Machining control method for hot forming steel part and related equipment

Abstract

The invention discloses a processing control method of a hot forming steel part and related equipment, and relates to the technical field of stamping forming manufacturing, and the method comprises the following steps: carrying out temperature detection on different areas of a zinc-based coating hot forming steel plate material, and determining a temperature average value of each area, the zinc-based coating hot forming steel plate material comprises a first area and a second area, the first area and the second area are not overlapped, and the time that the first area enters a cooling roller is earlier than the time that the second area enters the cooling roller; based on the temperature average value of each area and a cooling roller parameter control model, the different areas are pre-cooled, a to-be-stamped steel plate is obtained, and cooling roller parameters corresponding to the cooling roller parameter control model comprise the cooling roller speed, the cooling roller temperature and the cooling water flow; and the to-be-stamped steel plate is subjected to stamping forming and pressure maintaining quenching, and the zinc-based coating hot forming steel part is obtained.

Description

Technical Field

[0001] This application relates to the technical field of stamping forming manufacturing, and particularly relates to a processing control method for hot-formed steel parts and related equipment. Background Art

[0002] Hot-formed steel is widely used in the manufacturing of automotive parts to meet the requirements of lightweight and high strength. These parts can significantly improve the anti-collision performance of vehicles. However, in traditional hot-formed steel production, scale is easily generated, resulting in die wear, and an additional shot peening process is required, increasing the complexity and cost of the production process. To solve this problem, aluminum-silicon coated hot-formed steel has been proposed, which improves corrosion resistance by adding a coating on the steel surface. However, the corrosion resistance of aluminum-silicon coated hot-formed steel is still insufficient in some special environments.

[0003] Zinc-based coated hot-formed steel has received extensive attention due to its excellent corrosion resistance and high strength. The zinc coating provides cathodic protection while preventing the oxidation of the substrate. However, the low melting point of zinc brings the risk of LME (Liquid Metal Embrittlement). In traditional hot stamping processes, zinc-based coated steel sheets need to be directly transferred to the stamping die after high-temperature austenitization treatment. The presence of liquid zinc in this process may lead to the propagation of microcracks in the substrate, ultimately resulting in part failure. Therefore, how to effectively control the forming temperature of zinc-based coated steel to reduce the LME risk has become an urgent problem to be solved. Summary of the Invention

[0004] A series of simplified concepts are introduced in the Summary of the Invention section, which will be further elaborated in the Detailed Description section. The Summary of the Invention section of this application does not mean to attempt to define the key features and essential technical features of the claimed technical solution, nor does it mean to attempt to determine the protection scope of the claimed technical solution.

[0005] In a first aspect, this application provides a processing control method for hot-formed steel parts, including:

[0006] Detecting the temperature of different regions of a zinc-based coated hot-formed steel sheet, and determining the average temperature of each region. Wherein, the zinc-based coated hot-formed steel sheet includes a first region and a second region, the first region and the second region do not overlap, and the time when the first region enters the cooling roll is earlier than the time when the second region enters the cooling roll;

[0007] Based on the average temperature of each region and the cooling roll parameter control model, pre-cooling the different regions to obtain a steel sheet to be stamped, where the cooling roll parameters corresponding to the cooling roll parameter control model include cooling roll speed, cooling roll temperature, and cooling water flow rate;

[0008] The above-mentioned steel sheet to be stamped is stamped and formed and then pressure-maintained and quenched to obtain a zinc-based coating hot-formed steel part.

[0009] In a feasible implementation manner, the roll speed of the above cooling roll is determined based on the following formula:

[0010]

[0011] where, T two，n is the average temperature of the nth sheet in the above second region after pre-cooling, T first，n is the average temperature of the nth sheet in the above first region after pre-cooling, V out，n is the final roll speed when the nth sheet leaves the cooling roll, V out，n+1 is the final roll speed when the (n + 1)th sheet leaves the cooling roll.

[0012] In a feasible implementation manner,

[0013] The initial roll speed V of the nth sheet in，n is a preset initial value;

[0014] When n = 1, the final roll speed V of the first sheet out，1 is a preset final value;

[0015] When n > 1, the final roll speed V of the nth sheet out，n is determined based on the final roll speed V of the previous sheet out，n-1 wherein, the final roll speed of the above cooling roll shows a downward trend as the number of sheets increases.

[0016] In a feasible implementation manner, the cooling water flow rate is determined based on the following formula:

[0017]

[0018] where, Q is the cooling water flow rate, H is the heat transfer amount, ρ is the density of the cooling water, C is the specific heat capacity of the cooling water, ΔT w is the temperature difference between the inlet and outlet of the cooling water;

[0019] The temperature of the above cooling roll is determined based on the following formula:

[0020]

[0021] where, T b is the temperature of the cooling roll, T i is the initial temperature of the cooling roll, Δx is the thickness of the cooling roll, k is the thermal conductivity, and A is the heat conduction area.

[0022] In a feasible implementation manner, before the temperature of different regions of the hot-formed steel sheet with a zinc-based coating is detected, it includes:

[0023] The hot-formed steel sheet with a zinc-based coating is subjected to austenitizing heat treatment, wherein the austenitizing heat treatment includes roller hearth furnace heating, box furnace heating, induction heating, and resistance heating.

[0024] In a feasible implementation manner,

[0025] The temperature difference between the pre-cooled sheet and the sheet before pre-cooling is within a first preset range, where the first preset range is greater than or equal to a first preset temperature and less than or equal to a second preset temperature.

