Resistance brazing method and system for saw blade tip welding

Abstract

The application discloses a resistance brazing method and system for saw blade bit welding, and the method comprises the following steps: placing and temporarily fixing a bit on a welding position of a saw blade; attaching two electrode sheets on two power contact surfaces of the bit; controlling a welding power output detection power, and detecting a contact resistance between the electrode sheet and the bit; when the contact resistance is greater than a resistance threshold value, disconnecting the power output of the welding power, and controlling a relative friction movement between the electrode sheet and the power contact surface, and re-detecting the contact resistance; the detection of the contact resistance and the execution of the friction movement are cyclically performed until the detected resistance is less than or equal to the resistance threshold value, and the welding power output of the welding power is controlled. The above method introduces a closed-loop control mechanism of detection power, contact resistance judgment, electrode friction and cyclic adjustment before formal brazing, and effectively solves the problem that the contact resistance is too high and unstable due to oxidation, impurities or loose fitting on the surface of the bit in the prior art.

Description

Technical Field

[0001] This invention relates to the field of resistance brazing technology, and in particular to a resistance brazing method and system for welding saw blade heads. Background Technology

[0002] In the hardware tool manufacturing industry, saw blades are widely used for cutting and processing materials such as wood, stone, and metal. To improve the cutting performance and service life of saw blades, high-hardness alloy cutting tips are usually welded to the saw teeth of the saw blade body.

[0003] Currently, resistance brazing is a common welding process for bonding alloy cutting heads to the saw blade substrate. Its basic principle is to use a clamp to press the electrode sheet onto the alloy cutting head, apply a large current through a resistance welding power source, and utilize the Joule heat generated when the current flows through the contact resistance and the material's own resistance to melt the brazing filler metal placed between the cutting head and the welding groove, thereby firmly bonding the two together.

[0004] However, in the actual resistance brazing production process, the existing technology has the following significant defects and shortcomings: Firstly, in actual processing, the surface of the alloy cutting tip inevitably has microscopic unevenness, or is covered with oxide layers, oil, impurities, etc., which often prevents the electrode plate from achieving an ideal tight fit with the alloy cutting tip. This poor contact results in random and high initial contact resistance, affecting the welding quality.

[0005] Secondly, existing resistance brazing methods typically involve directly applying a preset high welding power (high current) to heat the blade after clamping and assembly. If a high welding current is applied directly when the contact resistance is too high or unevenly distributed, excessive heat will be generated instantaneously at the local contact points between the electrode and the saw head. This not only causes a sudden rise in local temperature, easily leading to burns or thermal deformation of the alloy saw head surface, but also results in uncontrolled downward heat conduction, causing uneven heating of the brazing filler metal at the bottom, premature melting, or even spattering. Ultimately, this results in incomplete welds, lack of fusion, or porosity, severely impacting the welding quality and yield of the saw blade.

[0006] Therefore, there is an urgent need in this field for a new resistance brazing method. Summary of the Invention

[0007] The purpose of this invention is to provide a resistance brazing method and system for welding saw blade heads that can effectively avoid various welding defects caused by poor contact in order to solve the above-mentioned technical problems.

[0008] To achieve the above objectives, the present invention provides a resistance brazing method for welding saw blade tips, comprising: The cutter head to be welded is placed and temporarily fixed to the welding position on the saw blade, and brazing filler metal is provided on the welding contact surface between the cutter head and the welding position; Two electrode plates electrically connected to a welding power source are provided, and the two electrode plates are respectively attached to two power contact surfaces on the cutting head that are different from the welding contact surface; The welding power supply outputs a detection power that is less than the welding power required to melt the brazing filler metal, and the contact resistance between the electrode plate and the cutting head is detected. When the contact resistance is greater than a preset resistance threshold, the power output of the welding power source is disconnected, and relative frictional movement is controlled between the electrode sheet and the power contact surface. When the frictional motion completes a preset number of times or continues for a preset duration, the welding power supply is controlled to output the detection power again, and the contact resistance is re-detected; The contact resistance detection and frictional motion are repeated in this cycle until the detected resistance is less than or equal to the resistance threshold, at which point the welding power source is controlled to output the welding power.

[0009] Preferably, the trajectory of the frictional motion is a uniform trajectory covering the entire power contact surface.

[0010] Ideally, during the frictional motion, the speed and frictional pressure should be kept constant.

