Aluminum alloy extrusion temperature control method based on numerical calculation

Abstract

The application discloses an aluminum alloy extrusion temperature control method based on numerical calculation and relates to the technical field of metal material processing, which comprises the following steps: constructing a thermal-mechanical coupling model of an aluminum alloy extrusion process; obtaining initial extrusion process parameters through numerical simulation and target optimization based on the thermal-mechanical coupling model; performing aluminum alloy extrusion based on the initial extrusion process parameters and calculating the extrusion outlet section average temperature and the section deviation temperature when the aluminum alloy extrusion outlet section average temperature reaches stability; judging whether the extrusion outlet section average temperature is in a preset temperature range and whether the section deviation temperature is not greater than a preset deviation threshold; and determining the optimal extrusion speed according to the judgment result and performing aluminum alloy extrusion by using the optimal extrusion speed. The application can realize the uniformity and consistency control of the aluminum alloy extrusion outlet section temperature, improve the aluminum alloy extrusion forming efficiency and forming quality, and reduce the raw material loss of the aluminum alloy extrusion forming.

Description

Technical Field

[0001] This invention relates to the field of metal material processing technology, and in particular to a method for controlling the extrusion temperature of aluminum alloys based on numerical calculation. Background Technology

[0002] Aluminum alloy profiles are widely used in aerospace, transportation, building structures, and industrial equipment due to their advantages such as lightweight, high strength, corrosion resistance, ease of processing and forming, and good electrical conductivity. Extrusion forming is one of the most important processing methods for aluminum alloy profiles. Especially for products with complex cross-sectional shapes, high dimensional accuracy requirements, or special performance needs, extrusion is often an indispensable or even the only processing method in their forming process.

[0003] In the aluminum alloy profile extrusion process, the temperature distribution and stability at the extrusion exit are key factors affecting the final microstructure, dimensional accuracy, surface quality, and forming efficiency of the product. Excessive exit temperature can lead to coarse grains, severe surface oxidation, and even hot cracking; conversely, excessively low temperatures may increase the extrusion load, reduce material flowability, and result in insufficient filling or internal defects. More importantly, the uniformity of temperature distribution across the extrusion cross-section directly affects the deformation coordination of different parts of the profile and the distribution of residual stress after cooling, thus decisively influencing the product's flatness, uniformity of mechanical properties, and long-term dimensional stability.

[0004] Currently, the main methods for controlling the extrusion exit temperature of aluminum alloy profiles include empirical control, speed closed-loop control, die temperature control, and billet gradient heating. Empirical control involves operators manually adjusting the extrusion speed based on their experience and the displayed aluminum alloy profile exit temperature. This method suffers from significant debugging lag, low temperature control accuracy, and reliance on operator experience and skill. Speed ​​closed-loop control uses a temperature sensor installed at the exit to monitor the temperature in real time and feeds it back to the control system to adjust the extrusion speed, thus achieving effective control of the exit temperature. This method requires simple equipment and is easy to implement, but its temperature control accuracy is low due to significant lag in temperature regulation. Die temperature control regulates the exit temperature by heating and cooling the extrusion cylinder or die in sections. This method requires sophisticated equipment, has a complex system, consumes a lot of energy, and often results in unsatisfactory temperature control due to complex die structures and variable thermal boundary conditions, especially limiting its ability to regulate local temperatures for complex cross-section profiles. Billet gradient heating controls the extrusion exit temperature by gradually heating the billet according to the extrusion conditions. This method can theoretically improve the uniformity of outlet temperature, but the process design is complex, the equipment requirements are high, and it is difficult to flexibly adapt to the production switching of different specifications or alloy grades.

[0005] In recent years, numerical simulation techniques such as the finite element method (FEM) have been introduced into extrusion process research to predict the distribution of physical quantities such as temperature and stress fields. However, most existing numerical simulation techniques are used in offline process analysis and preliminary parameter screening stages, failing to be deeply integrated with online production processes. Meanwhile, existing temperature control methods mainly focus on the average temperature of the extrusion exit section, without fully considering and effectively controlling the temperature uniformity within the section, leading to problems such as uneven local profile performance and residual stress concentration. Furthermore, the temperature instability zone present in the initial stage of extrusion can cause the extruded material to become waste due to substandard temperature, resulting in raw material loss.

