Method, device, equipment and medium for regulating temperature field of middleware rotation friction welding

Abstract

The present application discloses a method, device, equipment and medium for controlling the temperature field of middlepiece rotation friction welding, which belongs to the field of friction welding technology. The method includes: after the middlepiece is driven by a motor to rotate continuously to a preset speed, the first workpiece to be welded and the second workpiece to be welded are driven by a hydraulic system to move toward the middlepiece and apply friction pressure, and start timing; in the welding friction stage, the rotation speed of the middlepiece is adjusted to pulsate between the preset peak speed and the preset valley speed with a preset period, so that the temperature field of the entire welding interface and each area of ​​its neighborhood is controlled within a preset temperature range, and the difference between the upper and lower limits of the preset temperature range and the solid phase change temperature of the workpiece to be welded is less than a preset threshold value; after the timing reaches a first duration, the rotation speed of the middlepiece is reduced to stop, and the workpiece to be welded is driven by a hydraulic system to apply top forging pressure to the middlepiece, and maintained until a second duration. It can ensure that the temperature distribution of the friction welding interface and its neighborhood is uniform.

Description

Technical Field

[0001] The present application belongs to the technical field of friction welding, and in particular relates to a method, device, equipment and medium for regulating the temperature field of intermediate component rotation friction welding. Background Art

[0002] Friction welding refers to a solid-phase welding method that uses the heat generated by friction between the contact surfaces of the workpieces to be welded as a heat source to raise the temperature of the contact surfaces of the workpieces to be welded and their neighborhoods to a state of plastic deformation, and to cause the contact surfaces of the workpieces to be welded and their neighborhoods to undergo local plastic deformation under pressure to perform welding. Rotary friction welding is a method in which one of the two workpieces to be welded is clamped in a rotating fixture, called a rotating workpiece, and the other is clamped in a moving fixture, called a moving workpiece. During welding, the rotating workpiece starts to rotate at high speed driven by a motor, and the moving workpiece gradually approaches the rotating workpiece under the drive of the axial hydraulic pressure and applies friction pressure and upsetting pressure to achieve welding of the two workpieces. Due to its solid-phase welding characteristics, friction welding can avoid welding defects in the melting-solidification process of the welding zone, obtain a welded joint with good metallurgical bonding and mechanical properties, and has the characteristics of small heat-affected zone, high welding efficiency, and a wide range of weldable materials. It has been widely used in aerospace, automobile manufacturing, railway construction and other fields.

[0003] However, when the mass and length of the two workpieces to be welded are large, the workpieces are not easy to rotate, and their rotation speed cannot be effectively and flexibly controlled. At this time, it is an effective method to embed a separately manufactured intermediate piece between the two workpieces to be welded to achieve indirect connection of the workpieces to be welded. In addition, when the cross-sectional area of ​​the workpieces to be welded is large, there will be a problem of uneven distribution of the temperature field at the welding interface and its neighborhood during the welding process. In particular, the relative motion linear velocity of rotary friction welding is proportional to the position radius. The linear velocity of the axial center of the rotating part is lower, while the linear velocity of the outer edge is higher, resulting in uneven heat generation along the radial direction of the welding interface. This uneven heat generation will lead to uneven temperature distribution at the friction welding interface and its neighborhood, significantly affecting the microstructure distribution of the joint, and thus affecting its overall mechanical properties. Summary of the invention

[0004] The embodiments of the present application provide a method, device, equipment and medium for regulating the temperature field of intermediate component rotation friction welding, which can ensure uniform temperature distribution of the friction welding interface and its neighborhood, improve the microstructure of the welded joint, and ensure the mechanical properties, service stability and life of the welded joint.

[0005] The present application provides a method for controlling the temperature field of intermediate component rotation friction welding, comprising:

[0006] The middle piece is driven to rotate continuously by a motor. After reaching a preset speed, the first workpiece to be welded and the second workpiece to be welded are driven by a hydraulic system to move toward the middle piece and apply friction pressure, and timing is started. The first workpiece to be welded and the second workpiece to be welded are respectively arranged on both sides of the axial direction of the middle piece;

[0007] During the welding friction stage, the rotation speed of the intermediate piece is adjusted so that the rotation speed is pulsated between a preset peak speed and a preset valley speed at a preset period, so that the temperature field of the entire welding interface between the intermediate piece and the first workpiece to be welded and the second workpiece to be welded and the neighboring regions thereof are controlled within a preset temperature range, and the difference between the upper and lower limits of the preset temperature range and the solid phase change temperature of the first workpiece to be welded and the second workpiece to be welded is less than a preset threshold value;

[0008] After the timing reaches the first time length, the rotation speed of the intermediate piece is reduced to stop, and the first workpiece to be welded and the second workpiece to be welded are driven by the hydraulic system to apply upsetting pressure to the intermediate piece, and the pressure is maintained for a second time length.

[0009] In some embodiments of the present application, the upper limit value of the preset temperature range is the sum of the solid-state phase change temperatures of the first workpiece to be welded and the second workpiece to be welded and the first temperature preset threshold value, and the lower limit value of the preset temperature range is the difference between the solid-state phase change temperatures of the first workpiece to be welded and the second workpiece to be welded and the second temperature preset threshold value.

[0010] In some embodiments of the present application, before adjusting the rotation speed of the intermediate member so that the rotation speed pulsates between a preset peak rotation speed and a preset valley rotation speed with a preset period, the method further includes:

[0011] The preset period is calculated according to the following formula:

[0012]

[0013] in, is the proportional coefficient set empirically, is the welding interface radius, It is the thermal diffusion coefficient of the materials of the first workpiece to be welded and the second workpiece to be welded.