[0011] Preferably, the method for detecting the contact resistance includes: Multiple sets of voltage and current between the electrode plates and the cutting head are continuously collected, and the average value of the multiple sets of voltage and current is calculated using Ohm's law to obtain the contact resistance.

[0012] Preferably, when the number of cycles of the frictional motion reaches a preset threshold and the contact resistance is still greater than the resistance threshold, the power output of the welding power source is stopped and a shutdown instruction is issued.

[0013] Preferably, the welding power output process includes an initial first stage and a second stage of fusion welding; In the initial stage, the welding power source outputs a first current value for a first duration, causing the temperature of the cutting head to rise from room temperature. When the temperature of the cutting head is detected to reach 50%-80% of the melting point of the brazing filler metal, the current output by the welding power supply is switched to a second current value that is less than the first current value.

[0014] Preferably, during the second stage of current output, the power supply is continuously supplied for a second duration so that the molten brazing filler metal can fully wet the welding contact surface under the action of contact pressure and surface tension.

[0015] The present invention also provides a resistance brazing system for welding saw blade tips, comprising a welding power source, an electrode plate electrically connected to the welding power source, and a moving mechanism for controlling the movement of the electrode plate, wherein the resistance brazing system operates based on the resistance brazing method described above.

[0016] The present invention also provides a resistance brazing system, comprising: One or more processors; Memory; and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, the programs including instructions for performing the resistance brazing method as described above.

[0017] The present invention also provides a computer-readable storage medium comprising a computer program that can be executed by a processor to perform the resistance brazing method as described above.

[0018] Compared with existing technologies, the resistance brazing method provided by the above-mentioned technical solution effectively solves the problem of excessively high and unstable contact resistance caused by oxidation, impurities, or poor adhesion of the alloy tip surface in existing technologies by introducing a closed-loop control mechanism for power detection, contact resistance judgment, electrode friction, and cyclic adjustment before formal brazing. Through automated frictional motion, the contact interface is actively optimized, ensuring that the contact state meets the predetermined requirements before applying high-energy welding power, thereby avoiding welding defects such as uneven current distribution, localized overheating, brazing filler metal spatter, and alloy tip deformation caused by excessive contact resistance. This solution significantly improves the uniformity of heat transfer and the controllability of the process, effectively enhancing the connection strength of the brazed joint and the consistency of product quality. Attached Figure Description

[0019] Figure 1 This is a structural diagram of a saw blade with a cutting head in an embodiment of the present invention.

[0020] Figure 2 for Figure 1 Enlarged view of part A in the middle.

[0021] Figure 3 This is a flowchart of the resistance brazing method in an embodiment of the present invention.

[0022] Figure 4 This is a diagram showing the change in current output by the welding power source during the welding stage in an embodiment of the present invention. Detailed Implementation

[0023] To illustrate the technical content, structural features, objectives, and effects of the present invention in detail, the following description is provided in conjunction with the embodiments and accompanying drawings.

[0024] This invention discloses a resistance brazing method for welding saw blade tips, which is suitable for welding carbide tips, cermet tips or other wear-resistant tips to circular saw blades, band saw blades or other substrates with saw tooth welding positions 12.

[0025] like Figure 1 and Figure 2 This method utilizes two electrode plates to contact the two power contact surfaces M2 of the cutter head 11 respectively, so that the welding current forms a path through the cutter head 11 and the welding area between it and the saw blade base 10. The brazing filler metal is melted by resistance heating, and the contact resistance between the electrode plates and the cutter head 11 is kept within a controllable range by low-power detection and friction adjustment before welding.

[0026] Please refer to the following: Figure 1 value Figure 3 The resistance brazing method in this embodiment includes the following steps: S1: Place the cutter head 11 to be welded and temporarily fix it to the pre-set welding position 12 of the saw blade base 10. Pre-place sheet-like or paste-like brazing filler metal on the welding contact surface M1 between the cutter head 11 and the welding position 12.

[0027] Specifically, the welding position 12 can be a groove, stepped groove, clamping groove, or connecting surface provided at the front end, tooth top, or tooth side of the saw tooth, the shape of which is adapted to the bottom or side contour of the cutter head 11, so as to initially position the cutter head 11. A welding contact surface M1 is formed between the cutter head 11 and the welding position 12, and brazing filler metal is provided at the welding contact surface M1. The brazing filler metal can be a brazing filler sheet, brazing filler foil, brazing filler paste, brazing filler powder pre-coated layer, or a brazing filler layer pre-plated on the surface of the cutter head 11 or the saw blade substrate 10.