[0026] In a feasible implementation manner, it further includes:

[0027] Before the stamping forming operation after the pre-cooling operation ends, the sheet is controlled to stand still for a first preset time so that the temperature of the sheet is lower than the preset stamping temperature.

[0028] In a second aspect, the present application provides a processing control device for hot-formed steel parts, including:

[0029] A temperature detection unit for detecting the temperature of different regions of the hot-formed steel sheet with a zinc-based coating and determining the average temperature of each region. The hot-formed steel sheet with a zinc-based coating includes a first region and a second region, the first region and the second region do not overlap, and the time when the first region enters the cooling roller is earlier than the time when the second region enters the cooling roller;

[0030] A sheet cooling unit for pre-cooling the different regions based on the average temperature of each region and a cooling roller parameter control model to obtain a steel sheet to be stamped. The cooling roller parameters corresponding to the cooling roller parameter control model include the cooling roller speed, the cooling roller temperature, and the cooling water flow rate;

[0031] A part forming unit for stamping and forming and pressure maintaining and quenching the steel sheet to be stamped to obtain a hot-formed steel part with a zinc-based coating.

[0032] In a third aspect, an electronic device includes: a memory, a processor, and a computer program stored in the memory and executable on the processor. The processor is used to implement the steps of the processing control method for hot-formed steel parts according to any one of the first aspects when executing the computer program stored in the memory.

[0033] In a fourth aspect, the present application further provides a computer-readable storage medium, on which a computer program is stored. The computer program, when executed by a processor, implements the processing control method for hot-formed steel parts according to any one of the first aspects.

[0034] In summary, the processing control method for zinc-based coating hot forming steel proposed in this application significantly improves the uniformity and efficiency of sheet cooling. By detecting the temperature distribution in different regions of the sheet and dynamically adjusting the parameters of the cooling roller, the temperature distribution after pre-cooling of the sheet can be accurately controlled to ensure the temperature uniformity of the sheet. In addition, based on the cooling roller speed optimization model with dynamic feedback regulation, the cooling roller can adapt to the cooling requirements of different sheets, reducing the energy consumption and temperature difference fluctuation during the cooling process. The processing control method of the present invention significantly reduces the mold entry temperature of zinc-based coating steel during hot stamping, effectively suppressing the occurrence of the LME phenomenon, thereby improving the forming quality and production reliability of parts. Compared with the traditional method, the method of the present invention not only has high production efficiency, but also can be directly applied to the existing production line, reducing the transformation cost and having broad industrial application prospects. Description of the Drawings

[0035] By reading the following detailed description of the preferred embodiments, various other advantages and benefits will become clear to those of ordinary skill in the art. The drawings are only for the purpose of illustrating the preferred embodiments and are not considered to be a limitation of this specification. Moreover, throughout the drawings, the same reference numerals are used to represent the same components. In the drawings:

[0036] Figure 1 It is a schematic flow chart of a processing control method for a hot forming steel part provided by an embodiment of this application;

[0037] Figure 2 It is a schematic structural diagram of a processing control device for a hot forming steel part provided by an embodiment of this application;

[0038] Figure 3 It is a schematic structural diagram of a processing control electronic device for a hot forming steel part provided by an embodiment of this application. Detailed Embodiments

[0039] The terms "first", "second", "third", "fourth", etc. (if any) in the description, claims, and the above-mentioned drawings of this application are used to distinguish similar objects and do not necessarily describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances so that the embodiments described here can be implemented in an order different from that shown or described here. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products, or devices. The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are only a part of the embodiments of this application, rather than all of the embodiments.

[0040] Please refer to Figure 1 , which is a schematic flowchart of a processing control method for a hot-formed steel part provided by an embodiment of this application, and specifically may include:

[0041] S110. Detect the temperature of different regions of a zinc-based coated hot-formed steel sheet, and determine the average temperature of each region. Among them, the zinc-based coated hot-formed steel sheet includes a first region and a second region, the first region and the second region do not overlap, and the time when the first region enters the cooling roll is earlier than the time when the second region enters the cooling roll;

[0042] Exemplarily, during the hot stamping forming process of a zinc-based coated hot-formed steel sheet, a certain temperature uniformity needs to be maintained to reduce the risk of LME. However, due to uneven temperature distribution in the heating furnace, complex sheet shape, and different degrees of heat exchange between different regions of the sheet and the external environment, there are often significant lateral and longitudinal distribution differences in the surface temperature of the sheet after it comes out of the furnace. If these temperature differences are not monitored and the subsequent cooling strategy is not adjusted, it may lead to uneven cooling and ultimately affect the forming quality.

[0043] By detecting the temperature of different regions of a zinc-based coated hot-formed steel sheet and obtaining the average temperature of each region, the temperature of the sheet directly affects the mechanical properties and forming behavior of the material. By detecting the temperature of different longitudinal and lateral regions of the sheet, the overall temperature distribution characteristics of the sheet can be accurately reflected, providing a reference basis for subsequent cooling treatment.

[0044] Use high-precision devices such as infrared thermal imaging devices or laser thermometers to collect the surface temperature of each area of the sheet metal in real time. The detected data includes key indicators such as the maximum value, minimum value, and average value, which are used to analyze the temperature gradient of the sheet metal. After data collection, the average temperature of different areas is calculated through a processing algorithm to ensure that the setting of the cooling roll parameters is more targeted.