[0006] Therefore, it is necessary to provide a method for controlling the extrusion temperature of aluminum alloys to overcome the technical problems existing in the above-mentioned existing extrusion temperature control methods. Summary of the Invention

[0007] To address some or all of the technical problems existing in the prior art, this invention provides a numerical calculation-based method for controlling the temperature of aluminum alloy extrusion. This method can achieve uniform and consistent temperature control at the aluminum alloy extrusion exit section, improve the efficiency and quality of aluminum alloy extrusion forming, and reduce raw material loss in aluminum alloy extrusion forming.

[0008] The technical solution of the present invention is as follows:

[0009] A numerical calculation-based method for controlling the extrusion temperature of aluminum alloys is provided, including:

[0010] Construct a thermo-mechanical coupling model of the aluminum alloy extrusion process;

[0011] Based on the aforementioned thermo-mechanical coupling model, a first relationship between the initial extrusion process parameters, extrusion time, and average temperature of the extrusion exit section is determined through numerical simulation fitting. Based on the thermo-mechanical coupling model and the first relationship, a second relationship between the initial extrusion process parameters and the extrusion time required for the average temperature of the extrusion exit section to stabilize is determined through numerical simulation fitting. A third relationship between the initial extrusion process parameters and the average temperature of the extrusion exit section when the average temperature of the extrusion exit section stabilizes is also determined. Finally, a fourth relationship between the average temperature of the extrusion exit section when the average temperature of the extrusion exit section stabilizes and the section deviation temperature is determined. Based on the second, third, and fourth relationships, with minimizing aluminum alloy loss as the optimization objective and with the constraints that the average temperature of the extrusion exit section when the average temperature of the extrusion exit section stabilizes is within a preset temperature range and the section deviation temperature when the average temperature of the extrusion exit section stabilizes is not greater than a preset deviation threshold, the initial extrusion process parameters are obtained through objective optimization. The initial extrusion process parameters include: initial temperature of the aluminum alloy billet, initial temperature of the extrusion barrel, initial temperature of the extrusion die, and initial extrusion speed.

[0012] Aluminum alloy extrusion was performed based on initial extrusion process parameters, and the average temperature and deviation temperature of the extrusion exit section when the average temperature of the aluminum alloy extrusion exit section reached a stable value were calculated.

[0013] Determine whether the average temperature of the extrusion outlet section is within the preset temperature range, and whether the temperature deviation of the section is not greater than the preset deviation threshold.

[0014] Based on the judgment results, the optimal extrusion speed is determined, and the aluminum alloy is extruded using the optimal extrusion speed.

[0015] Furthermore, in some embodiments, the amount of aluminum alloy loss is determined in the following manner:

[0016] ;

[0017] in, This indicates the amount of aluminum alloy loss. Indicates the density of aluminum alloy, Indicates the initial extrusion speed. This indicates the cross-sectional area of ​​the extrusion cylinder. This indicates the extrusion time required for the average temperature at the extrusion exit section to reach a stable level.

[0018] Furthermore, in some implementations, when obtaining the initial extrusion process parameters through objective optimization, the objective function is:

[0019] ;

[0020] in, This indicates the initial temperature of the aluminum alloy billet. Indicates the initial temperature of the extrusion cylinder. Indicates the initial temperature of the extrusion die. This represents the average temperature at the extrusion exit section when the average temperature of the extrusion exit section reaches a stable value. This indicates the minimum temperature within the preset temperature range. This indicates the maximum temperature within the preset temperature range. This represents the section deviation temperature at which the average temperature of the extrusion exit section reaches a stable level. This indicates the preset deviation threshold. The second equation represents the relationship between the initial extrusion process parameters and the extrusion time required for the average temperature at the extrusion exit section to reach a stable level. This is the third equation representing the relationship between the initial extrusion process parameters and the average temperature of the extrusion exit section when the average temperature reaches a stable level. This is the fourth equation representing the relationship between the average temperature of the extrusion exit section and the section deviation temperature when the average temperature of the extrusion exit section reaches a stable level.

