Fracture real-time detection device and method for friction stir friction welding tool

Abstract

The invention discloses a real-time fracture detection device and method for a friction stir friction welding tool, and the method comprises the steps: controlling the work of a welding structure through a central control part, recording the work data of the welding structure in real time, and analyzing and processing the work data of the welding structure according to the real-time data collected by the central control part. And judging whether the friction stir welding tool is fractured or not according to the comparison of the working data of the two time points before and after the sampling period, so that the safety and the stability of the welding process can be remarkably improved by a real-time monitoring and judging mechanism.

Description

Technical Field

[0001] The invention relates to the technical field of friction stir welding, and in particular to a real-time detection device and method for fracture of a friction stir welding tool. Background Art

[0002] Friction stir welding is a new solid-state welding method invented by the British Welding Institute (TWI) in 1991. During the welding process, the friction stir welding tool is inserted into the material to be welded. The rotating friction stir welding tool heats the welded material to a plasticized state and forms a dense joint structure under the stirring action of the friction stir welding tool to achieve the welding of the weld. Figure 1 As shown in the figure, the material in the friction stir welding process does not reach the melting point, which is solid-state welding. It has the advantages of green welding process, no need for wire addition, and small deformation after welding. It is suitable for welding light alloys, especially aluminum alloys.

[0003] Static shoulder friction stir welding is a new welding technology developed on the basis of conventional friction stir welding. During welding, the shoulder and stirring needle of the friction stir welding tool are separate structures. The shoulder does not rotate with the stirring needle, but only slides on the surface of the welded sample. Since the static shoulder does not participate in the rotational friction heat generation, the surface of the sample after welding is smooth, and there is no flash of the weld of conventional friction stir welding, which saves the subsequent flash processing process. In addition, the static shoulder does not participate in the heat generation during the welding process, only the stirring needle generates heat, which optimizes the heat input in the welding thickness direction and reduces the deformation after welding.

[0004] Double-shoulder friction stir welding is an advanced welding technology. It is based on the traditional friction stir welding (FSW) principle, but has a unique double-shoulder design, with two upper and lower shoulders and a stirring needle in the middle. During the welding process, the lower shoulder replaces the rigid support of the back of the weld in the conventional friction stir welding process, simplifying the welding tooling; at the same time, double-shoulder friction stir welding can completely solve the problem of incomplete penetration or weak connection at the root of conventional single-shoulder friction stir welding; the symmetrical distribution of the upper and lower shoulders, together, alleviates the problem of uneven heat input in the thickness direction of the weld and reduces post-weld deformation.

[0005] With the large-scale promotion and application of friction stir welding in industrial manufacturing fields such as aerospace, rail trains, shipbuilding, and new energy vehicles, some problems that need to be solved have also been exposed. With the continuous improvement of the level of automation, the demand for real-time online detection of whether the friction stir welding tool is broken during the welding process is becoming more and more urgent. Summary of the invention

[0006] The technical problem to be solved by the present invention is a real-time detection device and method for fracture of a friction stir welding tool.

[0007] To achieve the above purpose, the technical solution provided by the present invention is:

[0008] A first aspect of the present application provides a real-time detection device for fracture of a friction stir welding tool, comprising a welding structure and a central control component, wherein the central control component is used to control the operation of the welding structure and record the operation data of the welding structure in real time;

[0009] The welding structure comprises a friction stir welding tool and a driving motor for driving the friction stir welding tool to rotate, a main shaft and a tool handle, wherein the output shaft of the main shaft is used to connect with the tool handle, one end of the tool handle is a tapered structure for inserting into the center hole of the end face of the main shaft output shaft, and the other end of the tool handle is used to install the friction stir welding tool, and the tapered structure can realize automatic centering in the tool handle, thereby reducing the damage between the friction stir welding tool and the workpiece to be welded; the input shaft of the main shaft is used to connect with the driving motor, and the driving motor transmits torque to the tool handle through the main shaft;

[0010] The central control component determines whether the stir friction welding tool is broken by comparing the change rate of the welding structure working data at two time points before and after the sampling period; the central control component sends an alarm signal after determining that the stir friction welding tool is broken.

[0011] The friction stir welding tools include conventional friction stir welding tools, stationary shoulder friction stir welding tools and double shoulder friction stir welding tools.

[0012] The conventional friction stir welding tool comprises a clamping part, a shoulder and a conventional stirring pin; the clamping part is inserted into the central hole at the lower end of the tool handle and is fixed and clamped by a side top screw; the shoulder is located at the lower part of the clamping part, and its lower end surface is in close contact with the upper surface of the welded specimen during welding; the conventional stirring pin is an approximately conical structure, which is used to be inserted into the interior of the welded specimen during welding.

[0013] The stationary shoulder friction stir welding tool comprises a connecting sleeve, a stationary shoulder and a stationary shoulder stirring needle; the connecting sleeve is an approximately trapezoidal structure, the upper end face of which is in close contact with the lower end face of the main shaft and is fixed thereto by screws, and the lower end face of which is in close contact with the upper end face of the stationary shoulder and is fixed thereto by screws; the stationary shoulder is a bowl-shaped structure, the upper end face of which is connected and fastened to the lower end face of the connecting sleeve, and the center hole of the lower end face is used for the stirring needle to pass through; the upper end portion of the stationary shoulder stirring needle is inserted into the tool handle and fastened thereto, and the lower end of the stationary shoulder is passed through the center hole of the lower end portion of the stationary shoulder and penetrates into the welded sample; during welding, the lower end face of the stationary shoulder is in close contact with the upper surface of the welded specimen.

[0014] The double-shoulder friction stir welding tool comprises an upper shoulder, a lower shoulder and a double-shoulder stirring needle; the double-shoulder stirring needle is fixedly connected between the upper shoulder and the lower shoulder, a gap is provided between the upper shoulder and the lower shoulder for the workpiece to be welded to pass through, the lower end face of the upper shoulder is in close contact with the upper surface of the material to be welded, the upper end face of the lower shoulder is in close contact with the lower surface of the material to be welded, and the double-shoulder stirring needle can perform friction stir welding on the material to be welded under the drive of the upper shoulder and the lower shoulder.

[0015] The lower end surface of the shoulder of the conventional friction stir welding tool is processed with a thread, which is generally a double ring, an involute or an Archimedean curve. The thread is used to enhance the material stirring effect on the upper surface of the welded specimen to obtain a defect-free weld joint; the surface of the conventional stirring needle is processed with a right-handed thread to enhance the material flow inside the welded specimen to form a defect-free joint; the clamping part, the shoulder and the conventional stirring needle are an integral structure.

