Online quenching device and quenching method for metal profiles

Abstract

This invention discloses an online quenching device and method for metal profiles. The method includes: obtaining the quenching inflection point temperature T0 of the metal profile; slowly cooling the metal profile by air cooling and / or mist cooling, so that the temperature distribution of the cross-sectional temperature field at the point where the slow cooling is completed is between T0 and T0+50℃; and water quenching the slowly cooled metal profile to room temperature. The online quenching device and method for metal profiles provided by this invention, by rationally dividing the cooling stages according to the quenching inflection point temperature and switching different cooling modes, and by optimizing the combination of gradual cooling and multiple cooling methods, achieves dynamic control of the cooling rate and uniform management of the temperature field. This ensures that the profile can maximize its mechanical properties while maintaining good dimensional stability, significantly improving yield and production efficiency.

Description

[0001] The present application claims priority to the Chinese patent application No. CN2025103187874, filed on March 18, 2025, entitled "Metal profile online quenching device and quenching method", the entire content of which is incorporated herein by reference. TECHNICAL FIELD

[0002] The present application belongs to the technical field of metal material processing, and specifically relates to a metal profile online quenching method and a device for quenching metal profiles online based on the quenching method. BACKGROUND

[0003] In order to achieve excellent mechanical properties and stable shape and size, extruded aluminum profiles usually need to be subjected to online quenching and artificial aging treatment. The online quenching rapidly cools the aluminum profile through a cooling medium, so that the internal organization of the aluminum profile changes, thereby significantly improving the strength and hardness of the aluminum profile. At the same time, the alloying elements in the aluminum alloy remain in the supersaturated solid solution after quenching, which prepares for subsequent aging precipitation, further improving the mechanical properties of the aluminum profile. However, if the selection of the quenching medium (such as wind, water, mist, etc.) and the regulation of the quenching intensity are not reasonable, the cooling speed of each part of the profile will be inconsistent, causing residual stress in the profile, which in turn causes deformation, resulting in a decrease in the mechanical properties and shape and size precision of the profile, and in severe cases, even causing the profile to become a waste or defective product, reducing the product's pass rate. Therefore, it is crucial to reasonably select the quenching medium and regulate the quenching process to ensure the quality of the extruded profile.

[0004] Currently, the commonly used online quenching methods include air cooling, water cooling, and mist cooling. Air cooling and mist cooling usually do not cause large stress in the profile, thereby reducing the deformation amount of the profile and maintaining the product size precision. However, their cooling speed is relatively slow, which cannot meet the quenching requirements of some alloys that require high cooling speed. When mist cooling, the mist will instantly vaporize upon contact with the high-temperature profile, forming a water vapor layer that hinders direct contact between the mist and the profile surface, resulting in unstable cooling effect. Water cooling can rapidly cool the profile due to its high thermal conductivity and heat capacity, thereby forming a supersaturated solid solution in the profile and improving the mechanical properties of the material. However, the cooling speed of water cooling is too fast, which may cause large thermal stress in the aluminum alloy during quenching, especially for profiles with uneven wall thickness distribution and complex cross-sectional shape, resulting in increased deformation of the profile, and in severe cases, even causing quenching cracks, ultimately leading to a decrease in the product's pass rate.

[0005] Existing patent CN113976653A discloses a production process for extruding multi-cavity aluminum alloy profiles. Although this patent also employs a combination of air and water cooling, its approach remains at a general guidance level, lacking specific technical solutions for applying this concept to online quenching. Based solely on the empirical characteristics of 7005 alloy, the patent does not provide clear and specific technical solutions or implementation methods for achieving precise temperature control, ensuring cooling uniformity, and dynamically adjusting the temperature field at different stages during the online quenching process.

[0006] Therefore, it is necessary to provide a new solution to the above-mentioned technical problems. Summary of the Invention

[0007] The purpose of this invention is to provide an online quenching device and quenching method for metal profiles, which can avoid or reduce the problem of quenching deformation while ensuring the mechanical properties of metal profiles.

[0008] To achieve the above objectives, the technical solution provided by the present invention is as follows: In a first aspect, the present invention provides an online quenching method for metal profiles, comprising the following steps: Obtain the quenching inflection point temperature T0 of the metal profile; slowly cool the metal profile by air cooling and / or mist cooling so that the temperature distribution of the cross-sectional temperature field at the location where the slow cooling is completed is between T0 and T0+50℃; quench the slowly cooled metal profile by water cooling to cool it to room temperature.

[0009] In one or more embodiments, obtaining the quenching (mechanical property) inflection point temperature T0 of the metal profile includes the following steps: Multiple samples of the same grade as the metal profile were subjected to solution treatment; the solution-treated samples were then gradient-cooled to different target temperatures and then water-quenched to room temperature; the water-quenched samples were subjected to peak aging treatment, and then the mechanical properties of each sample were tested. The quenching inflection point temperature T0 of the metal profile was obtained based on the mechanical properties of each sample.

[0010] In one or more embodiments, obtaining the quenching inflection point temperature T0 of the metal profile based on the mechanical properties of the sample includes the following steps: The mechanical property loss rate L at each target temperature is calculated using the following formula. i : ; In the formula, P i P represents the mechanical property value of each sample. max P represents the highest mechanical property value among all samples. min This represents the lowest mechanical property value among all samples. Plot the mechanical performance loss rate L i With target temperature T i The relationship curve will not exceed the set threshold L for performance loss rate. th Maximum mechanical property loss rate L i The corresponding temperature point is determined as the quenching inflection point temperature T0, where the performance loss rate is set to a threshold L. th The value range is 5% to 20%.

[0011] In one or more embodiments, the target temperature gradients of the plurality of air-cooled samples are arranged, and the temperature difference between two adjacent target temperatures is 5°C to 60°C.

[0012] In one or more embodiments, the metal profile is slowly cooled by air cooling and / or mist cooling, so that the temperature distribution of the cross-sectional temperature field at the location where the slow cooling is completed is between T0 and T0+50℃, including the following steps: The air cooling and / or mist cooling process of the metal profile is simulated using simulation software to determine the quenching parameters of the metal profile; the metal profile is then slowly cooled according to the quenching parameters so that the temperature distribution of the cross-sectional temperature field at the location where the slow cooling is completed is between T0 and T0+50℃.

[0013] The quenching parameters include the reference cooling rate of the slow cooling zone, the position of the nozzle, the flow rate of the nozzle, the spray angle, and the spray height.

[0014] In one or more embodiments, the online quenching method for metal profiles includes a slow cooling real-time control step: Monitor the average temperature T of the profile section at the point where the slow cooling of the metal profile is completed. avg When the average temperature of the profile section T avg Deviation from the center value of the target interval T target At T0 + 25℃, based on the quenching parameters determined by the above simulation, adjust the cooling rate during slow cooling according to the following formula: Among them, V ref V is the reference cooling rate corresponding to the quenching parameters obtained from the simulation; adj The adjusted target cooling rate; μ is the response coefficient, ranging from 0.2 to 0.5.

[0015] In one or more embodiments, the air-cooling and / or mist-cooling process of the metal profile is simulated using simulation software to determine the quenching parameters of the metal profile, including the following steps: Simulation software is used to simulate the air cooling and / or mist cooling process of metal profiles to determine the cross-sectional temperature distribution when the lowest cross-sectional temperature at the point where the slow cooling is completed reaches the quenching inflection point temperature T0. It is then determined whether the cross-sectional temperature distribution is within the range of T0 to T0+50℃. If the cross-sectional temperature distribution does not meet the range of T0 to T0+50℃, the quenching parameters are adjusted according to the simulation results. The simulation is then repeated based on the adjusted quenching parameters until the cross-sectional temperature distribution at the point where the slow cooling is completed is within the range of T0 to T0+50℃.

