Oxygen-free silver-containing copper rod heat treatment process parameter optimization method and system

Abstract

The invention relates to the technical field of copper rod production, in particular to an oxygen-free silver-containing copper rod heat treatment process parameter optimization method and system.The method comprises the steps that microstructure characteristics and copper rod characteristic parameters of an oxygen-free silver-containing copper rod to be subjected to heat treatment are obtained; the microstructure characteristics and the copper rod characteristic parameters serve as positioning conditions, matching positioning is conducted in a pre-constructed heat treatment process library, an initial heat treatment process parameter set is determined, and heat treatment is conducted on the oxygen-free silver-containing copper rod according to the initial heat treatment process parameter set; in the heat treatment process, a heat treatment characteristic parameter set of the oxygen-free silver-containing copper rod is collected in real time; and in response to the condition that at least one heat treatment feature in the heat treatment feature parameter set does not reach a preset target feature index within a preset time, calculating deviation values of all the heat treatment features which do not reach the standard, and converting the deviation values into heat treatment deviation vectors. The microstructure change of the material in the heat treatment process can be responded in real time, and dynamic adjustment of process parameters is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of copper rod production, and in particular to a method and system for optimizing heat treatment process parameters of an oxygen-free silver-containing copper rod. Background Art

[0002] Oxygen-free silver-containing copper rods are high-performance conductive materials and are widely used in superconducting equipment, precision electronic devices, aerospace cables and other fields; their mechanical properties and conductive properties directly depend on the microstructural characteristics of the material after heat treatment.

[0003] Heat treatment is an important processing technology that changes the microstructure and properties of metal materials by heating, insulating and cooling them. For oxygen-free silver-containing copper rods, a reasonable heat treatment process can refine the grains, improve the grain boundary characteristics, and adjust the distribution of alloying elements (such as silver), thereby significantly improving the performance of the copper rod, such as enhancing its strength, toughness, and fatigue resistance, while also ensuring its good electrical conductivity and thermal stability.

[0004] Existing heat treatment process parameters for oxygen-free silver-containing copper rods are often developed based on experience or universal standards. However, due to differences in microstructural characteristics and copper rod characteristic parameters, uniform heat treatment process parameters may not achieve optimal treatment results. For example, copper rods with different silver contents have different requirements for parameters such as temperature, holding time, and cooling rate during the heat treatment process. Using the same empirical heat treatment process parameters may result in suboptimal performance for some copper rods. At the same time, in the actual heat treatment process, factors such as the operating status of the heat treatment equipment, the microstructure of the raw materials, and subtle differences in composition may cause the heat treatment characteristic parameters to deviate from expectations; but once the existing heat treatment process parameters are determined, it is difficult to adjust them in real time during the heat treatment process; for example, when it is found that the rate of change of the microstructure of the copper rod does not meet expectations during the insulation process, it is impossible to adjust the insulation time or other process parameters in time, which may affect the performance of the final copper rod. Summary of the Invention

[0005] The present invention provides a method and system for optimizing heat treatment process parameters of an oxygen-free silver-containing copper rod, which can respond in real time to microstructural changes of a material during heat treatment and achieve dynamic adjustment of process parameters, and can effectively solve the problems in the background technology.

[0006] In order to achieve the above objectives, in a first aspect, the present invention provides a method for optimizing process parameters of heat treatment of an oxygen-free silver-containing copper rod, comprising: Obtaining the microstructural characteristics and characteristic parameters of the oxygen-free silver-containing copper rod to be heat-treated; Using the microstructural features and the copper rod characteristic parameters as positioning conditions, matching and positioning are performed in a pre-built heat treatment process library to determine an initial heat treatment process parameter set, and heat treating the oxygen-free silver-containing copper rod based on the initial heat treatment process parameter set; During the heat treatment process, the heat treatment characteristic parameter set of the oxygen-free silver-containing copper rod is collected in real time; In response to at least one heat treatment feature in the heat treatment feature parameter set failing to reach a preset target feature index within a preset time, calculating deviation values of all heat treatment features that fail to reach the target index and converting them into a heat treatment deviation vector; Based on the heat treatment deviation vector, the initial heat treatment process parameter set is regulated to obtain an optimal heat treatment process parameter set, and the oxygen-free silver-containing copper rod is heat treated accordingly.

[0007] In combination with the first aspect, in one possible design, the microstructural characteristics include at least grain size, grain morphology, and grain boundary characteristics; The copper rod characteristic parameters include at least specification characteristics and composition characteristics.

[0008] In combination with the first aspect, in one possible design, the preset time is a dynamic response time window, which satisfies the following calculation formula: ; Among them, t preset represents the preset time; d represents the real-time grain size; K0 represents the grain growth rate constant, which is a material intrinsic parameter that characterizes the grain boundary migration rate of the Ag-Cu system; Q represents the grain boundary migration activation energy, which reflects the inhibitory effect of silver atoms on the recrystallization process of the copper matrix; R represents the gas constant, which is a universal constant in thermodynamic calculations; T represents the real-time temperature of the copper rod surface in the heat treatment furnace; α represents the thermal hysteresis compensation factor, which is used to correct the deviation effect of temperature field fluctuation on grain growth prediction; ΔD represents the absolute difference between the current grain size and the target value; D target Indicates the target grain size, which is the ideal grain diameter set according to product performance requirements.

[0009] In combination with the first aspect, in one possible design, the initial heat treatment process parameter set includes at least heating temperature, holding time and cooling rate.

[0010] In combination with the first aspect, in a possible design, the heat treatment characteristic parameter set includes temperature field characteristic parameters, microstructure dynamic parameters, physical property parameters, and process control parameters.