[0016] The lower end surface of the stationary shoulder of the stationary shoulder friction stir welding tool is a smooth plane. During welding, it only slides relatively on the upper surface of the welded specimen. The surface of the stationary shoulder stirring needle is processed with a right-handed thread to enhance the material flow inside the welded specimen and form an excellent joint.

[0017] The thread is processed in the hole of the lower end of the upper shoulder of the double-shoulder friction stir welding tool, which is used to cooperate with the thread on the upper part of the double-shoulder stirring needle; the center of the upper end of the lower shoulder is processed with a thread, which is used to cooperate with the thread on the lower part of the double-shoulder stirring needle, so that the stirring needle can be firmly connected between the upper shoulder and the lower shoulder, and it is easy to replace and repair; the middle part of the double-shoulder stirring needle is provided with a thread, with the center of the thickness direction of the part to be welded as the boundary, the thread is right-handed near the upper shoulder, and the thread is left-handed near the lower shoulder, and the thread is used to generate heat and plasticize the parts to be welded during welding, and drive the plasticized material to flow, so as to form an excellent weld. This structure can also increase the friction between the stirring needle and the material to be welded, and improve the welding quality.

[0018] The thread angle of the conventional stirring needle, the static shoulder stirring needle and the double shoulder stirring needle is 15° to 35°, the thread depth is 0.2 to 0.35 mm, and the welding needle length d 焊接针长 =d 板厚 -(0.2~0.3)mm to ensure that conventional stirring needles, static shoulder stirring needles and double shoulder stirring needles have sufficient strength and wear resistance.

[0019] One end of the upper shoulder of the double-shoulder friction stir welding tool is inserted into the tool handle, a key is set on the side of the upper shoulder, and a keyway is set in the tool handle. Torque is transmitted between the tool handle and the upper shoulder through the key transmission, and the upper shoulder and the tool handle can move axially.

[0020] The central control component criterion analyzes and compares the collected data. If the criterion requirements are met, it is determined that the friction stir welding tool is broken at that moment; the criterion is:

[0021] T n+2 <T n+1

[0022] Fx n+2 <Fx n+1

[0023] F n+2 <Fy n+1

[0024] F n+2 <Fz n+1

[0025] |T n+1 -T n+2 | / T n+1 ≥a%

[0026] |Fx n+1 -Fx n+2 | / Fx n+1 ≥ b%

[0027] |Fy n+1 -Fy n+2 | / Fy n+1 ≥c%

[0028] |Fz n+1 -Fz n+2 | / Fz n+1 ≥d%

[0029] |ω n+1 -ω n+2 | / ω n+1 ≤e%

[0030] |υ n+1 -υ n+2 | / υ n+1 ≤f%;

[0031] Wherein, T is the torque of the driving motor, ω is the rotation speed of the friction stir welding tool, υ is the feed speed of the friction stir welding tool, a, b, c, d, e, and f are all positive numbers greater than or equal to 0, n+1 and n+2 represent the n+1th and n+2th moments, respectively, and the n+1 and n+2 moments are the two time points before and after in a sampling period, with the n+1 moment being the first and the n+2 moment being the last; T n+2 is the driving motor torque at time n+2, T n+1 is the driving motor torque at time n+1, Fx n+2Fx is the X-direction force applied by the welding material to the friction stir welding tool at time n+2. n+1 Fy is the X-direction force applied by the welding material to the friction stir welding tool at time n+1. n+2 Fy is the Y-direction force applied by the welding material to the friction stir welding tool at time n+2. n+1 Fz is the Y-direction force applied by the welding material to the friction stir welding tool at time n+1, n+2 Fz is the Z-direction force applied by the welding material to the friction stir welding tool at time n+2. n+1 is the Z-direction force applied by the welding material to the friction stir welding tool at time n+1, T n+1 is the driving motor torque at time n+1, T n+2 is the driving motor torque at time n+2, ω n+1 is the rotation speed of the friction stir welding tool at time n+1, ω n+2 is the rotation speed of the friction stir welding tool at time n+2, υ n+1 is the feed speed of the friction stir welding tool at time n+1, υ n+2 is the feed speed of the friction stir welding tool at time n+2.

[0032] The second aspect of the present application provides a real-time detection method for the fracture of a friction stir welding tool, which controls the operation of the welding structure and records the working data of the welding structure in real time through a central control component. The working data of the welding structure is analyzed and processed based on the real-time data collected by the central control component, and a judgment is made by comparing the working data at two time points before and after the sampling period to determine whether the friction stir welding tool is broken and failed.

[0033] The real-time detection method for fracture of friction stir welding tool specifically comprises the following steps:

[0034] First, select the corresponding friction stir welding tool according to the thickness, material, welding trajectory model, etc. of the parts to be welded, and determine the D 上轴肩 , D 下轴肩 ,d 针长 , determine the rotation speed ω of the friction stir welding tool during welding, the feed speed υ of the friction stir welding tool, and the a, b, c, d, e, and f parameters in the criterion;

[0035] Next, the welding trajectory digital model of the parts to be welded is input into the central control component to generate the corresponding welding trajectory so as to perform precise trajectory control during the welding process;

[0036] Then, the welding operation is started, the friction stir welding tool is moved to the starting position of the part to be welded, and welding is performed according to the preset rotation speed ω and feed speed υ of the friction stir welding tool; during this process, the central control component collects the driving motor torque T in real time according to the set sampling period and frequency. n , Friction stir welding tool spindle rotation speed ω n , Friction stir welding tool feed speed υ n , the X-direction force Fx applied by the welding material to the friction stir welding tool n , the Y-direction force Fy applied by the welding material to the friction stir welding tool n , the Z-direction force Fz applied by the welding material to the friction stir welding tool n ;

[0037] Subsequently, the central control unit processes the collected data, including noise reduction, normalization and other steps to improve the accuracy and reliability of the data; analyzes the data in real time according to the set criteria, and determines whether the stir friction welding tool is broken by comparing the data changes at two time points before and after the sampling period;

[0038] If the criteria are met, it is determined that the friction stir welding tool is broken. At this time, the central control component sends out an alarm message, and calculates the specific location of the fracture in combination with the welding trajectory data, and displays it in real time on the interface so that the operator can take timely countermeasures;

[0039] Regardless of whether fracture occurs during the welding process, the central control component will record all key data of the welding process into the database and mark the data accordingly according to the fracture results. These data can be used for subsequent quality traceability, fault analysis and process optimization.

[0040] Compared with the prior art, the present invention has the following beneficial effects:

[0041] The present invention controls the operation of the welding structure and records the working data of the welding structure in real time through the central control component. According to the real-time data collected by the central control component, the working data of the welding structure is analyzed and processed, and a judgment is made by comparing the working data at two time points before and after the sampling period to determine whether the stir friction welding tool is broken and failed. This real-time monitoring and judgment mechanism can significantly improve the safety and stability of the welding process.