[0028] After the cutter head 11 is placed in the welding position 12, it can be temporarily fixed by mechanical clamps, elastic blocks, or electrode pre-pressure. The purpose of temporary fixing is to keep the cutter head 11 in a stable position during contact resistance testing, friction adjustment, and subsequent heating welding, preventing the brazing filler metal from shifting before melting. Temporary fixing does not require the formation of a final connection; it is only necessary to ensure that the welding contact surface M1 of the cutter head 11 maintains a predetermined relative position with the brazing filler metal and saw blade welding position 12.

[0029] S2: Attach the two electrode plates, which are electrically connected to the welding power source, to the two power contact surfaces M2 on the cutter head 11 that are different from the welding contact surface M1.

[0030] S3: Controls the output detection power of the welding power source. The detection power is less than the welding power that melts the brazing filler metal.

[0031] Specifically, after the two electrode plates contact the cutting head 11, welding heating is not performed directly. Instead, the welding power supply outputs a detection power. The detection power is less than the welding power required to melt the brazing filler metal. Its function is not to heat the welding area, but to detect the contact state between the electrode plates and the cutting head 11. For example, when using a pulsed power supply, the IGBT drive module can be controlled to output detection pulses with a duty cycle of 5% to 15%, causing a low-amplitude current to flow through the path. Since the current and duration of the detection phase are limited, the Joule heat generated in the path is insufficient to make the brazing filler metal reach its melting point, nor is it sufficient to cause thermal damage to the surface of the cutting head 11.

[0032] S4: Real-time acquisition of output voltage and current data between the electrode plate and the cutting head, and calculation of contact resistance based on Ohm's law.

[0033] To improve the reliability of the test results, the resistance of the electrode sheet itself and the circuit resistance can be compensated before calculation. For example, a fixed circuit resistance value can be obtained in advance during the no-load calibration of the equipment or the calibration of the standard test piece, and this fixed circuit resistance value can be subtracted from the total resistance during actual testing, thereby obtaining an actual contact resistance that is closer to the contact interface between the electrode sheet and the cutter head 11.

[0034] Contact resistance reflects the degree of contact between the electrode and the cutting head 11. If the electrode and the cutting head 11 are in good contact, the actual conductive area of ​​the contact interface is large, the current distribution is more uniform, and the contact resistance is low. If there is an oxide layer, dust, oil, or solder residue on the surface of the cutting head 11, or if there are small gaps or local point contacts between the electrode and the cutting head 11, the actual conductive area decreases, the current concentrates in local areas, and the contact resistance increases. High and unstable contact resistance will cause excessive heat concentration at the electrode contact interface during subsequent welding, resulting in local overheating of the cutting head 11, electrode adhesion, uneven solder melting, or weld joint defects. Therefore, testing the contact resistance before outputting welding power can help determine in advance whether the contact condition meets the welding requirements.

[0035] S5: Determine whether the contact resistance is higher than the preset resistance threshold. If yes, proceed to S6; otherwise, proceed to S7.

[0036] S6: This indicates that there is an oxide film or insufficient micro-contact points on the power contact surface M2 between the cutting head 11 and the electrode plate. In this case, the power output of the welding power supply is disconnected, and the electrode plate is driven to apply a reciprocating frictional motion to the surface of the cutting head 11. This motion aims to mechanically remove surface impurities and increase the contact area. After the frictional motion completes a preset number of times or lasts for a preset duration, the process returns to S3.

[0037] Once the contact resistance drops to within acceptable limits, the system automatically switches to welding power output to complete the subsequent heating and fusion process.

[0038] The physical effect of friction is that, even after processing, the surfaces of the cutting head 11 and the electrode plate typically have microscopic rough peaks. During initial bonding, the area actually involved in conductivity is only located at the tips of a few rough peaks. When an oxide film or contaminants are present at the contact interface, the conductive pathways between these rough peaks are further reduced. By maintaining a certain contact pressure and performing relative friction, the electrode plate exerts a shearing effect on the surface of the cutting head 11, breaking up localized oxide films, carrying loose impurities away from the contact area, and causing some microscopic peaks to undergo plastic deformation or be flattened, thereby increasing the actual contact area. With the increased actual contact area, the number of current channels increases, the current density per unit area decreases, the contact resistance decreases accordingly, and the heating positions during subsequent welding processes become more stable.