[0016] In one or more embodiments, the step of water quenching the slowly cooled metal profile to room temperature via water cooling specifically includes the following steps: Online water quenching simulation was performed on the metal profiles that had undergone slow cooling using simulation software. By adjusting the water quenching parameters, the temperature difference between the cross sections of the metal profiles was kept between 5°C and 10°C, and the metal profiles that had undergone slow cooling were cooled to room temperature within 10 seconds.

[0017] In one or more embodiments, the online quenching method for metal profiles includes a real-time water cooling control step: Controlling the cooling rate V of the slowest cooling region on the cross-section of the metal profile q satisfy: Among them, V crit The minimum critical cooling rate required to cool a slowly cooled metal profile to room temperature; T entry This represents the region with the slowest cooling rate on the cross-section of the metal profile during water cooling; λ is an adjustment coefficient, ranging from 0.1 to 0.3; T room Room temperature.

[0018] Secondly, the present invention provides a quenching apparatus for the aforementioned online quenching method for metal profiles, comprising: a slow cooling zone and a fast cooling zone arranged sequentially along the extrusion direction of the metal profile; the slow cooling zone is used to perform air cooling and / or mist cooling on the extruded metal profile, so that the temperature distribution of the cross-sectional temperature field at the position where the slow cooling is completed is between T0 and T0+50℃; the fast cooling zone is used to perform water cooling on the metal profile after air cooling and / or mist cooling.

[0019] In one or more embodiments, the slow cooling zone and the fast cooling zone form a cooling channel through which the metal profile can pass, and the cooling channel is surrounded by nozzles for spraying cooling medium, the angle and flow rate of the nozzles being adjustable.

[0020] In one or more embodiments, the quenching device includes a bottom support and a top support, with downwardly extending mounting plates on the left and right sides of the top support, and nozzles facing the cooling channel are provided on the top of the bottom support, the bottom of the top support, and the mounting plates.

[0021] In one or more embodiments, the bottom support is provided with a support seat for supporting the metal profile, the bottom support is connected to the lifting mechanism and can be lifted and lowered under the drive of the lifting mechanism, and the support seat is provided with rollers for supporting the metal profile to be fed along the extrusion direction.

[0022] In one or more embodiments, the quenching apparatus includes a real-time temperature monitoring module for monitoring the temperature of the metal profile. The real-time temperature monitoring module, such as a thermocouple array or an infrared temperature sensor, can be used to dynamically monitor the temperature field distribution of the cross-section and obtain the average temperature T of the profile cross-section. avg And to identify the region T on the cross-section where cooling is slowest during water cooling of metal profiles. entry Through these sensors, the system can acquire temperature data and cooling rates at different locations on the profile and feed them back to the control module. This allows the system to adjust the parameters of the air-cooling equipment and the cooling rate as needed, ensuring a uniform temperature distribution within the target range.

[0023] In one or more embodiments, a control module is included, which is connected to a nozzle and a real-time temperature monitoring module. The control module is used to acquire the temperature of the metal profile and adjust the nozzle based on the temperature monitoring results, such as adjusting parameters like the nozzle position, nozzle flow rate, spray angle, and spray height.

[0024] Compared with the prior art, the online quenching device and quenching method for metal profiles provided by the present invention achieves dynamic control of the cooling rate and uniform management of the temperature field by rationally dividing the cooling stage and switching different cooling modes through the quenching inflection point temperature, and by optimizing the combination of gradual cooling and multiple cooling methods. This enables the profiles to ensure mechanical properties to the greatest extent and have good dimensional stability, which can significantly improve the yield and production efficiency. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1This is a flowchart of an online quenching method for metal profiles according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the quenching device in one embodiment of the present invention; Figure 3a This is a front view of the quenching device in one embodiment of the present invention; Figure 3b This is a schematic diagram of the cooling channel and nozzle layout of the quenching device in one embodiment of the present invention; Figure 4 This is a schematic diagram of the cross-sectional shape of the aluminum alloy profile in Embodiment 1 of the present invention; Figure 5 This is a schematic diagram of the cross-sectional shape of the aluminum alloy profile in Embodiment 2 of the present invention; Figure 6 The images show the Vickers hardness test results of aluminum alloy profiles at different water quenching temperatures in Examples 1 and 2 of this invention.

[0027] Explanation of key reference numerals: 31-bottom bracket, 32-top bracket, 33-mounting plate, 34-nozzle, 35-cooling channel, 36-support base, 37-lifting mechanism, 38-roller. Detailed Implementation

[0028] To enable those skilled in the art to better understand the technical solutions of this invention, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this invention.

[0029] The online quenching method for metal profiles of this invention is proposed to solve the problems of uneven cooling rate and severe quenching deformation in existing aluminum alloy profile quenching processes. In modern industrial production, aluminum alloy profiles, as a lightweight and high-strength structural material, are widely used in aerospace, transportation, construction and other fields. However, in order to improve the mechanical properties of the profiles, quenching is an essential process, but existing online quenching methods have many limitations.

[0030] Specifically, existing online quenching methods such as air cooling, mist cooling, spraying, and water immersion each have their own shortcomings. Air cooling and mist cooling have low cooling rates, making it difficult to meet the quenching strength requirements of aluminum alloy profiles, resulting in insufficient utilization of mechanical properties. While water immersion and spraying quenching can rapidly cool the profiles, the excessively rapid cooling rate creates large temperature gradients, especially at different points in the profile cross-section due to variations in wall thickness and cross-sectional dimensions, leading to severe uneven cooling rates. For these reasons, significant internal stresses are generated within the profile, causing deformation, twisting, and even microcracks, severely affecting the dimensional accuracy and performance of the profile. Because the cooling process involves the interaction of multiple complex factors, existing technologies struggle to achieve precise control of the cooling rate, thus failing to effectively suppress deformation.

[0031] To address the aforementioned problems, this invention proposes an innovative online quenching method for metal profiles. The method can be summarized as follows: First, a novel method based on the quantification of mechanical property loss rate is used to obtain the precise quenching inflection point temperature T0. Specifically, multiple samples of the same grade are subjected to gradient air cooling, water quenching, and aging treatments, and their mechanical properties are tested. The mechanical property loss rate L at each temperature is then calculated. i And plot its relationship with the corresponding target temperature T. i The relationship curve will not exceed the set threshold L for performance loss rate. th Maximum mechanical property loss rate L (5%–20%) i The corresponding temperature point was determined as the quenching inflection point temperature T0, which provides a precise and objective critical temperature basis for the subsequent division of the cooling stage.

[0032] After obtaining the quenching inflection point temperature T0, the cooling stages are rationally divided and different cooling modes are switched based on the quenching inflection point temperature T0 to achieve gradual changes in the cooling rate and precise real-time control. Specifically, above the quenching inflection point temperature T0 of the metal profile's mechanical properties, slow cooling is performed using air cooling and / or mist cooling. During the slow cooling process, a real-time control mechanism is introduced: monitoring the average cross-sectional temperature T at the point where the slow cooling of the metal profile is completed. avg When the average temperature of the profile section T avg Deviation from the center value of the target interval T target =T0+25℃, according to the formula The cooling rate is dynamically adjusted. This feedback regulation ensures that the temperature field of the profile section is uniformly distributed within the ideal range of T0~T0+50℃ at the end of slow cooling, effectively reducing the temperature gradient and internal stress in the high-temperature zone and minimizing the risk of deformation.

[0033] When the temperature drops to near the mechanical performance inflection point temperature T0, the system switches to water cooling for rapid cooling. During the water cooling stage, active cooling rate control is also implemented: by controlling the cooling rate V of the slowest-cooling area on the profile cross-section. q To satisfy This control strategy ensures that even the slowest cooling areas achieve the necessary cooling intensity, thereby suppressing deformation by managing cooling uniformity while maintaining rapid cooling, quenching effect, and material mechanical properties.