[0042] The present invention can accurately judge the fracture of the stirring tool and issue an alarm in time by setting a series of criteria (such as torque, rotation speed, and change rate of feed speed); the setting of such criteria is based on the data changes in the actual welding process and has high reliability and accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 Schematic diagram of friction stir welding process and force.

[0044] Figure 2 Schematic diagram of a conventional welding tool detection device in this embodiment.

[0045] Figure 3 Schematic diagram of the device for detecting the stationary shoulder welding tool in this embodiment.

[0046] Figure 4 Schematic diagram of the detection device of the double-shoulder welding tool in this embodiment.

[0047] Explanation of the accompanying drawings: 111 conventional welding tool, 1111 conventional welding tool stirring needle; 112 static shoulder stir friction welding tool, 1122 static shoulder, 1123 static shoulder stir friction welding tool stirring needle, 113, double shoulder welding tool; 1131, upper shoulder; 1132, lower shoulder; 1133, double shoulder welding tool stirring needle; 120, drive motor; 130, spindle; 140, tool handle; 200, central control component. DETAILED DESCRIPTION

[0048] The above contents of the present invention are further described in detail below in the form of embodiments, but this should not be understood as the scope of the above subject matter of the present invention being limited to the following embodiments, and all technologies realized based on the above contents of the present invention belong to the scope of the present invention.

[0049] The present application provides a real-time detection device for fracture of a friction stir welding tool, comprising a welding structure and a central control component, wherein the central control component is used to control the operation of the welding structure and record the operation data of the welding structure in real time;

[0050] The welding structure includes a friction stir welding tool and a driving motor, a spindle and a tool holder for driving the friction stir welding tool to rotate. The output shaft of the spindle is used to connect with the tool holder. One end of the tool holder is a tapered structure for inserting into the center hole of the end face of the spindle output shaft. The other end of the tool holder is used to install the friction stir welding tool. The tapered structure can realize automatic centering in the tool holder, reducing the damage between the friction stir welding tool and the workpiece to be welded. The input shaft of the spindle is used to connect with the driving motor, and the driving motor transmits torque to the tool holder through the spindle.

[0051] The central control component determines whether the stir friction welding tool is broken by comparing the change rate of the welding structure working data at two time points before and after the sampling period; the central control component sends an alarm signal after determining that the stir friction welding tool is broken.

[0052] The present application also provides a real-time detection method for the fracture of a friction stir welding tool, which controls the operation of the welding structure and records the working data of the welding structure in real time through a central control component. The working data of the welding structure is analyzed and processed based on the real-time data collected by the central control component, and a judgment is made by comparing the working data at two time points before and after the sampling period to determine whether the friction stir welding tool is broken and failed.

[0053] This application also provides criteria for determining the central control component, including:

[0054] T n+2 <T n+1

[0055] Fx n+2 <Fx n+1

[0056] F n+2 <Fy n+1

[0057] F n+2 <Fz n+1

[0058] |T n+1 -T n+2 | / T n+1 ≥a%

[0059] |Fx n+1 -Fx n+2 | / Fx n+1 ≥ b%

[0060] |Fy n+1 -Fy n+2 | / Fy n+1 ≥c%

[0061] |Fz n+1 -Fz n+2 | / Fz n+1 ≥d%

[0062] |ω n+1 -ω n+2 | / ω n+1 ≤e%

[0063] |υ n+1 -υ n+2 | / υ n+1 ≤f%;

[0064] Where: T is the torque of the driving motor, ω is the rotation speed of the friction stir welding tool, υ is the feed speed of the friction stir welding tool, a, b, c, d, e, f are all positive numbers greater than or equal to 0, n+1 and n+2 represent the n+1th and n+2th moments respectively, and the n+1 and n+2 moments are the two time points before and after in a sampling period, with the n+1 moment being the first and the n+2 moment being the last; T n+2 is the driving motor torque at time n+2, T n+1 is the driving motor torque at time n+1, Fx n+2 Fx is the X-direction force applied by the welding material to the friction stir welding tool at time n+2. n+1 Fy is the X-direction force applied by the welding material to the friction stir welding tool at time n+1. n+2 Fy is the Y-direction force applied by the welding material to the friction stir welding tool at time n+2. n+1 Fz is the Y-direction force applied by the welding material to the friction stir welding tool at time n+1, n+2 Fz is the Z-direction force applied by the welding material to the friction stir welding tool at time n+2. n+1 is the Z-direction force applied by the welding material to the friction stir welding tool at time n+1, T n+1 is the driving motor torque at time n+1, T n+2 is the driving motor torque at time n+2, ω n+1 is the rotation speed of the friction stir welding tool at time n+1, ω n+2 is the rotation speed of the friction stir welding tool at time n+2, υ n+1 is the feed speed of the friction stir welding tool at time n+1, υ n+2 is the feed speed of the friction stir welding tool at time n+2.

[0065] Different criteria may be selected for use in combination for different application scenarios, which will be illustrated below in the form of embodiments.

[0066] Friction stir welding is a process of force-heat coupling. The external execution structure (drive motor) applies torque to the friction stir welding tool to rotate and feed at a set speed. The friction stir welding tool overcomes the reaction force (Z-direction resistance, X-direction resistance and Y-direction resistance) applied by the welded material, and drives the welded material to move in the X, Y and Z directions along with the friction stir welding tool, thereby forming a weld. During the welding process, the friction stir welding tool is the only one that contacts and interacts with the welded material. The friction stir welding tool is subjected to the force applied to the friction stir welding tool by the welding material Fx, Fy and Fz from the X, Y and Z directions respectively. At the same time, in order to execute the program according to the set rotation speed and feed speed, the friction stir welding tool is also subjected to the torque T transmitted by the external motor, thereby overcoming the forces of Fx, Fy and Fz to achieve a balanced state.

[0067] The magnitude of the forces Fx, Fy and Fz exerted on the friction stir welding tool is closely related to the welded material, welding thickness and welding process parameters. When the welding material and thickness remain unchanged, changes in welding parameters will also affect the magnitude of the above forces. For example, when the rotation speed increases, the welding temperature increases, the material will soften, and then Fx, Fy and Fz will decrease; and when the feed speed increases, the heat input per unit length will decrease, the welding temperature response will decrease, and the material will become harder, then Fx, Fy and Fz will increase.

[0068] When the friction stir welding tool breaks, the volume of its driving material will be greatly reduced, so its Fx, Fy and Fz forces will be reduced. In order to maintain the set rotation speed and feed speed, the external input torque will also be reduced, thus reaching a new balance.

