A method for controlling the temperature of a die-casting die for casting metal

Abstract

The application discloses a die-casting die temperature control method for metal casting, relates to the field of metal processing, and solves the problem of low die-casting success rate. The method comprises the following steps: obtaining a material type corresponding to pre-input die-casting raw materials and a raw material weight, calculating estimated melting heat of the die-casting raw materials according to the material type and the raw material weight, setting a melting temperature and a melting time length of the die-casting raw materials according to the estimated melting heat, melting and refining based on the melting temperature and the melting time length, obtaining slag-removed molten die-casting raw materials, spraying a release agent to an inner surface of a die-casting cavity, then injecting the slag-removed molten die-casting raw materials into the die-casting cavity, and monitoring the die-casting cavity in real time, correcting and regulating the temperature of the die-casting cavity according to positive and negative temperature abnormal deviation values of a plurality of temperature monitoring sub-regions of the die-casting cavity, taking out die-casting devices in the die-casting cavity after the die-casting cavity is cooled, and improving the die-casting success rate.

Description

Technical Field

[0001] This invention belongs to the field of metal processing technology, specifically a method for temperature control of die-casting molds for metal casting. Background Technology

[0002] Die casting is a metal casting process characterized by applying high pressure to molten metal within a mold cavity. The mold is typically made of a high-strength alloy, and the process is somewhat similar to injection molding. Most die-cast parts are iron-free, containing materials such as zinc, copper, aluminum, magnesium, lead, tin, and lead-tin alloys and their alloys. Die casting molds are tools used to cast metal parts on specialized die-casting and forging machines. Depending on the type of die casting, either a cold chamber die-casting machine or a hot chamber die-casting machine is required. Proper temperature control ensures the fluidity of the molten metal and reduces internal defects in the casting, such as shrinkage cavities and porosity.

[0003] However, at present, when controlling the temperature of die casting molds, temperature monitoring is usually only carried out in the final die casting stage, resulting in low purity of the die-cast parts after molding. At the same time, the existing monitoring methods usually select a few temperature monitoring points, which may result in the omission of temperature anomalies, leading to a decrease in the success rate of die casting.

[0004] Therefore, this invention proposes a method for temperature control of die-casting molds for metal casting. Summary of the Invention

[0005] The purpose of this invention is to provide a method for temperature control of die-casting molds for metal casting, so as to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A method for temperature control of die-casting molds for metal casting, the method comprising:

[0008] Step S1: Obtain the material type and weight of the pre-input die casting raw material, and calculate the estimated melting heat of the die casting raw material based on the material type and quantity.

[0009] Step S2: Set the melting temperature and melting time of the die casting raw material according to the estimated melting heat, and perform melting and refining based on the melting temperature and melting time to obtain slag-removed melted die casting raw material;

[0010] Step S3: Spray a release agent onto the inner surface of the die casting cavity, and then inject the slag-removed molten die casting raw material into the die casting cavity, and monitor the die casting cavity in real time.

[0011] Step S4: Adjust the temperature of the die-casting cavity based on the positive and negative temperature anomaly deviation values ​​of multiple temperature monitoring sub-regions of the die-casting cavity.

[0012] Step S5: After the die-casting cavity has cooled down, remove the die-casting components from inside the die-casting cavity.

[0013] Furthermore, the calculation process for the estimated heat of fusion is as follows:

[0014] Step S11: Identify the melting point temperature (WD) of the die-casting raw material based on its material type. 原 Compared with the specific heat capacity of raw materials C 原 ;

[0015] Step S12, read the temperature of the die-casting mold at the initial moment and record it as WD. 压 ;

[0016] Step S13: Calculate the estimated melting heat YR of the die-casting raw material using the formula. 原 The formula is as follows:

[0017] YR 原 =ZL 原 ×C 原 ×(WD 原 -WD 压 )+QR 原 Among them, ZL 原 For raw material weight, QR 原 This refers to the latent heat of the die-casting raw materials.

[0018] Further, step S2 includes the following sub-steps:

[0019] Step S21: Scan the image of the outer surface of the die-casting raw material and automatically calculate the total area MJ of the outer surface of the die-casting raw material based on the modeling software.