[0021] Furthermore, in some embodiments, the average temperature of the extrusion outlet section and the deviation temperature of the section are calculated and determined using temperature data from multiple preset temperature measuring points on the extrusion outlet section.

[0022] Furthermore, in some embodiments, the average temperature of the extrusion outlet section is determined by the following method:

[0023] ;

[0024] The cross-sectional deviation temperature is determined in the following way:

[0025] ;

[0026] in, This indicates the average temperature at the extrusion exit section. Indicates the number of temperature measurement points. Indicates the first Temperature values ​​at each temperature measurement point This indicates the temperature deviation of the cross section.

[0027] Furthermore, in some embodiments, determining the optimal extrusion speed based on the judgment result includes:

[0028] If the judgment result is that the average temperature of the extrusion outlet section is within the preset temperature range and the temperature deviation of the section is not greater than the preset deviation threshold, then the current extrusion speed is determined as the optimal extrusion speed.

[0029] If the judgment result is that the average temperature of the extrusion outlet section is not within the preset temperature range or the temperature deviation of the section is greater than the preset deviation threshold, then the current extrusion speed is corrected according to the preset correction rule, and the extrusion and judgment are re-performed based on the corrected extrusion speed, iterating until the optimal extrusion speed is determined.

[0030] Furthermore, in some embodiments, the preset correction rule is:

[0031] ;

[0032] in, This indicates the corrected extrusion speed. Indicates the current extrusion speed. Indicates the speed adjustment amount. This indicates the speed adjustment ratio coefficient. This represents the average temperature at the extrusion exit section when the average temperature of the extrusion exit section reaches a stable value. This represents the boundary temperature of the extrusion exit section when the average temperature of the extrusion exit section reaches a stable level. This represents the coefficient indicating the influence of extrusion speed on the average temperature of the extrusion exit section. This indicates the minimum temperature within the preset temperature range. This indicates the maximum temperature within the preset temperature range. This represents the section deviation temperature at which the average temperature of the extrusion exit section reaches a stable level. This indicates the preset deviation threshold. This represents the coefficient that indicates the influence of extrusion speed on the cross-sectional deviation temperature.

[0033] Furthermore, in some embodiments, the method further includes:

[0034] When extruding aluminum alloys at the optimal extrusion speed, the average temperature of the extrusion outlet section and the section deviation temperature are calculated in real time when the average temperature of the aluminum alloy extrusion outlet section reaches a stable value. It is then determined whether the average temperature of the extrusion outlet section is within the preset temperature range and whether the section deviation temperature is not greater than the preset deviation threshold. Based on the determination results, the optimal extrusion speed is re-determined, and the aluminum alloy extrusion and determination are continued at the optimal extrusion speed until the aluminum alloy extrusion is completed.

[0035] Furthermore, in some embodiments, the method further includes:

[0036] If the extrusion speed is not corrected during multiple consecutive aluminum alloy extrusion processes, the current extrusion speed is taken as the final optimal extrusion speed, and the aluminum alloy extrusion is carried out at the final optimal extrusion speed until the aluminum alloy extrusion is completed.

[0037] The main advantages of the technical solution of this invention are as follows:

[0038] The numerical calculation-based aluminum alloy extrusion temperature control method of this invention, through the construction of a thermo-mechanical coupling model for numerical simulation and target optimization, can accurately predict and obtain the optimal initial extrusion process parameters, greatly reducing the development cycle and cost of aluminum alloy extrusion process parameters. At the same time, considering the average temperature and deviation temperature of the extrusion exit section, combined with a speed correction mechanism of real-time monitoring and closed-loop feedback, the optimal extrusion speed can be determined, thereby effectively controlling the stability and uniformity of the temperature of the extrusion exit section, ensuring that the temperature continuously meets the process requirements, significantly improving the extrusion forming efficiency and quality of aluminum alloy profiles, reducing material loss in the temperature unstable stage, greatly improving extrusion production efficiency and material utilization, and is applicable to the stable batch production of complex cross-section profiles. Attached Figure Description

[0039] The accompanying drawings, which are included to provide a further understanding of embodiments of the invention and constitute a part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute an undue limitation of the invention. In the drawings:

[0040] Figure 1A flowchart illustrating a numerical calculation-based method for controlling the extrusion temperature of aluminum alloys, provided as an embodiment of the present invention;