[0034] The entire cooling process, through precise acquisition of T0 and real-time control of slow cooling and water cooling rates, achieves refined and dynamic management of temperature field distribution and cooling history. The combined application of these methods enables this invention to precisely balance the contradiction between quenching strength (ensuring mechanical properties) and dimensional accuracy (controlling deformation), solving the problem of precise cooling rate control in existing technologies. The online quenching method for metal profiles provided by this invention rationally divides the cooling stages by the quenching inflection point temperature and switches between different cooling modes. It also optimizes the combination of gradual cooling and multiple cooling methods, particularly by introducing the aforementioned quantitative T0 determination method and phased real-time cooling rate control strategy. This achieves dynamic and precise control of the cooling rate and uniform management of the temperature field, ensuring that the profiles maximize mechanical properties while maintaining good dimensional stability. This significantly improves yield and production efficiency, and has broad industrial application prospects.

[0035] Please refer to Figure 1 The diagram shown is a flowchart of an online quenching method for metal profiles according to an embodiment of the present invention. The online quenching method for metal profiles specifically includes the following steps: S101: Obtain the quenching inflection point temperature T0 of the metal profile.

[0036] It should be noted that the mechanical property (quenching) inflection point temperature T0 represents the critical point at which the mechanical properties of a metal profile undergo significant changes during cooling. When the temperature of the metal profile is significantly higher than T0, its strength and hardness are usually lower, and the material is more prone to plastic deformation. Therefore, in the temperature range above T0, a slower cooling method should be adopted to reduce the risk of deformation. When the temperature drops to near or below T0, the cooling rate should be accelerated to ensure the mechanical properties of the alloy and achieve a stronger quenching effect.

[0037] In one exemplary embodiment, obtaining the quenching inflection point temperature T0 of the metal profile specifically includes the following steps: performing solution treatment on multiple samples of the same grade as the metal profile; gradually cooling the multiple samples after solution treatment to different target temperatures by air cooling, and then water quenching them to room temperature; performing peak aging treatment on the multiple samples after water quenching, and then testing the mechanical properties of each sample, and obtaining the quenching inflection point temperature T0 of the metal profile based on the mechanical properties of the multiple samples.

[0038] More specifically, when obtaining the quenching inflection point temperature T0 of a metal profile based on the mechanical properties of multiple samples, the target temperature T is first calculated according to the following formula. i mechanical property loss rate L i : ; In the formula, P i P represents the mechanical property value of each sample. max P represents the highest mechanical property value among all samples. min This represents the lowest mechanical property value among all samples. Redraw the mechanical performance loss rate L i With target temperature T i The relationship curve will not exceed the set threshold L for performance loss rate. th Maximum mechanical property loss rate L i The corresponding temperature point is determined as the quenching inflection point temperature T0, where the performance loss rate is set to a threshold L. th The value range is 5% to 20%.

[0039] Compared to traditional empirical methods, the method for determining T0 based on the quantified mechanical performance loss rate, through systematic gradient experiments and quantification formulas, makes the determination of the inflection point temperature more objective and repeatable, reducing the bias of human experience judgment; secondly, the performance loss rate threshold L is set... th Setting the threshold within a reasonable range of 5% to 20% achieves a scientific balance between ensuring core mechanical properties (with controllable loss) and avoiding the risk of deformation due to overcooling. This provides a reliable and quantitative temperature reference for precise control of subsequent slow cooling and water cooling stages, thereby improving the stability and controllability of the entire quenching process from the source. Performance loss rate threshold L th The setting is based on the requirements of the application field of metal profiles. For example, if applied to the aerospace field, the performance indicators are high, and the performance loss rate threshold L is high. th Set it low, for example, 5%.

[0040] The purpose of solution treatment is to fully dissolve the alloying elements in the metal to form a homogeneous solid solution structure, providing a good foundation for subsequent cooling and strengthening. The sample is typically heated to a predetermined high temperature (e.g., 540°C) and held at that temperature for a period of time to ensure that the internal structure of the material reaches a stable state.

[0041] After solution treatment, the samples were removed from the heat treatment furnace and subjected to air cooling at different rates. Multiple samples were air-cooled to different target temperatures, such as 520℃, 480℃, 440℃, 400℃, 360℃, and 300℃. The selection of these target temperatures was based on material properties and experimental requirements, aiming to capture key points in the changes of mechanical properties during cooling. Air cooling, with its relatively gentle cooling rate, avoids drastic changes in internal stress in the high-temperature range, thereby reducing early plastic deformation. Afterward, each sample was rapidly transferred to water for quenching, quickly reducing the temperature to room temperature. The purpose of water quenching is to form a supersaturated solid solution, preparing for age hardening.

[0042] After cooling, the samples undergo aging treatment. Aging treatment involves holding the sample at a specific temperature for an extended period (e.g., 175°C for 8 hours) to allow alloying elements to precipitate in the solid solution, forming strengthening phases. After aging treatment, the samples are removed and subjected to mechanical property tests, such as Vickers hardness testing or other strength tests. These tests allow for the evaluation of the changes in hardness and strength of each sample at different air-cooled temperatures.

[0043] Analyzing these test data allows us to determine the inflection point temperature T0 of the mechanical properties. This typically represents a critical point where hardness or strength changes significantly with decreasing temperature. Above T0, the performance change is relatively small; below T0, the performance declines noticeably. This inflection point temperature T0 represents the temperature range that requires special attention during the cooling process and is a key factor in determining the cooling method and rate.

[0044] By determining the temperature range T0, an optimal cooling strategy can be developed for the quenching process of metal profiles. Above T0, slower air cooling and / or mist cooling are used to reduce internal stress and deformation. Approaching T0, rapid cooling (such as water cooling) is switched to ensure the material's strength and hardness. This effectively balances profile deformation and mechanical properties, reducing quenching deformation while ensuring the profile's mechanical properties meet application requirements.

[0045] In one exemplary embodiment, the sample has dimensions of Φ9.5×H10mm and is provided with a socket for inserting a thermocouple. The multiple samples are arranged in a target temperature gradient for air cooling, and the temperature difference between two adjacent target temperatures is 30~60℃.

[0046] The specimen dimensions are Φ9.5 × H10 mm, meaning the metal specimen used in the experiment has specific geometric specifications: a diameter of 9.5 mm and a height of 10 mm. Appropriate specimen dimensions ensure that the material's thermal conductivity and cooling characteristics represent the behavior of the actual profile during heat treatment. This also facilitates accurate temperature measurement via thermocouple insertion and allows for subsequent control of the cooling rate based on temperature monitoring results. The small size and regular shape of the specimen provide a controllable and stable cooling environment during the experiment, reducing errors introduced by excessively large sizes or complex shapes. Furthermore, this dimensional setting ensures accurate temperature measurement after thermocouple insertion, as the relatively uniform temperature field inside the specimen helps in accurately monitoring the material's thermal changes at different temperature stages.

[0047] During solution treatment and air-cooling experiments, multiple samples were arranged to be air-cooled to different target temperatures to form an ordered temperature gradient. This arrangement of target temperature gradients means that the temperature points to which the samples were cooled are distributed according to a predetermined pattern, with the temperature difference between two adjacent target temperatures controlled within the range of 30–60°C. Specifically, a temperature difference of 30–60°C can clearly capture the influence of different cooling temperatures on the mechanical properties of the samples; at the same time, this temperature difference will not be too large, so as not to miss key temperature range information. Therefore, the purpose of using this gradient arrangement is to systematically observe and analyze how material properties change with temperature, thereby accurately determining the quenching inflection point temperature T0.

[0048] For example, multiple samples with dimensions of Φ9.5 × H10 mm are prepared, and a small hole is drilled at the center of the sample height for inserting a type K thermocouple. The thermocouple is used to monitor the sample temperature in real time during the heat treatment process. Next, these samples are placed in a heat treatment furnace for solution treatment, heated to a predetermined temperature (e.g., 540℃) and held for a certain time. Subsequently, the samples are removed from the furnace one by one and air-cooled in front of a fan to different target temperatures, such as 520℃, 480℃, 440℃, 400℃, 360℃, and 300℃, and then quickly placed in water to cool to room temperature. After water cooling, an aging treatment is performed at 175℃ for 8 hours to stabilize the microstructure of the samples.