[0014] In some embodiments of the present application, in a preset period, the ratio of the duration of the preset peak speed to the duration of the preset valley speed meets the following conditions:

[0015]

[0016] in, Obtained by the following formula:

[0017]

[0018] in, One speed pulsation cycle t Preset peak speed duration, One speed pulsation cycle t Preset valley speed duration, It is a proportional coefficient set by experience. In the preset cycle, the time of the speed increase section and the speed decrease section accounts for 10%-20% of the entire cycle.

[0019] In some embodiments of the present application, during the welding friction stage, adjusting the rotation speed of the intermediate piece includes:

[0020] During the welding friction stage, the rotation speed of the intermediate piece is periodically adjusted using a trapezoidal wave or a sine wave.

[0021] In some embodiments of the present application, when a sine wave is used to periodically regulate the rotational speed of the middleware, in the sine wave, the time within the first preset speed range is used as the duration of the preset peak speed, and the time within the second preset speed range is used as the duration of the preset valley speed. The first preset speed range is a range determined based on the preset peak speed plus or minus a preset percentage, and the second preset speed range is a range determined based on the preset valley speed plus or minus a preset percentage.

[0022] In some embodiments of the present application, the first workpiece to be welded and the second workpiece to be welded are a first steel rail and a second steel rail respectively arranged on both axial sides of the intermediate piece, and the solid phase transition temperature is an austenite phase transition temperature.

[0023] In some embodiments of the present application, the first temperature preset threshold is determined based on the austenite phase transformation rate of the first workpiece to be welded and the second workpiece to be welded. The higher the austenite phase transformation rate, the smaller the first temperature preset threshold; the lower limit value of the preset temperature range is at least higher than the dynamic recrystallization temperature of the first workpiece to be welded and the second workpiece to be welded during the friction welding process.

[0024] In a second aspect, an embodiment of the present application provides a temperature field control device for middleware rotation friction welding, comprising:

[0025] A motor, used to drive the intermediate piece to rotate continuously;

[0026] A hydraulic system is used to clamp the first workpiece to be welded and the second workpiece to be welded, and after the intermediate piece reaches a preset rotation speed, the first workpiece to be welded and the second workpiece to be welded are driven to move toward the intermediate piece and apply friction pressure, and the first workpiece to be welded and the second workpiece to be welded are respectively arranged on both sides of the axial direction of the intermediate piece;

[0027] A controller that does the following:

[0028] When the first workpiece to be welded and the second workpiece to be welded begin to apply friction pressure to the intermediate piece, the timing is started; in the welding friction stage, the rotation speed of the intermediate piece is adjusted so that the rotation speed is pulsated between a preset peak speed and a preset valley speed with a preset period, so that the temperature field of the entire welding interface between the intermediate piece and the first workpiece to be welded and the second workpiece to be welded and the neighboring regions thereof are controlled within a preset temperature range, and the difference between the upper and lower limits of the preset temperature range and the solid phase change temperature of the first workpiece to be welded and the second workpiece to be welded is less than a preset threshold value;

[0029] After the timing reaches the first time length, the rotation speed of the intermediate piece is reduced to a stop by the motor, and the first workpiece to be welded and the second workpiece to be welded are driven by the hydraulic system to apply upsetting pressure to the intermediate piece and maintain the pressure for a second time length.

[0030] In some embodiments of the present application, the upper limit value of the preset temperature range is the sum of the solid-state phase change temperatures of the first workpiece to be welded and the second workpiece to be welded and the first temperature preset threshold value, and the lower limit value of the preset temperature range is the difference between the solid-state phase change temperatures of the first workpiece to be welded and the second workpiece to be welded and the second temperature preset threshold value.

[0031] In a third aspect, an embodiment of the present application provides a temperature field control device for middleware rotation friction welding, the device comprising: a processor and a memory storing computer program instructions;

[0032] When the processor executes the computer program instructions, the middleware rotation friction welding temperature field control method of any of the above embodiments is implemented.

[0033] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium having computer program instructions stored thereon. When the computer program instructions are executed by a processor, the method for controlling the temperature field of middleware rotational friction welding of any of the above embodiments is implemented.

[0034] Through the middlepiece rotation friction welding temperature field control method, device, equipment and medium provided in the embodiments of the present application, in the welding friction stage, the rotation speed of the middlepiece is driven by a motor to pulsate between a preset peak speed and a preset valley speed with a preset period, so that the temperature field of the entire welding interface and each area of ​​its neighborhood is controlled within a preset temperature range, and the difference between the upper and lower limits of the preset temperature range and the solid-state phase change temperature of the first workpiece to be welded and the second workpiece to be welded is less than a preset threshold value. Therefore, the temperature of the welding interface and its neighborhood can be controlled near the solid-state phase change temperature of the first workpiece to be welded and the second workpiece to be welded, which can ensure uniform temperature distribution of the friction welding interface and its neighborhood, improve the microstructure of the welding joint area, and ensure the mechanical properties, service stability and life of the welding joint. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solution of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0036] Figure 1 A schematic flow chart of a method for controlling the temperature field of middleware rotational friction welding provided in an embodiment of the present application;

[0037] Figure 2 A schematic diagram of a method for implementing friction welding of a rotating rail of an intermediate piece provided in an embodiment of the present application;

[0038] Figure 3 A schematic diagram of a temperature field control method for middleware rotational friction welding provided in an embodiment of the present application;

[0039] Figure 4 A schematic diagram of the heat generation and heat dissipation process in the high temperature zone and the low temperature zone of the welding interface during the rotational friction stage of the intermediate piece provided in an embodiment of the present application;

[0040] Figure 5 A schematic diagram of temperature changes and distribution in various regions of the middle piece rotational friction welding interface provided in an embodiment of the present application;

[0041] Figure 6 A schematic diagram of the structure of the temperature field control device for middleware rotation friction welding provided in an embodiment of the present application;

[0042] Figure 7 A schematic diagram of the structure of the temperature field control device for the intermediate piece rotation friction welding provided in an embodiment of the present application. DETAILED DESCRIPTION

[0043] The features and exemplary embodiments of various aspects of the present application will be described in detail below. In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present application, rather than to limit the present application. For those skilled in the art, the present application can be implemented without the need for some of these specific details. The following description of the embodiments is only to provide a better understanding of the present application by illustrating the examples of the present application.