[0041] Figure 2 The graph shows the average temperature-time of the aluminum alloy extrusion exit section before and after speed correction, as provided in an embodiment of the present invention. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0043] The technical solutions provided by the embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0044] refer to Figure 1 This invention provides a method for controlling the extrusion temperature of aluminum alloys based on numerical calculation. The method includes the following steps:

[0045] Step 1: Construct a thermo-mechanical coupling model of the aluminum alloy extrusion process;

[0046] Step 2: Based on the thermo-mechanical coupling model, the first relationship between the initial extrusion process parameters, extrusion time, and average temperature of the extrusion exit section is determined through numerical simulation fitting. Based on the thermo-mechanical coupling model and the first relationship, the second relationship between the initial extrusion process parameters and the extrusion time required for the average temperature of the extrusion exit section to reach stability is determined through numerical simulation fitting. The third relationship between the initial extrusion process parameters and the average temperature of the extrusion exit section when the average temperature of the extrusion exit section reaches stability is also determined. Finally, the fourth relationship between the average temperature of the extrusion exit section when the average temperature of the extrusion exit section reaches stability and the section deviation temperature is determined. Based on the second, third, and fourth relationships, the initial extrusion process parameters are obtained through target optimization with the goal of minimizing aluminum alloy loss and the constraints that the average temperature of the extrusion exit section when the average temperature of the extrusion exit section reaches stability is within a preset temperature range and the section deviation temperature when the average temperature of the extrusion exit section reaches stability is not greater than a preset deviation threshold.

[0047] Step 3: Perform aluminum alloy extrusion based on the initial extrusion process parameters, and calculate the average temperature of the extrusion exit section and the section deviation temperature when the average temperature of the aluminum alloy extrusion exit section reaches a stable level.

[0048] Step 4: Determine whether the average temperature of the extrusion outlet section is within the preset temperature range, and whether the temperature deviation of the section is not greater than the preset deviation threshold.

[0049] Step 5: Based on the judgment result, determine the optimal extrusion speed and use the optimal extrusion speed to extrude the aluminum alloy.

[0050] In this embodiment of the invention, the initial extrusion process parameters include: initial temperature of aluminum alloy billet, initial temperature of extrusion cylinder, initial temperature of extrusion die, and initial extrusion speed.

[0051] In this embodiment of the invention, if the rate of temperature rise of the average temperature of the extrusion outlet section is not greater than a preset rate threshold, it indicates that the average temperature of the extrusion outlet section has reached stability. The rate of temperature rise of the average temperature of the extrusion outlet section can be obtained by taking the derivative of the first relationship with respect to time; the preset rate threshold corresponding to the rate of temperature rise is specifically set according to actual needs, for example, the preset rate threshold is set to 0.1℃ / s.

[0052] In this embodiment of the invention, based on the thermo-mechanical coupling model, multiple sets of initial extrusion process parameters and multiple sets of extrusion times are set for numerical simulation. The average temperature of the extrusion outlet section of each set of initial extrusion process parameters at multiple different extrusion times is obtained. By fitting the multiple sets of data obtained, the first relationship between the initial extrusion process parameters, extrusion time and the average temperature of the extrusion outlet section is obtained.

[0053] In this embodiment of the invention, based on the thermo-mechanical coupling model and the first relational expression, multiple sets of initial extrusion process parameters are set for numerical simulation. The extrusion time required for the average temperature of the extrusion outlet section to stabilize, the average temperature of the extrusion outlet section when the average temperature of the extrusion outlet section stabilizes, and the section deviation temperature when the average temperature of the extrusion outlet section stabilizes are obtained for each set of initial extrusion process parameters. By fitting the obtained multiple sets of initial extrusion process parameters and the corresponding extrusion time data required for the average temperature of the extrusion outlet section to stabilize, a second relational expression between the initial extrusion process parameters and the extrusion time required for the average temperature of the extrusion outlet section to stabilize is obtained. By fitting the obtained multiple sets of initial extrusion process parameters and the corresponding average temperature data of the extrusion outlet section when the average temperature of the extrusion outlet section stabilizes, a third relational expression between the initial extrusion process parameters and the average temperature of the extrusion outlet section when the average temperature of the extrusion outlet section stabilizes is obtained. By fitting the obtained multiple sets of average temperature and section deviation temperature data of the extrusion outlet section when the average temperature of the extrusion outlet section stabilizes, a fourth relational expression between the average temperature and section deviation temperature of the extrusion outlet section when the average temperature of the extrusion outlet section stabilizes is obtained.