[0049] Subsequently, Vickers hardness tests were performed on these aged samples, and the hardness variation patterns of each sample were analyzed. By comparing the mechanical property data at different air-cooled target temperatures, the inflection point temperature T0 can be determined. Below this temperature T0, water cooling significantly increases the degree of decrease in hardness and strength with temperature, while above this temperature T0, the changes in hardness and strength tend to decrease more gradually. Through the aforementioned experimental analysis, the specific value of T0 can be determined.

[0050] S102: The metal profile is slowly cooled by air cooling and / or mist cooling, so that the temperature distribution of the cross-sectional temperature field at the location where the metal profile has been slowly cooled is between T0 and T0+50℃.

[0051] It is understandable that T0 represents the quenching inflection point temperature of the material, that is, the critical point at which the material's strength and hardness rapidly increase. Controlling the temperature distribution of the cross-sectional temperature field at the point where the metal profile has just completed slow cooling (the point where it is ready for water quenching) within the range of T0 to T0+50℃ ensures that the profile will not undergo severe deformation in the high-temperature region due to excessively rapid cooling, and also lays a uniform temperature foundation for subsequent rapid cooling, ultimately ensuring the quenching effect and the mechanical properties of the profile.

[0052] For example, it can be adopted Figure 2 The quenching apparatus shown quenches metal profiles. As the metal profiles are extruded, they pass through a slow cooling zone and a fast cooling zone in sequence. In the slow cooling zone, the metal profiles are slowly cooled, so that the temperature distribution of the cross-sectional temperature field at the point where the slow cooling is completed (i.e., the point where the metal profiles have just entered the fast cooling zone after completing slow cooling) is between T0 and T0+50℃.

[0053] Air-cooled and / or mist-cooled equipment can be arranged along the extrusion direction of the metal profile, ensuring that the air-cooling and / or mist-cooling medium is evenly distributed around the metal profile. For precise temperature field control, the air-cooling equipment should have flow rate and direction adjustment capabilities. For example, adjustable nozzles can adjust the intensity and angle of air cooling according to the profile's cross-sectional shape, size, and material properties to achieve more efficient temperature control and cooling rate control. Furthermore, real-time temperature monitoring modules, such as thermocouple arrays or infrared temperature sensors, can be used to dynamically monitor the temperature field distribution across the cross-section, subsequently enabling the acquisition of the average cross-sectional temperature T0. avg And to identify the region T on the cross-section where cooling is slowest during water cooling of metal profiles. entry Through these sensors, the system can acquire temperature data and cooling rates at different locations on the profile and feed them back to the control module. This allows the system to adjust the parameters of the air-cooling equipment and the cooling rate as needed, ensuring a uniform temperature distribution within the target range.

[0054] In one exemplary embodiment, the metal profile is slowly cooled by air cooling and / or mist cooling, so that the temperature distribution of the cross-sectional temperature field at the location where the slow cooling is completed is between T0 and T0+50℃. Specifically, the following steps are included: simulating the air cooling and / or mist cooling process of the metal profile using simulation software to determine the quenching parameters for the metal profile; and air cooling the metal profile according to the quenching parameters, so that the temperature distribution of the cross-sectional temperature field at the location where the slow cooling is completed is between T0 and T0+50℃.

[0055] It should be noted that the air-cooling and / or mist-cooling behavior of metal profiles can be virtually simulated using heat treatment simulation software to optimize quenching parameters, such as airflow rate, flow rate, nozzle angle, and spray position. Through such simulation analysis, researchers can predict the temperature field distribution under different cooling conditions in advance, select the optimal cooling strategy, and avoid problems caused by uneven cooling rates.

[0056] Due to variations in the cross-sectional shape and wall thickness of metal profiles, a single air-cooling and / or mist-cooling strategy often fails to achieve a uniform temperature distribution. This can lead to rapid cooling of thin-walled sections and slower cooling of thick-walled sections, resulting in stress concentration and deformation. In such cases, using heat treatment simulation software (such as QForm or ANSYS) for air-cooling simulation can significantly improve the controllability of the cooling process. Through simulation, researchers can observe temperature changes in different regions and precisely adjust the position and spray angle of the air-cooling and / or mist-cooling nozzles to match the air-cooling and / or mist-cooling effect to the cross-sectional characteristics of the profile. For example, software simulations may show that thicker wall areas require higher air velocities or more concentrated airflow to accelerate cooling, while thinner wall areas require lower air velocities to avoid excessively rapid cooling.

[0057] After determining the optimal quenching parameters, they are applied to the actual cooling equipment to achieve precise control. A multi-angle adjustable nozzle system can be used, with the nozzle position and direction finely adjusted based on the parameters obtained from the simulation. This control strategy, by pre-determining and optimizing parameters, reduces uncertainties in the cooling process, ensures the uniformity of the temperature field, and thus provides a stable foundation for subsequent rapid cooling.

[0058] Meanwhile, during actual slow cooling, the online quenching method for metal profiles includes a real-time slow cooling control step: monitoring the average temperature T of the profile cross-section at the point where slow cooling is completed. avg When the average temperature of the profile section T avg Deviation from the center value of the target interval T target When the temperature is T0+25℃, adjust the cooling rate during slow cooling according to the following formula: ; Among them, V ref V is the reference cooling rate corresponding to the quenching parameters obtained from the simulation; adj The adjusted target cooling rate is represented by μ, which is the response coefficient ranging from 0.2 to 0.5. The cooling rate can be obtained by calculating the temperature at different time points monitored by the real-time temperature monitoring module. avg It is the average temperature at the section where the slow cooling is completed (i.e., the outlet of the slow cooling zone and the inlet of the fast cooling zone) of the profile section: T avg = (T1 + T2 + T3 + …… + Tn ) / n, where T1, T2, T3, ..., T n The measured temperature values ​​at different temperature measurement points on the same cross section of the metal profile obtained by multiple infrared temperature sensors in the real-time temperature monitoring module, where n is the number of infrared temperature sensors or temperature measurement points.

[0059] Target interval center value T target It is the center value of the ideal cross-sectional average temperature range expected to be reached at the end of the slow cooling stage. This range is usually set as [T0, T0+50℃], and its center value is T. target =T0+25℃. The goal of slow cooling control is to adjust the cooling rate in real time to keep the average temperature T of the profile section below T. avg The target temperature range should be kept as stable as possible around this central value to ensure a uniform temperature field during the subsequent rapid cooling phase. The target range's central value is T. target Defined as T0+25℃, this setting is based on a combination of scientific considerations and practical balance. Firstly, from the perspective of process window optimization, setting the target temperature for slow cooling above T0 ensures that the overall temperature of the profile remains above the critical point where significant mechanical property loss begins before water cooling, thus completely avoiding unexpected performance loss during the slow cooling stage. Secondly, the +25℃ offset provides a sufficiently large and safe operating window, allowing for some temperature fluctuations without immediately reaching the performance inflection point, enhancing process robustness. Finally, from the perspective of control response effectiveness, setting T0+25℃... target Setting the temperature at the center of the range results in a smoother control response, enabling the temperature to be quickly and proportionally pulled back to the target range, achieving a uniform and stable temperature field.

[0060] By combining simulation and optimization, the challenge of precisely controlling temperature distribution in traditional cooling methods can be overcome. Compared to setting cooling parameters solely based on experience, using simulation software for analysis can significantly improve the accuracy of the cooling process, reduce the number of trials and adjustments, and lower production costs. Software simulation can also help identify and solve potential cooling problems, especially in the cooling process of complex cross-section profiles, where precise control of the temperature field becomes more reliable.