[0044] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "include..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0045] Friction welding refers to a solid-phase welding method that uses the heat generated by friction between the contact surfaces of the workpieces to be welded as a heat source to raise the temperature of the contact surfaces of the workpieces to be welded and their neighborhoods to a state of plastic deformation, and to cause the contact surfaces of the workpieces to be welded and their neighborhoods to undergo local plastic deformation under pressure to perform welding. Rotary friction welding is a method in which one of the two workpieces to be welded is clamped in a rotating fixture, called a rotating workpiece, and the other is clamped in a moving fixture, called a moving workpiece. During welding, the rotating workpiece starts to rotate at high speed driven by a motor, and the moving workpiece gradually approaches the rotating workpiece under the drive of the axial hydraulic pressure and applies friction pressure and upsetting pressure to achieve welding of the two workpieces. Due to its solid-phase welding characteristics, friction welding can avoid welding defects in the melting-solidification process of the welding zone, obtain a welded joint with good metallurgical bonding and mechanical properties, and has the characteristics of small heat-affected zone, high welding efficiency, and a wide range of weldable materials. It has been widely used in aerospace, automobile manufacturing, railway construction and other fields.

[0046] However, when the mass and length of the two workpieces to be welded are large, the workpieces are not easy to rotate, and their rotation speed cannot be effectively and flexibly controlled. At this time, it is an effective method to embed a separately manufactured intermediate piece between the two workpieces to be welded to achieve indirect connection of the workpieces to be welded. In addition, when the cross-sectional area of ​​the workpieces to be welded is large, there will be a problem of uneven distribution of the temperature field at the welding interface and its neighborhood during the welding process. In particular, the relative motion linear velocity of rotary friction welding is proportional to the position radius. The linear velocity of the axial center of the rotating part is lower, while the linear velocity of the outer edge is higher, resulting in uneven heat generation along the radial direction of the welding interface. This uneven heat generation will lead to uneven temperature distribution at the friction welding interface and its neighborhood, significantly affecting the microstructure distribution of the joint, and thus affecting its overall mechanical properties.

[0047] Specifically, excessively high or low temperatures in various parts of the welding area may lead to uneven structures, and it is difficult to ensure the mechanical properties of the joints, especially when welding large-sized or complex-shaped workpieces. In addition, for rail materials, although friction welding can achieve solid-phase connection, if the temperature of the welding interface and its neighborhood is too high, a large amount of austenite phase transformation will occur during the friction process, and after cooling, it is easy to obtain a joint containing brittle martensite structure, resulting in a significant decrease in mechanical properties such as strength and toughness relative to the parent material. If post-weld heat treatment is performed, it will continue to cause uneven hardness distribution in the transition zone between the joint and the parent material, reducing the performance of the welded rail seamless line welded joint.

[0048] The embodiments of the present application provide a method, device, equipment and medium for regulating the temperature field of intermediate component rotation friction welding, which can ensure uniform temperature distribution of the friction welding interface and its neighborhood, improve the microstructure of the welded joint, and ensure the mechanical properties, service stability and life of the welded joint.

[0049] Figure 1 A schematic flow chart of a method for controlling the temperature field of middleware rotational friction welding provided in an embodiment of the present application;

[0050] Figure 2 A schematic diagram of a method for implementing friction welding of a rotating rail of an intermediate piece provided in an embodiment of the present application;

[0051] First, the temperature field control method of the intermediate component rotation friction welding provided by the embodiment of the present application is introduced. Figure 1 As shown, the temperature field control method of the intermediate component rotation friction welding includes the following steps:

[0052] S110, driving the middle piece to rotate continuously by a motor, and after reaching a preset speed, driving the first workpiece to be welded and the second workpiece to be welded respectively by a hydraulic system to move toward the middle piece and apply friction pressure, and starting timing, the first workpiece to be welded and the second workpiece to be welded are respectively arranged on both sides of the axial direction of the middle piece;

[0053] In some embodiments of the present application, the middle piece is a specially manufactured middle connecting piece, and the first workpiece to be welded and the second workpiece to be welded are a first steel rail and a second steel rail respectively arranged on both axial sides of the middle piece.

[0054] refer to Figure 2, the first rail 220 and the second rail 230 are respectively arranged on both sides of the middle piece 210, and the middle piece rotating rail friction welding device disclosed in the invention patent ZL202210108261.X can be used to achieve the welding of the middle piece 210, the first rail 220 and the second rail 230. In the specific operation, the middle piece is driven by the motor to rotate continuously, and after reaching the set speed, the hydraulic system drives the first rail 220 and the second rail 230 to move toward the middle piece 210 and apply friction pressure.

[0055] Of course, the temperature field control method for intermediate piece rotational friction welding provided in the embodiment of the present application is also applicable to other workpieces, specifically, it can also be used for rotational friction welding of other large-section or non-rotating irregular-section workpieces.