[0011] In combination with the first aspect, in a possible design, the temperature field characteristic parameter includes at least one of a temperature gradient distribution and a temperature change rate; The microstructure dynamic parameter includes at least one of grain size, grain boundary migration rate and silver element distribution characteristics; The physical performance parameter includes at least one of residual stress field, dynamic value of electrical conductivity and hardness distribution characteristics; The process control parameters include at least one of the oxygen content in the holding stage, equipment power, quenching medium flow rate, and quenching medium temperature.

[0012] In conjunction with the first aspect, in a possible design, the heat treatment process library is used to store initial heat treatment process parameter sets under different combinations of microstructure features and copper rod characteristic parameters; The heat treatment process library retrieves an initial heat treatment process parameter set that matches the input copper rod characteristic parameters based on a preset indexing method.

[0013] In combination with the first aspect, in a possible design, the indexing method preset in the heat treatment process library includes According to the specification characteristics of the copper rod to be processed, an initial heat treatment process parameter set that matches the specification characteristics is selected and marked as a first-order initial heat treatment process parameter set; Setting matching weights for grain size, grain morphology, and grain boundary characteristics, respectively, and calculating the similarity between the copper rod to be processed and all the first-order initial heat treatment process parameter sets; The first-order initial heat treatment process parameter set with the highest similarity is used as the initial heat treatment process parameter set for the copper rod to be processed.

[0014] In conjunction with the first aspect, in one possible design, the method for collecting the temperature gradient distribution in the temperature field characteristic parameters includes: A preset number of temperature sensors are arranged in the axial direction of the copper rod in the heat treatment furnace; Based on the preset frequency, collect the monitoring temperature of each temperature sensor; Based on the collected monitoring temperature, the axial temperature gradient of the copper rod is calculated.

[0015] In a second aspect, the present invention further provides a system for optimizing process parameters for heat treatment of an oxygen-free silver-containing copper rod, comprising: A parameter acquisition module is used to obtain the microstructure characteristics and characteristic parameters of the oxygen-free silver-containing copper rod to be heat-treated; The parameter matching and positioning module is used to use the microstructure characteristics and copper rod characteristic parameters as positioning conditions, match and locate in the pre-built heat treatment process library, and determine the initial heat treatment process parameter set; A real-time acquisition module is used to collect the heat treatment characteristic parameter set of the oxygen-free silver-containing copper rod in real time during the heat treatment process; a deviation calculation module, configured to determine whether at least one heat treatment characteristic in the heat treatment characteristic parameter set fails to meet a preset target characteristic index within a preset time period; if so, calculate the deviation values of all the heat treatment characteristics that fail to meet the target index and convert them into a heat treatment deviation vector; The parameter control module is used to control the initial heat treatment process parameter set based on the heat treatment deviation vector obtained by the deviation calculation module to obtain the optimal heat treatment process parameter set, and use it to heat treat the oxygen-free silver-containing copper rod.

[0016] The technical solution of the present invention can achieve the following technical effects: by obtaining the microstructural characteristics and characteristic parameters of the oxygen-free silver-containing copper rod to be heat-treated, and using these as positioning conditions to match and locate the initial heat treatment process parameter set in the heat treatment process library, the previous method of formulating process parameters based on experience or general standards is changed, and a more targeted heat treatment process can be formulated for copper rods with different characteristics, avoiding the problem that unified parameters cannot achieve the best treatment effect, and improving the consistency and reliability of the copper rod performance; the heat treatment characteristic parameter set is collected in real time during the heat treatment process, and when it is found that at least one heat treatment characteristic does not meet the preset target characteristic index, the deviation value can be calculated and converted into a heat treatment deviation vector, and then the initial heat treatment process parameter set is adjusted to obtain the optimal heat treatment process parameter set, which can effectively deal with the situation where the heat treatment characteristic parameters deviate from expectations due to factors such as equipment operating status, raw material microstructure and subtle composition differences during the heat treatment process, thereby ensuring that the performance of the final copper rod is not affected; In summary, this method realizes the bidirectional feedback of microstructure evolution and process parameters through the coupled optimization of real-time monitoring-dynamic decision-making-closed-loop control, so that the segregation suppression of silver elements and the grain boundary migration rate are automatically balanced; at the same time, the multi-parameter coupling deviation is compressed to the process tolerance range, and the cross-scale compensation mechanism is triggered in the event of sudden working conditions, achieving a strong robust effect of self-digestion of dynamic disturbances. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0018] Figure 1 1. It is a logic flow chart of the method for optimizing process parameters of heat treatment of oxygen-free silver-containing copper rod in the present invention; Figure 2 This is a structural block diagram of the process parameter optimization system for heat treatment of oxygen-free silver-containing copper rods in the present invention. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0020] The present application is described below in conjunction with the accompanying drawings.

[0021] like Figure 1 As shown, the method for optimizing process parameters of heat treatment of oxygen-free silver-containing copper rod of the present invention specifically comprises the following steps: Step S1, obtaining the microstructure characteristics and characteristic parameters of the oxygen-free silver-containing copper rod to be heat-treated; Step S2: using the microstructural features and the copper rod characteristic parameters as positioning conditions, matching and positioning are performed in a pre-built heat treatment process library to determine an initial heat treatment process parameter set, and heat treating the oxygen-free silver-containing copper rod based on the initial heat treatment process parameter set; Step S3: During the heat treatment process, a heat treatment characteristic parameter set of the oxygen-free silver-containing copper rod is collected in real time; Step S4: in response to at least one heat treatment characteristic in the heat treatment characteristic parameter set failing to reach a preset target characteristic index within a preset time, calculating deviation values of all heat treatment characteristics that fail to reach the target index and converting them into a heat treatment deviation vector; Step S5: Based on the heat treatment deviation vector, the initial heat treatment process parameter set is regulated to obtain an optimal heat treatment process parameter set, and the oxygen-free silver-containing copper rod is heat treated accordingly.

