Welding method for feeding back and adjusting morphology of molybdenum-rhenium alloy molten pool and related device
By using a feedback regulation method to monitor and control the temperature and morphology of the molybdenum-rhenium alloy molten pool in real time, the problem of unstable molten pool morphology during the welding process of molybdenum-rhenium alloy was solved, high-quality welding was achieved, and the mechanical properties and reliability of the welded joint were improved. This method is applicable to fields such as aerospace and nuclear reactors.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- XI'AN UNIVERSITY OF ARCHITECTURE AND TECHNOLOGY
- Filing Date
- 2026-03-26
- Publication Date
- 2026-05-15
AI Technical Summary
The morphology of the molten pool is difficult to control stably during the welding of molybdenum-rhenium alloys, resulting in poor welding quality and defects such as incomplete weld formation, incomplete penetration, undercut, and microcracks, which affect the mechanical properties and service reliability of the welded joint.
By adopting a feedback regulation method, a welding temperature and time distribution model is established. Combined with a dual-pulse heat source control strategy with asymmetric waveform and an infrared-thermocouple collaborative temperature measurement system, the temperature and morphology of the molten pool are monitored in real time. Temperature and stress closed-loop feedback regulation is carried out to achieve multi-dimensional control of the molten pool morphology.
It improves the welding quality of molybdenum-rhenium alloys, enhances the bonding strength of welded joints, reduces crack initiation, and improves weld fusion consistency and mechanical properties, making it suitable for manufacturing high-temperature and high-strength components for aerospace and nuclear reactors.
Smart Images
Figure CN122033504A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of electronic precision instrument technology, and relates to a welding method and related apparatus for feedback-adjusted molybdenum-rhenium alloy molten pool morphology. Background Technology
[0002] Molybdenum-rhenium alloys are increasingly used in extreme working conditions such as aero-engine combustion chambers and nuclear reactor targets due to their core properties such as high melting point, excellent high-temperature strength and good plasticity. However, during the welding process, due to the inherent characteristics of high thermal conductivity, difference in linear expansion coefficient and special fluidity of liquid metal, it is difficult to control the morphology of the molten pool. This leads to defects such as poor weld zone bonding, incomplete weld formation, incomplete penetration, undercut, and microcrack propagation, which seriously restrict the mechanical properties and service reliability of the welded joint.
[0003] Therefore, developing a real-time feedback-based molten pool morphology adjustment technology, which captures characteristic parameters such as molten pool size and surface tension through visual sensing and temperature field monitoring, and constructs a dynamic response mechanism between welding parameters and molten pool morphology to achieve closed-loop control of key parameters such as heat input and welding speed, has become a core technological requirement for overcoming the welding quality bottleneck of molybdenum-rhenium alloys and promoting their engineering applications. As a key parameter determining weld formation quality and internal structure, the dynamic changes in molten pool morphology directly affect the matching of welding heat input, arc characteristics, and the stress state of the molten pool.
[0004] In actual welding processes, due to significant differences in the structure, material properties, and thermal conductivity of the weldments, traditional welding processes face the following core challenges: Relying on experience-based preset parameters: lacking real-time data references, subject to numerous external interference factors, and resulting in slow real-time feedback.
[0005] Inconsistent heating rate in the welding area: Different thermal conductivity of the welding materials result in different heating rates, leading to differences in heat transfer paths and heat dissipation areas. Under the same conditions, uneven temperature is likely to occur, and some welding points may overheat or fail to melt.
[0006] The welding heat source cannot be precisely controlled: Traditional heat sources cannot adjust the heat input to welding zones at different temperatures, which can easily lead to heat accumulation and cause local thermal stress.
[0007] The welding control mechanism is too simplistic: traditional welding control systems are unable to adapt to the fluctuations in the molten pool caused by thermal disturbances in molybdenum-rhenium alloys, and lack relevant scientific parameters.
[0008] Poor bonding between the base metal and the weld zone: Uneven heat input in the molten pool leads to coarse grains in the heat-affected zone of the base metal, resulting in overheating and gaps at the interface between the weld and the base metal.
[0009] Stress concentration causes defects: During the welding heating process, the large temperature gradient leads to thermal expansion, which causes elastic compressive stress. During the cooling process, the metal volume shrinkage is hindered, generating tensile stress. Stress is likely to occur in the heat-affected zone and fusion line, causing crack initiation and stress concentration, resulting in a reduction in the performance of the weldment.