[0069] In this article, the breakage of the friction stir welding tool refers to the separation of the stirring needle from the shoulder. Generally, in a normal welding process, the material driven by the stirring needle accounts for 70-80% of the material driven by the friction stir welding tool. If the stirring needle separates from the shoulder, the volume of the material driven by the friction stir welding tool will be reduced by 70-80% accordingly, and the forces Fx, Fy and Fz will undergo a certain value mutation.

[0070] This mutation value can be used to determine whether the stirring needle is broken or detached from the shoulder during the welding process.

[0071] For stationary shoulder friction stir welding, the volume of the material driven by the stirring needle accounts for 95% or more of the volume of the material driven by the entire friction stir welding tool. If the stirring needle is detached from the shoulder, the volume of the material driven by the friction stir welding tool will be reduced by 95% or more accordingly, and the forces Fx, Fy and Fz will undergo a certain numerical mutation.

[0072] During the double-shoulder friction stir welding process, the Z-direction force is offset to 0 by the upper and lower shoulders. During normal welding, the material driven by the stirring needle accounts for 60-70% of the material driven by the friction stir welding tool. If the stirring needle is detached from the shoulder, the volume of the material driven by the friction stir welding tool will be reduced by 60-70% accordingly, and the Fx and Fy forces will undergo a certain value mutation.

[0073] In some embodiments, a conventional friction stir welding tool includes a clamping portion, a shoulder and a conventional stirring pin; the clamping portion is inserted into the center hole at the lower end of the tool handle and is fixed and clamped by a side top screw; the shoulder is located at the lower part of the clamping portion, and its lower end surface is in close contact with the upper surface of the welded specimen during welding; the conventional stirring pin is a conical structure, which is inserted into the interior of the welded specimen during welding.

[0074] In some embodiments, the stationary shoulder friction stir welding tool includes a connecting sleeve, a stationary shoulder and a stationary shoulder stirring needle; the connecting sleeve is a trapezoidal structure, whose upper end face is in close contact with the lower end face of the main shaft and is fixed thereto by screws, and whose lower end face is in close contact with the upper end face of the stationary shoulder and is fixed thereto by screws; the stationary shoulder is a bowl-shaped structure, whose upper end face is connected and fastened to the lower end face of the connecting sleeve, and the center hole of its lower end face is used for the stirring needle to pass through; the upper end of the stationary shoulder stirring needle is inserted into the tool handle and fastened to the tool handle, and its lower end passes through the center hole of the lower end of the stationary shoulder and penetrates into the welded sample; during welding, the lower end face of the stationary shoulder is in close contact with the upper surface of the welded specimen.

[0075] In some embodiments, a double-shoulder friction stir welding tool includes an upper shoulder, a lower shoulder and a double-shoulder stirring needle; the double-shoulder stirring needle is fixedly connected between the upper shoulder and the lower shoulder, and a gap is provided between the upper shoulder and the lower shoulder for the workpiece to be welded to pass through, the lower end face of the upper shoulder is in close contact with the upper surface of the material to be welded, and the upper end face of the lower shoulder is in close contact with the lower surface of the material to be welded, and the double-shoulder stirring needle can perform friction stir welding on the material to be welded under the drive of the upper shoulder and the lower shoulder.

[0076] In some embodiments, a thread is machined on the lower end surface of the shoulder of a conventional friction stir welding tool, which is generally a double circular ring, an involute or an Archimedean curve, and the thread is used to enhance the material stirring effect on the upper surface of the welded specimen to obtain a defect-free weld joint; the surface of the conventional stirring needle is machined with a right-handed thread to enhance the material flow inside the welded specimen to form a defect-free joint; the clamping part, the shoulder and the conventional stirring needle are an integral structure.

[0077] In some embodiments, the lower end surface of the stationary shoulder of the stationary shoulder friction stir welding tool is a smooth plane, and during welding, it only slides relative to the upper surface of the welded specimen. The surface of the stationary shoulder stirring needle is processed with a right-handed thread to enhance the material flow inside the welded specimen and form an excellent joint.

[0078] In some embodiments, the hole at the lower end of the upper shoulder of the double-shoulder friction stir welding tool is processed with threads for matching with the threads at the upper part of the double-shoulder stirring needle; the center of the upper end of the lower shoulder is processed with threads for matching with the threads at the lower part of the double-shoulder stirring needle, so that the stirring needle can be firmly connected between the upper shoulder and the lower shoulder, and is easy to replace and repair; the middle part of the double-shoulder stirring needle is provided with threads, with the center of the thickness direction of the part to be welded as the boundary, the threads are right-handed near the upper shoulder and left-handed near the lower shoulder, and the threads are used to generate heat and plasticize the parts to be welded by friction during welding, and drive the plasticized material to flow, thereby forming an excellent weld. This structure can also increase the friction between the stirring needle and the material to be welded, and improve the welding quality.

[0079] Preferably, in some embodiments, the thread angle of the conventional stirring needle, the static shoulder stirring needle and the double shoulder stirring needle is 15° to 35°, the thread depth is 0.2 to 0.35 mm, and the welding needle length d is 焊接针长 =d 板厚 -(0.2~0.3)mm to ensure that conventional stirring needles, static shoulder stirring needles and double shoulder stirring needles have sufficient strength and wear resistance.

[0080] One end of the upper shoulder of the double-shoulder friction stir welding tool is inserted into the tool handle, a key is set on the side of the upper shoulder, and a keyway is set in the tool handle. Torque is transmitted between the tool handle and the upper shoulder through the key transmission, and the upper shoulder and the tool handle can move axially.

[0081] The present invention is further described in detail below in conjunction with specific embodiments:

[0082] Example 1

[0083] The following combination Figure 1 To further explain this application in detail,

[0084] The present application discloses a conventional stir friction welding tool fracture real-time detection device, referring to Figure 1 .

[0085] The implementation steps are:

[0086] S1: Select the corresponding conventional friction stir welding tool according to the thickness, material, welding trajectory model, etc. of the parts to be welded, and determine D 轴肩 , d 针长, determine the rotation speed ω, feed speed υ, and parameters a, b, c, d, e, f, etc. in the criterion. Take a 15-meter-long, 1000-mm-wide, 6-mm-thick 5083 aluminum alloy extruded profile long straight weld as an example. The selected stirring tool shoulder diameter D 轴肩 = 18 mm, the length d of the conventional welding tool stirring needle 1111 针长 =5.8mm, feed speed υ during stable welding =300mm / min, rotation speed ω =800rpm; criteria a = 30, b = 30, c = 30, d = 30, e = 2, f = 2.

[0087] S2: Input the welding trajectory digital model of the parts to be welded into the central control computer to generate the corresponding welding trajectory.

[0088] S3: Input the parameters selected in step S1 into the central control computer, and input parameters a, b, c, d, e, f and the like into the determination software.