[0056] S120, in the welding friction stage, adjusting the rotation speed of the intermediate piece so that the rotation speed pulsates between a preset peak speed and a preset valley speed at a preset period, so that the temperature field of the entire welding interface between the intermediate piece and the first workpiece to be welded and the second workpiece to be welded and the neighboring regions thereof are controlled within a preset temperature range, and the difference between the upper and lower limits of the preset temperature range and the solid phase change temperature of the first workpiece to be welded and the second workpiece to be welded is less than a preset threshold value;

[0057] In some embodiments of the present application, the solid-state phase transition temperature is an austenite phase transition temperature.

[0058] Specifically, during the welding friction stage, by adjusting the rotation speed of the intermediate piece ω , so that it is at the preset peak speed ω peak and preset valley speed ω min The heat generation rate of the rotating friction welding interface q = ητ ωr ,in η is the thermomechanical efficiency of friction, τ is the friction shear stress, r The radius of the position, the heat generated is unevenly distributed in the radial direction of the interface. Therefore, this rotation speed change provides a periodically changing heat input, and uses the difference between the heat generation rate and the heat diffusion rate to avoid the local accumulation of heat at the position with a higher heat generation rate, providing time for heat conduction in the radial direction of the welding interface and the axial direction of the joint area, increasing the welding interface temperature near the rotating axis, and promoting the temperature distribution of each area of ​​the welding interface to be uniform.

[0059] In some embodiments of the present application, the upper limit value of the preset temperature range is the sum of the solid-state phase change temperatures of the first workpiece to be welded and the second workpiece to be welded and the first temperature preset threshold value, and the lower limit value of the preset temperature range is the difference between the solid-state phase change temperatures of the first workpiece to be welded and the second workpiece to be welded and the second temperature preset threshold value.

[0060] In some embodiments of the present application, the first temperature preset threshold is determined based on the austenite phase transformation rate of the first workpiece to be welded and the second workpiece to be welded. The higher the austenite phase transformation rate, the smaller the first temperature preset threshold; the lower limit value of the preset temperature range is at least higher than the dynamic recrystallization temperature of the first workpiece to be welded and the second workpiece to be welded during the friction welding process.

[0061] Specifically, for rail friction welding, according to the austenite phase transformation temperature A1 of the welded steel, the temperature T of each area of ​​the rail and the intermediate welding interface during the friction stage is controlled so that the maximum temperature T max It does not exceed the austenite phase transition temperature A1 or is within a small range near Δ1 (A1+Δ1), where A1+Δ1 is the upper limit of the preset temperature range, A1 is the solid phase transition temperature of the first workpiece to be welded and the second workpiece to be welded, and Δ1 is the first temperature preset threshold. It can inhibit the austenitization of the rail material during the friction stage, thereby avoiding the formation of brittle martensite structure after welding cooling, making the microstructure of the joint area closer to the parent material structure. The lowest temperature of the welding interface T min It should be higher than the set lower temperature limit A1-Δ2, where A1-Δ2 is the lower limit of the preset temperature range, A1 is the solid phase change temperature of the first workpiece to be welded and the second workpiece to be welded, and Δ2 is the second temperature preset threshold value, which can ensure sufficient heat input to the joint and achieve good metallurgical bonding of the interface through the recrystallization process.

[0062] Furthermore, the temperature range Δ1 is determined by the austenite transformation rate of the rail material. Specifically, the higher the transformation rate, the smaller the value of Δ1 should be to avoid the joint having time to undergo austenite transformation. The lower limit temperature range Δ2 is determined by the recrystallization temperature of the rail material. A1-Δ2 should be at least higher than the dynamic recrystallization temperature of the material during friction welding to achieve full welding (metallurgical bonding) of the joint.

[0063] In this way, by controlling the rotation speed of the intermediate piece to pulsate between a preset peak speed and a preset valley speed with a preset period, the temperature field of the entire welding interface between the intermediate piece and the first workpiece to be welded and the second workpiece to be welded and its neighboring areas can be controlled near the solid-state phase change temperature of the first workpiece to be welded and the second workpiece to be welded, thereby suppressing the solid-state phase change process in the joint area, and then avoiding the formation of unexpected structures after cooling, improving the microstructure of the welding joint area, eliminating post-weld heat treatment, and obtaining a welding joint with strength and toughness equivalent to the parent material and uniform hardness distribution.

[0064] S130, after the timing reaches the first time length, the rotation speed of the intermediate piece is reduced to stop, and the first workpiece to be welded and the second workpiece to be welded are driven by the hydraulic system to apply upsetting pressure to the intermediate piece, and the pressure is maintained for a second time length.

[0065] Among them, the first duration and the second duration can both be obtained through experiments.

[0066] When the specified friction time is reached and the temperature field of the entire welding interface is controlled near A1, the speed of the middle piece is rapidly reduced to a stop, and the hydraulic system drives the rails on both sides to rapidly apply upsetting pressure to the middle piece. After maintaining the pressure for a period of time, the welding process is completed.

[0067] Through the middlepiece rotation friction welding temperature field control method provided in the embodiment of the present application, in the welding friction stage, the rotation speed of the middlepiece is driven by a motor to pulsate between a preset peak speed and a preset valley speed with a preset period, so that the temperature field of the entire welding interface and each area of ​​its neighborhood is controlled within a preset temperature range, and the difference between the upper and lower limits of the preset temperature range and the solid-state phase change temperature of the first workpiece to be welded and the second workpiece to be welded is less than a preset threshold value. Therefore, the temperature of the welding interface and its neighborhood can be controlled near the solid-state phase change temperature of the first workpiece to be welded and the second workpiece to be welded, which can ensure uniform temperature distribution of the friction welding interface and its neighborhood, improve the microstructure of the welding joint area, and ensure the mechanical properties, service stability and life of the welding joint.