[0039] S7: Explanation: If the power contact surface M2 between the cutter head 11 and the electrode plate is of qualified quality, welding work can be carried out. Then control the welding power output to complete the subsequent heating and fusion process.

[0040] Because this embodiment incorporates low-power detection and friction adjustment steps based on the detection results before welding, the interface impedance before the welding current enters the cutter head 11 is within a preset range. With reduced contact resistance, heat accumulation at the electrode contact interface decreases, and more heat concentrates in the welding area formed by the cutter head 11, the brazing filler metal, and the saw blade welding position 12. This improves the stability of the brazing filler metal melting and wetting process and reduces the probability of incomplete welds, localized ablation, incomplete brazing seams, or cutter head 11 misalignment caused by poor contact.

[0041] To further optimize the contact between the electrode and the cutting head 11, the trajectory of the frictional motion is set to a uniform trajectory covering the entire power contact surface M2 during the implementation of the frictional motion. This ensures that the relative slippage between the electrode and the alloy cutting head 11 is not concentrated in a localized area, but rather forms a more evenly distributed frictional effect on the power contact surface M2. For example, reciprocating linear motion or a helical trajectory can be used to ensure the integrity of the cleaned area.

[0042] During the friction process, the pressure between the electrode plate and the cutting head 11 is kept constant between 2kN and 5kN by a servo mechanism, while the friction speed is maintained within the specified range of 5mm / s to 10mm / s. By coordinating constant pressure and speed, the surface oxide layer structure can be destroyed to the maximum extent without damaging the cutting head 11 substrate, thus eliminating physical barriers that cause high local contact resistance.

[0043] In addition, during the contact resistance testing process, a multi-point sampling and averaging method is used to filter out transient power surges or interference signals. A high-speed data acquisition module continuously collects 3 to 5 sets of voltage and current data within a detection cycle of 1 to 3 seconds. The resistance value for each set is calculated using Ohm's law, and their arithmetic mean is taken as the final contact resistance.

[0044] On the other hand, when the number of cycles of frictional motion reaches a preset threshold (e.g., 5 times) and the contact resistance is still greater than the resistance threshold, the power output of the welding power source will be stopped and a shutdown instruction will be issued.

[0045] The shutdown indication can be an audible and visual alarm, a touchscreen text prompt, a control system fault code, a host computer alarm message, or an automatic workpiece discharge signal. After shutdown, the operator or automatic detection mechanism can check whether there is oil, oxide layer, damage, or dimensional abnormalities on the surface of the cutter head 11, check whether the electrode end face is flat, check whether the fixture positioning reference is loose, and restart the welding process after troubleshooting.

[0046] For another embodiment, please refer to [the relevant documentation]. Figure 4 After the contact resistance is deemed acceptable, the formal heating and brazing stage begins. This stage is divided into a first stage of initial slow heating and a second stage of fusion welding.

[0047] In the first stage, the welding power supply outputs a first current value for a first duration (e.g., 10 to 30 seconds). The Joule heat generated by the current flowing through the contact resistance slowly raises the temperature of the cutting head 11 from room temperature. During this period, the electrode pressure remains constant to prevent changes in the contact state.

[0048] The first current value is determined based on the material, thickness, contact resistance, melting point of brazing filler metal 11, and thermal conductivity of saw blade substrate 10.

[0049] When the temperature of the cutting head 11 reaches 50% to 80% of the solder melting point, preferably 60% to 70%, as detected by the infrared sensor or current-voltage slope, a switching command is triggered to switch the output current to a smaller second current value, thus entering the second stage.

[0050] In addition, during the second stage of current output, power is continuously supplied for a second duration so that the molten brazing filler metal can fully wet the welding contact surface M1 under the action of contact pressure and surface tension.

[0051] The second duration can be set to 3 to 5 seconds. This time is used to allow the brazing filler metal to change from its initial molten state to a molten state that can spread along the welding gap and fully contact the surfaces of the cutter head 11 and the saw blade base 10.

[0052] In this embodiment, the steady heating in the first stage can avoid the rapid overheating of local areas caused by applying excessive welding power directly in a cold state, and can also allow the brazing filler metal to gradually approach the melting temperature, providing a temperature basis for the subsequent melting stage.