[0045] S 120. Based on the average temperature of each above-mentioned area and the cooling roll parameter control model, perform pre-cooling treatment on the above-mentioned different areas to obtain the steel sheet to be stamped, wherein the cooling roll parameters corresponding to the cooling roll parameter control model include the cooling roll speed, the cooling roll temperature, and the cooling water flow rate;

[0046] Exemplarily, in the hot stamping process of zinc-based coated hot-formed steel, in order to effectively reduce the sheet metal temperature to the safe range and ensure cooling uniformity, the pre-cooling treatment is a key link. Step S120 performs precise pre-cooling treatment on different areas of the sheet metal based on the average temperature of each area and the cooling roll parameter control model to form the steel sheet to be stamped. This step realizes the dynamic balance of cooling efficiency and uniformity by optimizing the cooling roll parameters. It should be noted that in this embodiment, the safe range is not higher than 750 °C.

[0047] S130. Perform stamping forming and pressure maintaining quenching on the above-mentioned steel sheet to be stamped to obtain zinc-based coated hot-formed steel parts.

[0048] Exemplarily, the steel sheet to be stamped after pre-cooling treatment is transferred to the press die for stamping forming and pressure maintaining quenching. When the sheet metal enters the die, its temperature is strictly controlled below 750 °C to effectively inhibit the occurrence of substrate embrittlement caused by liquid zinc. During the stamping process, the press completes the precise forming of the part by setting reasonable pressure and pressure maintaining time, and at the same time performs pressure maintaining quenching in the die to improve the strength and tissue properties of the part. The finally obtained zinc-based coated hot-formed steel parts have excellent mechanical properties, surface quality, and corrosion resistance, providing a reliable guarantee for the production of high-strength and lightweight parts. It should be noted that in this embodiment, the pressure maintaining time can be set to 6 - 15 seconds.

[0049] In some examples, the above-mentioned cooling roll speed is determined based on the following formula:

[0050]

[0051] where T two，n is the average temperature of the second area of the nth sheet metal after pre-cooling, T first，n is the average temperature of the first area of the nth sheet metal after pre-cooling, V out，n is the termination roll speed of the nth sheet metal when it leaves the cooling roll, V out，n+1 is the termination roll speed of the (n + 1)th sheet metal when it leaves the cooling roll.

[0052] Among them, the initial roller speed V of the nth sheet in，n is a preset initial value;

[0053] In the case of n = 1, the final roller speed V of the first sheet out，1 is a preset final value;

[0054] In the case of n > 1, the final roller speed V of the nth sheet out，n is determined based on the final roller speed V of the previous sheet out，n-1 wherein, the final roller speed of the above cooling roller shows a downward trend with the increase in the number of sheets.

[0055] Exemplarily, the adjustment of the cooling roller speed is calculated by monitoring the temperature distribution in different regions of the sheet and combining the temperature difference gradient of the region. This dynamic adjustment mechanism ensures the uniformity of the sheet temperature and avoids forming problems caused by uneven temperature distribution.

[0056] In some examples, the above cooling water flow rate is determined based on the following formula:

[0057]

[0058] wherein, Q is the cooling water flow rate, representing the volume of water flowing through the cooling roller per unit time; H is the heat transfer amount, representing the total heat transferred from the sheet to the cooling water during the cooling process; ρ is the density of the cooling water, representing the mass of the cooling water per unit volume; C is the specific heat capacity of the cooling water, representing the heat required for a unit mass of the cooling water to increase by one unit of temperature; ΔT w is the temperature difference between the inlet and outlet of the cooling water, representing the change in the temperature of the cooling water during the process of flowing through the cooling roller;

[0059] Exemplarily, during the pre-cooling process, the heat transferred from the sheet to the cooling water is equal to the heat absorbed by the cooling water. Therefore, the flow rate of the cooling water can be determined by the heat conservation formula. The flow rate of the cooling water is inversely proportional to the temperature difference between the inlet and outlet. A larger temperature difference means that less water volume can achieve the same cooling effect, thereby reducing the consumption of the cooling water. The density and specific heat capacity of the cooling water are the physical properties of water, which affect the cooling capacity and flow rate calculation. For example, a cooling medium with a larger specific heat capacity can absorb more heat, thereby reducing the flow rate requirement. In practical applications, the calculation and adjustment of the cooling water flow rate will be dynamically adjusted according to the heat characteristics of the sheet, the cooling target, and the actual temperature measurement value to ensure cooling uniformity and efficiency.

[0060] The above cooling roller temperature is determined based on the following formula:

[0061]

[0062] wherein, T bis the temperature of the cooling roll, T i is the initial temperature of the cooling roll, representing the temperature before the cooling roll starts to cool; Δx is the thickness of the cooling roll, representing the influence of the physical size of the cooling roll on its heat conduction ability; k is the thermal conductivity, representing the heat conduction performance of the cooling roll material; A is the heat conduction area, representing the area of contact between the cooling roll and the sheet metal, used to characterize the effective contact range of heat transfer.

[0063] In some examples, before the temperature detection of different regions of the hot-formed steel sheet with zinc-based coating, it includes:

[0064] Austenitizing heat treatment is performed on the hot-formed steel sheet with zinc-based coating. Among them, the above austenitizing heat treatment methods include roller hearth furnace heating, box-type furnace heating, induction heating, and resistance heating.