[0061] Specifically, the air-cooling and / or mist-cooling process of the metal profile is simulated using simulation software to determine the quenching parameters for the metal profile. This includes the following steps: Simulating the air-cooling and / or mist-cooling process of the metal profile using simulation software to determine the cross-sectional temperature distribution when the lowest cross-sectional temperature at the point where the slow cooling is completed reaches the quenching inflection point temperature T0; determining whether the cross-sectional temperature distribution is within the range of T0 to T0+50℃; if the cross-sectional temperature distribution does not meet the range of T0 to T0+50℃, adjusting the quenching parameters based on the simulation results; and re-simulating based on the adjusted quenching parameters until the cross-sectional temperature distribution at the point where the slow cooling is completed is within the range of T0 to T0+50℃.

[0062] In practice, simulation software (such as QForm or ANSYS) is first used to simulate the air-cooling and / or mist-cooling process of the metal profile. The core of the simulation is to observe and analyze the temperature field distribution of the profile cross-section, especially the overall temperature change when the lowest cross-sectional temperature reaches T0 at the point where the profile has completed slow cooling. When the lowest temperature of the profile reaches T0, the temperature distribution of its cross-section must be maintained within the range of T0 to T0+50℃ to ensure uniform cooling and avoid performance degradation or material deformation caused by excessively fast or slow cooling.

[0063] In actual simulations, the simulation software calculates and displays the temperature field distribution of the profile cross-section based on preset quenching parameters, such as the flow rate, wind speed, spray angle, and spatial position of the air-cooled nozzle. It also outputs cooling rate curves for key locations (such as the thickest and thinnest points of the cross-section). Through simulation, the baseline cooling rate V during the slow cooling stage can be obtained and optimized. ref The benchmark cooling rate V ref This forms the basis for subsequent real-time control. If the simulation results show that the temperature in certain areas is not within the range of T0~T0+50℃, it indicates that the current quenching parameters cannot achieve ideal temperature control and require further adjustment. This adjustment process may include increasing or decreasing the flow rate of air cooling and / or mist cooling, changing the spray angle of air cooling and / or mist cooling nozzles, or redistributing the positions of air cooling and / or mist cooling devices. Adjusting these parameters is not only to achieve the desired temperature distribution, but also to increase the cooling rate V in critical areas. ref The quenching parameters are optimized to a reasonable range, effectively suppressing deformation during the high-temperature stage while preserving sufficient supercooling for subsequent water cooling. The adjusted quenching parameters are then input into simulation software for a new round of simulation to observe the modified cooling effect. If the temperature distribution still does not meet the requirements, adjustments and simulations continue until the temperature field distribution of the profile cross-section fully meets the requirements. Through this simulation and optimization, the cooling intensity (reference cooling rate V) during the slow cooling stage is optimized. refThe cooling rate is precisely "anchored" within a scientific range, avoiding problems such as excessive early internal stress due to an excessively high cooling rate, or excessively long slow cooling time and reduced production efficiency due to an excessively low cooling rate. Secondly, the optimized baseline cooling rate V... ref As a reference value for the real-time control formula, it ensures the accuracy of subsequent online adjustments (V). adj The starting point is scientific and stable, which greatly improves the response accuracy and reliability of the entire adaptive control system. Ultimately, this proactive design and control of the cooling rate is the key technical guarantee for achieving the dual goals of "ensuring performance" and "controlling deformation", enabling the entire quenching process to shift from experience-based to model-driven, improving process consistency and product yield.

[0064] S103: The metal profile that has undergone slow cooling is quenched by water cooling to cool it to room temperature.

[0065] It should be noted that the purpose of step S103 is to rapidly cool the profile, which has been slowly cooled to a specific temperature range, using water cooling (the water cooling medium temperature is 5~25℃), thereby achieving a quenching effect and ensuring that the metal profile has ideal mechanical properties and dimensional stability. Rapidly lowering the profile temperature through rapid cooling causes corresponding changes in the internal microstructure of the material, such as the precipitation of alloying elements in the solid solution to form strengthening phases, thus significantly improving the strength and hardness of the material.

[0066] At high temperatures, metallic materials have low yield strength and are prone to plastic deformation due to thermal stress generated by rapid cooling. Therefore, this invention first uses air cooling to slowly lower the temperature, uniformly controlling the temperature field within the range of T0 to T0+50℃. This helps to reduce the temperature gradient inside the material, reduce thermal stress concentration, and thus reduce the risk of deformation.

[0067] When the profile temperature approaches the quenching inflection point temperature T0, the material's yield strength has already increased, allowing it to withstand faster cooling rates. At this point, switching to water cooling and / or mist cooling methods can achieve the desired quenching effect through rapid cooling, which can promote the transformation of the material's internal microstructure, forming a strengthening phase and thus improving mechanical properties.

[0068] In one exemplary embodiment, the metal profile that has undergone slow cooling is quenched by water cooling to cool it to room temperature. Specifically, the following steps are included: using simulation software to perform online water quenching simulation on the metal profile that has undergone slow cooling, adjusting the water quenching parameters so that the temperature difference of the metal profile cross section is between 5°C and 10°C, and so that the metal profile that has undergone slow cooling is cooled to room temperature within 10 seconds.

[0069] Meanwhile, during actual water cooling, the online quenching method for metal profiles includes a slow cooling real-time control step: controlling the cooling rate V of the slowest cooling region on the cross-section of the metal profile. q satisfy: ; Among them, V crit The minimum critical cooling rate required to cool a slowly cooled metal profile to room temperature; T entry This represents the region on the cross-section where cooling is slowest during water cooling of the metal profile; λ is an adjustment coefficient, ranging from 0.1 to 0.3; T room At room temperature. (T) entry This refers to the temperature of the slowest-cooling region (T) on the cross-section of a metal profile when it enters the rapid cooling zone (water cooling zone). This region is typically the thickest part of the cross-section, an area difficult for the cooling medium to reach, or a region with a complex geometry. The region with the highest temperature within the same cross-section, identified by an infrared temperature sensor in the real-time temperature monitoring module, is the slowest-cooling region (T). entry .

[0070] By quantitatively controlling the cooling rate of the slowest cooling zone, the necessary quenching strength is ensured for the entire profile cross-section, even in the most unfavorable cooling areas. This guarantees that alloying elements in the aluminum alloy are fully retained in the supersaturated solid solution, preparing for subsequent aging precipitation and ensuring the mechanical properties of the aluminum profile. Simultaneously, this control strategy considers the actual temperature T of the metal profile when it enters the water-cooling process. entry Room temperature T room and the critical cooling rate V of the material crit This leads to an adaptive control strategy based on actual working conditions. The adjustment coefficient λ in the formula provides flexibility for process optimization, allowing for fine-tuning based on factors such as specific alloy grades and profile cross-sectional complexity. This achieves scientific adjustment of cooling intensity, ensuring quenching effect while minimizing the risk of cross-sectional temperature differences and deformation caused by uneven cooling, thus improving process stability and repeatability. Specifically, the larger the value of λ, the higher the required cooling rate V. q The higher the value of λ, the stronger the cooling intensity; the smaller the λ value, the lower the required cooling rate V. q The lower the value, the more moderate the cooling intensity. However, when the cross-sectional structure is more complex, the cooling medium may have difficulty reaching certain areas, leading to greater differences in cooling rates across different parts of the cross-section. The cooling rate of the slowest-cooling areas may be significantly lower than the average level, in which case the value of λ should be appropriately increased.

[0071] During water quenching, the profile undergoes a process of decreasing from the initial slow cooling temperature to room temperature. During this process, the difference between the highest and lowest temperatures at the profile cross-section should not exceed 10°C, and this process should not exceed 10 seconds. Cooling uniformity can be maintained by adjusting the water-cooling nozzles to prevent over-quenching deformation of the profile. The 10-second time limit for decreasing the temperature to room temperature during slow cooling ensures that the alloying elements in the quenched aluminum alloy remain in a supersaturated solid solution, preparing for subsequent aging precipitation and ensuring the mechanical properties of the aluminum profile.