[0022] In this embodiment, the traditional process relies on experience and universal standards, with fixed process parameters and a lack of flexibility. However, this method dynamically adjusts the process parameters by matching the microstructural features and copper rod characteristic parameters, combined with real-time collected heat treatment characteristic parameters, to form a closed-loop optimization system from "experience-driven" to "data-driven". This not only solves the problem of "one-size-fits-all" process parameters in traditional processes, but also achieves adaptive optimization of process parameters. Even in the face of complex material properties and equipment fluctuations, the process parameters can be automatically adjusted to the optimal state, forming an intelligent and adaptive heat treatment capability, so that the process is no longer limited to experience and standards, but has the ability to be intelligent and precise. By collecting heat treatment characteristic parameter sets in real time, combined with deviation value calculation and heat treatment deviation vector analysis, dynamic adjustment of process parameters can be achieved. Dynamic adjustment runs through the entire heat treatment process, rather than being limited to a fixed link. This transforms the originally static process into a dynamic process control, which can respond in real time to the microstructural changes of the material during the heat treatment process. For example, when the grain growth rate at a certain stage does not meet the expectation, the holding time or cooling rate can be adjusted immediately, avoiding the performance loss caused by delayed adjustment in traditional processes, making the process more precise and the performance of the final product more stable and excellent. By collecting and analyzing heat treatment characteristic parameters in real time and combining them with deviation vector calculation, process parameters can be globally regulated to ensure that process parameters at each stage have a positive impact on the final performance, achieving a leap from local optimization to global optimization. For example, if slow grain growth is detected during the holding stage, not only will the holding time be adjusted, but the parameters of the subsequent cooling stage will also be comprehensively considered to ensure the continuity and consistency of the entire heat treatment process. This global optimization capability ensures more balanced and excellent performance of the final product, avoiding overall performance shortcomings caused by local optimization. By obtaining the microstructural characteristics and characteristic parameters of the copper rod and combining them with the matching positioning of the heat treatment process library, the process parameters are transformed from "process-dependent" to "material property-driven", enabling the process parameters to better adapt to the differences in material properties. For example, copper rods with different silver contents have different requirements for temperature, holding time and cooling rate during heat treatment. This method can automatically adjust the process parameters according to the material properties, avoiding performance losses caused by a "one-size-fits-all" process.

[0023] In some embodiments of the present invention, the microstructural characteristics include at least grain size, grain morphology, and grain boundary characteristics; and the copper rod characteristic parameters include at least specification characteristics and composition characteristics.

[0024] Grain size refers to the average size of the grains in the copper rod material. Grain size has a significant impact on the material's strength, toughness, and conductivity. For example, fine grains generally improve the material's strength and toughness, but may have a certain impact on conductivity. The acquisition method uses metallographic microscopy. Samples of the copper rod to be heat-treated are taken. After grinding, polishing, and etching, the grain morphology is observed under a metallographic microscope at 100-500 times magnification. The average size of at least 50 grains is measured using image analysis software, or the average grain diameter is calculated using the intercept method to ensure statistical significance of the data. Grain morphology refers to the shape characteristics of grains, such as equiaxed, columnar, or lamellar. Grain morphology affects the distribution of grain boundaries and the mechanical properties of the material. Metallographic photographs or scanning electron microscope images are used to record the geometric shape of the grains (such as equiaxed, columnar, or irregular), surface roughness, and integrity of the grain boundaries. The presence and proportion of abnormal grains, including twins and coarse grains, are determined. Grain boundary characteristics include the clarity, continuity and migration rate of grain boundaries; using scanning electron microscopy combined with electron backscatter diffraction technology, the orientation difference of grain boundaries, the distribution of precipitated phases at grain boundaries, such as the segregation of silver elements at grain boundaries, as well as the continuity and cleanliness of grain boundaries, and whether there is an oxide film or impurity enrichment are analyzed.

[0025] The characteristic parameters of copper rod reflect the basic properties of the material. The specification characteristics include geometric parameters and previous processing technology; the composition characteristics include silver content and alloy element distribution. The specific methods for obtaining them are as follows: Geometric parameters: Use a vernier caliper or laser caliper to measure the diameter, length, cross-sectional shape and surface defects of the copper rod; Pre-processing technology: record the initial processing technology and deformation of the copper rod, because the processing history will affect the initial texture and residual stress state of the material; Silver content detection: Use inductively coupled plasma emission spectroscopy or X-ray fluorescence spectroscopy to perform elemental quantitative analysis on copper rod samples, accurately determine the mass fraction of silver and the content of impurity elements, and ensure that the composition meets the oxygen-free copper standard; Alloy element distribution: Use an electron probe or energy spectrometer to detect the uniformity of the distribution of silver elements in the copper matrix and determine whether there is segregation.

[0026] In this embodiment, the parameters obtained in step S1 directly reflect the individual characteristics of the oxygen-free silver-containing copper rod. The microstructural characteristics determine the potential of the material for grain refinement and grain boundary optimization during heat treatment. For example, a copper rod with initially coarse grains may require a higher heating temperature or a longer holding time to promote recrystallization. The characteristic parameters of the copper rod (especially the silver content and specifications) determine the thermodynamic behavior during heat treatment. For example, a copper rod with a high silver content requires a controlled cooling rate to avoid silver phase precipitation, which affects conductivity. Through precise detection methods, the limitations of traditional processes that rely on empirical parameters are broken, and input conditions are provided for subsequent data-driven process optimization, ensuring that the heat treatment solutions for the copper rods are tailored to the individual needs and improving the treatment effect from the source.

[0027] In some embodiments of the present invention, the microstructural features and characteristic parameters of the copper rod are matched and located with a pre-built heat treatment process library to determine an initial heat treatment process parameter set suitable for the copper rod, ensuring that the initial process parameters can adapt to the specific needs of the copper rod.