[0068] Figure 3 A schematic diagram of a temperature field control method for middleware rotational friction welding provided in an embodiment of the present application;

[0069] Figure 4 A schematic diagram of the heat generation and heat dissipation process in the high temperature zone and the low temperature zone of the welding interface during the rotational friction stage of the intermediate piece provided in an embodiment of the present application;

[0070] Figure 5 A schematic diagram of temperature changes and distribution in various regions of the middle piece rotational friction welding interface provided in an embodiment of the present application;

[0071] In some embodiments of the present application, before adjusting the rotation speed of the intermediate component so that the rotation speed pulsates between a preset peak rotation speed and a preset valley rotation speed with a preset period, the method further includes:

[0072] The preset period is calculated according to the following formula:

[0073]

[0074] in, is the proportional coefficient set empirically, is the welding interface radius, It is the thermal diffusion coefficient of the materials of the first workpiece to be welded and the second workpiece to be welded.

[0075] In some embodiments of the present application, in a preset period, the ratio of the duration of the preset peak speed to the duration of the preset valley speed meets the following conditions:

[0076]

[0077] in, Obtained by the following formula:

[0078]

[0079] in, One speed pulsation cycle t Preset peak speed duration, One speed pulsation cycle t Preset valley speed duration, It is a proportional coefficient set by experience. In the preset cycle, the time of the speed increase section and the speed decrease section accounts for 10%-20% of the entire cycle.

[0080] In some embodiments of the present application, during the welding friction stage, adjusting the rotation speed of the intermediate piece includes:

[0081] During the welding friction stage, the rotation speed of the intermediate piece is periodically adjusted using a trapezoidal wave or a sine wave.

[0082] Specifically, in order to achieve smoother speed control, a trapezoidal wave or a sine wave can be used as the middleware speed ω Under the premise of ensuring sufficient heat generation from interface friction, the relatively gentle rise and fall process helps to reduce the impact load of rotating mechanical parts.

[0083] Use trapezoidal wave as the middleware speed ω Taking the periodic control method as an example, the middleware speed ωAccording to Figure 3 The trapezoidal wave shown in the figure changes periodically. t Related to the time scale of heat diffusion, if the heat can be fully diffused on the welding interface in a shorter time, a smaller cycle can be used. t ,cycle t It can be measured experimentally.

[0084] Furthermore, the cycle t It can be expressed by the formula: t = ηR 2 / a To estimate, η is the proportional coefficient set empirically, R is the radius of the rail cross-section envelope, a It is the thermal diffusion coefficient of the rail material. As the welding process progresses, the temperature of the welding interface gradually increases, and the thermal diffusion coefficient changes, so the speed pulsation cycle can be dynamically adjusted.

[0085] The heat generation and heat dissipation process of the welding interface is as follows Figure 4 As shown in the figure, by adjusting the speed parameters, the high temperature zone and the low temperature zone have approximately the same heat accumulation during welding. ω peak During the duration, friction heat accumulates rapidly and in large quantities at the outer edge of the welding interface (or at 2 / 3 radius), so the preset peak speed needs to be strictly controlled. Duration t peak Avoid the highest temperature in the high temperature zone T max Exceed A1+Δ1 or exceed A1 for a long time. ω min During the duration, the interface generates less heat, which provides time for the heat from the high temperature area of ​​the interface to transfer to the low temperature area. At this time, it is necessary to control the preset valley speed. Duration t min The duration of time to ensure the minimum interface temperature T min Reach A1-Δ2, with sufficient heat for recrystallization and metallurgical bonding. For materials with a larger weld interface radius or a smaller thermal diffusion coefficient, it is necessary to increase the total heat input without affecting the total heat input. t min The time length allows the heat to be fully transferred to the low temperature area of ​​the axis, thereby improving the temperature uniformity of the welding interface. Finally, the temperature change process of each area of ​​the welding interface is obtained as follows: Figure 4 shown.

[0086] Furthermore, the peak and valley time ratiosk = t peak / t min , can be expressed by the formula: k = ξ / ( ω peak t ) is estimated, where ξ It is the proportional coefficient. The speed increase and decrease time can be set to 10%-20% of the whole cycle. The specific value can be adjusted according to experimental experience and equipment performance.

[0087] In some embodiments of the present application, when a sine wave is used to periodically regulate the rotational speed of the middleware, in the sine wave, the time within the first preset speed range is used as the duration of the preset peak speed, and the time within the second preset speed range is used as the duration of the preset valley speed. The first preset speed range is a range determined based on the preset peak speed plus or minus a preset percentage, and the second preset speed range is a range determined based on the preset valley speed plus or minus a preset percentage.

[0088] Among them, the preset percentage can be 10%, that is, the time within the range of ±10% of the preset peak speed is used as the duration of the preset peak speed, and the time within the range of ±10% of the preset valley speed is used as the duration of the preset valley speed, which is convenient for statistics of the duration. The preset percentage can also be other values, which can be set according to actual conditions.

[0089] In combination with the above embodiments, the method for controlling the temperature field of the intermediate component rotation friction welding provided in the embodiments of the present application has the following advantages:

[0090] 1. It can accurately control the heat input of each area of ​​the welding interface during the friction stage, inhibit the solid phase change process in the joint area, thereby avoiding the formation of unexpected microstructures after cooling, improving the microstructure of the welding joint area, eliminating the need for post-weld heat treatment, and obtaining a welding joint with strength and toughness equivalent to that of the parent material and uniform hardness distribution.

[0091] 2. For rotary friction welding of large or special-shaped cross-sections, a relatively uniform temperature distribution can be achieved at different welding interface radii, eliminating welding defects caused by uneven radial distribution of friction heat, thereby greatly improving the microstructural consistency and overall mechanical properties of the welded joint.

[0092] 3. It can reduce the load torque and impact load required by welding equipment when driving the middleware to rotate, improve the reliability and stability of equipment operation; reduce equipment energy consumption and extend equipment service life.