[0010] Current research on the coordinated control of temperature and stress distribution in the welding process using multiple parameters is relatively limited, and there is a lack of statistical thinking for overall dynamic adjustment, which makes it difficult to meet the process requirements of high-temperature resistant structural components and precision components of nuclear reactors in terms of welding quality. Summary of the Invention
[0011] The purpose of this invention is to provide a welding method and related apparatus for feedback regulation of the molten pool morphology of molybdenum-rhenium alloy, thereby solving the problem of the lack of overall dynamic regulation in existing welding processes.
[0012] To achieve the above objectives, the present invention employs the following technical solution: A welding method for feedback-controlled molten pool morphology of molybdenum-rhenium alloy includes: A welding temperature and time distribution model was established for the welding area of molybdenum-rhenium alloy. The temperature change law of the welding area was deduced based on the characteristic parameters of the molybdenum-rhenium alloy welded parts. The morphology of the weld pool was monitored in real time and the heating process was controlled by a feedback mechanism. A dual-pulse heat source control strategy with asymmetric waveform is adopted for heat source input. Based on the real-time monitoring of the internal morphology and temperature data of the molten pool during the welding process, the overall temperature field distribution on the surface of the molten pool is obtained. Temperature adjustment is performed at the points of uneven temperature distribution to control the temperature of the molten pool. Based on the real-time prediction of residual thermal stress caused by welding by the molybdenum-rhenium alloy material itself, the stress level in the welding area is controlled by closed-loop feedback through temperature regulation. Based on the welding temperature and time distribution model, and combined with the control of the molten pool temperature and the stress level in the welding zone, a closed-loop feedback adjustment of the molten pool morphology of the molybdenum-rhenium alloy during the welding process is achieved.
[0013] Furthermore, the method for constructing the welding temperature and time distribution model is as follows: Based on the three-dimensional transient heat conduction theory of temperature field and time composition in the welding zone of molybdenum-rhenium alloy molten pool, the transient heat conduction equation is solved according to the boundary and initial conditions by using the equivalent specific heat of latent heat of phase change and a Gaussian surface heat source as heat input, thereby obtaining the temperature and time distribution model of molybdenum-rhenium alloy molten pool welding.
[0014] Furthermore, the method of controlling the heating process using a feedback mechanism is as follows: During the welding process, a dual-pulse heat source power control strategy with asymmetric waveform is used to heat the weld pool area. The pulse is combined with the upper-level PID feedback control algorithm to calculate the temperature distribution. In different weld pool temperature zones, different amplitudes, frequencies and waveforms are used to adjust the heating time and cooling rate output, so that the temperature of the weld pool area is always controlled within the set value range.
[0015] Furthermore, the characteristic parameters of molybdenum-rhenium alloy welded parts include shape and structure, thermal conductivity, and coefficient of thermal expansion.
[0016] Furthermore, the method for monitoring the overall temperature field distribution on the surface of the molten pool during welding is as follows: A non-contact infrared thermometer is installed inside the molten pool to receive the infrared energy radiated from the molten pool and monitor the morphology and temperature data of the molten pool in real time. At the same time, a thermocouple sensor is installed to measure the temperature of the molten pool in contact and collect the temperature change data of the molten pool synchronously. Based on the temperature change data of the molten pool, the overall temperature field distribution on the surface of the molten pool is calculated using Planck's law.
[0017] Furthermore, the method for converting Planck's law into the overall temperature field distribution on the surface of the molten pool is as follows: Based on the shape and size of the molybdenum-rhenium alloy welded parts, the heat source in the molten pool is simplified to a point heat source. The heat conduction in the X, Y and Z directions is recorded to establish a heat source model inside the molten pool and characterize the temperature distribution during the welding process. The heat source model inside the molten pool adopts the Gaussian surface heat source model.
[0018] Furthermore, the method for real-time monitoring of the internal morphology of the molten pool during welding is as follows: During the welding process, the real-time acquired raw temperature data and features are extracted to obtain key morphological parameters of the molten pool: the maximum transverse dimension of the molten pool, the longitudinal penetration depth of the molten pool, the surface curvature of the molten pool, and the volume of the molten pool. Then, a mapping relationship between the feature parameters and the morphological state of the molten pool is established through a BP neural network to identify the morphology of the molten pool in real time.