[0020] Step S22: Record the distance from the geometric center of the die-casting raw material to any point on the outer surface as the calibration distance, and select the longest calibration distance as the maximum heating distance JL of the die-casting raw material;

[0021] Step S23: Calculate the heat flow rate RLL of the die-casting raw material using Fourier's law of heat conduction. The specific calculation formula is as follows:

[0022] In the formula, K is the thermal conductivity of the die-casting raw material, and the negative sign before the thermal conductivity indicates that the heat transfer direction is opposite to the temperature gradient direction.

[0023] Step S24: The estimated heating time is obtained by dividing the estimated melting heat of the die-casting raw material by the heat flow rate of the die-casting raw material.

[0024] Furthermore, step S2 also includes the following sub-steps:

[0025] Step S25: Place the die casting raw material in a metal melting chamber, record the melting point temperature of the raw material as the melting temperature, record the estimated heating time as the melting time, and process the die casting raw material based on the melting temperature and melting time to obtain molten die casting raw material.

[0026] Step S26: Add a refining agent to the molten die casting raw material to adsorb oxide impurities in the molten die casting raw material through a chemical reaction and precipitate raw material residue.

[0027] Step S27: Add a covering agent to the molten die casting raw material, let it stand for a fixed time, remove the slag on the surface of the molten die casting raw material with a skimming tool, and repeat the operation until constant weight is achieved;

[0028] Step S28: Place the slag-removed molten die-casting raw material back into the metal melting chamber and heat until it is completely melted to obtain slag-removed molten die-casting raw material.

[0029] Further, step S3 includes the following sub-steps:

[0030] Step S31: Obtain the volume TJ corresponding to the die-casting cavity. 腔 The volume of the overflow tank (TJ) 流 And the volume of the exhaust channel TJ 气 ;

[0031] Step S32: Calculate the calculated injection volume TJ of the die-casting cavity using the formula. 注 The formula is as follows:

[0032] TJ 注 =(TJ 腔 +TJ 流 +TJ 气 )×(1+α)×(1+β;where α is the shrinkage rate compensation coefficient and β is the process loss coefficient;

[0033] Step S33: Calculate the calculated injection weight ZL of the die-casting cavity using the formula. 注 The formula is as follows:

[0034] ZL 注 =ρ 熔 ×TJ 注 In the formula, ρ 熔 This refers to the density of the die-casting raw material in its molten state.

[0035] Furthermore, step S3 also includes the following sub-steps:

[0036] Step S34: Inject the slag-removed molten die-casting raw material (calculated injection weight) into the pressure chamber, and increase the pressure in the pressure chamber to negative pressure (≤10 mbar) to cause the gas in the pressure chamber to escape; connect the vacuum pump to the exhaust tank, and reduce the pressure in the die-casting cavity to 10 mbar through the vacuum pump, and then connect the pressure chamber to the die-casting cavity.

[0037] Step S35: Increase the pressure in the pressure chamber. Under high pressure, the slag-removing and molten die-casting raw materials are injected into the die-casting cavity through multiple inner gates.

[0038] Step S36: Calculate the working die-casting temperature of the die-casting cavity;

[0039] Step S37: The die-casting cavity is used for die-casting at the working die-casting temperature, and the abnormal temperature deviation value of the die-casting cavity is monitored.

[0040] Furthermore, the calculation process for the working die-casting temperature is as follows:

[0041] Step S361: Collect historical die casting data that is the same as the material type corresponding to the die casting raw material; wherein, the historical die casting data includes the historical die casting temperature and the total number of die castings and the number of die casting failures corresponding to the historical die casting temperature;

[0042] Step S362: Die casting success rate corresponding to different historical die casting temperatures is obtained by dividing the difference between the total number of die castings and the number of die casting failures by the total number of die castings; the historical die casting temperatures are arranged in descending order of die casting success rate.

[0043] Step S363: Select the top three historical die-casting temperatures, sum them up, and take the average value as the working die-casting temperature of the die-casting cavity.

[0044] Furthermore, the monitoring process for the abnormal temperature deviation value is as follows:

[0045] Step S371: Read the infrared image of the die-casting cavity during the die-casting operation using an infrared sensing device; set multiple temperature monitoring points at fixed intervals in the infrared image of the die-casting cavity, with each temperature monitoring point numbered n and n having an upper limit value of x.

[0046] Step S372: Using the temperature monitoring point as the center and half of the multiple dividing intervals as the side length, divide the infrared image into multiple temperature monitoring sub-regions. The number of each temperature monitoring sub-region is the same as the number of the corresponding temperature monitoring point.