[0054] In this embodiment of the invention, when obtaining the initial extrusion process parameters through target optimization, the second, third, and fourth relations are used as one of the constraints.

[0055] It should be noted that when obtaining the initial extrusion process parameters through objective optimization, the constraints can be expanded and supplemented according to actual needs. For example, the constraints can also include the range of values ​​for the initial extrusion process parameters.

[0056] In this embodiment of the invention, by obtaining the initial extrusion process parameters in the above manner, a set of comprehensive optimal initial extrusion process parameters can be determined scientifically and efficiently. This enables the average temperature and deviation temperature of the extrusion exit section to be quickly controlled within the preset requirements, and significantly reduces material waste caused by temperature instability. It can also reduce the development cycle and cost of aluminum alloy extrusion process parameters, and provide a high-precision process starting point for subsequent real-time control, thereby improving the quality and economic benefits of extrusion forming from the source.

[0057] The aluminum alloy extrusion temperature control method based on numerical calculation provided in this invention constructs a thermo-mechanical coupling model for numerical simulation and target optimization. This method can accurately predict and obtain the optimal initial extrusion process parameters, greatly reducing the development cycle and cost of aluminum alloy extrusion process parameters. At the same time, considering the average temperature and deviation temperature of the extrusion exit section, and combining a speed correction mechanism with real-time monitoring and closed-loop feedback, the optimal extrusion speed can be determined. This effectively controls the stability and uniformity of the temperature at the extrusion exit section, ensuring that the temperature continuously meets the process requirements. This significantly improves the extrusion forming efficiency and quality of aluminum alloy profiles, reduces material loss during the temperature instability stage, greatly improves extrusion production efficiency and material utilization, and is applicable to the stable batch production of complex cross-section profiles.

[0058] Furthermore, in one embodiment of the present invention, a thermo-mechanical coupling model of the aluminum alloy extrusion process is constructed using finite element analysis software.

[0059] Specifically, when constructing a thermo-mechanical coupling model of the aluminum alloy extrusion process using finite element analysis software, a geometric model including the aluminum alloy billet, extrusion cylinder, and extrusion die is first established and meshed. Then, the material constitutive model and thermophysical properties of the aluminum alloy are defined, and the extrusion speed, friction conditions, and initial temperature field boundary conditions are set. Finally, the coupling analysis module is selected in the solver, and based on the aforementioned settings, a thermo-mechanical coupling model of the aluminum alloy extrusion process is constructed. The thermo-mechanical coupling model is a finite element model.

[0060] Furthermore, in this embodiment of the invention, the aluminum alloy loss is determined in the following manner:

[0061] ;

[0062] in, This indicates the amount of aluminum alloy loss. Indicates the density of aluminum alloy, Indicates the initial extrusion speed. This indicates the cross-sectional area of ​​the extrusion cylinder. This indicates the extrusion time required for the average temperature at the extrusion exit section to reach a stable level.

[0063] Based on the above settings, in step 203, when obtaining the initial extrusion process parameters through target optimization, the optimization objective function is expressed as:

[0064] ;

[0065] in, This indicates the initial temperature of the aluminum alloy billet. Indicates the initial temperature of the extrusion cylinder. Indicates the initial temperature of the extrusion die. Indicates the initial extrusion speed. This represents the average temperature at the extrusion exit section when the average temperature of the extrusion exit section reaches a stable value. This indicates the minimum temperature within the preset temperature range. This indicates the maximum temperature within the preset temperature range. This represents the section deviation temperature at which the average temperature of the extrusion exit section reaches a stable level. This indicates the preset deviation threshold. The second equation represents the relationship between the initial extrusion process parameters and the extrusion time required for the average temperature at the extrusion exit section to reach a stable level. This is the third equation representing the relationship between the initial extrusion process parameters and the average temperature of the extrusion exit section when the average temperature reaches a stable level. This is the fourth equation representing the relationship between the average temperature of the extrusion exit section and the section deviation temperature when the average temperature of the extrusion exit section reaches a stable level.

