System and method for regulating and controlling metal wetting behavior in vacuum brazing process

Abstract

The invention relates to the technical field of brazing, in particular to a metal wetting behavior regulation and control system and method in the vacuum brazing process. The pretreated hard alloy, the pretreated base body and the pretreated mixed brazing filler metal are loaded into a vacuum brazing furnace, a heating and temperature control system is started, and heating is conducted according to a preset heating curve; in the heating process, according to a feedback result monitored in real time, the wetting behavior of the brazing filler metal is regulated and controlled; and the heating system is closed, so that the brazed part is naturally cooled in the vacuum environment. The hard alloy and the substrate are subjected to surface pretreatment, so that surface oxides, oil stains and other impurities are effectively removed, the wettability of the surface of the substrate is improved, and favorable conditions are provided for uniform wetting of the brazing filler metal. And a proper amount of active elements are added into the prepared mixed brazing filler metal, so that the wettability of the brazing filler metal on the hard alloy is improved. Therefore, the problem that metal wetting is not uniform in the traditional vacuum brazing process is solved.

Description

Technical Field

[0001] The invention relates to the technical field of brazing, and in particular to a system and method for regulating and controlling metal wetting behavior in a vacuum brazing process. Background Art

[0002] As one of the material connection methods, brazing is now widely used in non-heavy-load precision connection directions such as electronic packaging, precision instruments, and medical devices.

[0003] At present, in the brazing process of cemented carbide and substrate, due to the difference in physical and chemical properties between the two, the wettability of the brazing material on the two substrates is significantly different. The porosity of cemented carbide and the carbide matrix make it easy for liquid brazing material to infiltrate and absorb into its interior, while the wetting and spreading on the substrate is relatively poor, which directly affects the quality and reliability of the brazed joint. Summary of the invention

[0004] The purpose of the present invention is to provide a system and method for regulating the wetting behavior of metal during vacuum brazing, aiming to solve the problem of uneven metal wetting during traditional vacuum brazing.

[0005] To achieve the above objectives, in a first aspect, the present invention provides a method for regulating metal wetting behavior during vacuum brazing, comprising the following steps:

[0006] Carry out surface pretreatment on cemented carbide and substrate;

[0007] preparing a mixed solder;

[0008] The pre-treated cemented carbide, substrate and mixed brazing material are placed in a vacuum brazing furnace, and the heating and temperature control system is started to heat according to a predetermined heating curve;

[0009] During the heating process, the wetting behavior of the solder is regulated based on the feedback results of real-time monitoring;

[0010] Turn off the heating system and allow the brazed parts to cool naturally in a vacuum environment.

[0011] Among them, "surface pretreatment of cemented carbide and substrate" includes:

[0012] Use a cleaning agent to clean the surface of the substrate;

[0013] Shot blasting of the carbide and substrate;

[0014] The cemented carbide and the substrate are degreased and then dried.

[0015] Among them, in "preparing mixed solder", it includes:

[0016] Select active elements based on factors such as the material of the cemented carbide and the substrate, operating temperature, and strength requirements;

[0017] The active element is mixed with the solder to obtain a mixed solder.

[0018] Among them, "loading the pre-treated cemented carbide, substrate and mixed brazing material into a vacuum brazing furnace, starting the heating and temperature control system, and heating according to a predetermined heating curve" includes:

[0019] Assemble the pretreated cemented carbide and the substrate according to the design requirements and place the mixed brazing material;

[0020] The furnace is evacuated to a predetermined vacuum level by a vacuum pump;

[0021] The heating system gradually increases the temperature according to a predetermined heating curve to heat the cemented carbide and the substrate.

[0022] Among them, in "regulating the wetting behavior of the solder according to the feedback results of real-time monitoring during the heating process", it includes:

[0023] Applying a magnetic field to control the flow behavior of liquid solder and achieve its uniform distribution in the weld;

[0024] The temperature, pressure, wettability and other parameters in the brazing process are monitored in real time through sensors, and the working parameters of the wetting behavior control device are adjusted according to the feedback results.

[0025] Among them, "turn off the heating system to allow the brazed parts to cool naturally in a vacuum environment" includes:

[0026] Turn off the heating system and let the brazed parts cool naturally to room temperature in a vacuum environment;

[0027] Check the appearance of the weld and assess the strength and reliability of the brazed joint.

[0028] In the second aspect, a system for regulating the wetting behavior of metal during vacuum brazing adopts the method for regulating the wetting behavior of metal during vacuum brazing described in the first aspect, and includes a cleaning module, a preparation module and a heating module. The cleaning module is used to clean the cemented carbide and the substrate; the preparation module is used to prepare mixed brazing material, and the heating module is used to heat the cemented carbide and the substrate.