[0047] Step S373: For any temperature monitoring sub-region, read the pixel values ​​of all pixels in the temperature sub-region, and divide the pixel value of each pixel into R value component Ri, G value component Gi and B value component Bi; where i is the pixel number, i=1,2,...,z, and z is the upper limit of the number;

[0048] Step S374: Calculate the pixel comparison value XBi for each pixel using the following formula:

[0049] XBi=Ri×A1+Gi×A2+Bi×A3; where A1, A2 and A3 are weighting coefficients, and A2>A1>A3.

[0050] Furthermore, the monitoring process for the abnormal temperature deviation value also includes:

[0051] Step S375: Sum the pixel comparison values ​​of all pixels in the same temperature monitoring sub-region to obtain the pixel comparison mean; then calculate the pixel comparison standard deviation of the same temperature monitoring sub-region.

[0052] Step S376: Subtract the standard deviation of pixel comparison from the mean of pixel comparison as the left endpoint of the interval, and add the standard deviation of pixel comparison to the mean of pixel comparison as the right endpoint of the interval; construct the filtering interval based on the left and right endpoints of the interval.

[0053] Iterate through the pixel comparison values ​​of all pixels and compare each pixel comparison value with the selected range;

[0054] If the pixel comparison value of a pixel is less than the left endpoint of the interval or greater than the right endpoint of the interval, that is, the pixel comparison value is outside the filtering interval, then the corresponding pixel is recorded as an abnormal temperature pixel.

[0055] If the pixel comparison value of a pixel is greater than or equal to the left endpoint of the interval or less than or equal to the right endpoint of the interval, that is, the pixel comparison value is within the filtering interval, then no operation is performed;

[0056] Step S377: Record the pixel comparison values ​​of all abnormal temperature pixels. Subtract the average pixel comparison value from the pixel comparison value to obtain the comparison deviation value of the corresponding abnormal temperature pixel. Sum all comparison deviation values ​​greater than zero in the same temperature monitoring sub-region to obtain the positive temperature abnormality deviation value of the corresponding temperature monitoring sub-region. Sum all comparison deviation values ​​less than zero in the same temperature monitoring sub-region to obtain the negative temperature abnormality deviation value of the corresponding temperature monitoring sub-region.

[0057] Step S378: Calculate the positive and negative temperature anomaly deviation values ​​for all temperature sub-regions.

[0058] Further, step S4 includes the following sub-steps:

[0059] Step S41: Obtain the positive and negative temperature anomaly deviation values ​​for the temperature monitoring sub-region;

[0060] Step S42: Perform cooling correction control on the abnormal temperature pixel corresponding to the positive temperature abnormal deviation value in the temperature monitoring sub-region, that is, reduce the real-time temperature of the abnormal temperature pixel to the working die-casting temperature.

[0061] Step S43: Perform temperature rise correction control on the abnormal temperature pixel corresponding to the negative temperature abnormal deviation value in the temperature monitoring sub-region, that is, raise the real-time temperature of the abnormal temperature pixel to the working die casting temperature.

[0062] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0063] 1. This invention first obtains the material type and weight of the pre-input die-casting raw material, and calculates the estimated melting heat of the die-casting raw material based on the material type and quantity; then, based on the estimated melting heat, sets the melting temperature and melting time of the die-casting raw material, and performs melting and refining based on the melting temperature and melting time to obtain slag-removed melted die-casting raw material; this invention realizes the melting and refining of die-casting raw materials.

[0064] 2. In this invention, a release agent is sprayed onto the inner surface of the die-casting cavity, and then slag-removed molten die-casting raw materials are injected into the die-casting cavity. The die-casting cavity is monitored in real time, and the temperature of the die-casting cavity is adjusted based on the positive and negative temperature anomaly deviation values ​​of multiple temperature monitoring sub-regions of the die-casting cavity. After the die-casting cavity cools down, the die-casting device inside the die-casting cavity is removed. This invention improves the forming probability of die-casting devices by controlling the temperature of the die-casting mold. Attached Figure Description

[0065] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to the accompanying drawings.