[0065] Exemplarily, before the temperature detection of the hot-formed steel sheet with zinc-based coating, austenitizing heat treatment is required to achieve microstructure transformation and temperature uniformity. This process aims to transform the microstructure of the sheet into austenite with high plasticity and formability, while optimizing the temperature distribution, laying a foundation for subsequent pre-cooling and stamping processes. By controlling the type of heating furnace and its parameters, the sheet is heated to a temperature range of 810°C - 950°C and held for 3 - 10 minutes, preferably at a temperature of 870°C - 910°C and a holding time of 4 - 6 minutes. In addition, induction heating and resistance heating can also be used to achieve austenitization, which can be flexibly selected according to actual needs. Through this heat treatment, the temperature distribution of the sheet is more uniform, the microstructure properties are optimized, and the risk of LME in subsequent stamping is significantly reduced.

[0066] Austenitizing heat treatment not only provides stable initial temperature conditions for the sheet, but also directly affects the effects of pre-cooling and stamping processes. A uniform temperature distribution can improve the cooling efficiency of the cooling roll device, ensure that the temperature of the sheet when stamping into the die is lower than 750°C, thus avoiding the generation of microcracks, while improving the formability of the sheet and the quality of the parts. This process is an indispensable key link in the hot-formed steel process with zinc-based coating, significantly improving the stability and reliability of part production.

[0067] In some examples, it also includes:

[0068] The temperature difference between the sheet after pre-cooling and the sheet before pre-cooling is within a first preset range, where the first preset range is greater than or equal to a first preset temperature and less than or equal to a second preset temperature.

[0069] Exemplarily, in this embodiment, the first preset temperature can be set to 100 °C, and the second preset temperature can be set to 200 °C. During the pre-cooling process of the zinc-based coated hot-formed steel, it is necessary to strictly control the temperature difference of the sheet before and after pre-cooling to ensure that the temperature difference is within the range of 100 °C to 200 °C. The setting of this temperature difference range aims to balance the relationship between the cooling effect and the sheet properties. If the temperature difference is less than 100 °C, insufficient cooling may cause the sheet temperature to not drop below 750 °C, increasing the risk of LME; when the temperature difference exceeds 200 °C, too fast cooling may cause thermal stress and microstructural changes, thereby affecting the forming quality and mechanical properties of the sheet. By an appropriate temperature difference range, the local temperature gradient can be effectively reduced to ensure a more uniform temperature distribution of the sheet.

[0070] This temperature difference control is achieved by dynamically adjusting relevant parameters of the cooling roll, such as roll speed, cooling water flow rate and flow volume, etc. The real-time temperature monitoring device detects the temperature distribution of the sheet before and after leaving the furnace, and feeds back the temperature difference to the control model for adjusting the operating parameters of the cooling roll. If the temperature difference deviates from the preset range, the system will automatically adjust the operating state of the cooling roll to correct the cooling effect. Through this process, both the cooling uniformity can be ensured and a balance can be achieved between production efficiency and quality.

[0071] Controlling the temperature difference within the range of 100 °C to 200 °C has an important impact on the hot forming process and part quality. An appropriate temperature difference ensures that the sheet can maintain a uniform and moderate temperature during stamping forming, effectively avoiding the LME phenomenon, and at the same time providing stable initial conditions for subsequent pressure holding and quenching. Examples show that this control design can significantly improve the forming quality and production stability of parts, and is an important guarantee for the pre-cooling process of zinc-based coated hot-formed steel.

[0072] In some examples, it further includes:

[0073] Before the stamping forming operation after the pre-cooling operation ends, control the sheet to be static for a first preset time so that the sheet temperature is less than the preset stamping temperature, where the above-mentioned first preset time is 2 seconds and the above-mentioned preset stamping temperature is 750 °C.

[0074] Exemplarily, in the process of zinc-based coated hot-formed steel, after the pre-cooling operation ends and before the stamping forming operation, a static time of 2 seconds is set and the sheet temperature is controlled to be lower than the preset stamping temperature of 750 °C. The core purpose of this design is to ensure that the sheet can reach a uniform and moderate temperature distribution before entering the stamping die, thereby effectively avoiding the occurrence of the phenomenon of liquid zinc-induced substrate embrittlement. The static process allows the internal thermal stress of the sheet to be relieved, and at the same time further balances the temperature gradient on the surface of the sheet, providing ideal temperature conditions for stamping forming. An appropriate static time not only ensures a safe temperature, but also improves the plasticity and forming accuracy of the sheet.

[0075] The setting of the standing time is combined with the sheet thickness, initial temperature and cooling method, generally ranging from a few seconds to dozens of seconds. Through real-time temperature monitoring equipment, ensure that the temperature of the sheet at the end of standing is less than 750 °C. If the temperature does not meet the requirements, it can be corrected by adjusting the standing time or supplementing cooling. This process needs to comprehensively consider environmental factors such as air flow and thermal radiation to avoid adverse effects of temperature fluctuations on the forming performance.

[0076] Reasonable standing time and temperature control can not only reduce the risk of molten zinc invading the matrix and causing microcracks, but also reduce the deformation of the sheet caused by temperature difference, improving the forming uniformity and part quality. Examples show that through standing and temperature monitoring, the sheet reaches the best state before entering the mold, providing stable conditions for subsequent stamping and pressure maintaining quenching, thus significantly improving the forming reliability and mechanical properties of the part.