[0089] S4: Fix the parts to be welded and determine the starting and ending positions of welding;

[0090] S5: Welding starts, the conventional welding tool 111 enters the part to be welded just above the part to be welded, and welds according to the set rotation speed ω, feed speed υ and welding direction. In this embodiment, the rotation speed ω is 800 rpm; the feed speed υ is 300 mm / min.

[0091] S6: The central control machine collects the motor torque Tn, spindle rotation speed ωn, feed speed υn and other data at time tn according to the sampling period and frequency, and sends the above data to the judgment software.

[0092] S7: After receiving the data sent by the central control machine in S6, the judgment software performs noise reduction and normalization processing on the data, and analyzes and compares the collected data according to the judgment criteria. If the requirements of the judgment criteria are met, it is determined that the mixing tool is broken at this moment, and the alarm information is sent to the central control machine;

[0093] The specific criteria are:

[0094] T n+2 <T n+1

[0095] |T n+1 -T n+2 | / T n+1 ≥a%

[0096] |Fx n+1 -Fx n+2 | / Fx n+1 ≥ b%

[0097] |Fyn+1 -Fy n+2 | / Fy n+1 ≥c%

[0098] |Fz n+1 -Fz n+2 | / Fz n+1 ≥d%

[0099] |ω n+1 -ω n+2 | / ω n+1 ≤e%

[0100] |υ n+1 -υ n+2 | / υ n+1 ≤f%;

[0101] For example, T 18.24 >T 18.22 , and |T 18.24 -T 18.22 | / T 18.22 ≥30%,|Fx 18.22 -Fx 18.24 | / Fx 18.22 ≥30%

[0102] |Fy 18.22 -Fy 18.24 | / Fy 18.22 ≥30%,|Fz 18.22 -Fz 18.24 | / Fz 18.22 ≥30%,|ω 18.24 -ω 18.22 | / ω 18.22 ≤2%,|υ 18.24 -υ 18.22 | / υ 18.22 ≤2%; then determine at t 18.24 At this moment, the stirring tool broke; if the above criteria are not met, then continue to collect and analyze data.

[0103] S8: After receiving the alarm information from the judgment software, the central control computer calculates the location of the fracture based on the welding trajectory, and presents the location information on the interface to remind the operator to handle it.

[0104] S9: If the fracture result is true, then record the above parameters into the database and mark the data. If the fracture result is false, then also record the above parameters into the database and mark the data accordingly. As the amount of data increases, the accuracy of the judgment increases.

[0105] Example 2

[0106] The following combination Figure 2 To further explain this application in detail,

[0107] The present application discloses a device for detecting the fracture of a static shoulder friction stir welding tool in real time. Figure 2 .

[0108] The implementation steps are:

[0109] S1: Select the corresponding static shoulder friction stir welding tool 112 according to the thickness, material, welding trajectory digital model, etc. of the parts to be welded, and determine the center hole diameter D of the static shoulder friction stir welding tool 112 中心孔 , outer diameter D 外径 , d 针长 , determine the rotation speed ω, feed speed υ, and parameters a, b, c, d, e, f, etc. in the criterion. Take a 15-meter-long, 1000-mm-wide, 6-mm-thick 5083 aluminum alloy extruded profile long straight weld as an example. The center hole diameter D of the static shoulder friction stir welding tool 112 is selected. 中心孔 =6.5mm, outer diameter D 外径 =14.5mm, the length d of the static shoulder friction stir welding tool stirring needle 1123 针长 =5.8mm, feed speed υ during stable welding =350mm / min, rotation speed ω =1200rpm; criteria a = 15, b = 15, c = 15, d = 15, e = 2, f = 2.

[0110] S2: Input the welding trajectory digital model of the parts to be welded into the central control computer to generate the corresponding welding trajectory.

[0111] S3: Input the parameters selected in step S1 into the central control computer, and input parameters a, b, c, d, e, f and the like into the determination software.

[0112] S4: Fix the parts to be welded and determine the starting and ending positions of welding;

[0113] S5: Welding starts, the stationary shoulder welding tool 112 enters the part to be welded just above the part to be welded, and welds according to the set rotation speed ω, feed speed υ and welding direction. In this embodiment, the rotation speed ω is 1200 rpm; the feed speed υ is 350 mm / min.

[0114] S6: The central control machine collects the motor torque Tn, spindle rotation speed ωn, feed speed υn and other data at time tn according to the sampling period and frequency, and sends the above data to the judgment software.

[0115] S7: After receiving the data sent by the central control machine in S6, the judgment software performs noise reduction and normalization processing on the data, and analyzes and compares the collected data according to the judgment criteria. If the requirements of the judgment criteria are met, it is determined that the mixing tool is broken at this moment, and the alarm information is sent to the central control machine;

[0116] The specific criteria are:

[0117] T n+2 <T n+1

[0118] |T n+1 -T n+2 | / T n+1 ≥a%

[0119] |Fx n+1 -Fx n+2 | / Fx n+1 ≥ b%

[0120] |Fy n+1 -Fy n+2 | / Fy n+1 ≥c%

[0121] |Fz n+1 -Fz n+2 | / Fz n+1 ≥d%

[0122] |ω n+1 -ω n+2 | / ω n+1 ≤e%

[0123] |υ n+1 -υ n+2 | / υ n+1 ≤f%;

[0124] For example, T 18.24 >T 18.22 , and |T 18.24 -T 18.22 | / T 18.22 ≥15%,|Fx 18.22 -Fx 18.24 | / Fx 18.22 ≥15%

[0125] |Fy 18.22 -Fy 18.24 | / Fy 18.22 ≥15%,|Fz 18.22 -Fz 18.24 | / Fz 18.22 ≥15%,|ω 18.24 -ω 18.22 | / ω 18.22 ≤2%,|υ18.24 -υ 18.22 | / υ 18.22 ≤2%; then determine at t 18.24 At this moment, the stirring tool broke; if the above criteria are not met, then continue to collect and analyze data.

[0126] S8: After receiving the alarm information from the judgment software, the central control computer calculates the location of the fracture based on the welding trajectory, and presents the location information on the interface to remind the operator to handle it.

[0127] S9: If the fracture result is true, then record the above parameters into the database and mark the data. If the fracture result is false, then also record the above parameters into the database and mark the data accordingly. As the amount of data increases, the accuracy of the judgment increases.

[0128] Example 3

[0129] The following is combined with Figure 3 and 4 This application is described in further detail.

[0130] The present application discloses a dual-shoulder friction stir welding tool fracture real-time detection device, which includes a welding structure for welding a workpiece to be welded, and a central control component 200 for controlling the operation of the welding structure and for real-time recording the operation data of the welding structure.