[0066] Figure 1 This is a flowchart illustrating the overall method of the present invention;

[0067] Figure 2 This is a structural block diagram of the die-casting mold in this invention;

[0068] Figure 3 A schematic diagram of the structure of a computer device designed for invention. Detailed Implementation

[0069] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0070] Example 1, please refer to Figure 1 and Figure 2 As shown, the technical solution provided by the present invention is: a method for temperature control of die casting mold for metal casting. The method analyzes the state of the raw materials corresponding to the die casting device under different die casting processes, and adjusts the temperature of different areas of the die casting mold according to the state of the raw materials, so as to achieve precise temperature control of the die casting mold during operation and ensure the molding of the die casting device.

[0071] like Figure 2 As shown, the die-casting mold includes a metal melting chamber, a pressure chamber, and a die-casting cavity; wherein the metal melting chamber is used to convert the die-casting raw materials into a liquid molten state, the pressure chamber is used to adjust the pressure, and the die-casting cavity is used to perform the actual die-casting operation;

[0072] In this embodiment, the method for controlling the temperature of the die-casting mold is as follows:

[0073] Step S1: Obtain the material type and weight of the pre-input die casting raw material, and calculate the estimated melting heat of the die casting raw material based on the material type and quantity.

[0074] In this invention, step S1 includes the following sub-steps:

[0075] Step S11: Identify the melting point temperature (WD) of the die-casting raw material based on its material type. 原 Compared with the specific heat capacity of raw materials C 原 ;

[0076] Step S12, read the temperature of the die-casting mold at the initial moment and record it as WD. 压 ;

[0077] Step S13: Calculate the estimated melting heat YR of the die-casting raw material using the formula. 原 The formula is as follows:

[0078] YR 原 =ZL 原 ×C 原 ×(WD 原 -WD 压 )+QR 原 Among them, ZL 原 For raw material weight, QR 原The latent heat of die-casting raw materials refers to the heat absorbed or released by a substance when it changes from one phase to another under isothermal and isobaric conditions. The specific calculation formula is as follows: Latent heat of die-casting raw materials = weight of raw materials × specific latent heat value of die-casting raw materials.

[0079] Step S2: Set the melting temperature and melting time of the die casting raw material according to the estimated melting heat, and perform melting and refining based on the melting temperature and melting time to obtain slag-removed melted die casting raw material;

[0080] In this invention, step S2 includes the following sub-steps;

[0081] Step S21: Scan the image of the outer surface of the die-casting raw material and automatically calculate the total area MJ of the outer surface of the die-casting raw material based on modeling software (such as SolidWorks or AutoCAD).

[0082] Step S22: Record the distance from the geometric center of the die-casting raw material to any point on the outer surface as the calibration distance, and select the longest calibration distance as the maximum heating distance JL of the die-casting raw material;

[0083] Step S23: Calculate the heat flow rate RLL of the die-casting raw material using Fourier's law of heat conduction. The specific calculation formula is as follows:

[0084] In the formula, K is the thermal conductivity of the die-casting raw material. It should be noted that the negative sign before the thermal conductivity indicates that the heat transfer direction is opposite to the temperature gradient direction.

[0085] Step S24: The estimated heating time is obtained by dividing the estimated melting heat of the die-casting raw material by the heat flow rate of the die-casting raw material.

[0086] Step S25: Place the die casting raw material in a metal melting chamber, record the melting point temperature of the raw material as the melting temperature, record the estimated heating time as the melting time, and process the die casting raw material based on the melting temperature and melting time to obtain molten die casting raw material.

[0087] Step S26: Add a refining agent to the molten die-casting raw material to adsorb oxide impurities in the molten die-casting raw material through a chemical reaction and precipitate raw material residue; wherein, the refining agent is a chloride, preferably a 1:1 mixture of sodium chloride and potassium chloride;

[0088] Step S27: Add a covering agent to the molten die-casting raw material, let it stand for a fixed time, remove the slag from the surface of the molten die-casting raw material using a skimming tool, and repeat the operation until a constant weight is achieved. In actual operation, the fixed standing time is selected according to the material type of the die-casting raw material. For example, if the die-casting raw material is aluminum liquid or magnesium alloy, the fixed time is ten to fifteen minutes; if the die-casting raw material is steel liquid, the fixed time is five to ten minutes.

[0089] The covering agent is a fluoride salt, the purpose of which is to prevent oxidation of the molten die-casting raw material; for example, if the molten die-casting raw material is aluminum, then the covering agent is sodium hexafluoroaluminate.

