental chamber and feed it back to the control system to realize closed-loop control of atmosphere and pressure.

[0037] like Figure 4 As shown, the irregularly shaped component to be processed is installed on a rotatable experimental platform 28. The rotatable experimental platform 28 can rotate so that the key surface of the workpiece forms a predetermined angle with the spray direction of the particle bombardment firing head 12 and the powder deposition firing head 13.

[0038] After the workpiece is clamped, close the door of the sealed experimental chamber 26 and start the vacuum system 27 to reduce the pressure inside the chamber to the preset vacuum level (10). -3 The pressure inside the chamber is reduced to a predetermined vacuum level (Pa) to remove residual air and moisture. Ideally, the pressure inside the chamber is reduced to a predetermined vacuum level to fully remove residual air and moisture. Then, the high-pressure gas storage and flow regulation module is opened, and high-pressure protective gas or reactive gas is proportionally injected from the high-pressure gas cylinder into the sealed experimental chamber 26. The gas flow control valve fine-tunes the flow rate of each gas path. The composition and pressure of the atmosphere inside the chamber are monitored in real time by an online gas composition analyzer 29 and a pressure sensor 30. When the atmospheric composition and pressure reach the set values, the system is kept in a stable operating condition. If necessary, multiple evacuation-recharging cycles can be used to obtain a higher purity working atmosphere.

[0039] After the atmosphere stabilizes, the thermal-ultrasonic activation powder feeding unit is activated. The thermal field control console 18 is turned on, driving the heater 19 to operate. A uniform thermal field is applied to the powder ultra-thermal coupling pretreatment chamber 6 through the heat-conducting medium, causing the temperature inside the chamber to gradually rise along a preset heating curve to the target temperature range (200℃). During the heating and holding process, adsorbed water, low-boiling-point impurities, and weakly bound gases on the powder surface are removed. Subsequently, the ultrasonic parameter control console 14 is turned on, and the ultrasonic frequency (40kHz) and power (1500W) are adjusted to provide a high-frequency electrical signal to the top high-frequency ultrasonic transducer. A strong sound field is formed inside the pretreatment chamber 6 using the high-frequency ultrasonic activation module, causing the powder in the thermal field to vibrate violently and move relative to each other under the action of acoustic cavitation and acoustic flow. This achieves the deagglomeration and refinement of powder agglomerates, enhancing the dispersibility and surface activity of the powder particles. By controlling the ultrasonic power and action time, the intensity of the ultra-thermal coupling treatment can be adjusted according to different powder systems.

[0040] During powder pretreatment, the air compressor 1 in the air compression powder delivery module continuously provides a stable source of compressed air. After adjustment by the pressure-flow regulator 2, a portion of the compressed gas enters each powder storage device through the gas delivery pipeline 3, carrying the metal-based powder, ceramic particles, and reinforcing phase powder from the bottom of the storage tank into the first powder delivery pipeline 4 and the second powder delivery pipeline 5, respectively. The powder entering the ultra-thermal coupling pretreatment chamber 6 through the second powder delivery pipeline 5 undergoes activation treatment under the action of the ultra-thermal coupling unit, and is then transported to the powder deposition firing head 13 through the discharge port 8 and subsequent flexible powder delivery pipeline. The powder directly transported through the powder delivery pipeline 4 does not enter the pretreatment chamber, but is directly supplied to the particle bombardment firing head 12 for high-speed particle bombardment treatment of the substrate surface.

[0041] After powder activation and powder supply stabilization are completed, the rotary drive motor of the rotatable multi-angle clamping experimental platform is activated, causing the workpiece to rotate around the vertical axis at a preset speed (15 r / min). Simultaneously, the particle bombardment launcher 12 is activated, using compressed gas to propel untreated hard particles at high speed onto the workpiece surface. Under the stable atmosphere of the sealed experimental chamber 26, the substrate surface is strengthened and deposited, forming a rough substrate layer that is beneficial for the metallurgical bonding of subsequent composite coatings. As needed, the incident angle and spray distance between the particle bombardment launcher 12 and the workpiece surface can be adjusted, and the workpiece position can be adjusted using the lifting assembly and the rotatable experimental platform to achieve full coverage bombardment of irregular and complex surfaces.

[0042] After strengthening or deposition on the substrate surface, the workpiece is kept rotating, the particle bombardment firing head 12 is turned off or its flow rate is reduced, and the powder deposition firing head 13 is turned on to spray the composite powder pretreated by ultra-thermal coupling from the nozzle onto the pretreated substrate surface. Depending on the selected process, subsequent heat treatment is performed in conjunction with a flame torch during the spraying process, causing the powder to melt, diffuse, or undergo solid-phase sintering on the substrate surface, forming a dense, metallurgically bonded in-situ composite coating. By adjusting the ratio of the three types of functional powders, the powder delivery flow rate, and the rotational speed and fixture posture of the rotatable experimental platform, gradient composite coatings or multilayer structure coatings with adjustable composition and microstructure can be obtained in different areas of the same component.

[0043] In this embodiment, ceramic particles such as Al2O3 and ZrO2 are added to the first type of powder storage device 9, metal powders such as nickel, copper, and aluminum are added to the second type of powder storage device 10, and rare earth powders (such as Y2O3 and CeO2) or reinforcing phase powders (such as carbide, nitride, or MAX phase powder) are stored in the third type of powder storage device 11. The first type of powder storage device 9 transports ceramic particles to the microparticle bombardment firing head 12 via a first powder conveying pipe 4. The ceramic particles and metal powders are transported to the ultra-thermal coupling pretreatment chamber 6 via a second powder conveying pipe 5. Simultaneously, the high-frequency ultrasonic activation module and the controllable thermal field loading module are activated. After thermal-ultrasonic synergistic powder pretreatment, ceramic particles coated with metal powder are obtained, and the powder is transported to the powder deposition firing head 13 via the powder conveying pipe. This achieves supersonic microparticle bombardment strengthening of the surface coating after coating preparation on the workpiece surface, effectively improving the surface hardness of the coating and introducing residual compressive stress.