[0019] A welding system for feedback-controlled molten pool morphology of molybdenum-rhenium alloy, comprising: The modeling module is used to establish a welding temperature and time distribution model for the molybdenum-rhenium alloy welding area, deduce the temperature change law of the welding area based on the characteristic parameters of the molybdenum-rhenium alloy welded parts, monitor the morphology of the molten pool weld area in real time, and control the heating process using a feedback mechanism. The monitoring module is used to input heat source using a dual-pulse heat source control strategy with asymmetric waveform. Based on the real-time monitoring of the internal morphology and temperature data of the molten pool during the welding process, it obtains the overall temperature field distribution on the surface of the molten pool, adjusts the temperature at areas with uneven temperature distribution, and controls the temperature of the molten pool. The prediction module is used to predict the residual thermal stress caused by welding in real time based on the molybdenum-rhenium alloy material itself, and to perform closed-loop feedback control of the stress level in the welding area through temperature adjustment. The adjustment module is used to achieve closed-loop feedback adjustment of the morphology of the molybdenum-rhenium alloy molten pool during welding, based on the welding temperature and time distribution model and the control of the molten pool temperature and the stress level in the welding zone.
[0020] A terminal device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the method.
[0021] A computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of the method.
[0022] Compared with the prior art, the present invention has the following beneficial effects: This invention provides a welding method for feedback-regulated molybdenum-rhenium alloy molten pool morphology. The method involves establishing a welding temperature and time distribution model to deduce temperature variation patterns; then, acquiring molten pool temperature and morphology data using an infrared-thermocouple coordinated temperature measurement system; and dynamically adjusting heating time, cooling rate, and heat source parameters using a PID algorithm and an asymmetric dual-pulse heat source strategy to control the molten pool temperature within a set range, while simultaneously predicting and regulating residual thermal stress. Finally, based on the welding temperature and time distribution model and the control of molten pool temperature and welding zone stress levels, a closed-loop feedback regulation of the molybdenum-rhenium alloy molten pool morphology is achieved during the welding process. This invention achieves real-time monitoring and control of the molten pool temperature through feedback regulation. It combines temperature field prediction with feedback control and algorithm verification throughout the entire process, linking molten pool morphology control with thermal stress. This enables multi-dimensional closed-loop feedback control of temperature field, pulse waveform, morphology prediction, and thermal stress during molybdenum-rhenium alloy welding, ensuring high-quality bonding of the weld joint. It significantly improves the bonding strength between the base material and the weld in the molybdenum-rhenium alloy welding zone, reduces crack initiation, and enhances weld fusion consistency and mechanical properties. Oxygen-free welding can be achieved in vacuum or protective atmospheres, providing reliable support for the manufacture of high-strength, high-temperature resistant molybdenum-rhenium alloy components. It is applicable to 1-10mm thick molybdenum-rhenium alloy components and high-temperature, high-strength precision components in aerospace, nuclear reactors, and other fields, possessing broad application prospects.
[0023] Furthermore, by establishing a temperature field distribution model and introducing an asymmetric pulse heat source control strategy combined with infrared-thermocouple synergistic temperature measurement, real-time monitoring and feedback adjustment of the temperature and morphology of the molybdenum-rhenium alloy molten pool can be achieved. This precisely matches the high melting point and easy oxidation characteristics of the molybdenum-rhenium alloy, avoiding excessive melting or insufficient fusion of the molten pool.
[0024] Furthermore, by using a PID control algorithm to adjust the heat source power in a closed loop and rapidly correcting the heat input based on real-time feedback of the molten pool morphology, common problems in refractory alloy welding, such as element burn-off and molten pool instability, can be effectively suppressed.
[0025] Furthermore, by connecting thermal stress prediction after the molten pool morphology meets the standards, the quality of the molybdenum-rhenium alloy molten pool and the subsequent stress state can be coordinated simultaneously, reducing the risk of cracks caused by thermal stress concentration at the weld joint. Attached Figure Description
[0026] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0027] Figure 1 This is a flowchart of the welding method for feedback-adjusted molybdenum-rhenium alloy molten pool morphology according to the present invention.
[0028] Figure 2 This is a heat source path diagram for the molybdenum-rhenium alloy welding process of the present invention.
[0029] Figure 3 This is a crystal orientation distribution diagram of the molybdenum-rhenium alloy welding zone of the present invention.
[0030] Figure 4 This is a topographical diagram of the molybdenum-rhenium alloy welding zone of the present invention.
[0031] Figure 5 This is a schematic diagram of a welding system for feedback adjustment of the molten pool morphology of molybdenum-rhenium alloy, according to a preferred embodiment of the present invention.