[0131] Reference Figure 3 The welding structure includes a double-shoulder welding tool 113, a driving motor 120 for driving the double-shoulder welding tool 113 to rotate, and a driving member for transmitting the torque of the driving motor 120 to the double-shoulder welding tool 113. The speed of the driving motor 120 is 100-10000rpm, the power is 14-50KW, the rated speed is 1500rpm, and the torque is 10-100Nm. The driving motor 120 transmits the torque to the double-shoulder welding tool 113 through the driving member, thereby driving the double-shoulder welding tool 113 to work.

[0132] Reference Figure 4 The double-shoulder welding tool 113 in this embodiment is a floating double-shoulder welding tool, and its specific structure is as follows: the double-shoulder welding tool 113 includes an upper shoulder 1131 ; a lower shoulder 1132 ; and a double-shoulder welding tool stirring needle 1133 .

[0133] The stirring needle 1133 of the double-shoulder welding tool is fixedly connected between the upper shoulder 1131 and the lower shoulder 1132. A gap is provided between the upper shoulder 1131 and the lower shoulder 1132 for the workpiece to be welded to pass through. The lower end surface of the upper shoulder 1131 is in close contact with the upper surface of the material to be welded, and the upper end surface of the lower shoulder 1132 is in close contact with the lower surface of the material to be welded. The diameter D of the upper shoulder 1131 is 上轴肩 and the diameter D of the lower shoulder 1132 下轴肩 Can be the same or different, generally, D 上轴肩 =D 下轴肩 ≈(2.5~3)d 板厚 ;

[0134] In this implementation, the parts to be welded are long straight extruded profiles or plate parts. During welding, the double-shoulder friction stir welding tool enters from the side to start welding, and then leaves the part from the other side after completion, so that the upper and lower surfaces of the parts to be welded are welded at the same time. The feed speed during welding is generally 100-3000mm / min.

[0135] The upper, middle and lower parts of the stirring pin 1133 are all processed with threads. The upper thread is inserted into the hole on the lower end face of the upper shoulder 1131, and the lower thread is inserted into the hole on the upper end face of the lower shoulder 1132. The hole at the lower end of the upper shoulder 1131 is processed with threads for matching with the threads on the upper part of the stirring pin 1133; the center of the upper end of the lower shoulder 1132 is processed with threads for matching with the threads on the lower part of the stirring pin 1133. The threads in the middle of the stirring pin 1133 are used to generate heat and plasticize the parts to be welded by friction during welding, and drive the plasticized material to flow, thereby forming an excellent weld. In order to further improve the welding quality, the threads in the middle of the stirring pin 1133 are bounded by the center of the thickness direction of the parts to be welded, with right-hand threads near the upper shoulder 1131 and left-hand threads near the lower shoulder 1132. The inclination angle of the threads of the stirring pin 1133 is 15° to 35°, the thread depth is 0.2-0.35mm, and the welding pin length d 焊接针长 =d 板厚 -(0.2~0.3)mm. The setting of these parameters can ensure that the stirring needle 1133 has sufficient strength and wear resistance. The material of the floating double-shoulder friction stir welding tool is generally H13 mold steel, high-speed steel, etc., or MP159 or tungsten-rhenium alloy.

[0136] Reference Figure 3 The driving member includes a main shaft 130 , an output shaft of which is used to connect with a welding tool, and an input shaft of the main shaft 130 is used to connect with a driving motor 120 , and the driving motor 120 transmits torque to the welding tool through the main shaft 130 .

[0137] The driving member also includes a tool handle 140, one end of which is a conical structure for inserting into the center hole of the output shaft end face of the main shaft 130, and can realize automatic centering in the tool handle 140. The other end of the tool handle 140 is used to install a double-shoulder friction stir welding tool, and the specific structure is as follows: a keyway is arranged in the tool handle 140. One end of the upper shoulder 1131 is inserted into the tool handle 140, and a key is arranged on the side of the upper shoulder 1131. Torque is transmitted between the tool handle 140 and the upper shoulder 1131 through key transmission, and the upper shoulder 1131 and the tool handle 140 can move axially. The key connection is used to transmit torque to the floating double-shoulder friction stir welding tool installed thereon, and the floating double-shoulder friction stir welding tool and the keyway are floated up and down. The floating double shoulder can dynamically adjust the height position of the stirring tool according to the thickness of the target part, which is suitable for welding large-size extruded profiles.

[0138] The central control component 200 includes a data acquisition module for reading real-time data from sensors and converting them into digital signals for subsequent processing. The sensors are torque sensors installed in the welding structure for high-precision detection of the torque of the drive motor 120, speed sensors for detecting the speed of the drive motor 120, and speed sensors for testing the feeding speed of the welding tool. The rotation speed of the stirring tool is calculated by the transmission ratio of the drive motor 120.

[0139] The central control unit 200 also includes a data processing module for receiving and processing real-time data from the data acquisition module. The module collects the change rates of torque, rotation speed and feed speed at two time points (n+1 and n+2) before and after the sampling period. It makes a judgment based on a preset criterion. Generally, the sampling period is 0.02s and the judgment time is 0.01s.

[0140] The specific criteria are:

[0141] T n+2 <T n+1

[0142] Fx n+2 <Fx n+1

[0143] F n+2 <Fy n+1

[0144] |T n+1 -T n+2 | / T n+1 ≥a%

[0145] |Fx n+1 -Fx n+2 | / Fx n+1 ≥ b%

[0146] |Fy n+1-Fy n+2 | / Fy n+1 ≥c%

[0147] |ω n+1 -ω n+2 | / ω n+1 ≤e%

[0148] |υ n+1 -υ n+2 | / υ n+1 ≤f%;

[0149] Among them, a, b, c, e, and f are thresholds set according to actual application scenarios, and a, b, c, e, and f are all positive numbers greater than or equal to 0.

[0150] The hollow component 200 also includes an alarm module. When the data processing module determines that the stirring tool is broken according to the criterion, the alarm module will be triggered, and the alarm information will be displayed on the hollow platform to remind the operator to pay attention to the information.

[0151] In this embodiment, the control system is developed using Windows software, which is compatible with Siemens control systems, Beckhoff control systems, and multiple independently developed software, and has an HMI interface. The torque T spindle motor, rotation speed ω, feed speed υ, welding time and other data of the spindle drive motor 120 can be collected at a certain interval Δt, and the welding trajectory information can be automatically generated by inputting the 3D model or AUTOCAD model of the welding trajectory in advance. The welding trajectory information is used by the operator to quickly find the fracture position of the tool.