[0090] Step S28: Place the slag-removed molten die-casting raw material back into the metal melting chamber and heat until it is completely melted to obtain slag-removed molten die-casting raw material.

[0091] Step S3: Spray a release agent onto the inner surface of the die casting cavity, and then inject the slag-removed molten die casting raw material into the die casting cavity, and monitor the die casting cavity in real time.

[0092] The main function of the release agent is to form a lubricating film on the surface of the die-casting cavity, thereby reducing the adhesion between the die-casting cavity and the die-casting product, so that the die-casting product can be released from the die-casting cavity more smoothly.

[0093] In this invention, step S3 includes the following sub-steps:

[0094] Step S31: Obtain the volume TJ corresponding to the die-casting cavity. 腔 The volume of the overflow tank (TJ) 流 And the volume of the exhaust channel TJ 气 ;

[0095] It should be noted that if the volume of the overflow channel or the venting channel cannot be determined, the volume of the overflow channel shall be considered as 5% to 10% of the corresponding volume of the die-casting cavity, and the volume of the venting channel shall be considered as 0.5% to 2% of the corresponding volume of the die-casting cavity.

[0096] Step S32: Calculate the calculated injection volume TJ of the die-casting cavity using the formula. 注 The formula is as follows:

[0097] TJ 注 =(TJ 腔 +TJ 流 +TJ 气 )×(1+α)×(1+β;where α is the shrinkage compensation coefficient and β is the process loss coefficient;

[0098] When molten metal cools and solidifies, its volume shrinks, therefore compensation must be made according to the material's shrinkage rate. For example, the shrinkage rate compensation coefficient for aluminum alloys is 0.5% to 0.7%, for zinc alloys it is 0.7% to 0.1.2%, and for magnesium alloys it is 1.0% to 1.5%. The process loss coefficient is determined by factors such as the type of raw material, processing technology, processing equipment, and operating techniques, and is generally taken as 3% to 5%.

[0099] Step S33: Calculate the calculated injection weight ZL of the die-casting cavity using the formula.注 The formula is as follows:

[0100] ZL 注 =ρ 熔 ×TJ 注 In the formula, ρ 熔 This refers to the density of the die-casting raw material in its molten state.

[0101] Step S34: Inject the slag-removed molten die-casting raw material (calculated injection weight) into the pressure chamber, and increase the pressure in the pressure chamber to negative pressure (≤10 mbar) to cause the gas in the pressure chamber to escape; connect the vacuum pump to the exhaust tank, and reduce the pressure in the die-casting cavity to 10 mbar through the vacuum pump, and then connect the pressure chamber to the die-casting cavity.

[0102] Step S35: Increase the pressure in the pressure chamber. Under high pressure, the slag-removing and molten die-casting raw materials are injected into the die-casting cavity through multiple inner gates.

[0103] Step S36: Calculate the working die-casting temperature of the die-casting cavity;

[0104] Specifically, the calculation process for the working die-casting temperature in step S36 is as follows:

[0105] Step S361: Collect historical die casting data that is the same as the material type corresponding to the die casting raw material; wherein, the historical die casting data includes the historical die casting temperature and the total number of die castings and the number of die casting failures corresponding to the historical die casting temperature;

[0106] Step S362: Die casting success rate corresponding to different historical die casting temperatures is obtained by dividing the difference between the total number of die castings and the number of die casting failures by the total number of die castings; the historical die casting temperatures are arranged in descending order of die casting success rate.

[0107] Step S363: Select the top three historical die-casting temperatures, sum them up, and take the average value as the working die-casting temperature of the die-casting cavity;

[0108] Step S37: The die-casting cavity is used for die-casting at the working die-casting temperature, and the abnormal temperature deviation value of the die-casting cavity is monitored.

[0109] In this invention, the monitoring process in step S37 is specifically as follows:

[0110] Step S371: Read the infrared image of the die-casting cavity during the die-casting operation using an infrared sensing device; set multiple temperature monitoring points at fixed intervals in the infrared image of the die-casting cavity, with each temperature monitoring point numbered n and n having an upper limit value of x.

[0111] Step S372: Using the temperature monitoring point as the center and half of the multiple dividing intervals as the side length, divide the infrared image into multiple temperature monitoring sub-regions. The number of each temperature monitoring sub-region is the same as the number of the corresponding temperature monitoring point.