[0032] Figure 6 This is a schematic diagram of the electronic device structure according to a preferred embodiment of the present invention. Detailed Implementation
[0033] The following description, in conjunction with the accompanying drawings, illustrates exemplary embodiments of this application, including various details to aid understanding. These should be considered merely exemplary. Therefore, those skilled in the art will recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of this application. Similarly, for clarity and brevity, descriptions of well-known functions and structures are omitted in the following description.
[0034] Obviously, the described embodiments are only some, not all, of the embodiments in this application. All other embodiments obtained by those skilled in the art based on the embodiments in this application without inventive effort are within the scope of protection of this application.
[0035] It should be noted that the terminals involved in the embodiments of this application may include, but are not limited to, mobile phones, personal digital assistants (PDAs), wireless handheld devices, tablet computers, personal computers (PCs), MP3 players, MP4 players, wearable devices (e.g., smart glasses, smartwatches, smart bracelets), smart home devices, and other smart devices.
[0036] Furthermore, the term "and / or" in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.
[0037] The present invention will now be described in further detail with reference to the accompanying drawings: See Figure 1 This invention provides a welding method for feedback-controlled adjustment of the morphology of a molybdenum-rhenium alloy molten pool, specifically including the following steps: S1: First, establish a welding temperature and time distribution model for the molybdenum-rhenium alloy welding area, and deduce the temperature change law of the welding area based on the characteristic parameters of the welded parts.
[0038] S2: Based on the temperature change pattern of the welding area derived in S1, the morphology of the weld pool is monitored in real time and the heating process is controlled by a feedback mechanism to avoid defects caused by uneven temperature of the weld pool.
[0039] S3: During the welding process, a dual-pulse heat source control strategy with asymmetrical waveforms is adopted. Feedback control of the heat source input is achieved based on different amplitudes and frequencies, such as... Figure 2 As shown.
[0040] S4: During the welding process, an infrared-thermocouple coordinated temperature measurement system is used. The thermocouple sensor is placed close to the periphery of the molten pool to accurately collect local temperature data. The infrared thermometer receives the infrared energy radiated from the molten pool and monitors the internal morphology and temperature data of the molten pool in real time. The molten pool morphology is as follows: Figure 4 As shown, the overall temperature field distribution on the surface of the molten pool is calculated by combining Planck's law. The data is then supplemented and corrected by a fusion algorithm to calculate the error between the actual temperature and the set temperature.
[0041] S5: To address the temperature error calculated in real time in S4, a PID feedback control algorithm is used to adjust the temperature output at points of uneven temperature distribution, keeping the molten pool temperature within the set range to avoid overheating and overcooling, thus achieving precise temperature control closed-loop feedback regulation.
[0042] S6: During the welding process, the residual thermal stress caused by welding is predicted in real time based on the material itself. By adjusting the temperature, the stress level in the welding area is controlled to be lower than the set fatigue failure threshold, forming a closed-loop feedback control.
[0043] S7: Based on the control of the molten pool temperature and the stress level in the welding zone, the thermodynamic temperature field of the welding zone is optimized to reduce stress concentration, thermal distortion, and the appearance of brittle phases. The crystal orientation distribution in the welding zone is as follows: Figure 3 As shown.
[0044] After welding, a staged annealing and cooling process is adopted, including a rapid cooling stage, a holding stage, and a slow annealing stage. First, the temperature is rapidly reduced, and then the microstructure of the molybdenum-rhenium alloy is controlled at a constant temperature. Finally, it is slowly cooled to room temperature to avoid the molybdenum-rhenium alloy welded parts remaining in the high-temperature brittle range for a long time.
[0045] Preferably, the temperature distribution model of the present invention combines infrared thermal imaging system and thermocouple sensor array for collaborative sampling, and uses finite element software to construct temperature distribution map.
[0046] Preferably, the dual-pulse heat source power control strategy of asymmetric waveform automatically adjusts the flow rate of the main pulse (determining the penetration depth and penetration width) and the auxiliary pulse (suppressing crack formation and refining grains) according to the weldment structure type, material properties, welding gap thickness and heat accumulation during the heating process. The pulse heat source is equipped with a modulation algorithm based on an empirical database.
[0047] Preferably, the real-time morphology monitoring method used in the welding process involves collecting data on the melting effect caused by temperature changes and energy input in a unit area, and automatically determining whether the welding has reached the target fusion standard by combining the established welding temperature and time distribution model.
[0048] Preferably, a temperature range control strategy is implemented by real-time monitoring of the molten pool temperature, and a closed loop is formed by using PID feedback control and an infrared thermocouple-assisted temperature measurement system to regulate the heat source output.