[0053] In the second stage, since the temperature of the cutting head 11 has increased, its resistance is higher than in the cold state. A smaller second current value can still generate sufficient heat in the cutting head 11 and the welding area. The second current value is lower than the first current value, which reduces excessive current surges and lowers the risk of solder splashing, hot cracking of the cutting head 11, or localized annealing of the saw blade substrate 10. The goal of the second stage is not to continue a slow, prolonged heating process, but to enable the solder to reach its melting point and form a molten state more quickly based on the existing temperature.

[0054] Therefore, by dividing the welding heating process into a first stage and a second stage, and reducing the current after reaching the intermediate temperature threshold, the characteristic that the resistance of the solder tip 11 increases with temperature can be utilized to transform the heating process from cold-state supplementary heating to hot-state controlled heating. This segmented approach makes the temperature change of the solder before it reaches its melting point more controllable and reduces splashing and overheating caused by excessive current during the solder melting stage.

[0055] In summary, this invention discloses a resistance brazing method for welding saw blade tips, which will be fully described below with a specific example.

[0056] In this example, the saw blade base 10 is a steel-based circular saw blade with a diameter of 350 mm, and the cutting head 11 to be welded is a carbide head. The saw blade teeth are provided with welding positions 12 that fit the bottom of the cutting head 11. A 0.10 mm thick silver-copper-zinc brazing filler metal sheet is placed between the bottom surface of the welding position 12 and the bottom surface of the cutting head 11. The melting point of the brazing filler metal is approximately 760°C. The welding equipment includes a medium-frequency inverter resistance welding power supply, two chromium-zirconium-copper electrode sheets, a moving mechanism, an infrared temperature sensor, a current sensor, a voltage acquisition module, and a controller.

[0057] At the start of welding, the mechanical fixture positions the saw blade teeth, and the feeding mechanism feeds the alloy cutter head 11 into the welding position 12, so that the brazing filler metal sheet is located between the alloy cutter head 11 and the welding position 12. The two electrode sheets are respectively attached to the left and right sides of the alloy cutter head 11, and the moving mechanism applies a contact pressure of 3.5kN.

[0058] The controller first controls the welding power supply to output detection pulses with a 10% duty cycle, and the detection lasts for 2 seconds. During this time, the current sensor and voltage acquisition module collect 5 sets of current and voltage data. After subtracting the pre-calibrated 0.25mΩ line resistance, the controller calculates the average contact resistance.

[0059] Under this operating condition, the contact resistance threshold is set to 1.0 mΩ. If the initial contact resistance is 2.6 mΩ, the controller stops outputting the detection pulse and drives the two electrode plates to reciprocate along the side of the cutter head 11. The friction speed is 8 mm / s, the friction pressure is maintained at 3.5 kN, and the friction trajectory is an up-and-down scanning trajectory covering the main contact area of ​​the side. Each friction cycle lasts 4 seconds.

[0060] After the first friction test, the contact resistance dropped to 1.4 mΩ, but was still above the resistance threshold. After the second friction test, the contact resistance dropped to 0.85 mΩ, which met the requirements. The controller then stopped the friction test and started the welding heating process.

[0061] After the contact resistance is deemed acceptable, the welding power supply enters the first stage, outputting a first current value of 1250A for 20 seconds. An infrared temperature sensor detects the temperature of the cutting head 11 near the welding area, while the controller simultaneously monitors changes in the welding voltage. When the temperature rises from room temperature to approximately 500°C, which is about 66% of the solder's melting point, the controller switches the output current to a second value of 880A. Due to the increased resistance of the cutting head 11 and the welding area as the temperature rises, the 880A current continues to generate sufficient heat to raise the solder temperature to near its melting point and initiate melting.

[0062] When the infrared temperature sensor detects that the temperature reaches 760℃, the controller maintains the second current value for 4 seconds, allowing the brazing filler metal to fully melt and spread along the gap between the bottom surface of the cutter head 11 and the saw blade welding position 12. The controller then stops the welding power output, and the electrode plates continue to maintain a pressure of 3.5kN for 8 seconds, allowing the molten brazing filler metal to solidify under pressure. After the pressure holding period, the moving mechanism slowly releases the pressure, the two electrode plates move away from the cutter head 11, and the saw blade moves to the next tooth welding position 12. The welded cutter head 11 then enters the cooling zone with the saw blade and cools naturally to room temperature.