[0072] Please refer to Figure 2 As shown, one embodiment of the present invention also provides a quenching device for the aforementioned online quenching method for metal profiles. The quenching device includes: a control module, a real-time temperature monitoring module, and a slow cooling zone and a fast cooling zone arranged sequentially along the extrusion direction of the metal profile. The slow cooling zone is used for air cooling and / or mist cooling of the extruded metal profile, ensuring that the temperature distribution of the cross-sectional temperature field at the slow cooling position of the metal profile is between T0 and T0+50℃. The fast cooling zone is used for water cooling of the air-cooled and / or mist-cooled metal profile. The real-time temperature monitoring module is used to monitor the temperature of the metal profile. The control module is connected to the cooling equipment (nozzles, fans, etc.) and the real-time temperature monitoring module. The control module is used to acquire the temperature of the metal profile and adjust the nozzles based on the temperature monitoring results.

[0073] The slow cooling zone is used for air cooling and / or mist cooling of the freshly extruded metal profile. This ensures that the temperature distribution of the cross-sectional temperature field at the point where the metal profile completes slow cooling (i.e., the position where the metal profile enters the fast cooling zone after completing slow cooling) is between T0 and T0+50℃. This section is designed because the metal profile is at a high temperature immediately after extrusion. Immediately using drastic cooling methods, such as water cooling or spray cooling, may cause internal stress concentration or severe deformation of the material, seriously affecting the dimensional accuracy of the profile. Therefore, the slow cooling zone uses air cooling to gradually lower the temperature of the profile surface. The relatively gentle air cooling and / or mist cooling process helps to control the temperature gradient within an acceptable range, thereby reducing internal stress caused by drastic temperature changes.

[0074] Air-cooling equipment may include multiple adjustable air-cooling nozzles or fan arrays. These devices can be adjusted according to the shape and wall thickness differences of the profile cross-section to achieve uniform distribution of cooling effect and control of cooling rate. This design not only effectively mitigates the rapid cooling shock of high-temperature materials, but also provides a temperature basis for subsequent cooling processes, enabling the profile to have a more uniform temperature field when entering the next stage of cooling.

[0075] The rapid cooling zone is used to further cool the slowly cooled metal profiles, such as through water cooling. The rapid cooling zone is designed to further reduce the profile's temperature to achieve a quenching effect and lock in the material's microstructure. Water cooling uses high-pressure water to quickly remove heat, making it suitable for applications requiring rapid and significant cooling. It can significantly improve the cooling rate and ensure the profile's quenching strength.

[0076] The slow cooling zone provides a buffer phase, gradually reducing the temperature of the profile and alleviating stress distribution within the material, laying the foundation for subsequent rapid cooling. The rapid cooling zone, on the other hand, is responsible for quickly completing the cooling process within a relatively low temperature range, ensuring the material's quenching strength and hardness. In this way, the entire cooling process achieves a gradual change from slow to rapid, avoiding deformation caused by excessively rapid cooling while meeting the mechanical performance requirements of the metal profile.

[0077] The independent control systems for the two cooling zones can be optimized and adjusted according to the different needs of the profiles. For example, during the production process, air cooling, water cooling, and mist cooling methods can be flexibly switched or combined according to the material properties and cross-sectional complexity, thereby improving the adaptability of the equipment, meeting the production requirements of various complex profiles, and improving overall production efficiency and product qualification rate.

[0078] In one exemplary embodiment, a slow cooling zone and a fast cooling zone form a cooling channel 35 through which a metal profile can pass. The cooling channel 35 is surrounded by nozzles 34 for spraying cooling medium. The angle and flow rate of the nozzles 34 are adjustable.

[0079] The cooling channel 35, consisting of a slow cooling zone and a fast cooling zone, ensures that the metal profile can pass through smoothly and receive continuous and efficient cooling. This cooling channel 35 surrounds the metal profile, forming a closed or semi-closed structure. This design ensures efficient flow of the cooling medium within the channel while reducing interference from the external environment, thus achieving more stable and precise temperature control.

[0080] Adjustable nozzles 34 are evenly distributed around the cooling channel 35. These nozzles 34 can be uniformly distributed along the four main directions of the channel, forming a three-dimensional cooling network. This omnidirectional arrangement ensures that the cooling medium covers the entire profile cross-section, achieving uniform cooling regardless of the profile's shape or wall thickness. The nozzle 34 design allows for free adjustment of angle and flow rate. By adjusting the nozzle 34 angle, the spray direction of the cooling medium can be precisely controlled, ensuring that the cooling medium directly hits the profile surface or specific areas, thereby achieving efficient localized cooling. Simultaneously, the adjustable flow rate of the nozzles 34 allows the system to precisely control the supply of cooling medium according to actual cooling needs, thus avoiding over- or under-cooling.

[0081] In one exemplary embodiment, please refer to Figure 3a and Figure 3b As shown, the quenching device includes a bottom support 31 and a top support 32. The top support 32 has downwardly extending mounting plates 33 on its left and right sides. The top of the bottom support 31, the bottom of the top support 32, and the mounting plates 33 are all provided with nozzles 34 facing the cooling channel 35.

[0082] The bottom support 31 serves as the foundation of the entire device, providing stability and load-bearing capacity. Its top is equipped with nozzles 34, which face the cooling channels 35 to spray cooling media onto the area beneath the profile, ensuring uniform and stable cooling at the bottom. The design of the bottom support 31 considers the device's center of gravity and stability, enabling the entire cooling system to remain stable under high-pressure water or high-speed airflow, preventing displacement or vibration due to the impact of the cooling media, thus guaranteeing the accuracy and stability of the cooling process. The cooling channels 35, arranged along the extrusion direction of the profile, sequentially include slow-cooling and fast-cooling zones.

[0083] The top bracket 32 ​​is located above the cooling channel 35, providing additional support and structural rigidity for the cooling system. Mounting plates 33 extending downwards are located on both sides of the top bracket 32. These mounting plates 33 are designed to extend vertically, allowing the nozzles 34 to be installed at an optimal angle, facing the top and sides of the profile within the cooling channel 35. This arrangement ensures that the cooling medium can cover the entire cross-section of the profile, achieving uniform cooling across the bottom, top, and side areas.

[0084] Nozzles 34 are distributed on the top of the bottom bracket 31, the bottom of the top bracket 32, and the left and right mounting plates 33, forming a comprehensive cooling network. This three-dimensional arrangement allows the cooling medium to act on the profile simultaneously from different directions, thereby achieving a comprehensive and uniform cooling effect. Each nozzle 34 can be adjusted in terms of flow rate and angle to adapt to different cross-sectional characteristics of the profile.

[0085] Specifically, the bottom support 31 is provided with a support seat 36 for supporting the metal profile. The bottom support 31 is connected to the lifting mechanism 37 and can be raised and lowered under the drive of the lifting mechanism 37. The support seat 36 is provided with rollers 38 for supporting the metal profile to feed along the extrusion direction. The main function of the support seat 36 is to provide reliable support and positioning for the metal profile passing through the cooling channel 35, ensuring that the profile remains stable during the cooling process.

[0086] To further enhance the flexibility and adaptability of the cooling system, the bottom bracket 31 is connected to a lifting mechanism 37 and can move up and down under the drive of the lifting mechanism 37. Through the lifting mechanism 37, the support base 36 can be adjusted according to different metal profile heights, thereby ensuring that the distance between the nozzle 34 and the profile is always within the optimal cooling range.

[0087] Example 1 This embodiment provides an online quenching method for aluminum alloy extruded profiles, the specific steps of which are as follows: The selected grade is 6D10, and the cross-sectional shape is as follows: Figure 4 The aluminum alloy profile 4 shown is used as the experimental material. The aluminum alloy profile 4 can be used in lightweight automotive parts, such as for manufacturing control arms, steering knuckles, and subframes.