[0029] The present invention discloses a method for regulating the wetting behavior of metals during vacuum brazing, comprising the following steps: performing surface pretreatment on cemented carbide and substrate; preparing a mixed brazing material; placing the pretreated cemented carbide, substrate and mixed brazing material into a vacuum brazing furnace, starting a heating and temperature control system, and heating the material according to a predetermined heating curve; regulating the wetting behavior of the brazing material according to the feedback results of real-time monitoring during the heating process; and shutting down the heating system to allow the brazed parts to cool naturally in a vacuum environment. By performing surface pretreatment on cemented carbide and substrate, impurities such as surface oxides and oil stains are effectively removed, the wetting properties of the substrate surface are improved, and favorable conditions are provided for uniform wetting of the brazing material. An appropriate amount of active elements are added to the prepared mixed brazing material, which can react with carbides in cemented carbide to generate low-melting-point compounds, thereby significantly improving the wettability of the brazing material on the cemented carbide, while maintaining or improving the wetting and spreading ability on the substrate. Thus, the problem of uneven metal wetting during traditional vacuum brazing is solved. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0031] Figure 1 The present invention provides a flow chart of a method for regulating metal wetting behavior during vacuum brazing.

[0032] Figure 2 It is a flow chart of surface pretreatment of cemented carbide and substrate.

[0033] Figure 3 It is a flow chart for preparing mixed solder.

[0034] Figure 4 It is a flow chart of placing the pretreated cemented carbide, substrate and mixed brazing material into a vacuum brazing furnace, starting the heating and temperature control system, and heating according to a predetermined heating curve.

[0035] Figure 5 It is a flow chart for regulating the wetting behavior of the solder according to the feedback results of real-time monitoring during the heating process.

[0036] Figure 6 This is a flow chart of turning off the heating system to allow the brazed parts to cool naturally in a vacuum environment. DETAILED DESCRIPTION

[0037] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0038] See also Figures 1 to 6 In a first aspect, the present invention provides a method for regulating metal wetting behavior during vacuum brazing, comprising the following steps:

[0039] S1 performs surface pretreatment on cemented carbide and substrate;

[0040] S11 uses a cleaning agent to clean the surface of the substrate;

[0041] Specifically, the cleaning agent is evenly applied to the surface of the substrate, and the cleaning agent is ensured to fully contact and penetrate into the tiny pores on the surface of the substrate by soaking, brushing or spraying. During the cleaning process, a brush or spray gun is used for brushing or spraying to enhance the cleaning effect; after cleaning, it is thoroughly rinsed with clean water or solvent to remove the residual cleaning agent, and the cleaned substrate is dried to prevent the residual moisture from causing adverse effects on subsequent processes.

[0042] S12 performs sandblasting on the cemented carbide and substrate;

[0043] Specifically, the cemented carbide and the substrate are sandblasted with a sandblasting medium to remove the surface oxide layer, rust layer, etc., to improve the surface roughness and enhance the bonding force between the brazing material and the substrate. After the sandblasting is completed, the substrate is cleaned and dried as necessary to ensure that there is no impurity residue on the surface.

[0044] S13 degreases the cemented carbide and the substrate and then dries them.

[0045] Specifically, the degreasing agent is evenly applied to the surface of the substrate, and the degreasing treatment is performed by soaking, brushing or spraying. During the degreasing process, brushing or spraying is performed to enhance the degreasing effect; after the degreasing is completed, it is thoroughly rinsed with clean water or solvent to remove the residual degreasing agent; the degreased substrate is dried.

[0046] S2 prepares mixed solder;

[0047] S21 selects active elements based on the material of cemented carbide and substrate, operating temperature, strength requirements and other factors;

[0048] Specifically, the chemical composition and physical properties of the cemented carbide and the matrix are analyzed to determine their material characteristics. According to the process conditions such as working temperature and strength requirements, appropriate active elements (such as titanium, zirconium, niobium, etc.) are selected to improve the wettability and bonding strength of the brazing filler metal.

[0049] S22: The active element is mixed with the solder to obtain a mixed solder.

[0050] Specifically, the mass of active elements and solder is accurately weighed to ensure that the mixing ratio meets the process requirements. The active elements and solder are placed in the mixing equipment and fully mixed to ensure that the active elements are evenly distributed in the solder. After the mixing is completed, the mixed solder is tested and evaluated as necessary to ensure that its quality meets the process requirements.