[0063] In another preferred embodiment of the present invention, a resistance brazing system for welding saw blade tips is also disclosed, comprising a welding power source, an electrode plate electrically connected to the welding power source, and a moving mechanism for controlling the movement of the electrode plate. The resistance brazing system operates based on the resistance brazing method in the above embodiments.

[0064] The present invention also discloses another resistance brazing system, which includes one or more processors, a memory, and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, the programs including instructions for performing the resistance brazing method as described above. The processor may be a general-purpose central processing unit (CPU), a microprocessor, an application-specific integrated circuit (ASIC), or one or more integrated circuits, used to execute the relevant programs to implement the functions required by the modules in the resistance brazing system of the embodiments of this application, or to execute the resistance brazing method of the method embodiments of this application.

[0065] The present invention also discloses a computer-readable storage medium comprising a computer program executable by a processor to perform the resistance brazing method described above. The computer-readable storage medium can be any available medium accessible to a computer or a data storage device such as a server or data center integrating one or more available media. The available medium can be read-only memory (ROM), random access memory (RAM), or magnetic media, such as floppy disks, hard disks, magnetic tapes, magnetic disks, or optical media, such as digital versatile discs (DVDs), or semiconductor media, such as solid-state drives (SSDs).

[0066] This application also discloses a computer program product or computer program, which includes computer instructions stored in a computer-readable storage medium. A processor of an electronic device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the electronic device to perform the aforementioned resistance brazing method.

[0067] The above-disclosed embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of the present invention. Therefore, any equivalent variations made in accordance with the claims of the present invention are still within the scope of the present invention.

Claims

1. A resistance brazing method for welding saw blade heads, characterized in that, include: The cutter head to be welded is placed and temporarily fixed to the welding position on the saw blade, and brazing filler metal is provided on the welding contact surface between the cutter head and the welding position; Two electrode plates electrically connected to a welding power source are provided, and the two electrode plates are respectively attached to two power contact surfaces on the cutting head that are different from the welding contact surface; The welding power supply outputs a detection power that is less than the welding power required to melt the brazing filler metal, and the contact resistance between the electrode plate and the cutting head is detected. When the contact resistance is greater than a preset resistance threshold, the power output of the welding power source is disconnected, and relative frictional movement is controlled between the electrode sheet and the power contact surface. When the frictional motion completes a preset number of times or continues for a preset duration, the welding power supply is controlled to output the detection power again, and the contact resistance is re-detected; The contact resistance detection and frictional motion are repeated in this cycle until the detected resistance is less than or equal to the resistance threshold, at which point the welding power source is controlled to output the welding power.

2. The resistance brazing method according to claim 1, characterized in that, The trajectory of the frictional motion is a uniform trajectory covering the entire power contact surface.

3. The resistance brazing method according to claim 1, characterized in that, During frictional motion, the speed and frictional pressure are kept constant.

4. The resistance brazing method according to claim 1, characterized in that, The method for detecting contact resistance includes: Multiple sets of voltage and current between the electrode plates and the cutting head are continuously collected, and the average value of the multiple sets of voltage and current is calculated using Ohm's law to obtain the contact resistance.

5. The resistance brazing method according to claim 1, characterized in that, When the number of cycles of the frictional motion reaches a preset threshold and the contact resistance is still greater than the resistance threshold, the power output of the welding power source is stopped and a shutdown instruction is issued.

6. The resistance brazing method according to claim 1, characterized in that, The welding power output process includes an initial first stage and a second stage of fusion welding; In the initial stage, the welding power source outputs a first current value for a first duration, causing the temperature of the cutting head to rise from room temperature. When the temperature of the cutting head is detected to reach 50%-80% of the melting point of the brazing filler metal, the current output by the welding power supply is switched to a second current value that is less than the first current value.

7. The resistance brazing method according to claim 6, characterized in that, During the second stage of current output, power is continuously supplied for a second duration so that the molten brazing filler metal can fully wet the welding contact surface under the action of contact pressure and surface tension.

8. A resistance brazing system for welding saw blade heads, characterized in that, The resistance welding system includes a welding power source, an electrode plate electrically connected to the welding power source, and a moving mechanism for controlling the movement of the electrode plate. The resistance welding system operates based on the resistance brazing method according to any one of claims 1 to 7.

9. A resistance brazing system, characterized in that, include: One or more processors; Memory; And one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, the programs including instructions for performing the resistance brazing method as claimed in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, Includes a computer program that can be executed by a processor to perform the resistance brazing method as described in any one of claims 1 to 7.

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