[0028] Among them, the heat treatment process library stores the heat treatment process parameter sets corresponding to different microstructural features and copper rod characteristic parameters. The data in the process library is generated through experimental verification, theoretical calculation or industrial experience accumulation, and is continuously improved through data analysis and optimization algorithms; specifically, it includes the initial heat treatment process parameter sets under different combinations of microstructural features and copper rod characteristic parameters, such as heating temperature, holding time, cooling rate, etc.; for example: a copper rod with a silver content of 0.1%, a grain size of 100μm, and a specification of 10mm in diameter, the corresponding initial process parameters may be a heating temperature of 800℃, a holding time of 60 minutes, and a cooling rate of 5℃ / min; a copper rod with a silver content of 0.3%, a grain size of 50μm, and a specification of 20mm in diameter, the corresponding initial process parameters may be a heating temperature of 850℃, a holding time of 90 minutes, and a cooling rate of 3℃ / min.

[0029] Specifically, the method for constructing a heat treatment process library is as follows: collect a large amount of heat treatment experimental data, actual production data and related theoretical research results of oxygen-free silver-containing copper rods under different combinations of microstructural characteristics and copper rod characteristic parameters; the data must cover the correspondence between various process parameters such as heating temperature, holding time, cooling rate and the final performance of the copper rod; systematically organize, analyze and classify the collected data; use technical means such as data mining and machine learning to extract valuable information from massive data, and construct a heat treatment process library with a certain logical structure and indexing method; the process library can quickly retrieve the matching heat treatment process information based on the input copper rod characteristic parameters.

[0030] More specifically, the microstructure characteristics and copper rod characteristic parameters are used as positioning conditions and matched with the data in the process library. The initial heat treatment process parameter set that matches the input data is output, including heating temperature, holding time, and cooling rate. The matching method "layered screening + weight matching" strategy ensures positioning accuracy. The specific implementation is as follows: First, eliminate process ranges that clearly do not match the specifications. For example, copper rods with diameters greater than 20 mm require a 20% or greater increase in holding time due to low heat conduction efficiency. Furthermore, process parameter ranges are limited based on compositional characteristics. For example, when the silver content is greater than 0.1%, the cooling rate must be ≤ 8°C / s to prevent the formation of Ag2Cu precipitation, which affects conductivity. Matching weights are set for grain size, grain morphology, and grain boundary characteristics, and the Euclidean distance algorithm is used to calculate the similarity between the copper rod to be processed and the samples in the process library. For example, if the grain size of a copper rod is 45μm (corresponding to the 30-50μm range in the process library) and the silver segregation degree at the grain boundary is 15% (the segregation degree of similar samples in the library is ≤20%), then process parameters with similar segregation degrees within this range will be prioritized for matching; For feature combinations that are not fully covered, such as new special-section copper rods, the rule reasoning engine is activated: if the grains are coarse (>80μm) and the grain boundary cleanliness is high, the system automatically recommends "heating temperature = recrystallization temperature + 80℃, holding time = conventional value × 1.5" to promote grain breakage through overheating; if grain boundary silver segregation >25% is detected, the cooling rate is forced to drop to below 5℃ / s to delay silver phase precipitation.

[0031] Furthermore, after matching and positioning, an initial process plan containing three core parameters is generated: Heating temperature: Based on the recrystallization temperature model and combined with grain size correction, for example, the heating temperature is increased by 20°C for every 10μm coarsening of the initial grains to ensure sufficient grain refinement. For example, the initial grain size of a copper rod is 50μm, and the calculated recrystallization temperature is approximately 450°C. After correction, the heating temperature is set to 620°C, with a reserve of 170°C for superheat. Holding time: Calculate the cross-section temperature difference equilibrium time based on the Fourier heat conduction equation and combine it with the grain boundary migration kinetics formula to ensure uniform distribution of alloy elements; Cooling rate: Based on the critical relationship between silver content and cooling rate, for example, when the silver content is 0.08%, the critical cooling rate is 7°C / s. Use stepped cooling, with a high temperature section of 10°C / s and a low temperature section of 5°C / s to avoid brittle phase precipitation; The generated initial parameters are synchronized to the heat treatment equipment through a visual interface, and the rationality of the parameters is automatically verified before starting the heating program, such as the temperature does not exceed the melting point of copper 1083°C and the cooling rate matches the equipment capacity.

[0032] In this embodiment, through the matching mechanism of "data-driven + knowledge fusion", the heat treatment process is transformed from "experience-dependent" to "precise mapping"; compared with traditional general process parameters, the fit between the initial parameters and the individual characteristics of the copper rod is improved, and the performance fluctuations caused by parameter mismatch are reduced from the source; the "trial and error" debugging of traditional processes is avoided, the single-batch process planning time is reduced, and production efficiency is improved; reasonable initial conditions are laid for subsequent real-time dynamic adjustments, forming a closed-loop control of "detection-matching-processing-feedback".

[0033] As a preferred embodiment of the above solution, during the heat treatment of oxygen-free silver-containing copper rods, the actual heat treatment results may deviate from expectations due to various factors, such as unstable equipment operating conditions and subtle differences in the raw material microstructure and composition. Therefore, multi-dimensional sensors and detection technologies are needed to capture key parameters reflecting the copper rod's microstructural evolution and process status in real time, providing real-time data support for subsequent deviation analysis and parameter adjustments.

[0034] Specifically, the heat treatment characteristic parameter set includes temperature field characteristic parameters, microstructure dynamic parameters, physical property parameters and process control parameters; the temperature field characteristic parameters include at least one of temperature gradient distribution and temperature change rate; the microstructure dynamic parameters include at least one of grain size, grain boundary migration rate and silver element distribution characteristics; the physical property parameters include at least one of residual stress field, conductivity dynamic value and hardness distribution characteristics; the process control parameters include at least one of oxygen content in the insulation stage, equipment power, quenching medium flow rate and quenching medium temperature.