[0093] Figure 6A schematic diagram of the structure of the temperature field control device for middleware rotation friction welding provided in an embodiment of the present application;

[0094] Next, the temperature field control device for the intermediate component rotation friction welding provided by the embodiment of the present application is introduced. Figure 6 As shown, the friction welding device comprises:

[0095] Motor 601, used to drive the intermediate piece to rotate continuously;

[0096] A hydraulic system 602 is used to clamp the first workpiece to be welded and the second workpiece to be welded, and after the intermediate piece reaches a preset rotation speed, the first workpiece to be welded and the second workpiece to be welded are driven to move toward the intermediate piece and apply friction pressure, and the first workpiece to be welded and the second workpiece to be welded are respectively arranged on both sides of the axial direction of the intermediate piece;

[0097] The controller 603 is used to perform the following operations:

[0098] When the first workpiece to be welded and the second workpiece to be welded begin to apply friction pressure to the intermediate piece, the timing is started; in the welding friction stage, the rotation speed of the intermediate piece is adjusted so that the rotation speed is pulsated between a preset peak speed and a preset valley speed with a preset period, so that the temperature field of the entire welding interface between the intermediate piece and the first workpiece to be welded and the second workpiece to be welded and the neighboring regions thereof are controlled within a preset temperature range, and the difference between the upper and lower limits of the preset temperature range and the solid phase change temperature of the first workpiece to be welded and the second workpiece to be welded is less than a preset threshold value;

[0099] After the timing reaches the first time length, the rotation speed of the intermediate piece is reduced to a stop by the motor 601, and the first workpiece to be welded and the second workpiece to be welded are driven by the hydraulic system 602 to apply upsetting pressure to the intermediate piece and maintain the pressure for a second time length.

[0100] In some embodiments of the present application, the upper limit value of the preset temperature range is the sum of the solid-state phase change temperatures of the first workpiece to be welded and the second workpiece to be welded and the first temperature preset threshold value, and the lower limit value of the preset temperature range is the difference between the solid-state phase change temperatures of the first workpiece to be welded and the second workpiece to be welded and the second temperature preset threshold value.

[0101] In some embodiments of the present application, the controller 603 is specifically used to: before adjusting the rotation speed of the middleware so that the rotation speed pulsates between a preset peak speed and a preset valley speed with a preset period, calculate the preset period according to the following formula:

[0102]

[0103] in, is the proportional coefficient set empirically, is the welding interface radius, It is the thermal diffusion coefficient of the materials of the first workpiece to be welded and the second workpiece to be welded.

[0104] In some embodiments of the present application, in a preset period, the ratio of the duration of the preset peak speed to the duration of the preset valley speed meets the following conditions:

[0105]

[0106] in, Obtained by the following formula:

[0107]

[0108] in, One speed pulsation cycle t Preset peak speed duration, One speed pulsation cycle t Preset valley speed duration, It is a proportional coefficient set by experience. In the preset cycle, the time of the speed increase section and the speed decrease section accounts for 10%-20% of the entire cycle.

[0109] In some embodiments of the present application, the controller 603 is specifically used to:

[0110] During the welding friction stage, the rotation speed of the intermediate piece is periodically adjusted using a trapezoidal wave or a sine wave.

[0111] In some embodiments of the present application, the controller 603 is also used to: when using a sine wave to periodically regulate the speed of the middleware, in the sine wave, the time within the first preset speed range is used as the duration of the preset peak speed, and the time within the second preset speed range is used as the duration of the preset valley speed, the first preset speed range is a range determined based on the preset peak speed plus or minus a preset percentage, and the second preset speed range is a range determined based on the preset valley speed plus or minus a preset percentage.

[0112] In some embodiments of the present application, the first workpiece to be welded and the second workpiece to be welded are respectively a first steel rail and a second steel rail arranged on both axial sides of the intermediate piece, and the solid phase transition temperature is an austenite phase transition temperature.

[0113] In some embodiments of the present application, the first temperature preset threshold is determined based on the austenite phase transformation rate of the first workpiece to be welded and the second workpiece to be welded. The higher the austenite phase transformation rate, the smaller the first temperature preset threshold; the lower limit value of the preset temperature range is at least higher than the dynamic recrystallization temperature of the first workpiece to be welded and the second workpiece to be welded during the friction welding process.

[0114] By means of the temperature field control device for rotating friction welding of the intermediate piece provided in the embodiment of the present application, in the welding friction stage, the rotation speed of the intermediate piece is driven by a motor to pulsate between a preset peak speed and a preset valley speed at a preset period, so that the temperature field of the entire welding interface and each area of ​​its neighborhood is controlled within a preset temperature range, and the difference between the upper and lower limits of the preset temperature range and the solid-state phase change temperature of the first workpiece to be welded and the second workpiece to be welded is less than a preset threshold value. Therefore, the temperature of the welding interface and its neighborhood can be controlled near the solid-state phase change temperature of the first workpiece to be welded and the second workpiece to be welded, which can ensure uniform temperature distribution of the friction welding interface and its neighborhood, improve the microstructure of the welding joint area, and ensure the mechanical properties, service stability and life of the welding joint.

[0115] Figure 7 A schematic diagram of the structure of a temperature field control device for middleware rotation friction welding provided in an embodiment of the present application;

[0116] The middleware rotation friction welding temperature field regulating device may include a processor 701 and a memory 702 storing computer program instructions.

[0117] Specifically, the processor 701 may include a central processing unit (CPU), or an application specific integrated circuit (ASIC), or may be configured to implement one or more integrated circuits of the embodiments of the present application.