[0077] In some examples, it also includes:

[0078] The cooling roller plays a key role in the pre-cooling process of the zinc-based coated hot forming steel sheet. Its parameters and layout need to be adjusted according to actual production requirements. The main reason for the horizontal layout of the cooling roller is that it is difficult to ensure straightness and is not easy to process during the manufacturing and use of long cooling rollers. By adopting the horizontal arrangement of multiple groups of short cooling rollers, it can not only flexibly cover the width of the sheet, but also improve the machining accuracy and service life of the cooling roller, especially suitable for the hot stamping scenario of multiple parts in one mold. At this time, according to the positions of different sheets, the number and length of the cooling rollers can be flexibly adjusted to ensure uniform cooling of all sheets. It should be noted that the parameters include length, size, rotation speed, and the flow rate and flow of cooling water.

[0079] The longitudinal layout of the cooling roller is mainly used to enhance the cooling effect. When a single group of cooling rollers cannot meet the expected cooling requirements, through the longitudinal multi-group arrangement, the sheet can contact the cooling roller multiple times to achieve more sufficient cooling. The rotation speed or the cooling water flow rate of each longitudinal cooling roller group can be adjusted in stages to adapt to the cooling requirements at different stages. This design not only improves the cooling efficiency, but also ensures the temperature uniformity and stability of the sheet through gradually optimized parameter adjustment.

[0080] Through the comprehensive layout of horizontal and vertical directions, the cooling roller can achieve efficient cooling and meet different production requirements. The horizontal layout ensures flexibility and processability, and the longitudinal layout enhances the cooling capacity and uniformity. The combination of the two significantly reduces the quality defects caused by uneven cooling. Finally, this flexible design improves the forming accuracy and production stability of hot stamping parts, providing an important guarantee for the preparation of high-quality parts.

[0081] In some examples, it also includes:

[0082] In the hot stamping process of zinc-based coated hot-formed steel sheets, pressure holding and quenching is an important link to ensure the performance of parts. After stamping, the parts are rapidly cooled through pressure holding and quenching, causing their microstructure to transform from austenite to high-strength martensite while maintaining the shape accuracy of the parts. The pressure holding pressure is usually set between 300 tons and 1200 tons, and the specific parameters are determined according to the shape, size, and material properties of the parts. For parts with complex shapes or large sizes, a higher pressure holding pressure helps to achieve uniform cooling and reduce defects during the forming process. The pressure holding time is usually 6 to 15 seconds, and it is dynamically adjusted according to the part thickness and die cooling efficiency to ensure that the temperature inside and on the surface drops uniformly.

[0083] The reasonable setting of the pressure holding pressure and time can effectively control the thermal stress and deformation of the parts, improving the forming accuracy and strength. At the same time, the cooling channels in the die further accelerate the cooling process of the parts by flowing through the cooling medium, ensuring the uniformity and efficiency of cooling. For parts with a larger thickness or complex shapes, extending the pressure holding time or increasing the pressure holding pressure can significantly reduce quality defects caused by insufficient cooling or local stress concentration. It should be noted that in this embodiment, the cooling medium can be water cooling or air cooling.

[0084] By optimizing the pressure holding and quenching parameters, hot-stamped parts can achieve excellent mechanical properties and surface quality, while meeting the high-precision requirements of complex parts. Examples show that reasonable pressure holding conditions can not only improve production efficiency but also reduce process defects such as cracks and deformation, ensuring the strength, hardness, and durability of the parts. This process is a key guarantee for the successful manufacturing of complex structural parts such as high-strength automotive components.

[0085] In some examples, it also includes:

[0086] The cooling rolls play a core role in the pre-cooling process of zinc-based coated hot-formed steel. Its design consists of two upper and lower cooling rolls, with cooling water flowing through the inside and equipped with a sealing device to prevent cooling water leakage. This design can ensure the efficient heat dissipation and operating stability of the cooling rolls. The cooling rolls are equipped with a power device and a speed regulation system, and the roll speed is dynamically adjusted through a roll speed optimization model to ensure the uniformity and efficiency of the cooling process. Specifically, when the sheet metal enters the cooling rolls, the two upper and lower circular rolls rotate in cooperation, biting the sheet metal and driving it forward while applying pressure to the sheet metal. To protect the sheet metal from damage, this pressure is strictly controlled below the yield pressure of the sheet metal.

[0087] The rotational speed of the cooling roll is an important factor affecting the cooling uniformity, and its design follows the dynamic relationship between the sheet thickness and speed. When the sheet just enters the cooling roll, the rotational speed is relatively fast to improve the initial cooling efficiency; as the sheet thickness increases and the cooling process progresses, the roll speed gradually decreases, thereby extending the cooling contact time and achieving a more uniform temperature distribution. This dynamic adjustment is completed through a real-time feedback mechanism, which optimizes the roll speed based on the temperature distribution of the sheet after pre-cooling. Through this precise speed control, the cooling roll can effectively balance the cooling efficiency and the sheet quality, avoiding temperature gradients or thermal stresses caused by uneven cooling.

[0088] In summary, the design and operating mechanism of the cooling roll fully embody the balance between efficient cooling and sheet protection. The structure of the upper and lower double rolls combined with the dynamic roll speed adjustment not only improves the cooling uniformity but also can adapt to the requirements of different sheet thicknesses and production rhythms. This efficient and flexible design provides a reliable guarantee for the pre-cooling process of zinc-based coated hot-formed steel and lays the foundation for the subsequent forming quality.