[0035] More specifically, the temperature gradient distribution is collected by embedding K-type thermocouples in the axial direction (head, middle, and tail) of the copper rod in the heat treatment furnace to form an array of 6-8 temperature measurement points to ensure that the temperature distribution along the length of the copper rod is covered. The temperature of each point is recorded in real time at a frequency of 10Hz using a data acquisition card to calculate the axial temperature gradient. Temperature change rate acquisition: During the heating and cooling stages, the real-time temperature change rate is calculated based on the temperature difference between adjacent moments. Specifically, the temperature change per unit time is calculated at 10-second intervals. Grain size and grain boundary migration data are collected using a micro-metallographic microscope in the furnace combined with a high-speed camera to capture real-time images of the copper rod surface grains at 500x magnification. An image recognition algorithm is used to measure the equivalent diameter of the grains, outputting the average grain size every 5 minutes. Simultaneously, feature point tracking is performed on the continuous image sequence, calculating the ratio of grain boundary migration distance to time, and obtaining the grain boundary migration rate, which intuitively reflects the dynamics of grain growth. To collect the distribution characteristics of the silver element, the copper rod surface is scanned by X-ray fluorescence spectrometry to detect the real-time concentration distribution of the silver element, focusing on the segregation at the grain boundaries. Combined with the electron backscatter diffraction technology of the scanning electron microscope, the copper rod is scanned regularly to analyze the enrichment degree of the silver element in different grain boundary types, providing data support for judging the uniformity of the alloy element distribution. Residual stress field acquisition: using an X-ray stress meter, residual stress detection is performed on the copper rod surface in the axial, radial, and circumferential directions; the stress value is calculated using the Bragg equation; Conductivity dynamic value acquisition, using the four-probe method to measure conductivity online. By applying a constant current at both ends of the copper rod, measuring the voltage drop of the middle probe, and calculating the real-time conductivity; Hardness distribution characteristics were collected by scanning the copper rod surface at 2 mm intervals using an electromagnetic induction hardness tester to measure the Vickers hardness and draw a distribution curve. During the holding stage, oxygen content is collected by installing an infrared oxygen sensor in the heat treatment furnace to monitor the oxygen content in the furnace in real time; Equipment power and energy consumption collection: current and voltage sensors are installed at the heating power supply end to collect the power of the heating equipment in real time and calculate the unit energy consumption based on the mass of the copper rod; The quenching medium parameters are collected, the quenching medium flow rate is monitored by an electromagnetic flowmeter, and the quenching medium temperature is measured using a platinum resistance thermometer.

[0036] By collecting the above-mentioned heat treatment characteristic parameter set in real time, the actual state of the oxygen-free silver-containing copper rod during the heat treatment process can be comprehensively and dynamically understood. On the one hand, it can be used to compare with the preset target characteristic indicators. If a deviation is found, step S4 is triggered in time to perform deviation calculation and subsequent parameter adjustment. On the other hand, the long-term accumulation of data helps to further optimize the heat treatment process library, improve the accuracy and reliability of process matching, and provide a more complete reference basis for the heat treatment of more batches of oxygen-free silver-containing copper rods in the future.

[0037] In some embodiments of the present invention, based on the expected performance of the oxygen-free, silver-containing copper rod, clear and specific target characteristic indicators are set for various heat treatment characteristic parameters, including temperature field characteristic parameters, microstructural dynamic parameters, physical property parameters, and process control parameters. Simultaneously, a preset time for determining deviations is determined. This preset time is not set arbitrarily, but is determined by comprehensively considering the time characteristics of each stage in the heat treatment process and the general patterns of microstructural changes, ensuring that potential deviations can be detected promptly at critical time points.

[0038] Specifically, the preset time is a dynamic response time window, which satisfies the following calculation formula: ; Among them, t preset represents the preset time; d represents the real-time grain size; K0 represents the grain growth rate constant, which is a material intrinsic parameter that characterizes the grain boundary migration rate of the Ag-Cu system; Q represents the grain boundary migration activation energy, which reflects the inhibitory effect of silver atoms on the recrystallization process of the copper matrix; R represents the gas constant, which is a universal constant in thermodynamic calculations; T represents the real-time temperature of the copper rod surface in the heat treatment furnace; α represents the thermal hysteresis compensation factor, which is used to correct the deviation effect of temperature field fluctuation on grain growth prediction; ΔD represents the absolute difference between the current grain size and the target value; D target Indicates the target grain size, which is the ideal grain diameter set according to product performance requirements.

[0039] The formula introduces the real-time grain size d, real-time temperature T, and the absolute difference ΔD between the current grain size and the target value. It can adjust the preset time in real time according to the actual state of grain growth, temperature changes, and the gap with the target during the heat treatment process, rather than using a fixed value. This makes the preset time more in line with the actual process progress and improves the flexibility and accuracy of time setting. Through material intrinsic parameters such as the grain growth rate constant K0 and the grain boundary migration activation energy Q, the grain boundary migration rate of the Ag-Cu system and the hindering effect of silver atoms on the recrystallization of the copper matrix are fully considered, so that the calculation of the preset time conforms to the principles of material science and more accurately reflects the inherent laws of grain growth in this system. The thermal hysteresis compensation factor α can correct the deviation of the temperature field fluctuation on the grain growth prediction, ensuring that the preset time can still be reasonably adjusted when the temperature is unstable, reducing the time setting error caused by temperature interference and enhancing the robustness of the calculation model.