[0118] The memory 702 may include a large capacity memory for data or instructions. By way of example and not limitation, the memory 702 may include a hard disk drive (HDD), a floppy disk drive, a flash memory, an optical disk, a magneto-optical disk, a magnetic tape, or a universal serial bus (USB) drive or a combination of two or more of these. In appropriate cases, the memory 702 may include a removable or non-removable (or fixed) medium. In appropriate cases, the memory 702 may be inside or outside the integrated gateway disaster recovery device. In a specific embodiment, the memory 702 is a non-volatile solid-state memory.

[0119] The memory may include a read-only memory (ROM), a random access memory (RAM), a magnetic disk storage medium device, an optical storage medium device, a flash memory device, an electrical, optical or other physical / tangible memory storage device. Thus, typically, the memory includes one or more tangible (non-transitory) computer-readable storage media (e.g., a memory device) encoded with software including computer-executable instructions, and when the software is executed (e.g., by one or more processors), it is operable to perform the operations described with reference to the method according to the first aspect of the present disclosure.

[0120] The processor 701 reads and executes the computer program instructions stored in the memory 702 to implement the temperature field control method for the middleware rotation friction welding in the above embodiment.

[0121] In one example, the middleware rotation friction welding temperature field control device may also include a communication interface 703 and a bus 710. Figure 7 As shown, the processor 701, the memory 702, and the communication interface 703 are connected via a bus 710 and communicate with each other.

[0122] The communication interface 703 is mainly used to implement communication between various modules, devices, units and / or equipment in the embodiments of the present application.

[0123] The bus 710 includes hardware, software or both, coupling the components of the friction welding device to each other. For example and not limitation, the bus may include an accelerated graphics port (AGP) or other graphics bus, an enhanced industrial standard architecture (EISA) bus, a front-side bus (FSB), a hypertransport (HT) interconnect, an industrial standard architecture (ISA) bus, an infinite bandwidth interconnect, a low pin count (LPC) bus, a memory bus, a microchannel architecture (MCA) bus, a peripheral component interconnect (PCI) bus, a PCI-Express (PCI-X) bus, a serial advanced technology attachment (SATA) bus, a video electronics standard association local (VLB) bus or other suitable bus or a combination of two or more of these. Where appropriate, the bus 710 may include one or more buses. Although the present application embodiment describes and illustrates a specific bus, the present application considers any suitable bus or interconnect.

[0124] The middleware rotation friction welding temperature field control device executes the middleware rotation friction welding temperature field control method in the embodiment of the present application, thereby achieving Figure 1 The temperature field control method of the intermediate part rotation friction welding is shown.

[0125] In addition, in combination with the middleware rotation friction welding temperature field control method in the above embodiment, the present application embodiment can provide a computer storage medium for implementation. The computer storage medium stores computer program instructions; when the computer program instructions are executed by the processor, any one of the middleware rotation friction welding temperature field control methods in the above embodiment is implemented.

[0126] In combination with the middleware rotation friction welding temperature field control method in the above embodiment, the embodiment of the present application also provides a computer program product. When the instructions in the computer program product are executed by the processor of an electronic device, the electronic device executes the middleware rotation friction welding temperature field control method in any of the above embodiments.

[0127] It should be clear that the present application is not limited to the specific configuration and processing described above and shown in the figures. For the sake of simplicity, a detailed description of the known method is omitted here. In the above embodiments, several specific steps are described and shown as examples. However, the method process of the present application is not limited to the specific steps described and shown, and those skilled in the art can make various changes, modifications and additions, or change the order between the steps after understanding the spirit of the present application.

[0128] The functional blocks shown in the structural block diagram described above can be implemented as hardware, software, firmware or a combination thereof. When implemented in hardware, it can be, for example, an electronic circuit, an application-specific integrated circuit (ASIC), appropriate firmware, a plug-in, a function card, etc. When implemented in software, the elements of the present application are programs or code segments used to perform the required tasks. The program or code segment can be stored in a machine-readable medium, or transmitted on a transmission medium or a communication link by a data signal carried in a carrier. "Machine-readable medium" may include any medium capable of storing or transmitting information. Examples of machine-readable media include electronic circuits, semiconductor memory devices, ROMs, flash memories, erasable ROMs (EROMs), floppy disks, CD-ROMs, optical disks, hard disks, optical fiber media, radio frequency (RF) links, etc. The code segment can be downloaded via a computer network such as the Internet, an intranet, etc.

[0129] It should also be noted that the exemplary embodiments mentioned in this application describe some methods or systems based on a series of steps or devices. However, this application is not limited to the order of the above steps, that is, the steps can be performed in the order mentioned in the embodiment, or in a different order from the embodiment, or several steps can be performed simultaneously.

[0130] The above reference is made to the flowcharts and / or block diagrams of the methods, devices (systems) and computer program products according to the embodiments disclosed in the present application, and the various aspects disclosed in the present application are described. It should be understood that each box in the flowchart and / or block diagram and the combination of each box in the flowchart and / or block diagram can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device to produce a machine so that these instructions executed by the processor of the computer or other programmable data processing device enable the implementation of the functions / actions specified in one or more boxes of the flowchart and / or block diagram. Such a processor can be, but is not limited to, a general-purpose processor, a special-purpose processor, a special application processor, or a field programmable logic circuit. It can also be understood that each box in the block diagram and / or flowchart and the combination of boxes in the block diagram and / or flowchart can also be implemented by dedicated hardware that performs the specified function or action, or can be implemented by a combination of dedicated hardware and computer instructions.

[0131] The above is only a specific implementation of the present application. Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working processes of the systems, modules and units described above can refer to the corresponding processes in the aforementioned method embodiments, and will not be repeated here. It should be understood that the protection scope of the present application is not limited to this. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed in this application, and these modifications or replacements should be included in the protection scope of this application.