[0051] S3: The pre-treated cemented carbide, substrate and mixed brazing material are placed into a vacuum brazing furnace, and the heating and temperature control system is started to heat according to a predetermined heating curve;

[0052] S31 assembles the pretreated cemented carbide and the substrate according to the design requirements and places the mixed brazing material;

[0053] Specifically, according to the design requirements, the cemented carbide and the substrate are assembled accurately to ensure that the joint gap and position meet the process requirements. The mixed brazing material is evenly placed in the joint gap to ensure that the brazing material can fully wet and fill the gap. The assembled brazing parts are fixed in the vacuum brazing furnace using a fixture to ensure that they will not move or deform during the heating process.

[0054] S32: evacuating the furnace to a predetermined vacuum degree through a vacuum pump;

[0055] Specifically, the vacuum pump is started to extract the air in the vacuum brazing furnace to reduce the oxygen content in the furnace and prevent oxidation reaction during the brazing process. The vacuum indicator is monitored to ensure that the vacuum degree in the furnace reaches a predetermined value.

[0056] The S33 heating system heats the cemented carbide and the substrate gradually according to a predetermined heating curve.

[0057] Specifically, the heating system is started and the temperature is gradually increased according to the predetermined heating curve. The heating curve should be set according to factors such as the material and thickness of the cemented carbide and the substrate and the melting point of the mixed solder. During the heating process, the temperature and power output of the heating system are monitored to ensure a smooth and uniform heating process. When the temperature in the furnace reaches the predetermined value, it is maintained for a preset time to ensure that the mixed solder is fully melted and wets the surface of the substrate.

[0058] S4 regulates the wetting behavior of the solder according to the feedback results of real-time monitoring during the heating process;

[0059] S41 applies a magnetic field to regulate the flow behavior of liquid solder to achieve its uniform distribution in the weld;

[0060] Specifically, during the heating process, the magnetic field generating device is started to generate a magnetic field. The magnetic field strength should be set according to factors such as the fluidity of the liquid solder and the shape of the weld. Under the action of the magnetic field, the liquid solder flows under the action of the Lorentz force, thereby achieving uniform distribution in the weld. The magnetic field strength and the flow of the liquid solder are monitored, and the working parameters of the magnetic field generating device are adjusted in time to ensure uniform distribution of the liquid solder in the weld.

[0061] S42 uses sensors to monitor parameters such as temperature, pressure, and wettability during the brazing process in real time, and adjusts the working parameters of the wetting behavior control device based on the feedback results.

[0062] Specifically, monitoring equipment such as temperature sensors, pressure sensors and wettability monitoring sensors are installed in the vacuum brazing furnace to monitor parameters such as temperature, pressure and wettability during the brazing process in real time. The monitoring equipment will feed back the real-time monitoring data to the control system, and the control system will automatically adjust the working parameters (magnetic field strength, heating power, etc.) of the wetting behavior control device according to the feedback results to ensure the stability and reliability of the brazing process. During the monitoring process, pay attention to checking the accuracy and stability of the sensor to ensure the accuracy and reliability of the monitoring data.

[0063] S5 turns off the heating system to allow the brazed parts to cool naturally in a vacuum environment.

[0064] S51 Turn off the heating system and let the brazed parts cool naturally to room temperature in a vacuum environment;

[0065] Specifically, when the brazing process is completed, turn off the heating system and stop heating. Keep the vacuum degree in the vacuum brazing furnace unchanged and let the brazed parts cool naturally to room temperature in a vacuum environment. During the cooling process, avoid forced cooling or blowing on the brazed parts to prevent defects such as cracks or deformation. Monitor the temperature and pressure changes during the cooling process to ensure a smooth and uniform cooling process.

[0066] S52 inspects the appearance of welds and evaluates the strength and reliability of brazed joints.

[0067] Specifically, after cooling is completed, open the door of the vacuum brazing furnace and take out the brazed parts. Check the appearance of the weld to see if it is flat, smooth, free of cracks, pores and other defects. Evaluate the strength and reliability of the brazed joint. Use mechanical property test methods such as tensile test, shear test, bending test, as well as microscopic analysis methods such as metallographic analysis and scanning electron microscopy to evaluate and analyze the mechanical properties and microstructure of the brazed joint. Based on the evaluation results, determine whether the brazing quality meets the design requirements.

[0068] In the second aspect, a system for regulating the wetting behavior of metal during vacuum brazing adopts the method for regulating the wetting behavior of metal during vacuum brazing described in the first aspect, and includes a cleaning module, a preparation module and a heating module. The cleaning module is used to clean the cemented carbide and the substrate; the preparation module is used to prepare mixed brazing material, and the heating module is used to heat the cemented carbide and the substrate.