[0040] Furthermore, the preset target characteristic index refers to the ideal value or target range set for the heat treatment characteristic parameter set during the heat treatment process; the preset target characteristic index is determined based on the microstructural characteristics of the copper rod, the characteristic parameters of the copper rod and the final performance requirements, and specifically includes: Target range of temperature gradient distribution; target value of temperature change rate, such as the target heating rate in the heating stage and the target cooling rate in the cooling stage; target range of grain size, such as refinement to the target grain size; target value of grain boundary migration rate, such as the speed at which grain boundaries migrate to the target position; target value of silver element distribution characteristics, such as the uniform distribution of silver elements at the grain boundaries; target value of residual stress field, such as residual stress close to zero; target range of conductivity dynamic value, such as reaching high conductivity standards; target value of hardness distribution characteristics, such as uniform hardness distribution and compliance with design requirements; target range of oxygen content in the holding stage, such as below a certain threshold to avoid oxidation; target value of equipment power, such as ensuring stable heating power; target values of quenching medium flow rate and temperature, such as ensuring uniform cooling rate and compliance with process requirements.

[0041] If a heat treatment characteristic parameter fails to reach the preset target characteristic index, it is marked as a non-standard parameter; for each non-standard parameter, the deviation value between it and the target value is calculated; the deviation value can be positive (the actual value is higher than the target value) or negative (the actual value is lower than the target value); the deviation values of all non-standard characteristics are organized into an n-dimensional vector in a preset order to form a heat treatment deviation vector. The deviation vector is a quantitative description of the deviation from the expected situation during the heat treatment process; if a characteristic deviation exceeds the allowable range by 2 times, it is regarded as a serious abnormality, marked as an extreme value in the vector, and the emergency control mechanism is triggered.

[0042] In this embodiment, complex process anomalies are converted into computable mathematical vectors through quantitative deviation and structured expression, which is beneficial to subsequent precise control; the heat treatment deviation vector covers four dimensions of temperature, structure, performance, and equipment, avoiding the one-sidedness of single parameter monitoring. For example, by combining grain size deviation and conductivity deviation, it can be accurately determined whether the performance degradation is caused by grain coarsening or silver segregation; the deviation weight can also be adjusted according to the characteristics of the copper rod to ensure the targetedness of the control strategy; the deviation vector is used as an intermediate variable to connect the logical chain of real-time monitoring and parameter adjustment in series, so that the control algorithm can be iteratively optimized based on historical deviation data, and the process robustness can be gradually improved; the core link of the "perception-analysis-decision-making" closed loop of the heat treatment process is realized, and the scientificity and effectiveness of subsequent control actions are ensured through precise deviation quantification, and ultimately the stable improvement of the heat treatment quality of oxygen-free silver-containing copper rods is achieved.

[0043] In some embodiments of the present invention, based on the heat treatment deviation vector generated in step S4, the initial heat treatment process parameter set is dynamically controlled to generate an optimal heat treatment process parameter set, and the oxygen-free silver-containing copper rod is heat treated based on the optimal heat treatment process parameter set, specifically including: The heat treatment deviation vector is analyzed. Based on the sign of each process parameter in the heat treatment deviation vector, it is determined whether the parameter exceeds the target value (positive value) or fails to reach the target value (negative value). For example, a positive temperature change rate deviation indicates that the actual heating rate is too fast; a negative grain boundary migration rate deviation indicates that the grain boundary migration speed is too slow. Weights are assigned to different deviation values based on the degree of influence of the process parameters on the copper rod performance. For example, grain size has a greater impact on the strength and toughness of the copper rod, so its deviation weight is higher; oxygen content during the holding stage has a greater impact on conductivity, so its deviation weight is also higher. According to the analysis results of the deviation vector, the initial heat treatment process parameter set is adjusted to make the process parameters closer to the target characteristic indicators; the control strategy needs to comprehensively consider the size, weight and severity of the deviation value to ensure that the adjusted process parameters can effectively improve the non-standard characteristics.

[0044] Specifically, for heating temperature control, adjustments are made based on the deviations of the temperature field, microstructure, and other related factors in the deviation vector. If the temperature change rate during the heating stage is lower than the target value, such as the temperature change rate term in the deviation vector is negative, the grain size grows slowly, and the grain size deviation is negative, the heating temperature is appropriately increased to increase the superheat and promote grain refinement and grain boundary migration. For example, if the initial heating temperature is 600°C, if the temperature change rate deviation is -1.5°C / s and the grain size does not reach the target, the temperature can be adjusted to 620°C. If the temperature gradient distribution is abnormal, such as the radial temperature gradient in a certain area is greater than the target value, the heating power is adjusted through zone temperature control to balance the temperature field, rather than directly changing the overall heating temperature. The holding time is dynamically adjusted based on deviations such as grain size and grain boundary migration rate. If the grain size does not reach the target during the holding stage, such as the deviation vector shows a grain size deviation of -5μm and the grain boundary migration rate is lower than expected, the holding time is extended, such as by 10%-20% of the original time. For example, if the initial holding time is 60 minutes, it can be extended to 66-72 minutes to ensure sufficient grain homogenization. If the silver element distribution characteristics do not meet the standards, such as the deviation of silver segregation at the grain boundaries of +8%, the heating temperature can be lowered by 5-10°C while extending the holding time to slow down the silver element segregation trend and promote its uniform diffusion. For cooling rate control, optimization is carried out based on deviations such as silver element distribution and residual stress. If the silver element segregation degree exceeds the standard, such as the silver element distribution characteristic item in the deviation vector is abnormal, the cooling rate is reduced to delay the formation of Ag2Cu precipitation phase and improve the conductivity. If the residual stress field deviation is large, such as the residual stress is higher than the target value of 20MPa, a step-by-step cooling adjustment is adopted: the high-temperature section maintains the original speed for rapid cooling, and the low-temperature section reduces the cooling rate to release the internal stress.