[0089] The technical solution of the present application will be further described in detail through specific embodiments below.

[0090] Comparative Example 1

[0091] A sheet with a thickness of 1.9 mm is heated to 910 °C and held for 5 minutes, then directly transferred to the mold. The maximum temperature of the sheet is 802 °C. During continuous production, after the subsequent sheet is heated and held, it is transferred to the mold, and the maximum temperature of the sheet is 812 °C.

[0092] Example 1

[0093] A sheet with a thickness of 1.9 mm is heated to 910 °C and held for 5 minutes, then removed from the heating furnace and passed through the cooling roll. When the grating and temperature measuring device at the outlet of the heating furnace detect that the sheet has left the furnace, the cooling roll starts to rotate at 200 revolutions per minute. At this time, the average temperatures of the front end and the rear end of the sheet are detected to be 780 °C and 800 °C respectively. Then, the cooling roll stops rotating, and the sheet is transferred to the hot stamping mold. When transferred to the hot stamping mold, the maximum temperature of the sheet is 725 °C. The rotational speed of the cooling roll is calculated based on the temperatures of the front end and the rear end of the sheet after passing through the cooling roll as proposed in this patent. The sheet is divided into the front end and the rear end. The front end corresponds to the first region, and the rear end corresponds to the second region. The front end is the part that enters the cooling roll first, and the rear end is the part that enters last. This division is based on the difference in the contact time between the sheet and the cooling roll during the cooling process of the cooling roll. The cooling roll drives the sheet to move through rotation. The front end stays in the cooling roll for a relatively long time, and the rear end stays for a shorter time. Therefore, the cooling effects of the two parts may be different, which is the reason for the need to design the cooling roll parameters specifically.

[0094] The relationship between the temperature gradient after pre-cooling of the sheet material and the gradient of the roll speed is as follows:

[0095]

[0096] Wherein, T two，n is the average temperature of the second region of the nth sheet material after pre-cooling, and T first，n is the average temperature of the first region of the nth sheet material after pre-cooling, V out，n is the final roll speed when the nth sheet material leaves the cooling roll, and V out，n+1 is the final roll speed when the (n + 1)th sheet material leaves the cooling roll.

[0097] In a feasible implementation manner, it further includes:

[0098] The initial roll speed V in，n of the nth sheet material is a preset initial value;

[0099] In the case of n = 1, the final roll speed V out，1 of the first sheet material is a preset final value;

[0100] In the case of n > 1, the final roll speed V out，n of the nth sheet material is determined based on the final roll speed V out，n-1 of the previous sheet material, wherein the final roll speed of the above cooling roll shows a downward trend as the number of sheet materials increases.

[0101] In this embodiment, the average temperature T two，1 of the second region of the first sheet material = 800, the average temperature T first，1 of the first region of the first sheet material = 780, and the initial roll speed T in，1 of the first sheet material is a preset initial value, wherein the preset initial value is 200. When pre-cooling the first sheet material, the rotation speed of the cooling roll does not change. To further improve the uniformity of pre-cooling, calculate the value of V out，n+1 according to the temperature and rotation speed after pre-cooling of the first sheet material. After calculation, the final roll speed V out，n+1 of the second sheet material is 195 revolutions per minute.

[0102] When the second sheet is heated and enters the cooling roller, the roller speed starts to decrease from the preset initial value of 200 revolutions per minute. When the sheet leaves the cooling roller, the rotational speed is 195 revolutions per minute. After the sheet leaves the cooling roller, the temperature of the sheet is detected. The average temperature of the front end is 775 °C, and the average temperature of the rear end is 780 °C. When the sheet is transferred to the hot stamping die, the maximum temperature of the sheet is 716 °C. Based on the temperatures of the first and second regions of the second sheet and the final roller speed, the final roller speed of the third sheet is calculated, and the final roller speed of the third sheet is 193.75 revolutions per minute. That is to say, the third sheet starts at 200 revolutions per minute and leaves at 193.75 revolutions per minute, and so on.

[0103] In the cooling process of zinc-based coated hot-formed steel, dynamic cooling is carried out through the cooling roller, and the sheet is divided into the front end and the rear end, effectively optimizing the uniformity and efficiency of the cooling process. The cooling roller dynamically adjusts the rotational speed according to the temperature distribution of different regions of the sheet to ensure uniform cooling effect of the sheet from entering to leaving the cooling roller. Especially in the case of continuous processing of multiple sheets, this zoning design and dynamic regulation can fully address the problem of uneven cooling caused by the difference in the contact time of the front and rear ends of the sheet with the cooling roller, providing highly precise control for the entire cooling process. It should be noted that in this embodiment, the front end is the first region and the rear end is the second region.

[0104] Specific embodiments show that in the cooling process of the first sheet, the initial rotational speed of the cooling roller is the preset 200 revolutions per minute and remains the same when leaving; while in the case of the second sheet, the final roller speed is adjusted to 195 revolutions per minute according to the temperature distribution of the previous sheet, and the difference in temperature between the front and rear ends when leaving is reduced to only 5 °C. This design significantly improves the cooling uniformity and avoids thermal stress and quality defects caused by excessive temperature gradient during the cooling process of the sheet. The third sheet continues to enter the cooling roller at an initial rotational speed of 200 revolutions per minute, and the final roller speed is further optimized to 193.75 revolutions per minute. This decreasing roller speed design not only meets the actual cooling requirements but also effectively reduces energy consumption.