[0088] S1: Obtain the quenching inflection point temperature T0 that affects the mechanical properties of the profile. Six groups of extruded samples of this grade were solution treated at 555℃ for 1 h. Then, the six groups of samples were air-cooled to 520℃, 480℃, 440℃, 400℃, 360℃, and 300℃ respectively, rapidly water-quenched, and then aged at 175℃ for 8 h. Finally, the Vickers hardness of each group of samples was measured.

[0089] The quenching inflection point temperature T0 of the metal profile is obtained based on the mechanical properties of the sample, specifically including the following steps: Calculate the mechanical property loss rate at each target temperature according to the following formula. : ; In the formula, P i P represents the mechanical property value (Vickers hardness) of each sample. max P represents the highest mechanical property value (highest Vickers hardness value) among all samples. min The lowest mechanical property value (lowest Vickers hardness value) for each sample; plot the mechanical property loss rate L. i With target temperature T i The relationship curve will not exceed the set threshold L for performance loss rate. th =10% maximum mechanical property loss rate L i The corresponding temperature point is determined to be the quenching inflection point temperature T0, based on Figure 6 The Vickers hardness test results shown indicate that the Vickers hardness of the samples quenched and aged to below 400 ℃ was significantly reduced, and the mechanical property loss rate exceeded 10%. Therefore, the quenching inflection point temperature T0 that affects the mechanical properties of the profile was determined to be 400 ℃.

[0090] S2: Use simulation software to simulate the online quenching of extruded profiles in the slow cooling zone. Specifically, the following steps are included: Use simulation software to simulate the air cooling and mist cooling process of the metal profile, determine the cross-sectional temperature distribution when the lowest cross-sectional temperature at the slow cooling position of the metal profile reaches the quenching inflection point temperature T0=400℃, and determine whether the cross-sectional temperature distribution is within the range of 400℃~450℃. By adjusting the quenching parameters such as the flow rate intensity and distribution position of the nozzle, the cross-sectional temperature distribution of the profile at the outlet position of the slow cooling zone is between 400℃ and 450℃.

[0091] Simultaneously, during the actual slow cooling process, a real-time slow cooling control step is implemented: monitoring the average temperature T of the profile cross-section at the point where slow cooling is completed. avg When the average temperature of the profile section T avg Deviation from the center value of the target interval T target When T0 + 25℃ = 425℃, adjust the cooling rate during slow cooling according to the following formula: Among them, V ref V is the reference cooling rate corresponding to the quenching parameters obtained from the simulation; adj The adjusted target cooling rate; The response coefficient is 0.3.

[0092] S3: Use simulation software to simulate the online quenching of extruded profiles in the rapid cooling zone. By adjusting the water quenching parameters (nozzle position, spray intensity, spray angle, etc.), the temperature difference of the metal profile cross section is kept between 5℃ and 10℃, and the profile is cooled to room temperature within 10 seconds after entering the rapid cooling zone inlet.

[0093] Simultaneously, in the actual water cooling process, real-time water cooling control steps are implemented: controlling the cooling rate V of the slowest cooling area on the metal profile cross-section. q satisfy: Among them, V crit T is the minimum critical cooling rate required to cool a slowly cooled metal profile to room temperature. entry This is the area on the cross-section of a metal profile that cools the slowest during water cooling. The adjustment factor is set to 0.2, T. room The room temperature is 20°C.

[0094] S4: Using the quenching device provided by this invention, extrusion trial production was carried out according to the parameters and real-time cooling rate control method used in the simulation in the above steps, and tensile properties were tested according to GB / T 228.1-2010.

[0095] Example 2 The method is basically the same as that described in Example 1, except that grade 7075 is used and the cross-sectional shape is as follows. Figure 5 The aluminum alloy profile 5 shown was tested, and the quenching inflection point temperature T0, which affects the mechanical properties of the profile, was measured as shown in the attached figure. Figure 6 As shown, the temperature is 440℃. Aluminum alloy profile 5 is mainly used in high-stress, lightweight applications, such as manufacturing high-stress components like aircraft fuselage frames, wing spars, and keel beams.

[0096] Comparative Example 1 Using the same alloy and cross-sectional shape as in Example 1, and keeping the nozzle position, spray angle, and flow rate unchanged, online quenching was performed using full-process air cooling.

[0097] Comparative Example 2 Using the same alloy and cross-sectional shape as in Example 1, and keeping the nozzle position, spray angle, and flow rate unchanged, online quenching was performed using full-process water cooling.

[0098] Comparative Example 3 Using the same alloy and cross-sectional shape as in Example 2, and keeping the nozzle position, spray angle, and flow rate unchanged, online quenching was performed using full-process air cooling.

[0099] Comparative Example 4 Using the same alloy and cross-sectional shape as in Example 2, and keeping the nozzle position, spray angle, and flow rate unchanged, online quenching was performed using full-process water cooling.

[0100] Comparative Example 5 Using the same alloy and cross-sectional shape as in Example 1, keeping the nozzle position, spray angle and flow rate unchanged, the online quenching method combining air cooling and water cooling provided by this invention is used, but temperature monitoring and real-time control of cooling rate are not performed during the slow cooling process, and fixed cooling is performed only according to the basic parameters obtained from simulation.

[0101] Comparative Example 6 Using the same alloy and cross-sectional shape as in Example 1, while keeping the nozzle position, spray angle, and flow rate constant, the online quenching method combining air cooling and water cooling provided by this invention is used. However, during the water cooling process, the cooling rate is not controlled in real time using a formula, but is fixedly cooled according to the basic parameters obtained from simulation.

[0102] Comparative Example 7 Using the same alloy and cross-sectional shape as in Example 2, keeping the nozzle position, spray angle and flow rate unchanged, the online quenching method combining air cooling and water cooling provided by this invention is used, but temperature monitoring and real-time control of cooling rate are not performed during the slow cooling process, and fixed cooling is performed only according to the basic parameters obtained from simulation.

[0103] Comparative Example 8 Using the same alloy and cross-sectional shape as in Example 2, and keeping the nozzle position, spray angle and flow rate unchanged, the online quenching method combining air cooling and water cooling provided by this invention is used. However, during the water cooling process, the cooling rate is not controlled in real time using a formula, but is fixedly cooled according to the basic parameters obtained from simulation.

[0104] Comparative Example 9 Using profiles with the same alloy and cross-sectional shape as in Example 1, the online quenching method combining air cooling and water cooling provided by this invention was used. However, no real-time control was performed during the entire quenching process, including the cooling rate control during the slow cooling and water cooling stages. The cooling was performed only according to the basic parameters obtained from the simulation.

[0105] Comparative Example 10 Using the same alloy and cross-sectional shape as in Example 2, the online quenching method combining air cooling and water cooling provided by this invention was used. However, no real-time control was performed during the entire quenching process, including the cooling rate control during the slow cooling and water cooling stages. The cooling was fixed only according to the basic parameters obtained from the simulation.

[0106] For the above embodiments and comparative examples, the deformation displacement of the profile along the cross-sectional direction was recorded every 1m according to the length of the extruded profile, and the absolute average deformation displacement was statistically analyzed. The results are shown in Table 1.