[0049] Preferably, this process is applicable to molybdenum-rhenium alloy structural parts and precision instrument components with a thickness range of 1 to 10 mm, and can also be performed in an oxygen-free welding operation under a protective atmosphere.
[0050] The present invention will be further described in detail below through specific embodiments: Example 1: This invention is based on a closed-loop feedback regulation mechanism and is mainly applicable to high-strength and high-temperature resistant structural components of molybdenum-rhenium alloy, key components of semiconductor precision instruments, and structural components of nuclear reactors. The thickness range is 1 to 10 mm. It can also be used for oxygen-free welding operations in vacuum or protective atmosphere.
[0051] S1: First, welding temperature and time distribution models were established for the molybdenum-rhenium alloy welding area. Based on the shape, structure, thermal conductivity, and coefficient of thermal expansion of the molybdenum-rhenium alloy weldment, the temperature change law of the welding area was deduced. According to the deduced temperature change law of the welding area, an infrared-thermocouple combined temperature measurement system was used to monitor the temperature of the molten pool welding area in real time. A three-dimensional map was drawn based on the real-time monitoring data to ensure data accuracy.
[0052] The method for constructing the welding temperature and time distribution model is as follows: Based on the three-dimensional transient heat conduction theory composed of the temperature field and time of the molybdenum-rhenium alloy molten pool, the latent heat of phase change is equivalent to the specific heat. A Gaussian surface heat source is used as the heat input, and the initial condition is set to room temperature. The upper surface of the molybdenum-rhenium alloy weld is considered as the mixing boundary. At the same time, an asymmetric double pulse heat source and convective heat transfer are applied. The other surfaces of the workpiece are only considered for convective and radiative heat dissipation, and external heat source input is not considered. The normal heat flux on the symmetry plane is zero. Then, the transient heat conduction equation is solved to obtain the welding temperature and time distribution model of the weldment molten pool.
[0053] Based on the properties of molybdenum-rhenium alloy, temperature changes in the molten pool are monitored and predicted in real time by combining theoretical analysis with a welding temperature and time distribution model, and a temperature distribution map is constructed.
[0054] Depending on the shape of the workpiece, the heat conduction path, energy distribution, and heat dissipation path can be easily affected. Traditional processes have too many limitations and find it difficult to achieve multi-system synergy, ensuring uniform temperature distribution and controllable morphology within the weld pool while reducing thermal stress that could lead to weak bonding between the weld and the base material. A non-contact infrared thermal imaging system is installed within the weld pool to collect data, while multiple sets of high-precision thermocouple sensors are used for contact measurement of the weld pool temperature, enabling synchronous acquisition of temperature change data.
[0055] The collected data is integrated using a three-dimensional interpolation algorithm to create a three-dimensional map. The heat transfer process is then calculated using finite element simulation software to accurately predict the temperature field distribution and thermal stress changes.
[0056] By combining the shape and size of the molybdenum-rhenium alloy welded parts, the heat source model is simplified to a point heat source. The heat conduction in three directions (X, Y, Z) is recorded to establish a heat source model inside the molten pool, accurately characterizing the temperature distribution during the welding process. At the same time, it provides data support for subsequent PID feedback algorithms and asymmetric heat source control.
[0057] The heat source model inside the molten pool adopts the Gaussian surface heat source model, which superimposes the voltage, current, welding speed and heat source radius of the asymmetric double pulse heat source into the heat source in the form of a time function, so as to realize the Gaussian distribution of heat flux density in space and the periodic change in time according to the asymmetric double pulse law.
[0058] Based on the asymmetric double-pulse time periodic function, the Gaussian distribution characteristics of the heat source in space are introduced to make the heat source calculation conform to the heat transfer process in the actual welding process.
[0059] S2: Based on the data given by the above welding temperature and time distribution model, the molten pool temperature is always controlled within the set value range to avoid the generation of thermal stress due to uneven temperature. At the same time, the total energy input of heat during this stage is calculated.
[0060] During the welding process, a dual-pulse heat source power control strategy with asymmetric waveforms is adopted. The pulses are combined with the temperature distribution calculated by the upper-level PID feedback control algorithm. In different molten pool temperature zones, different amplitudes, frequencies and waveforms are used to adjust the heating time and cooling rate (temperature and flow rate) output, so that the molten pool temperature is always controlled within the set value range, avoiding overheating and overcooling, and realizing precise temperature control closed-loop feedback regulation.