[0105] Compared with the comparative method without using a cooling roll, the addition of the cooling roll reduced the maximum temperature of the sheet metal from 802 °C to 725 °C and further controlled it to 716 °C, creating stable temperature conditions for subsequent hot stamping and forming operations. This process design not only improves the cooling efficiency but also significantly reduces problems such as cracks and deformations caused by uneven cooling. The dynamic adjustment technology of the cooling roll combined with the method of area division ensures the accuracy of cooling and provides a strong guarantee for the part quality in large-scale continuous production. The remarkable effect of this process method lies in the precise management of the temperature distribution difference during the cooling process through the dynamic adjustment of the cooling roll and temperature feedback control. Whether in the processing of a single sheet metal or multiple continuous sheet metals, this method can effectively reduce process defects caused by insufficient cooling or overcooling and improve the stability of part quality. At the same time, the cooling uniformity is optimized through the design of decreasing roll speed, providing an advanced solution for the manufacturing of high-strength and corrosion-resistant parts in industrial production.

[0106] Please refer to Figure 2 , which is a schematic structural diagram of a processing control device for a hot-formed steel part provided by an embodiment of the present application, including:

[0107] A temperature detection unit 21 for detecting the temperature of different regions of a zinc-based coated hot-formed steel sheet to determine the average temperature of each region. Among them, the above-mentioned zinc-based coated hot-formed steel sheet includes a first region and a second region, the above-mentioned first region and the above-mentioned second region do not overlap, and the time when the first region enters the cooling roll is earlier than the time when the second region enters the above-mentioned cooling roll;

[0108] A sheet cooling unit 22 for pre-cooling the above-mentioned different regions based on the average temperature of each region and a cooling roll parameter control model to obtain a steel sheet to be stamped. Among them, the cooling roll parameters corresponding to the cooling roll parameter control model include cooling roll speed, cooling roll temperature, and cooling water flow rate;

[0109] A part forming unit 23 for stamping and forming and pressure maintaining and quenching the above-mentioned steel sheet to be stamped to obtain a zinc-based coated hot-formed steel part.

[0110] Please refer to Figure 3 , an embodiment of the present application also provides an electronic device 300, including a memory 310, a processor 320, and a computer program 311 stored on the memory 310 and executable on the processor. When the processor 320 executes the computer program 311, it implements the steps of any of the above methods for processing control of a hot-formed steel part.

[0111] Since the electronic device introduced in this embodiment is the device used in a processing control device for a hot-formed steel part in an embodiment of the present application, based on the method introduced in the embodiment of the present application, those skilled in the art can understand the specific implementation manners of the electronic device in this embodiment and its various forms of variation. Therefore, the specific implementation of how this electronic device implements the method in the embodiment of the present application will not be described in detail here. As long as the device used by those skilled in the art to implement the method in the embodiment of the present application belongs to the scope protected by the present application.

[0112] In the specific implementation process, when the computer program 311 is executed by the processor, it can implement any implementation manner in the corresponding embodiment of the first aspect.

[0113] It should be noted that in the above embodiments, the descriptions of each embodiment have their own emphases. For the parts not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0114] Those skilled in the art should understand that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can take the form of a computer program product implemented on one or more computer-readable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-readable program code.

[0115] The present application is described with reference to the flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or block in the flowcharts and / or block diagrams, and the combination of processes and / or blocks in the flowcharts and / or block diagrams can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded computer, or other programmable data processing devices to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing devices generate a device for implementing the specified function in Figure 1 one process or multiple processes and / or blocks Figure 1 one block or multiple blocks.

[0116] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer-readable memory generate a manufactured article including an instruction device, and the instruction device implements the specified function in Figure 1 one process or multiple processes and / or blocks Figure 1 one block or multiple blocks.

[0117] These computer program instructions can also be loaded onto a computer or other programmable data processing apparatus, causing a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, so that the instructions executed on the computer or other programmable apparatus provide steps for implementing the functions specified in one process Figure 1 one process or multiple processes and / or blocks Figure 1 steps of the functions specified in one block or multiple blocks.

[0118] The embodiments of the present application also provide a computer program product, which includes computer software instructions. When the computer software instructions run on a processing device, the processing device is caused to execute Figure 1 the process corresponding to a processing control method of a hot forming steel part in the corresponding embodiment.

[0119] The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the processes or functions according to the embodiments of the present application are wholly or partially generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from a website, a computer, a server, or a data center to another website, a computer, a server, or a data center in a wired manner (such as coaxial cable, optical fiber, digital subscriber line (DSL)) or a wireless manner (such as infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that can be stored by a computer or a data storage device such as a server or a data center that includes one or more integrated available media. The available medium can be a magnetic medium (for example, a floppy disk, a hard disk, a magnetic tape), an optical medium (for example, a DVD), or a semiconductor medium (for example, a solid state disk (SSD)), etc.

[0120] Those skilled in the art can clearly understand that for the convenience and brevity of description, the specific working processes of the above-described systems, apparatuses, and units can refer to the corresponding processes in the foregoing method embodiments and will not be described herein again.

[0121] In several embodiments provided by the present application, it should be understood that the disclosed devices, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative. For example, the division of units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed coupling, direct coupling, or communication connection between each other can be through some interfaces, and the indirect coupling or communication connection of devices or units can be in electrical, mechanical, or other forms.