[0066] In obtaining the initial extrusion process parameters through target optimization, conventional target optimization algorithms can be used, which will not be elaborated here.

[0067] Furthermore, in one embodiment of the present invention, the average temperature and the deviation temperature of the extrusion outlet section are calculated and determined using temperature data from multiple preset temperature measuring points on the extrusion outlet section.

[0068] Specifically, the average temperature of the extrusion exit section is determined in the following way:

[0069] ;

[0070] The cross-sectional deviation temperature is determined in the following way:

[0071] ;

[0072] in, This indicates the average temperature at the extrusion exit section. Indicates the number of temperature measurement points. Indicates the first Temperature values ​​at each temperature measurement point This indicates the temperature deviation of the cross section.

[0073] In this embodiment of the invention, the temperature data of multiple preset temperature measuring points on the extrusion outlet section are obtained by measuring the temperature data using temperature sensors arranged at the extrusion outlet.

[0074] Furthermore, in one embodiment of the present invention, determining the optimal extrusion speed based on the judgment result includes the following steps:

[0075] If the judgment result is that the average temperature of the extrusion outlet section is within the preset temperature range and the temperature deviation of the section is not greater than the preset deviation threshold, then the current extrusion speed is determined as the optimal extrusion speed.

[0076] If the judgment result is that the average temperature of the extrusion outlet section is not within the preset temperature range or the temperature deviation of the section is greater than the preset deviation threshold, then the current extrusion speed is corrected according to the preset correction rule, and the extrusion and judgment are re-performed based on the corrected extrusion speed, iterating until the optimal extrusion speed is determined.

[0077] In this embodiment of the invention, a closed-loop control of extrusion speed with real-time judgment and dynamic correction is constructed in the above manner, so that the extrusion speed can be adaptively adjusted according to the online monitoring results of the average temperature and the deviation temperature of the extrusion outlet section, thereby significantly improving the temperature control accuracy and response speed, and ensuring the stability and quality consistency of the extrusion process.

[0078] Furthermore, in this embodiment of the invention, the preset correction rule is expressed as:

[0079] ;

[0080] in, This indicates the corrected extrusion speed. Indicates the current extrusion speed. Indicates the speed adjustment amount. This indicates the speed adjustment ratio coefficient. This represents the average temperature at the extrusion exit section when the average temperature of the extrusion exit section reaches a stable value. This represents the boundary temperature of the extrusion exit section when the average temperature of the extrusion exit section reaches a stable level. This represents the coefficient indicating the influence of extrusion speed on the average temperature of the extrusion exit section. This indicates the minimum temperature within the preset temperature range. This indicates the maximum temperature within the preset temperature range. This represents the section deviation temperature at which the average temperature of the extrusion exit section reaches a stable level. This indicates the preset deviation threshold. This represents the coefficient that indicates the influence of extrusion speed on the cross-sectional deviation temperature.

[0081] Among them, parameters and The specific settings should be determined based on the actual situation. For example, they can be obtained by fitting actual extrusion data of aluminum alloys, or they can be specified manually.

[0082] In this embodiment of the invention, by correcting the extrusion speed using the preset correction rules set above, the optimal extrusion speed can be quickly determined, further improving temperature control accuracy and response speed.

[0083] refer to Figure 2 , Figure 2 The graph shows the average temperature-time at the aluminum alloy extrusion exit section before and after speed correction, as provided in an embodiment of the invention. It can be seen that the optimal extrusion speed can be determined with only two speed corrections.

[0084] Furthermore, in one embodiment of the present invention, the method further includes the following steps:

[0085] Step 6: When extruding aluminum alloy at the optimal extrusion speed, calculate the average temperature of the extrusion outlet section and the section deviation temperature in real time when the average temperature of the aluminum alloy extrusion outlet section reaches a stable value. Determine whether the average temperature of the extrusion outlet section is within the preset temperature range and whether the section deviation temperature is not greater than the preset deviation threshold. Based on the judgment results, redetermine the optimal extrusion speed and continue to extrude aluminum alloy and make judgments at the optimal extrusion speed until the aluminum alloy extrusion is completed.