[0152] The present application discloses a method for real-time detection of fracture of a dual-shoulder friction stir welding tool, comprising the following steps:

[0153] S1: Select the corresponding floating double-shoulder friction stir welding tool according to the thickness, material, welding trajectory model, etc. of the parts to be welded, and determine D 上轴肩 , D 下轴肩 , d 针长 , determine the rotation speed ω, feed speed υ, and parameters a, b and c in the criterion during welding. Take a 15-meter-long, 1000-mm-wide, 6-mm-thick 5083 aluminum alloy extruded profile long straight weld as an example. The selected upper shoulder 111 diameter D of the stirring tool 上轴肩 =16mm, lower shoulder 112 diameter D 下轴肩 =16mm, the length d of the stirring needle 113 针长 =5.8mm, feed speed υ during stable welding =400mm / min, rotation speed ω =500rpm; criteria a = 40, b = 40, c = 40, e = 2, f = 2.

[0154] S2: Input the welding trajectory digital model of the parts to be welded into the central control computer to generate the corresponding welding trajectory.

[0155] S3: Input the parameters selected in step S1 into the central control computer, and input parameters a, b, c, e, f and the like into the determination software.

[0156] S4: Fix the parts to be welded and determine the starting and ending positions of welding;

[0157] S5: Welding starts, the floating double-shoulder welding tool 113 enters the part to be welded from the side of the part to be welded, and welds according to the set rotation speed ω, feed speed υ and welding direction. In this embodiment, the rotation speed ω is 500 rpm; the feed speed υ is 400 mm / min.

[0158] S6: The central control machine collects the motor torque Tn, spindle rotation speed ωn, feed speed υn and other data at time tn according to the sampling period and frequency, and sends the above data to the judgment software.

[0159] S7: After receiving the data sent by the central control machine in S6, the judgment software performs noise reduction and normalization processing on the data, and analyzes and compares the collected data according to the judgment criteria. If the requirements of the judgment criteria are met, it is determined that the mixing tool is broken at this moment, and the alarm information is sent to the central control machine;

[0160] The specific criteria are:

[0161] T n+2 <T n+1

[0162] Fx n+2 <Fx n+1

[0163] F n+2 <Fy n+1

[0164] |T n+1 -T n+2 | / T n+1 ≥a%

[0165] |Fx n+1 -Fx n+2 | / Fx n+1 ≥ b%

[0166] |Fy n+1 -Fy n+2 | / Fy n+1 ≥c%

[0167] |ω n+1 -ω n+2 | / ω n+1≤e%

[0168] |υ n+1 -υ n+2 | / υ n+1 ≤f%;

[0169] For example, T 18.24 >T 18.22 , and |T 18.22 -T 18.24 | / T 18.22 ≥40%,|Fx 18.22 -Fx 18.24 | / Fx 18.22 ≥40%

[0170] |Fy 18.22 -Fy 18.24 | / Fy 18.22 ≥40%,|ω 18.22 -ω 18.24 | / ω 18.22 ≤2%,|υ 18.22 -υ 18.24 | / υ 18.22 ≤2%; then determine at t 18.24 At this moment, the stirring tool broke; if the above criteria are not met, then continue to collect and analyze data.

[0171] S8: After receiving the alarm information from the judgment software, the central control computer calculates the location of the fracture based on the welding trajectory, and presents the location information on the interface to remind the operator to handle it.

[0172] S9: If the fracture result is true, then record the above parameters into the database and mark the data. If the fracture result is false, then also record the above parameters into the database and mark the data accordingly. As the amount of data increases, the accuracy of the judgment increases.

[0173] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any technician familiar with the profession, without departing from the scope of the technical solution of the present invention, according to the technical essence of the present invention, any simple modification, equivalent replacement and improvement made to the above embodiment still falls within the protection scope of the technical solution of the present invention.

Claims

1. A real-time detection device for fracture of friction stir welding tools, characterized in that: It includes a welding structure and a central control component, wherein the central control component is used to control the operation of the welding structure and record the working data of the welding structure in real time; The welding structure comprises a friction stir welding tool and a driving motor, a spindle and a tool handle for driving the friction stir welding tool to rotate. The output shaft of the spindle is used to connect with the tool handle. One end of the tool handle is a conical structure for inserting into the center hole of the end face of the spindle output shaft. The other end of the tool handle is used to install the friction stir welding tool. The input shaft of the spindle is used to connect with the driving motor. The driving motor transmits torque to the tool handle through the spindle. The central control component determines whether the stir friction welding tool is broken by comparing the change rate of the welding structure working data at two time points before and after the sampling period; the central control component sends an alarm signal after determining that the stir friction welding tool is broken.

2. The real-time detection device for fracture of friction stir welding tools according to claim 1 is characterized in that: The friction stir welding tools include conventional friction stir welding tools, stationary shoulder friction stir welding tools and double shoulder friction stir welding tools.

3. The real-time detection device for fracture of friction stir welding tools according to claim 2 is characterized in that: The conventional friction stir welding tool comprises a clamping part, a shoulder and a conventional stirring pin; the clamping part is inserted into the central hole at the lower end of the tool handle and is fixed and clamped by a side top screw; the shoulder is located at the lower part of the clamping part, and its lower end surface is in close contact with the upper surface of the welded specimen during welding; the conventional stirring pin is a conical structure, which is used to be inserted into the interior of the welded specimen during welding.

4. The real-time detection device for fracture of friction stir welding tools according to claim 2 is characterized in that: The stationary shoulder friction stir welding tool comprises a connecting sleeve, a stationary shoulder and a stationary shoulder stirring needle; the connecting sleeve is a trapezoidal structure, the upper end face of which is in close contact with the lower end face of the main shaft and is fixed thereto by screws, and the lower end face of which is in close contact with the upper end face of the stationary shoulder and is fixed thereto by screws; the stationary shoulder is a bowl-shaped structure, the upper end face of which is connected and fastened to the lower end face of the connecting sleeve, and the center hole of the lower end face is used for the stirring needle to pass through; the upper end portion of the stationary shoulder stirring needle is inserted into the tool handle and fastened thereto, and the lower end of the stationary shoulder stirring needle passes through the center hole of the lower end portion of the stationary shoulder and is inserted into the welded sample; during welding, the lower end face of the stationary shoulder is in close contact with the upper surface of the welded specimen.

5. The real-time detection device for fracture of friction stir welding tools according to claim 2 is characterized in that: The double-shoulder friction stir welding tool comprises an upper shoulder, a lower shoulder and a double-shoulder stirring needle; the double-shoulder stirring needle is fixedly connected between the upper shoulder and the lower shoulder, a gap is provided between the upper shoulder and the lower shoulder for the workpiece to be welded to pass through, the lower end face of the upper shoulder is in close contact with the upper surface of the material to be welded, the upper end face of the lower shoulder is in close contact with the lower surface of the material to be welded, and the double-shoulder stirring needle can perform friction stir welding on the material to be welded under the drive of the upper shoulder and the lower shoulder.