[0122] The units described as separate components may or may not be physically separated. The components displayed as units may or may not be physical units, that is, they can be located in one place or distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0123] In addition, each functional unit in various embodiments of the present application can be integrated in a processing unit, or each unit can exist physically alone, or two or more units can be integrated in one unit. The above-mentioned integrated units can be implemented in the form of hardware or in the form of software functional units.

[0124] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art, or all or part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods in various embodiments of the present application. The aforementioned storage medium includes: USB flash drives, mobile hard disks, read-only memories (ROM), random access memories (RAM), magnetic disks, or optical discs, and other various media that can store program codes.

[0125] The above embodiments are only used to illustrate the technical solution of the present application and are not intended to limit it. Although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments or perform equivalent replacements for some of the technical features. And these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of various embodiments of the present application.

[0126] Although the preferred embodiments of this specification have been described, additional changes and modifications can be made by those skilled in the art once they learn of the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications that fall within the scope of this specification.

[0127] Obviously, those skilled in the art can make various changes and deformations to this specification without departing from the spirit and scope of this specification. Thus, if these modifications and variations of this specification fall within the scope of the claims of this specification and their equivalent technologies, this specification is also intended to include these modifications and variations.

Claims

1. A processing control method for hot-formed steel parts, characterized in that: The method comprises: Performing temperature detection on different regions of the zinc-based hot-formed steel sheet material to determine the average temperature of each region, wherein the zinc-based hot-formed steel sheet material includes a first region and a second region, the first region and the second region do not overlap, and the first region enters the cooling roller earlier than the second region enters the cooling roller; Based on the average temperature of each area and the cooling roller parameter control model, the different areas are pre-cooled to obtain the steel plate to be stamped, wherein the cooling roller parameters corresponding to the cooling roller parameter control model include the cooling roller speed, the cooling roller temperature and the cooling water flow rate; The steel plate to be stamped is subjected to stamping forming and pressure-maintaining quenching to obtain a zinc-based coated hot-formed steel part.

2. The processing control method of hot-formed steel parts according to claim 1, characterized in that: The cooling roller speed is determined based on the following formula: Among them, T two，n is the average temperature of the nth sheet in the second region after precooling, T first，n is the average temperature of the nth sheet in the first region after precooling, V out，n V is the final roller speed when the nth sheet leaves the cooling roller, out，n+1 It is the final roller speed when the n+1th sheet leaves the cooling roller.

3. The processing control method of hot-formed steel parts according to claim 2, characterized in that: Initial roller speed V of the nth sheet in，n is the preset initial value; In the case of n = 1, the ending roller speed V of the first sheet out，1 is the preset termination value; When n>1, the ending roller speed V of the nth sheet out，n Based on the final roller speed V of the previous sheet out，n-1 It is determined that the terminal roller speed of the cooling roller shows a downward trend as the number of sheets increases.

4. The processing control method of hot-formed steel parts according to claim 1, characterized in that: The cooling water flow rate is determined based on the following formula: Where Q is the cooling water flow rate, H is the heat transfer, ρ is the cooling water density, C is the cooling water specific heat capacity, ΔT w is the cooling water inlet and outlet temperature difference; The cooling roller temperature is determined based on the following formula: Among them, T b is the cooling roller temperature, T i is the initial temperature of the cooling roller, Δx is the thickness of the cooling roller, k is the thermal conductivity, and A is the heat conduction area.

5. The processing control method of hot-formed steel parts according to claim 1, characterized in that: Before the temperature detection of different areas of the zinc-based coated hot-formed steel sheet is performed, the method includes: The zinc-based coated hot-formed steel sheet is subjected to an austenitizing heat treatment, wherein the austenitizing heat treatment includes roller hearth furnace heating, box-type heating furnace heating, induction heating and resistance heating.

6. The processing control method of hot-formed steel parts according to claim 1, characterized in that: The temperature difference between the pre-cooled plate and the pre-cooled plate is within a first preset range, wherein the first preset range is greater than or equal to the first preset temperature and less than or equal to the second preset temperature.

7. The processing control method of hot-formed steel parts according to claim 1, characterized in that: Also includes: After the pre-cooling operation is completed and before the stamping operation, the sheet metal is controlled to stand still for a first preset time so that the temperature of the sheet metal is lower than the preset stamping temperature.

8. A processing control device for hot-formed steel parts, characterized in that: include: A temperature detection unit is used to detect the temperature of different areas of the zinc-based hot-formed steel sheet material to determine the average temperature of each area, wherein the zinc-based hot-formed steel sheet material includes a first area and a second area, the first area and the second area do not overlap, and the first area enters the cooling roller earlier than the second area enters the cooling roller; A sheet cooling unit, used for pre-cooling the different regions based on the average temperature of each region and a cooling roller parameter control model to obtain a steel plate to be stamped, wherein the cooling roller parameters corresponding to the cooling roller parameter control model include cooling roller speed, cooling roller temperature and cooling water flow rate; The part forming unit is used for performing stamping forming and pressure-holding quenching on the steel plate to be stamped to obtain a zinc-based coated hot-formed steel part.

9. An electronic device, comprising: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor is used to implement the steps of the processing control method for a hot-formed steel part as described in any one of claims 1 to 7 when executing the computer program stored in the memory.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the processing control method of the hot-formed steel part according to any one of claims 1 to 7 is implemented.

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