[0112] Step S373: For any temperature monitoring sub-region, read the pixel values ​​of all pixels in the temperature sub-region, and divide the pixel value of each pixel into R value component Ri, G value component Gi and B value component Bi; where i is the pixel number, i=1,2,...,z, and z is the upper limit of the number;

[0113] Step S374: Calculate the pixel comparison value XBi for each pixel using the following formula:

[0114] XBi=Ri×A1+Gi×A2+Bi×A3; where A1, A2 and A3 are weighting coefficients, where A2>A1>A3. In specific calculations, A1=0.299, A2=0.587 and A3=0.114 can be selected.

[0115] Step S375: Sum the pixel comparison values ​​of all pixels in the same temperature monitoring sub-region to obtain the pixel comparison mean; then calculate the pixel comparison standard deviation of the same temperature monitoring sub-region.

[0116] Step S376: Subtract the standard deviation of pixel comparison from the mean of pixel comparison as the left endpoint of the interval, and add the standard deviation of pixel comparison to the mean of pixel comparison as the right endpoint of the interval; construct the filtering interval based on the left and right endpoints of the interval.

[0117] Iterate through the pixel comparison values ​​of all pixels and compare each pixel comparison value with the selected range;

[0118] If the pixel comparison value of a pixel is less than the left endpoint of the interval or greater than the right endpoint of the interval, that is, the pixel comparison value is outside the filtering interval, then the corresponding pixel is recorded as an abnormal temperature pixel.

[0119] If the pixel comparison value of a pixel is greater than or equal to the left endpoint of the interval or less than or equal to the right endpoint of the interval, that is, the pixel comparison value is within the filtering interval, then no operation is performed;

[0120] Step S377: Record the pixel comparison values ​​of all abnormal temperature pixels. Subtract the average pixel comparison value from the pixel comparison value to obtain the comparison deviation value of the corresponding abnormal temperature pixel. Sum all comparison deviation values ​​greater than zero in the same temperature monitoring sub-region to obtain the positive temperature abnormality deviation value of the corresponding temperature monitoring sub-region. Sum all comparison deviation values ​​less than zero in the same temperature monitoring sub-region to obtain the negative temperature abnormality deviation value of the corresponding temperature monitoring sub-region.

[0121] Step S378: Calculate the positive and negative temperature anomaly deviation values ​​for all temperature sub-regions.

[0122] Step S4: Adjust the temperature of the die-casting cavity based on the positive and negative temperature anomaly deviation values ​​of multiple temperature monitoring sub-regions of the die-casting cavity.

[0123] In this invention, step S4 includes the following sub-steps:

[0124] Step S41: Obtain the positive and negative temperature anomaly deviation values ​​for the temperature monitoring sub-region;

[0125] Step S42: Perform cooling correction control on the abnormal temperature pixel corresponding to the positive temperature abnormal deviation value in the temperature monitoring sub-region, that is, reduce the real-time temperature of the abnormal temperature pixel to the working die-casting temperature.

[0126] Step S43: Perform temperature rise correction control on the abnormal temperature pixel corresponding to the negative temperature abnormal deviation value in the temperature monitoring sub-region, that is, raise the real-time temperature of the abnormal temperature pixel to the working die casting temperature.

[0127] Cooling correction control is achieved through a water temperature controller and a spot chiller; heating correction control is achieved through an oil temperature controller.

[0128] Step S5: After the die-casting cavity has cooled down, remove the die-casting components from inside the die-casting cavity.

[0129] In this application, if a corresponding calculation formula appears, the above calculation formula is a dimensionless calculation. The weighting coefficient, proportional coefficient and other coefficients in the formula are set to quantify each parameter to obtain a result value. The size of the weighting coefficient and proportional coefficient is only required to not affect the proportional relationship between the parameter and the result value.