6. The real-time detection device for fracture of friction stir welding tools according to claim 3 is characterized in that: The lower end surface of the shoulder of the conventional friction stir welding tool is processed with a thread, and the thread is used to enhance the material stirring effect on the upper surface of the welded specimen to obtain a defect-free weld joint; the surface of the conventional stirring needle is processed with a right-handed thread to enhance the material flow inside the welded specimen to form a defect-free joint; the clamping part, the shoulder and the conventional stirring needle are an integral structure.

7. The real-time detection device for fracture of friction stir welding tools according to claim 4 is characterized in that: The lower end surface of the stationary shoulder of the stationary shoulder friction stir welding tool is a smooth plane. During welding, it only slides relative to the upper surface of the welded specimen. The surface of the stationary shoulder stirring needle is processed with a right-handed thread to enhance the material flow inside the welded specimen.

8. The real-time detection device for fracture of friction stir welding tools according to claim 5, characterized in that: The thread is processed in the hole of the lower end of the upper shoulder of the double-shoulder friction stir welding tool, which is used to cooperate with the thread on the upper part of the double-shoulder stirring needle; the center of the upper end of the lower shoulder is processed with a thread, which is used to cooperate with the thread on the lower part of the double-shoulder stirring needle, so that the stirring needle can be firmly connected between the upper shoulder and the lower shoulder; the middle part of the double-shoulder stirring needle is provided with a thread, which is bounded by the center of the thickness direction of the part to be welded, the thread is right-handed near the upper shoulder, and the thread is left-handed near the lower shoulder. The thread is used to generate heat and plasticize the parts to be welded by friction during welding, and drive the plasticized material to flow, thereby forming an excellent weld. This structure can also increase the friction between the stirring needle and the material to be welded, and improve the welding quality.

9. The real-time detection device for fracture of a friction stir welding tool according to claim 6, 7 or 8, characterized in that: The thread angle of the conventional stirring needle, the static shoulder stirring needle and the double shoulder stirring needle is 15° to 35°, the thread depth is 0.2 to 0.35 mm, and the welding needle length d 焊接针长 =d 板厚 -(0.2~0.3)mm.

10. The real-time detection device for fracture of friction stir welding tools according to claim 5 or 8, characterized in that: One end of the upper shoulder of the double-shoulder friction stir welding tool is inserted into the tool handle, a key is set on the side of the upper shoulder, and a keyway is set in the tool handle. Torque is transmitted between the tool handle and the upper shoulder through the key transmission, and the upper shoulder and the tool handle can move axially.

11. The real-time detection device for fracture of friction stir welding tools according to claim 1, characterized in that: The central control component analyzes and compares the collected data. If the criteria are met, it is determined that the friction stir welding tool is broken at that moment. The criteria include: T n+2 <T n+1 Fx n+2 <Fx n+1 My n+2 <Fy n+1 Fz n+2 <Fz n+1 |T n+1 -T n+2 | / T n+1 ≥a% |Fx n+1 -Fx n+2 | / Fx n+1 ≥b% |My n+1 -My n+2 | / My n+1 ≥c% |Fz n+1 -Fz n+2 | / Fz n+1 ≥d% |oh n+1 -oh n+2 | / h n+1 ≤e% |u n+1 -u n+2 | / u n+1 ≤f%; in: T is the torque of the driving motor, ω is the rotation speed of the friction stir welding tool, υ is the feed speed of the friction stir welding tool, a, b, c, d, e, f are all positive numbers greater than or equal to 0, n+1 and n+2 represent the n+1th and n+2th moments respectively, The n+1 and n+2 moments are two time points in a sampling period, namely, the n+1 moment is in front and the n+2 moment is in the back. n+2 is the driving motor torque at time n+2, T n+1 is the driving motor torque at time n+1, Fx n+2 Fx is the X-direction force applied by the welding material to the friction stir welding tool at time n+2. n+1 Fy is the X-direction force applied by the welding material to the friction stir welding tool at time n+1. n+2 Fy is the Y-direction force applied by the welding material to the friction stir welding tool at time n+2. n+1 Fz is the Y-direction force applied by the welding material to the friction stir welding tool at time n+1, n+2 Fz is the Z-direction force applied by the welding material to the friction stir welding tool at time n+2. n+1 is the Z-direction force applied by the welding material to the friction stir welding tool at time n+1, T n+1 is the driving motor torque at time n+1, T n+2 is the driving motor torque at time n+2, ω n+1 is the rotation speed of the friction stir welding tool at time n+1, ω n+2 is the rotation speed of the friction stir welding tool at time n+2, υ n+1 is the feed speed of the friction stir welding tool at time n+1, υ n+2 is the feed speed of the friction stir welding tool at time n+2.

12. A real-time detection method for fracture of a friction stir welding tool, characterized in that: The operation of the welding structure is controlled by the central control component and the working data of the welding structure is recorded in real time. The working data of the welding structure is analyzed and processed according to the real-time data collected by the central control component. The working data at two time points before and after the sampling period are compared to determine whether the stir friction welding tool is broken and failed.

13. A real-time detection method for fracture of a friction stir welding tool, characterized in that: The friction stir welding tool fracture real-time detection device according to claim 11 comprises the following steps: firstly, selecting a corresponding friction stir welding tool according to the thickness, material, welding trajectory digital model, etc. of the parts to be welded, determining D 上轴肩 , D 下轴肩 d 针长 , determine the rotation speed ω of the friction stir welding tool, the feed speed υ of the friction stir welding tool, and the a, b, c, d, e, and f parameters in the criterion during welding; then, input the welding trajectory digital model of the parts to be welded into the central control component to generate the corresponding welding trajectory so as to perform precise trajectory control during the welding process; then, start the welding operation, move the friction stir welding tool to the starting position of the parts to be welded, and weld according to the preset rotation speed ω of the friction stir welding tool and the feed speed υ of the friction stir welding tool; in this process, the central control component collects the driving motor torque T in real time according to the set sampling period and frequency n , Friction stir welding tool spindle rotation speed ω n , Friction stir welding tool feed speed υ n , the X-direction force Fx applied by the welding material to the friction stir welding tool n , the Y-direction force Fy applied by the welding material to the friction stir welding tool n , the Z-direction force Fz applied by the welding material to the friction stir welding tool n ; Then, the central control component performs noise reduction and normalization operations on the collected data to improve the accuracy and reliability of the data; the data is analyzed in real time according to the set criteria, and by comparing the data changes at the two time points before and after the sampling period, it is determined whether the stir friction welding tool is broken; If the requirements of the judgment criteria are met, that is, it is determined that the stir friction welding tool is broken, the central control component will issue an alarm message, and calculate the specific location of the fracture in combination with the welding trajectory data, and display it in real time on the interface so that the operator can take timely response measures; regardless of whether fracture occurs during the welding process, the central control component will record all key data of the welding process in the database, and mark the data accordingly according to the fracture results.

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