[0061] Unlike traditional processes, this invention employs asymmetric dual-waveform control of the heat source power. The heating method is as follows: First, a large amplitude waveform is used to determine the welding point location within a larger heat source power range, and the temperature is rapidly increased; second, a smaller amplitude waveform is used to determine the temperature within a smaller heat source power range to achieve uniform and stable temperature within the molten pool, maintain the internal state of the molten pool to promote the fusion of the molybdenum-rhenium alloy weld, and suppress grain growth behavior in the heat-affected zone.
[0062] The system automatically adjusts the size and frequency of the wave peaks within a specified range in real time to address uneven temperature distribution within the molten pool, thereby regulating the heat source power. This feedback regulation can effectively solve problems such as poor weld joint, incomplete welds, and deformation of the base material that are common in traditional welding processes.
[0063] S3: To address the device packaging structure warping and solder joint fatigue caused by residual thermal stress exceeding the threshold during the welding process, this invention predicts the distribution trend of residual thermal stress during welding based on the material's thermal expansion coefficient and elastic modulus parameters, combined with the device's geometry.
[0064] During the welding heating stage, the displacement and temperature change data of the device surface are collected in real time, and the residual thermal stress is estimated simultaneously to predict whether the stress exceeds the threshold. The feedback enables self-adjustment of the heat source input, controlling the stress level in the welding area below the set fatigue failure threshold, thus achieving precise control of welding residual stress.
[0065] S4: During the welding process, the raw temperature data and features collected in real time are extracted to obtain key morphological parameters of the molten pool: weld width (maximum lateral dimension of the molten pool), weld depth (longitudinal penetration depth of the molten pool), molten pool surface curvature, and molten pool volume. Then, a mapping relationship between the feature parameters and the molten pool morphological state (stable / overheated / undercooled) is established through a BP neural network to achieve real-time and accurate identification of the molten pool morphology.
[0066] Based on the detected molten pool morphology parameters, the core of dynamic morphology control is to stabilize the molten pool morphology within the target range by adjusting the welding heat source input parameters, namely pulse peak power, welding speed and pulse duty cycle.
[0067] S5: Based on the welding temperature and time distribution model, the thermodynamic temperature field of the welding zone is optimized in a coordinated manner, and the temperature distribution difference is dynamically analyzed to achieve the heat conduction balance between the base material and the workpiece in the welding zone, reduce the generation of welding defects, and further reduce the temperature difference by combining the thermal coupling optimization method to achieve precise control of the welding zone temperature through closed-loop feedback.
[0068] After welding, a stepped heat treatment cooling curve is used for control, including a rapid cooling stage, a heat holding and stress control stage, and a slow annealing stage. This effectively improves the grain size stability and cycle life of the weldment. Specific temperature gradients and time settings are determined based on the thermal stability of the selected molybdenum-rhenium alloy. Rapid cooling stage: cooling rate 0.5~3℃ / min; holding time 30~90min. This inhibits rapid grain growth and preserves sintering density.
[0069] Thermal stress control stage: Cooling rate 1~5℃ / min; holding time 20~60min. This releases grain boundary stress and prevents cracking in the low-temperature stage.
[0070] Slow annealing stage: The furnace is allowed to cool naturally at a rate ≤10℃ / min. The temperature is slowly reduced to room temperature to eliminate residual thermal stress.
[0071] Example 2: The present invention also provides a welding system for feedback-controlled adjustment of the molten pool morphology of molybdenum-rhenium alloy, such as... Figure 5 As shown, the system includes: a modeling module, a monitoring module, a prediction module, and a regulation module.
[0072] The modeling module is used to establish a welding temperature and time distribution model for the molybdenum-rhenium alloy welding area, deduce the temperature change law of the welding area based on the characteristic parameters of the molybdenum-rhenium alloy welded parts, monitor the morphology of the molten pool weld area in real time, and control the heating process using a feedback mechanism. The monitoring module is used to input heat source using a dual-pulse heat source control strategy with asymmetric waveform. Based on the real-time monitoring of the internal morphology and temperature data of the molten pool during the welding process, it obtains the overall temperature field distribution on the surface of the molten pool, adjusts the temperature at areas with uneven temperature distribution, and controls the temperature of the molten pool. The prediction module is used to predict the residual thermal stress caused by welding in real time based on the molybdenum-rhenium alloy material itself, and to perform closed-loop feedback control of the stress level in the welding area through temperature adjustment. The adjustment module is used to achieve closed-loop feedback adjustment of the morphology of the molybdenum-rhenium alloy molten pool during welding, based on the welding temperature and time distribution model and the control of the molten pool temperature and the stress level in the welding zone.