[0044] In this embodiment, a display 35 is connected to an ultrasonic field control console 14, a thermal field control console 18, a pressure-flow regulator 2, a vacuum system 27, a gas composition and pressure detection module 29, and a gas flow control flow meter.

[0045] This embodiment couples the thermal field and the ultrasonic field to the powder feeding tank, upgrading it from a passive storage unit to an active powder pretreatment module. The synergistic effect of the two not only comprehensively solves the problems of poor flowability and high deposition threshold, but also realizes in-situ modification and synthesis of powder materials.

[0046] In this embodiment, during the coating formation stage, the atmosphere and pressure inside the sealed experimental chamber 26 are continuously monitored by an online gas composition analyzer 29 and a pressure sensor 30. If the detection results deviate from the set values, compensation and adjustment are performed through a high-pressure gas storage and flow regulation module or a vacuum system 27 to ensure that the coating grows under stable atmosphere and pressure conditions. After the coating preparation is completed, the powder supply and rotation drive are stopped, and the temperature of the powder superheated coupling pretreatment chamber 6 and the sealed experimental chamber 26 is gradually reduced. Once the temperature drops to a safe range, inert gas or air is slowly introduced into the sealed experimental chamber to atmospheric pressure. The chamber door is then opened, the workpiece is removed, and the preparation of the in-situ composite coating with multi-field coupling and atmosphere control is completed.

Claims

1. An in-situ composite coating preparation device based on multi-field coupling and atmosphere control, characterized in that... The in-situ composite coating preparation device includes an air compressor (1), a multi-component powder storage module, an ultra-thermal coupling pretreatment chamber (6), a sealed experimental chamber (26), a vacuum system (27), and a gas phase environment precision transport unit. The multi-component powder storage module includes multiple powder storage devices. The air nozzle of the air compressor (1) is connected in parallel with each powder storage device through a gas conveying pipe (3). The first powder outlet of each powder storage device is connected to the particle bombardment firing head (12) through a first powder conveying pipe (4). The second powder outlet of each powder storage device is connected to the feed port of the ultra-thermal coupling pretreatment chamber (6) through a second powder conveying pipe (5). The superheated coupling pretreatment chamber (6) includes an inlet, an outlet (8), a heater (19), and multiple high-frequency ultrasonic transducers. The inlet and outlet (8) are respectively opened on both sides of the superheated coupling pretreatment chamber (6). The heater (19) and multiple high-frequency ultrasonic transducers are installed on the superheated coupling pretreatment chamber (6). High-frequency ultrasonic vibration is applied to the powder through the high-frequency ultrasonic transducers, and the powder is heated through the heater (19). The outlet (8) is connected to the powder deposition firing gun head (13) through the powder conveying pipe. A clamping platform is set up inside the sealed experimental chamber. The particle bombardment firing head (12) and the powder deposition firing head (13) are located above the clamping platform. The sealed experimental chamber is connected to the vacuum system (27) through a pipeline (27-1). The gas phase environment precision transport unit includes multiple high-pressure gas cylinders and a main gas transport pipeline. One end of the main gas transport pipeline is connected to the sealed experimental chamber (26), and the other end of the main gas transport pipeline is connected in parallel with multiple high-pressure gas cylinders.

2. The in-situ composite coating preparation device based on multi-field coupling and atmosphere control according to claim 1, characterized in that... Each gas delivery pipe (3) is equipped with a pressure-flow regulator (2).

3. The in-situ composite coating preparation device based on multi-field coupling and atmosphere control according to claim 1, characterized in that... The multi-component powder storage module includes three powder storage devices.

4. The in-situ composite coating preparation device based on multi-field coupling and atmosphere control according to claim 3, characterized in that... The three powder storage devices are a first type of powder storage device (9), a second type of powder storage device (10), and a third type of powder storage device (11). The first type of powder storage device (9) stores metal-based powder, the second type of powder storage device (10) stores ceramic particles, and the third type of powder storage device (11) stores rare earth powder or reinforcing phase powder.

5. The in-situ composite coating preparation device based on multi-field coupling and atmosphere control according to claim 1, characterized in that... A control valve is installed on each No. 1 powder conveying pipe (4).

6. The in-situ composite coating preparation device based on multi-field coupling and atmosphere control according to claim 1, characterized in that... A control valve is installed on each No. 2 powder conveying pipe (5).

7. The in-situ composite coating preparation device based on multi-field coupling and atmosphere control according to claim 1, characterized in that... A vacuum valve is installed on the pipeline (27-1).

8. The in-situ composite coating preparation device based on multi-field coupling and atmosphere control according to claim 1, characterized in that... Each high-pressure gas cylinder is equipped with a flow meter on the branch line connecting to the main gas delivery pipeline.

9. The in-situ composite coating preparation device based on multi-field coupling and atmosphere control according to claim 1, characterized in that... An online gas composition analyzer (29) is installed on the sealed experimental chamber (26).

10. The in-situ composite coating preparation device based on multi-field coupling and atmosphere control according to claim 1, characterized in that... A pressure sensor (30) is installed inside the sealed experimental chamber (26).

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