[0086] In this embodiment of the invention, by continuously implementing real-time monitoring, judgment and dynamic speed adjustment throughout the extrusion process, adaptive closed-loop control is achieved throughout the entire extrusion production process. It can proactively respond to various dynamic disturbances in the extrusion production process, ensuring that the temperature of the extrusion outlet section can be stably maintained within the preset temperature range and uniformly distributed at every stage from the start to the end of extrusion. This significantly improves the stability and product consistency of long-term, large-volume production, and minimizes scrap caused by process drift.

[0087] Furthermore, in one embodiment of the present invention, step 6 further includes:

[0088] If the extrusion speed is not corrected during multiple consecutive aluminum alloy extrusion processes, the current extrusion speed is taken as the final optimal extrusion speed, and the aluminum alloy extrusion is carried out at the final optimal extrusion speed until the aluminum alloy extrusion is completed.

[0089] Among them, multiple consecutive aluminum alloy extrusion processes, such as three consecutive aluminum alloy extrusion processes.

[0090] In this embodiment of the invention, the optimal extrusion speed verified in the previous iterations is locked and applied to subsequent mass production through the above processing. This can ensure the absolute stability and efficiency of process parameters in large-scale production, reduce the load of real-time calculation, avoid excessive waste of computing resources, and optimize production energy efficiency while improving product quality consistency.

[0091] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Additionally, the terms "front," "back," "left," "right," "upper," and "lower" in this document refer to the placement shown in the accompanying drawings.

[0092] 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 them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A numerical calculation-based aluminum alloy extrusion temperature control method characterized by, The method comprises the following steps: constructing a thermal-mechanical coupling model of an aluminum alloy extrusion process; determining a first relationship between initial extrusion process parameters, extrusion time and average temperature of an extrusion outlet section based on the thermal-mechanical coupling model through numerical simulation fitting, determining a second relationship between the initial extrusion process parameters and the extrusion time required for the average temperature of the extrusion outlet section to reach stability based on the thermal-mechanical coupling model and the first relationship, determining a third relationship between the initial extrusion process parameters and the average temperature of the extrusion outlet section when the average temperature of the extrusion outlet section reaches stability, and determining a fourth relationship between the average temperature of the extrusion outlet section when the average temperature of the extrusion outlet section reaches stability and the cross-section deviation temperature based on the second relationship, the third relationship and the fourth relationship, obtaining the initial extrusion process parameters through objective optimization with the minimum aluminum alloy loss as the optimization objective, the average temperature of the extrusion outlet section when the average temperature of the extrusion outlet section reaches stability within a preset temperature range, and the cross-section deviation temperature when the average temperature of the extrusion outlet section reaches stability not greater than a preset deviation threshold as the constraint conditions, wherein the initial extrusion process parameters comprise an initial temperature of an aluminum alloy blank, an initial temperature of an extrusion cylinder, an initial temperature of an extrusion die and an initial extrusion speed; extruding the aluminum alloy based on the initial extrusion process parameters and calculating the average temperature of the extrusion outlet section and the cross-section deviation temperature when the average temperature of the extrusion outlet section reaches stability; determining whether the average temperature of the extrusion outlet section is within a preset temperature range and whether the cross-section deviation temperature is not greater than a preset deviation threshold; determining the optimal extrusion speed according to the determination result and extruding the aluminum alloy with the optimal extrusion speed.

2. The numerical calculation-based aluminum alloy extrusion temperature control method according to claim 1, characterized by, The aluminum alloy loss is determined by the following method: ； wherein, represents the aluminum alloy loss amount, represents the aluminum alloy density, represents the initial extrusion speed, represents the cross-sectional area of the extrusion cylinder, represents the extrusion time required for the average temperature of the extrusion outlet cross-section to reach a steady state.