[0130] Example 2, as Figure 3As shown, this embodiment provides a computer device, which may include a processor, a communication interface, a memory, and a communication bus. The processor, communication interface, and memory communicate with each other via the communication bus. The processor can call logical instructions in the memory to execute a method for controlling the temperature of a die-casting mold for metal casting. This method includes: acquiring the material type and weight of a pre-input die-casting raw material; calculating the estimated melting heat of the die-casting raw material based on the material type and quantity; setting the melting temperature and melting time of the die-casting raw material based on the estimated melting heat; performing melting and refining based on the melting temperature and melting time to obtain slag-removed molten die-casting raw material; spraying a release agent onto the inner surface of the die-casting cavity; then injecting the slag-removed molten die-casting raw material into the die-casting cavity; monitoring the die-casting cavity in real time; adjusting the temperature of the die-casting cavity based on the positive and negative temperature anomaly deviation values ​​of multiple temperature monitoring sub-regions of the die-casting cavity; and removing the die-casting components from the die-casting cavity after it has cooled.

[0131] Furthermore, when the logical instructions in the aforementioned memory can be implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a portion of the 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 cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0132] In embodiment three, this application also provides a computer program product, which includes a computer program stored on a computer-readable storage medium. The computer program includes program instructions. When the program instructions are executed by the computer, the computer can execute a temperature control method for a die-casting mold for metal casting provided by the above methods. The method includes: obtaining the material type and weight of the pre-input die-casting raw material; calculating the estimated melting heat of the die-casting raw material based on the raw material type and quantity; setting the melting temperature and melting time of the die-casting raw material based on the estimated melting heat; performing melting and refining based on the melting temperature and melting time to obtain slag-removed molten die-casting raw material; spraying a release agent onto the inner surface of the die-casting cavity; then injecting the slag-removed molten die-casting raw material into the die-casting cavity; monitoring the die-casting cavity in real time; adjusting the temperature of the die-casting cavity based on the positive and negative temperature anomaly deviation values ​​of multiple temperature monitoring sub-regions of the die-casting cavity; and removing the die-casting device inside the die-casting cavity after the die-casting cavity has cooled down.

[0133] In embodiment four, this application also provides a computer-readable storage medium storing a computer program thereon. When executed by a processor, the computer program implements a temperature control method for a die-casting mold for metal casting provided above. The method includes: obtaining the material type and weight of a pre-input die-casting raw material; calculating the estimated melting heat of the die-casting raw material based on the raw material type and quantity; setting the melting temperature and melting time of the die-casting raw material based on the estimated melting heat; performing melting and refining based on the melting temperature and melting time to obtain slag-removed molten die-casting raw material; spraying a release agent onto the inner surface of the die-casting cavity; then injecting the slag-removed molten die-casting raw material into the die-casting cavity; monitoring the die-casting cavity in real time; adjusting the temperature of the die-casting cavity based on the positive and negative temperature anomaly deviation values ​​of multiple temperature monitoring sub-regions of the die-casting cavity; and removing the die-casting device inside the die-casting cavity after the die-casting cavity has cooled down.