Claims

1. A method for controlling the temperature field of intermediate component rotation friction welding, characterized in that: include: The middle piece is driven to rotate continuously by a motor, and after reaching a preset speed, a first workpiece to be welded and a second workpiece to be welded are driven respectively by a hydraulic system to move toward the middle piece and apply friction pressure, and start timing, wherein the first workpiece to be welded and the second workpiece to be welded are respectively arranged on both sides of the axial direction of the middle piece; During the welding friction stage, the rotation speed of the intermediate piece is adjusted so that the rotation speed is pulsated between a preset peak rotation speed and a preset valley rotation speed at a preset period, so that the temperature field of the entire welding interface between the intermediate piece and the first workpiece to be welded and the second workpiece to be welded and the neighboring regions thereof are controlled within a preset temperature range, and the difference between the upper and lower limits of the preset temperature range and the solid phase change temperature of the first workpiece to be welded and the second workpiece to be welded is less than a preset threshold value; After the timing reaches a first time length, the rotation speed of the intermediate piece is reduced to stop, and the first workpiece to be welded and the second workpiece to be welded are driven by the hydraulic system to apply upsetting pressure to the intermediate piece, and the pressure is maintained for a second time length; Before adjusting the rotation speed of the intermediate member so that the rotation speed changes pulsatingly between a preset peak rotation speed and a preset valley rotation speed at a preset period, the method further includes: The preset period is calculated according to the following formula: in, is the proportional coefficient set empirically, is the welding interface radius, is the thermal diffusion coefficient of the materials of the first workpiece to be welded and the second workpiece to be welded.

2. The method according to claim 1, characterized in that The upper limit value of the preset temperature range is the sum of the solid phase change temperatures of the first workpiece to be welded and the second workpiece to be welded and a first temperature preset threshold value, and the lower limit value of the preset temperature range is the difference between the solid phase change temperatures of the first workpiece to be welded and the second workpiece to be welded and the second temperature preset threshold value.

3. The method according to claim 2, characterized in that In the preset period, the ratio of the duration of the preset peak speed to the duration of the preset valley speed meets the following conditions: in, Obtained by the following formula: in, One speed pulsation cycle t Preset peak speed duration, One speed pulsation cycle t Preset valley speed duration, It is a proportional coefficient set by experience. In the preset cycle, the time of the speed increase section and the speed decrease section accounts for 10%-20% of the entire cycle.

4. The method according to claim 3, characterized in that During the welding friction stage, adjusting the rotation speed of the intermediate piece comprises: During the welding friction stage, the rotation speed of the intermediate piece is periodically adjusted using a trapezoidal wave or a sine wave.

5. The method according to claim 4, characterized in that When the sine wave is used to periodically regulate the rotational speed of the middleware, in the sine wave, the time within the first preset speed range is used as the duration of the preset peak speed, and the time within the second preset speed range is used as the duration of the preset valley speed. The first preset speed range is a range determined based on the preset peak speed plus or minus a preset percentage, and the second preset speed range is a range determined based on the preset valley speed plus or minus a preset percentage.

6. The method according to any one of claims 2 to 5, characterized in that The first workpiece to be welded and the second workpiece to be welded are a first steel rail and a second steel rail respectively arranged on both sides of the intermediate piece in an axial direction, and the solid-state phase transformation temperature is an austenite phase transformation temperature.

7. The method according to claim 6, characterized in that The first temperature preset threshold is determined based on the austenite phase transformation rate of the first workpiece to be welded and the second workpiece to be welded. The higher the austenite phase transformation rate, the smaller the first temperature preset threshold; the lower limit of the preset temperature range is at least higher than the dynamic recrystallization temperature of the first workpiece to be welded and the second workpiece to be welded during the friction welding process.

8. A temperature field control device for intermediate component rotation friction welding, characterized in that: include: A motor, used to drive the intermediate piece to rotate continuously; A hydraulic system, for clamping a first workpiece to be welded and a second workpiece to be welded, and after the intermediate piece reaches a preset rotation speed, driving the first workpiece to be welded and the second workpiece to be welded to move toward the intermediate piece and apply friction pressure, wherein the first workpiece to be welded and the second workpiece to be welded are respectively arranged on both sides of the axial direction of the intermediate piece; A controller that does the following: When the first workpiece to be welded and the second workpiece to be welded begin to apply friction pressure to the intermediate piece, timing is started; in the welding friction stage, the rotation speed of the intermediate piece is adjusted so that the rotation speed is pulsated between a preset peak speed and a preset valley speed with a preset period, so that the temperature field of the entire welding interface between the intermediate piece and the first workpiece to be welded and the second workpiece to be welded and the neighboring regions thereof is controlled within a preset temperature range, and the difference between the upper and lower limits of the preset temperature range and the solid phase change temperature of the first workpiece to be welded and the second workpiece to be welded is less than a preset threshold value; After the timing reaches a first time length, the motor is used to reduce the rotation speed of the intermediate piece to a stop, and the hydraulic system is used to drive the first workpiece to be welded and the second workpiece to be welded to apply an upsetting pressure to the intermediate piece, and the pressure is maintained for a second time length; The preset period is calculated according to the following formula: in, is the proportional coefficient set empirically, is the welding interface radius, is the thermal diffusion coefficient of the materials of the first workpiece to be welded and the second workpiece to be welded.

9. The device according to claim 8, characterized in that The upper limit value of the preset temperature range is the sum of the solid phase change temperatures of the first workpiece to be welded and the second workpiece to be welded and a first temperature preset threshold value, and the lower limit value of the preset temperature range is the difference between the solid phase change temperatures of the first workpiece to be welded and the second workpiece to be welded and the second temperature preset threshold value.

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