[0073] It is understood that the welding system for feedback regulation of molybdenum-rhenium alloy molten pool morphology provided by the present invention corresponds to the welding method for feedback regulation of molybdenum-rhenium alloy molten pool morphology provided in the foregoing embodiments. The relevant technical features of the welding system for feedback regulation of molybdenum-rhenium alloy molten pool morphology can be referred to the relevant technical features of the welding method for feedback regulation of molybdenum-rhenium alloy molten pool morphology, and will not be repeated here.
[0074] Another object of the present invention is to provide an electronic device, such as... Figure 6 As shown, it includes a memory, a processor, and a computer program stored in the memory and executable on the processor, the processor performing the steps of the welding method for feedback-adjusted molybdenum-rhenium alloy molten pool morphology.
[0075] The welding method for adjusting the morphology of the molybdenum-rhenium alloy molten pool via feedback includes the following steps: A welding temperature and time distribution model was established for the welding area of molybdenum-rhenium alloy. The temperature change law of the welding area was deduced based on the characteristic parameters of the molybdenum-rhenium alloy welded parts. The morphology of the weld pool was monitored in real time and the heating process was controlled by a feedback mechanism. A dual-pulse heat source control strategy with asymmetric waveform is adopted for heat source input. Based on the real-time monitoring of the internal morphology and temperature data of the molten pool during the welding process, the overall temperature field distribution on the surface of the molten pool is obtained. Temperature adjustment is performed at the points of uneven temperature distribution to control the temperature of the molten pool. Based on the real-time prediction of residual thermal stress caused by welding by the molybdenum-rhenium alloy material itself, the stress level in the welding area is controlled by closed-loop feedback through temperature regulation. Based on the welding temperature and time distribution model, and combined with the control of the molten pool temperature and the stress level in the welding zone, a closed-loop feedback adjustment of the molten pool morphology of the molybdenum-rhenium alloy during the welding process is achieved.
[0076] A fourth objective of this invention is to provide a computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of the welding method for feedback-adjusted molybdenum-rhenium alloy molten pool morphology.
[0077] The welding method for adjusting the morphology of the molybdenum-rhenium alloy molten pool via feedback includes the following steps: A welding temperature and time distribution model was established for the welding area of molybdenum-rhenium alloy. The temperature change law of the welding area was deduced based on the characteristic parameters of the molybdenum-rhenium alloy welded parts. The morphology of the weld pool was monitored in real time and the heating process was controlled by a feedback mechanism. A dual-pulse heat source control strategy with asymmetric waveform is adopted for heat source input. Based on the real-time monitoring of the internal morphology and temperature data of the molten pool during the welding process, the overall temperature field distribution on the surface of the molten pool is obtained. Temperature adjustment is performed at the points of uneven temperature distribution to control the temperature of the molten pool. Based on the real-time prediction of residual thermal stress caused by welding by the molybdenum-rhenium alloy material itself, the stress level in the welding area is controlled by closed-loop feedback through temperature regulation. Based on the welding temperature and time distribution model, and combined with the control of the molten pool temperature and the stress level in the welding zone, a closed-loop feedback adjustment of the molten pool morphology of the molybdenum-rhenium alloy during the welding process is achieved.
[0078] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.
[0079] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.
[0080] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.
[0081] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.
[0082] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.
Claims
1. A welding method for feedback-controlled molten pool morphology of molybdenum-rhenium alloy, characterized in that, include: A welding temperature and time distribution model was established for the welding area of molybdenum-rhenium alloy. The temperature change law of the welding area was deduced based on the characteristic parameters of the molybdenum-rhenium alloy welded parts. The morphology of the weld pool was monitored in real time and the heating process was controlled by a feedback mechanism. A dual-pulse heat source control strategy with asymmetric waveform is adopted for heat source input. Based on the real-time monitoring of the internal morphology and temperature data of the molten pool during the welding process, the overall temperature field distribution on the surface of the molten pool is obtained. Temperature adjustment is performed at the points of uneven temperature distribution to control the temperature of the molten pool. Based on the real-time prediction of residual thermal stress caused by welding by the molybdenum-rhenium alloy material itself, the stress level in the welding area is controlled by closed-loop feedback through temperature regulation. Based on the welding temperature and time distribution model, and combined with the control of the molten pool temperature and the stress level in the welding zone, a closed-loop feedback adjustment of the molten pool morphology of the molybdenum-rhenium alloy during the welding process is achieved.