[0045] The adjusted parameters must be checked for rationality, including physical constraint verification and process compatibility verification; the heating temperature must be lower than the melting point of copper, and a safety threshold must be reserved; the cooling rate must be within the equipment capacity; check whether the adjusted parameter combination conforms to the logic of the heat treatment stage; for example, after the heating temperature is increased, the holding time needs to be adjusted accordingly to ensure sufficient heat conduction; after the cooling rate changes, the quenching medium flow rate, temperature and other control parameters need to be matched synchronously; after the verification is passed, the optimal heat treatment process parameter set will be transmitted to the heat treatment equipment for execution, and the copper rod status will be monitored in real time to ensure that the heat treatment process is accurate and controllable.

[0046] In this embodiment, dynamic optimization of the heat treatment process is achieved through the logical chain of "deviation vector-parameter control-verification implementation": differentiated control strategies are formulated for different deviations to avoid traditional "one-size-fits-all" adjustments. For example, the cooling rate is adjusted separately to solve the silver segregation problem without affecting the grain refinement effect in the heating stage; the mutual influence of heating temperature, holding time, and cooling rate is comprehensively considered, such as shortening the holding time after increasing the temperature, or extending the holding time when reducing the cooling rate, to ensure the overall coordination of the process; parameter conflicts are eliminated through the verification mechanism, such as excessively high temperature and cooling speed not supported by the equipment, so that the regulated parameters meet both quality requirements and engineering feasibility.

[0047] In some schemes, multiple embodiments of the present application can be combined and the combined scheme can be implemented. Optionally, some operations in the process of each method embodiment are optionally combined, and / or the order of some operations is optionally changed. In addition, the execution order between the steps of each process is only exemplary and does not constitute a limitation on the execution order between the steps. There can also be other execution orders between the steps. It is not intended to indicate that the execution order is the only order in which these operations can be performed. Ordinary technicians in this field will think of many ways to reorder the operations described herein. In addition, it should be noted that the process details involved in a certain embodiment of this article are also applicable to other embodiments in a similar manner, or different embodiments can be used in combination.

[0048] Furthermore, some steps in the method embodiments may be equivalently replaced with other possible steps. Alternatively, some steps in the method embodiments may be optional and may be deleted in certain usage scenarios. Alternatively, other possible steps may be added to the method embodiments. Furthermore, the various method embodiments may be implemented separately or in combination.

[0049] like Figure 2 As shown, the present invention also provides a system for optimizing process parameters of heat treatment of oxygen-free silver-containing copper rods, which specifically includes the following modules: A parameter acquisition module is used to obtain the microstructural characteristics and copper rod characteristic parameters of the oxygen-free silver-containing copper rod to be heat-treated; wherein the microstructural characteristics at least include grain size, grain morphology and grain boundary characteristics; the copper rod characteristic parameters at least include specification characteristics and composition characteristics; A parameter matching and positioning module is used to use the microstructural features and copper rod characteristic parameters as positioning conditions, match and locate in a pre-built heat treatment process library, and determine the initial heat treatment process parameter set; the initial heat treatment process parameter set at least includes heating temperature, holding time and cooling rate, and this parameter set is used for the heat treatment of oxygen-free silver-containing copper rods; A real-time acquisition module is used to collect the heat treatment characteristic parameter set of the oxygen-free silver-containing copper rod in real time during the heat treatment process; a deviation calculation module, configured to determine whether at least one heat treatment characteristic in the heat treatment characteristic parameter set fails to meet a preset target characteristic index within a preset time period; if so, calculate the deviation values of all the heat treatment characteristics that fail to meet the target index and convert them into a heat treatment deviation vector; The parameter control module is used to control the initial heat treatment process parameter set determined by the parameter matching and positioning module based on the heat treatment deviation vector obtained by the deviation calculation module, obtain the optimal heat treatment process parameter set, and use the optimal parameter set to heat treat the oxygen-free silver-containing copper rod.

[0050] In this embodiment, the parameter acquisition module and the parameter matching and positioning module cooperate with each other, and can accurately match the initial heat treatment process parameter set from the process library according to the unique microstructural characteristics and characteristic parameters of each oxygen-free silver-containing copper rod; changing the previous extensive method of relying on experience or general standards can effectively solve the problem that the unified process parameters cannot achieve the best effect due to individual differences in copper rods, improve the adaptability of the process to different copper rods, and ensure that each copper rod can obtain a relatively suitable initial heat treatment plan; the real-time acquisition module and the deviation calculation module work together to monitor the heat treatment characteristic parameters of the copper rod in real time during the heat treatment process; once it is found that the parameters deviate from the preset target, the deviation calculation module quickly calculates Deviations are converted into vectors, so that the parameter control module can adjust the initial process parameters in time according to the deviation vector to obtain the optimal parameter set; the entire process can dynamically correct parameter deviations caused by factors such as equipment status and raw material differences, effectively ensuring the stability of the final copper rod performance, reducing performance fluctuations caused by process deviations, and improving product quality consistency; the system has a real-time monitoring and adjustment mechanism, and when faced with a complex and changing production environment, it can flexibly respond to changes in equipment operating status and subtle differences in the microstructure and composition of raw materials; by dynamically adjusting parameters, the heat treatment process is always kept in the optimal state, enhancing the flexibility of the process and its adaptability to different production scenarios.

[0051] This embodiment divides the functional modules according to the above-described method example. For example, each functional module can be divided according to its function, or two or more functions can be integrated into a single processing module. The integrated modules can be implemented in hardware. It should be noted that the module division in this embodiment is illustrative and represents only one logical functional division. In actual implementation, other division methods may be used.