[0107] Table 1 As shown in Table 1, compared to Comparative Examples 2 and 4 which were water-cooled throughout the process, the quenching deformation degree of Examples 1 and 2 was significantly improved, while the decrease in mechanical properties was minimal, meeting the requirements for practical use. Compared to Comparative Examples 5-10, Examples 1 and 2 further demonstrated the comprehensive advantages of the slow cooling and real-time water cooling control mechanism. Among them, the deformation degree of Comparative Examples 5 and 7 without real-time slow cooling control was lower than that of Comparative Examples 2 and 4, but significantly higher than that of Examples 1 and 2, and the mechanical properties decreased, indicating that temperature monitoring and control during the slow cooling stage is crucial to ensuring the uniformity of cross-sectional temperature. The deformation control of Comparative Examples 6 and 8 without real-time water cooling control was better than that of the method in Examples 1 but worse than that of Examples 2, and the mechanical properties were not optimal, verifying the necessity of real-time control based on the aforementioned formula during the water cooling stage for balancing quenching strength and deformation suppression. Comparative Examples 9 and 10 without any real-time control showed the worst performance, with the largest deformation and the lowest strength, fully demonstrating the irreplaceable synergistic effect of the slow cooling and real-time water cooling control steps of the present invention. On the other hand, although the degree of quenching deformation in Examples 1 and 2 was greater than that in Comparative Examples 1 and 3 (full-process air cooling), the yield strength of Comparative Examples 1 and 3 (full-process air cooling) decreased significantly, which did not meet the requirements for use. Furthermore, the data from Comparative Examples 5-10 further showed that none of the solutions lacking the real-time control strategy of the present invention could simultaneously take into account both mechanical properties and dimensional stability.

[0108] In summary, this invention divides the cooling stages by the quenching inflection point temperature and innovatively introduces a real-time control mechanism for slow cooling and water cooling. This enables dynamic and precise control of the cooling rate and uniform management of the temperature field. It can quantify temperature deviations into cooling parameter adjustments, achieving a fundamental shift from traditional experience-based operation to data-driven control. This significantly improves process stability and reproducibility, ultimately achieving an optimal balance among multiple objectives such as ensuring mechanical performance, controlling deformation, and improving production efficiency. This provides reliable technical support for the high-end manufacturing of high-quality metal profiles.

[0109] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0110] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A method for online quenching of metal profiles, characterized in that, Includes the following steps: Obtain the quenching inflection point temperature T0 of the metal profile; The metal profile is slowly cooled by air cooling and / or mist cooling, so that the temperature distribution of the cross-sectional temperature field at the location where the metal profile has been slowly cooled is between T0 and T0+50℃. The metal profiles that have undergone slow cooling are quenched in water to cool them to room temperature.

2. The online quenching method for metal profiles according to claim 1, characterized in that, To obtain the quenching inflection point temperature T0 of a metal profile, the following steps are included: Multiple samples of the same grade as the metal profile were subjected to solution treatment; After solution treatment, multiple samples were gradually cooled to different target temperatures by air cooling, and then water quenched to room temperature. Peak aging treatment was performed on multiple samples after water quenching, and then the mechanical properties of each sample were tested. The quenching inflection point temperature T0 of the metal profile was obtained based on the mechanical properties of the samples.

3. The online quenching method for metal profiles according to claim 2, characterized in that, The method for obtaining the quenching inflection point temperature T0 of the metal profile based on the mechanical properties of the sample includes the following steps: The mechanical property loss rate L at each target temperature is calculated using the following formula. i : ； In the formula, P i P represents the mechanical property value of each sample. max P represents the highest mechanical property value among all samples. min This represents the lowest mechanical property value among all samples. Plot the mechanical performance loss rate L i With target temperature T i The relationship curve will not exceed the set threshold L for performance loss rate. th Maximum mechanical property loss rate L i The corresponding temperature point is determined as the quenching inflection point temperature T0, where the performance loss rate is set to a threshold L. th The value range is 5% to 20%.

4. The online quenching method for metal profiles according to claim 2, characterized in that, The multiple samples are arranged in a target temperature gradient for air cooling, and the temperature difference between two adjacent target temperatures is 5℃~60℃.

5. The online quenching method for metal profiles according to claim 1, characterized in that, The metal profile is slowly cooled using air cooling and / or mist cooling, so that the temperature distribution of the cross-sectional temperature field at the location where the slow cooling is completed is between T0 and T0+50℃. This includes the following steps: The air cooling and / or mist cooling process of metal profiles is simulated using simulation software to determine the quenching parameters of the metal profiles. The metal profile is slowly cooled according to the quenching parameters, so that the temperature distribution of the cross-sectional temperature field at the location where the slow cooling is completed is between T0 and T0+50℃.

6. The online quenching method for metal profiles according to claim 5, characterized in that, The online quenching method for metal profiles includes a slow cooling real-time control step: Monitor the average temperature T of the profile section at the point where the slow cooling of the metal profile is completed. avg When the average temperature of the profile section T avg Deviation from the center value of the target interval T target At T0+25℃, based on the quenching parameters determined by simulation, adjust the cooling rate during slow cooling according to the following formula: ； Among them, V ref V is the reference cooling rate corresponding to the quenching parameters obtained from the simulation; adj The adjusted target cooling rate; μ is the response coefficient, ranging from 0.2 to 0.

5.

7. The online quenching method for metal profiles according to claim 5, characterized in that, The air-cooling and / or mist-cooling process of metal profiles is simulated using simulation software to determine the quenching parameters of the metal profiles, including the following steps: Simulation software was used to simulate the air cooling and / or mist cooling process of metal profiles to determine the cross-sectional temperature distribution when the lowest cross-sectional temperature at the location where the slow cooling is completed reaches the quenching inflection point temperature T0. Determine whether the cross-sectional temperature distribution is within the range of T0~T0+50℃; If the cross-sectional temperature distribution does not meet the range of T0~T0+50℃, adjust the quenching parameters according to the simulation results; Based on the adjusted quenching parameters, the simulation was repeated until the cross-sectional temperature distribution at the location where the metal profile had completed slow cooling was within the range of T0~T0+50℃.

8. The online quenching method for metal profiles according to claim 1, characterized in that, The process of water quenching the slowly cooled metal profile to room temperature includes: Online water quenching simulation was performed on the metal profiles that had undergone slow cooling using simulation software. By adjusting the water quenching parameters, the temperature difference between the metal profile sections was kept between 5°C and 10°C, and the metal profiles that had undergone slow cooling were cooled to room temperature within 10 seconds.

9. The online quenching method for metal profiles according to claim 8, characterized in that, The online quenching method for metal profiles includes a real-time water cooling control step: Controlling the cooling rate V of the slowest cooling region on the cross-section of the metal profile q satisfy: ； Among them, V crit The minimum critical cooling rate required to cool a slowly cooled metal profile to room temperature; T entry This represents the region on the cross-section where cooling is slowest during water cooling of the metal profile; λ is an adjustment coefficient, ranging from 0.1 to 0.3; T room Room temperature.

10. A quenching apparatus for the online quenching method of metal profiles according to any one of claims 1 to 9, characterized in that, include: A slow cooling zone and a fast cooling zone are arranged sequentially along the extrusion direction of the metal profile; the slow cooling zone is used to air cool and / or mist cool the extruded metal profile, so that the temperature distribution of the cross-sectional temperature field at the position where the slow cooling is completed is between T0 and T0+50℃; the fast cooling zone is used to water cool the metal profile after air cooling and / or mist cooling.

11. The quenching apparatus according to claim 10, characterized in that, The slow cooling zone and the fast cooling zone form a cooling channel through which the metal profile can pass. The cooling channel is surrounded by nozzles for spraying cooling medium, and the angle and flow rate of the nozzles are adjustable.

12. The quenching apparatus according to claim 11, characterized in that, The quenching device includes a bottom support and a top support. The top support has downward-extending mounting plates on its left and right sides. The top of the bottom support, the bottom of the top support, and the mounting plates are all provided with nozzles facing the cooling channel.

13. The quenching apparatus according to claim 12, characterized in that, The bottom support is provided with a support base for supporting the metal profile. The bottom support is connected to the lifting mechanism and can be lifted and lowered under the drive of the lifting mechanism. The support base is provided with rollers for supporting the metal profile to be fed along the extrusion direction.

14. The quenching apparatus according to claim 11, characterized in that, The quenching device includes a real-time temperature monitoring module, which is used to monitor the temperature of the metal profile.

15. The quenching apparatus according to claim 14, characterized in that, It includes a control module, which is connected to a nozzle and a real-time temperature monitoring module. The control module is used to acquire the temperature of the metal profile and adjust the nozzle based on the temperature monitoring results.

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