2. The welding method for feedback-controlled molybdenum-rhenium alloy molten pool morphology according to claim 1, characterized in that, The method for constructing the welding temperature and time distribution model is as follows: Based on the three-dimensional transient heat conduction theory of temperature field and time composition in the welding zone of molybdenum-rhenium alloy molten pool, the transient heat conduction equation is solved according to the boundary and initial conditions by using the equivalent specific heat of latent heat of phase change and a Gaussian surface heat source as heat input, thereby obtaining the temperature and time distribution model of molybdenum-rhenium alloy molten pool welding.
3. The welding method for feedback-controlled molybdenum-rhenium alloy molten pool morphology according to claim 1, characterized in that, The method of controlling the heating process using a feedback mechanism is as follows: During the welding process, a dual-pulse heat source power control strategy with asymmetric waveform is used to heat the weld pool area. The pulse is combined with the upper-level PID feedback control algorithm to calculate the temperature distribution. In different weld pool temperature zones, different amplitudes, frequencies and waveforms are used to adjust the heating time and cooling rate output, so that the temperature of the weld pool area is always controlled within the set value range.
4. The welding method for feedback-controlled molybdenum-rhenium alloy molten pool morphology according to claim 1, characterized in that, The characteristic parameters of molybdenum-rhenium alloy welded parts include shape, thermal conductivity, and coefficient of thermal expansion.
5. The welding method for feedback-adjusted molybdenum-rhenium alloy molten pool morphology according to claim 1, characterized in that, The method for monitoring the overall temperature field distribution on the surface of the molten pool during welding is as follows: A non-contact infrared thermometer is installed inside the molten pool to receive the infrared energy radiated from the molten pool and monitor the morphology and temperature data of the molten pool in real time. At the same time, a thermocouple sensor is installed to measure the temperature of the molten pool in contact and collect the temperature change data of the molten pool synchronously. Based on the temperature change data of the molten pool, the overall temperature field distribution on the surface of the molten pool is calculated using Planck's law.
6. The welding method for feedback-adjusted molybdenum-rhenium alloy molten pool morphology according to claim 5, characterized in that, The method for converting Planck's law to the overall temperature field distribution on the surface of the molten pool is as follows: Based on the shape and size of the molybdenum-rhenium alloy welded parts, the heat source in the molten pool is simplified to a point heat source. The heat conduction in the X, Y and Z directions is recorded to establish a heat source model inside the molten pool and characterize the temperature distribution during the welding process. The heat source model inside the molten pool adopts the Gaussian surface heat source model.
7. The welding method for feedback-controlled molybdenum-rhenium alloy molten pool morphology according to claim 1, characterized in that, The real-time monitoring method for the internal morphology of the molten pool during welding is as follows: During the welding process, the real-time acquired raw temperature data and features are extracted to obtain key morphological parameters of the molten pool: the maximum transverse dimension of the molten pool, the longitudinal penetration depth of the molten pool, the surface curvature of the molten pool, and the volume of the molten pool. Then, a mapping relationship between the feature parameters and the morphological state of the molten pool is established through a BP neural network to identify the morphology of the molten pool in real time.
8. A welding system for feedback-controlled molten pool morphology of molybdenum-rhenium alloy, characterized in that, include: The modeling module is used to establish a welding temperature and time distribution model for the molybdenum-rhenium alloy welding area, deduce the temperature change law of the welding area based on the characteristic parameters of the molybdenum-rhenium alloy welded parts, monitor the morphology of the molten pool weld area in real time, and control the heating process using a feedback mechanism. The monitoring module is used to input heat source using a dual-pulse heat source control strategy with asymmetric waveform. Based on the real-time monitoring of the internal morphology and temperature data of the molten pool during the welding process, it obtains the overall temperature field distribution on the surface of the molten pool, adjusts the temperature at areas with uneven temperature distribution, and controls the temperature of the molten pool. The prediction module is used to predict the residual thermal stress caused by welding in real time based on the molybdenum-rhenium alloy material itself, and to perform closed-loop feedback control of the stress level in the welding area through temperature adjustment. The adjustment module is used to achieve closed-loop feedback adjustment of the morphology of the molybdenum-rhenium alloy molten pool during welding, based on the welding temperature and time distribution model and the control of the molten pool temperature and the stress level in the welding zone.
9. A terminal device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 7.
10. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 7.