[0052] The basic principles, main features, and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the foregoing embodiments. The foregoing embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and modifications are intended to fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for optimizing heat treatment process parameters of oxygen-free silver-containing copper rod, characterized in that: include: Obtaining the microstructural characteristics and characteristic parameters of the oxygen-free silver-containing copper rod to be heat-treated; Using the microstructural features and the copper rod characteristic parameters as positioning conditions, matching and positioning are performed in a pre-built heat treatment process library to determine an initial heat treatment process parameter set, and heat treating the oxygen-free silver-containing copper rod based on the initial heat treatment process parameter set; During the heat treatment process, the heat treatment characteristic parameter set of the oxygen-free silver-containing copper rod is collected in real time; In response to at least one heat treatment feature in the heat treatment feature parameter set failing to reach a preset target feature index within a preset time, calculating deviation values of all heat treatment features that fail to reach the target index and converting them into a heat treatment deviation vector; Based on the heat treatment deviation vector, the initial heat treatment process parameter set is regulated to obtain an optimal heat treatment process parameter set, and the oxygen-free silver-containing copper rod is heat treated accordingly.

2. The method for optimizing heat treatment process parameters of oxygen-free silver-containing copper rod according to claim 1, characterized in that: The microstructural characteristics include at least grain size, grain morphology and grain boundary characteristics; The copper rod characteristic parameters include at least specification characteristics and composition characteristics.

3. The method for optimizing heat treatment process parameters of oxygen-free silver-containing copper rod according to claim 2, characterized in that: The preset time is the dynamic response time window, which satisfies the following calculation formula: ； Among them, t preset represents the preset time; d represents the real-time grain size; K0 represents the grain growth rate constant, which is a material intrinsic parameter that characterizes the grain boundary migration rate of the Ag-Cu system; Q represents the grain boundary migration activation energy, which reflects the inhibitory effect of silver atoms on the recrystallization process of the copper matrix; R represents the gas constant, which is a universal constant in thermodynamic calculations; T represents the real-time temperature of the copper rod surface in the heat treatment furnace; α represents the thermal hysteresis compensation factor, which is used to correct the deviation effect of temperature field fluctuation on grain growth prediction; ΔD represents the absolute difference between the current grain size and the target value; D target Indicates the target grain size, which is the ideal grain diameter set according to product performance requirements.

4. The method for optimizing heat treatment process parameters of oxygen-free silver-containing copper rod according to claim 2, characterized in that: The initial heat treatment process parameter set includes at least heating temperature, holding time and cooling rate.

5. The method for optimizing heat treatment process parameters of oxygen-free silver-containing copper rod according to claim 1, characterized in that: The heat treatment characteristic parameter set includes temperature field characteristic parameters, microstructure dynamic parameters, physical property parameters and process control parameters.

6. The method for optimizing heat treatment process parameters of oxygen-free silver-containing copper rod according to claim 5, characterized in that: The temperature field characteristic parameter includes at least one of the temperature gradient distribution and the temperature change rate; The microstructure dynamic parameter includes at least one of grain size, grain boundary migration rate and silver element distribution characteristics; The physical performance parameter includes at least one of residual stress field, dynamic value of electrical conductivity and hardness distribution characteristics; The process control parameters include at least one of the oxygen content in the holding stage, equipment power, quenching medium flow rate, and quenching medium temperature.

7. The method for optimizing heat treatment process parameters of oxygen-free silver-containing copper rod according to claim 2, characterized in that: The heat treatment process library is used to store initial heat treatment process parameter sets under different combinations of microstructure characteristics and copper rod characteristic parameters; The heat treatment process library retrieves an initial heat treatment process parameter set that matches the input copper rod characteristic parameters based on a preset indexing method.

8. The method for optimizing heat treatment process parameters of oxygen-free silver-containing copper rod according to claim 7, characterized in that: The preset indexing method in the heat treatment process library includes: According to the specification characteristics of the copper rod to be processed, an initial heat treatment process parameter set that matches the specification characteristics is selected and marked as a first-order initial heat treatment process parameter set; Setting matching weights for grain size, grain morphology, and grain boundary characteristics, respectively, and calculating the similarity between the copper rod to be processed and all the first-order initial heat treatment process parameter sets; The first-order initial heat treatment process parameter set with the highest similarity is used as the initial heat treatment process parameter set for the copper rod to be processed.

9. The method for optimizing heat treatment process parameters of oxygen-free silver-containing copper rod according to claim 5, characterized in that: The method for collecting temperature gradient distribution in the temperature field characteristic parameters includes: A preset number of temperature sensors are arranged in the axial direction of the copper rod in the heat treatment furnace; Based on the preset frequency, collect the monitoring temperature of each temperature sensor; Based on the collected monitoring temperature, the axial temperature gradient of the copper rod is calculated.

10. A heat treatment process parameter optimization system for oxygen-free silver-containing copper rods, characterized in that: include: A parameter acquisition module is used to obtain the microstructure characteristics and characteristic parameters of the oxygen-free silver-containing copper rod to be heat-treated; The parameter matching and positioning module is used to use the microstructure characteristics and copper rod characteristic parameters as positioning conditions, match and locate in the pre-built heat treatment process library, and determine the initial heat treatment process parameter set; A real-time acquisition module is used to collect the heat treatment characteristic parameter set of the oxygen-free silver-containing copper rod in real time during the heat treatment process; a deviation calculation module, configured to respond to a determination, within a preset time period, whether at least one heat treatment characteristic in the heat treatment characteristic parameter set fails to reach a preset target characteristic index; If there are any non-compliant cases, calculate the deviation values of all non-compliant heat treatment features and convert them into heat treatment deviation vectors; The parameter control module is used to control the initial heat treatment process parameter set based on the heat treatment deviation vector obtained by the deviation calculation module to obtain the optimal heat treatment process parameter set, and use it to heat treat the oxygen-free silver-containing copper rod.

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