3. The numerical calculation-based aluminum alloy extrusion temperature control method according to claim 2, characterized by, When the initial extrusion process parameters are obtained through objective optimization, the optimization objective function is: ； wherein, represents the initial temperature of the aluminum alloy billet, represents the initial temperature of the extrusion barrel, represents the initial temperature of the extrusion die, represents the average temperature of the extrusion exit cross-section at the time when the average temperature of the extrusion exit cross-section reaches a steady state, represents a minimum temperature of a preset temperature range, represents a maximum temperature of a preset temperature range, represents a cross-sectional deviation temperature at the time when the average temperature of the extrusion exit cross-section reaches a steady state, represents a preset deviation threshold value, represents a second relationship between the initial extrusion process parameters and the extrusion time required for the average temperature of the extrusion exit cross-section to reach a steady state, represents a third relationship between the initial extrusion process parameters and the average temperature of the extrusion exit cross-section at the time when the average temperature of the extrusion exit cross-section reaches a steady state, represents a fourth relationship between the average temperature of the extrusion exit cross-section and the cross-sectional deviation temperature at the time when the average temperature of the extrusion exit cross-section reaches a steady state.

4. The numerical calculation-based aluminum alloy extrusion temperature control method according to claim 1, characterized by, The average temperature of the extrusion outlet section and the cross-section deviation temperature are calculated and determined by using the temperature data of a plurality of preset temperature measuring points on the extrusion outlet section.

5. The numerical calculation-based aluminum alloy extrusion temperature control method according to claim 4, characterized by, The average temperature of the extrusion outlet section is determined by the following method: ； The cross-section deviation temperature is determined by the following method: ； wherein, represents the average temperature of the extrusion outlet cross section, represents the number of temperature measurement points, represents the temperature value of the th temperature measurement point, represents the cross section deviation temperature.

6. The numerical calculation-based aluminum alloy extrusion temperature control method according to claim 1, characterized by, The determination of the optimal extrusion speed according to the determination result comprises: If the determination result is that the average temperature of the extrusion outlet section is within the preset temperature range and the cross-section deviation temperature is not greater than the preset deviation threshold, the current extrusion speed is determined as the optimal extrusion speed; If the determination result is that the average temperature of the extrusion outlet section is not within the preset temperature range or the cross-section deviation temperature is greater than the preset deviation threshold, the current extrusion speed is corrected according to a preset correction rule, and the extrusion and determination are performed again based on the corrected extrusion speed, and the iteration is performed until the optimal extrusion speed is determined.

7. The numerical calculation-based aluminum alloy extrusion temperature control method according to claim 6, characterized by, The preset correction rule is: ； wherein, represents a corrected extrusion speed, represents a current extrusion speed, represents a speed adjustment amount, represents a speed adjustment proportionality coefficient, represents an extrusion outlet cross-sectional average temperature at which the extrusion outlet cross-sectional average temperature reaches a steady state, represents an extrusion outlet cross-sectional boundary temperature at which the extrusion outlet cross-sectional average temperature reaches a steady state, represents an extrusion speed influence coefficient on the extrusion outlet cross-sectional average temperature, represents a temperature minimum value of a preset temperature range, represents a temperature maximum value of a preset temperature range, represents a cross-sectional deviation temperature at which the extrusion outlet cross-sectional average temperature reaches a steady state, represents a preset deviation threshold value, represents an extrusion speed influence coefficient on the cross-sectional deviation temperature.

8. The numerical calculation-based aluminum alloy extrusion temperature control method according to claim 1, characterized by, The method further comprises: In the aluminum alloy extrusion at the optimal extrusion speed, the average temperature of the extrusion outlet section and the section deviation temperature when the average temperature of the aluminum alloy extrusion outlet section reaches stability are calculated in real time, whether the average temperature of the extrusion outlet section is in a preset temperature range and whether the section deviation temperature is not greater than a preset deviation threshold are judged, the optimal extrusion speed is determined again according to the judgment result, the aluminum alloy extrusion is continuously carried out at the optimal extrusion speed, and the judgment is continuously carried out until the aluminum alloy extrusion is completed.

9. The numerical calculation-based aluminum alloy extrusion temperature control method according to claim 8, characterized by, The method further comprises: If the extrusion speed is not corrected in the continuous multiple aluminum alloy extrusion processes, the current extrusion speed is taken as a final optimal extrusion speed, the aluminum alloy extrusion is carried out at the final optimal extrusion speed until the aluminum alloy extrusion is completed.

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