[0069] Beneficial effects:

[0070] 1. The present invention effectively removes impurities and oxide layers on the surface of cemented carbide and substrate, improves the cleanliness and roughness of the substrate surface, and provides good conditions for the wetting and bonding of the solder. When preparing the mixed solder, the active elements are accurately selected according to the substrate material and process requirements, and are fully mixed with the solder to ensure the wettability and bonding strength of the solder, thereby significantly improving the quality and reliability of the brazed joint.

[0071] Second, the present invention gradually heats up according to a predetermined heating curve, ensuring a smooth and uniform heating process and avoiding defects such as thermal stress and cracks caused by sudden temperature changes. During the heating process, real-time monitoring and regulation ensure the uniform distribution of liquid solder in the weld, improving the uniformity and consistency of the brazed joint. The natural cooling process avoids the risks of thermal stress and deformation caused by forced cooling, ensuring the stability and reliability of the brazed joint.

[0072] 3. The present invention uses automated equipment and sensors to monitor parameters such as temperature, pressure, wettability, etc. in real time during the brazing process, and automatically adjusts the working parameters according to the feedback results, which significantly improves production efficiency. It provides a basis for standardization and automation in the production process and reduces the errors and uncertainties of manual operations.

[0073] What is disclosed above is only a preferred embodiment of a system and method for regulating metal wetting behavior during vacuum brazing of the present invention. Of course, this cannot be used to limit the scope of rights of the present invention. Ordinary technicians in this field can understand that all or part of the processes of the above embodiments and equivalent changes made in accordance with the claims of the present invention still fall within the scope of the invention.

Claims

1. A method for regulating metal wetting behavior during vacuum brazing, characterized in that: The following steps are involved: Carry out surface pretreatment on cemented carbide and substrate; preparing a mixed solder; The pre-treated cemented carbide, substrate and mixed brazing material are placed in a vacuum brazing furnace, and the heating and temperature control system is started to heat according to a predetermined heating curve; During the heating process, the wetting behavior of the solder is regulated based on the feedback results of real-time monitoring; Turn off the heating system and allow the brazed parts to cool naturally in a vacuum environment.

2. The method for controlling the metal wetting behavior during vacuum brazing according to claim 1, characterized in that: In "Surface preparation of cemented carbide and substrate", it includes: Use a cleaning agent to clean the surface of the substrate; Shot blasting of the carbide and substrate; The cemented carbide and the substrate are degreased and then dried.

3. The method for controlling the metal wetting behavior during vacuum brazing according to claim 2, characterized in that: In "preparing mixed solder", it includes: Select active elements based on factors such as the material of the cemented carbide and the substrate, operating temperature, and strength requirements; The active element is mixed with the solder to obtain a mixed solder.

4. The method for controlling the metal wetting behavior during vacuum brazing according to claim 3, characterized in that: In "loading the pre-treated cemented carbide, substrate and mixed brazing material into a vacuum brazing furnace, starting the heating and temperature control system, and heating according to a predetermined heating curve", it includes: Assemble the pretreated cemented carbide and the substrate according to the design requirements and place the mixed brazing material; The furnace is evacuated to a predetermined vacuum degree by a vacuum pump; The heating system gradually increases the temperature according to a predetermined heating curve to heat the cemented carbide and the substrate.

5. The method for controlling the metal wetting behavior during vacuum brazing according to claim 4, characterized in that: In "Controlling the wetting behavior of the solder based on real-time monitoring feedback during the heating process", it includes: Applying a magnetic field to control the flow behavior of liquid solder and achieve its uniform distribution in the weld; The temperature, pressure, wettability and other parameters in the brazing process are monitored in real time through sensors, and the working parameters of the wetting behavior control device are adjusted according to the feedback results.

6. The method for controlling the wetting behavior of metal during vacuum brazing according to claim 5, characterized in that: In "turning off the heating system to allow the brazed parts to cool naturally in a vacuum environment", it includes: Turn off the heating system and let the brazed parts cool naturally to room temperature in a vacuum environment; Inspect the appearance of welds and assess the strength and reliability of brazed joints.

7. A system for regulating metal wetting behavior during vacuum brazing, using the method for regulating metal wetting behavior during vacuum brazing according to any one of claims 1 to 6, characterized in that: It comprises a cleaning module, a preparation module and a heating module. The cleaning module is used for cleaning the cemented carbide and the matrix; the preparation module is used for preparing mixed solder, and the heating module is used for heating the cemented carbide and the matrix.

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