[0134] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0135] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0136] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A method for temperature control of die-casting molds for metal casting, characterized in that, The methods include: Step S1: Obtain the material type and weight of the pre-input die casting raw material, and calculate the estimated melting heat of the die casting raw material based on the material type and quantity. Step S2: Set the melting temperature and melting time of the die casting raw material according to the estimated melting heat, and perform melting and refining based on the melting temperature and melting time to obtain slag-removed melted die casting raw material; Step S3: Spray a release agent onto the inner surface of the die casting cavity, and then inject the slag-removed molten die casting raw material into the die casting cavity, and monitor the die casting cavity in real time. Step S4: Adjust the temperature of the die-casting cavity based on the positive and negative temperature anomaly deviation values ​​of multiple temperature monitoring sub-regions of the die-casting cavity. Step S5: After the die-casting cavity has cooled down, remove the die-casting components from inside the die-casting cavity. Step S3 includes: performing die casting operations in the die casting cavity at the working die casting temperature, and monitoring the abnormal temperature deviation value of the die casting cavity. The specific process for monitoring the abnormal temperature deviation value is as follows: Step S371: Read the infrared image of the die-casting cavity during the die-casting operation using an infrared sensing device; set multiple temperature monitoring points at fixed intervals in the infrared image of the die-casting cavity, with each temperature monitoring point numbered n and n having an upper limit value of x. Step S372: Using the temperature monitoring point as the center and half of the multiple dividing intervals as the side length, divide the infrared image into multiple temperature monitoring sub-regions. The number of each temperature monitoring sub-region is the same as the number of the corresponding temperature monitoring point. Step S373: For any temperature monitoring sub-region, read the pixel values ​​of all pixels in the temperature sub-region, and divide the pixel value of each pixel into R value component Ri, G value component Gi and B value component Bi; where i is the pixel number, i=1,2,...,z, and z is the upper limit of the number; Step S374: Calculate the pixel comparison value XBi for each pixel using the following formula: XBi = Ri×A1 + Gi×A2 + Bi×A3; where A1, A2, and A3 are weighting coefficients, and A2 > A1 > A3; Step S375: Sum the pixel comparison values ​​of all pixels in the same temperature monitoring sub-region to obtain the pixel comparison mean; then calculate the pixel comparison standard deviation of the same temperature monitoring sub-region. Step S376: Subtract the standard deviation of pixel comparison from the mean of pixel comparison as the left endpoint of the interval, and add the standard deviation of pixel comparison to the mean of pixel comparison as the right endpoint of the interval; construct the filtering interval based on the left and right endpoints of the interval. Iterate through the pixel comparison values ​​of all pixels and compare each pixel comparison value with the selected range; If the pixel comparison value of a pixel is less than the left endpoint of the interval or greater than the right endpoint of the interval, that is, the pixel comparison value is outside the filtering interval, then the corresponding pixel is recorded as an abnormal temperature pixel. If the pixel comparison value of a pixel is greater than or equal to the left endpoint of the interval or less than or equal to the right endpoint of the interval, that is, the pixel comparison value is within the filtering interval, then no operation is performed; Step S377: Record the pixel comparison values ​​of all abnormal temperature pixels. Subtract the average pixel comparison value from the pixel comparison value to obtain the comparison deviation value of the corresponding abnormal temperature pixel. Sum all comparison deviation values ​​greater than zero in the same temperature monitoring sub-region to obtain the positive temperature abnormality deviation value of the corresponding temperature monitoring sub-region. Sum all comparison deviation values ​​less than zero in the same temperature monitoring sub-region to obtain the negative temperature abnormality deviation value of the corresponding temperature monitoring sub-region. Step S378: Calculate the positive and negative temperature anomaly deviation values ​​for all temperature sub-regions.

2. The method for temperature control of a die-casting mold for metal casting according to claim 1, characterized in that, The calculation process for the estimated heat of fusion is as follows: Step S11: Identify the melting point temperature (WD) of the die-casting raw material based on its material type. 原 Compared with the specific heat capacity of raw materials C 原 ; Step S12, read the temperature of the die-casting mold at the initial moment and record it as WD. 压 ; Step S13: Calculate the estimated melting heat YR of the die-casting raw material using the formula. 原 The formula is as follows: YR 原 =ZL 原 ×C 原 ×(WD 原 -WD 压 )+QR 原 Among them, ZL 原 For raw material weight, QR 原 This refers to the latent heat of the die-casting raw materials.

3. The method for temperature control of a die-casting mold for metal casting according to claim 1, characterized in that, Step S2 includes the following sub-steps: Step S21: Scan the image of the outer surface of the die-casting raw material and automatically calculate the total area MJ of the outer surface of the die-casting raw material based on the modeling software. Step S22: Record the distance from the geometric center of the die-casting raw material to any point on the outer surface as the calibration distance, and select the longest calibration distance as the maximum heating distance JL of the die-casting raw material; Step S23: Calculate the heat flow rate RLL of the die-casting raw material using Fourier's law of heat conduction. The specific calculation formula is as follows: In the formula, K is the thermal conductivity of the die-casting raw material, and the negative sign before the thermal conductivity indicates that the heat transfer direction is opposite to the temperature gradient direction. Step S24: The estimated heating time is obtained by dividing the estimated melting heat of the die-casting raw material by the heat flow rate of the die-casting raw material.

4. The method for temperature control of a die-casting mold for metal casting according to claim 3, characterized in that, Step S2 further includes the following sub-steps: Step S25: Place the die casting raw material in a metal melting chamber, record the melting point temperature of the raw material as the melting temperature, record the estimated heating time as the melting time, and process the die casting raw material based on the melting temperature and melting time to obtain molten die casting raw material. Step S26: Add a refining agent to the molten die casting raw material to adsorb oxide impurities in the molten die casting raw material through a chemical reaction and precipitate raw material residue. Step S27: Add a covering agent to the molten die casting raw material, let it stand for a fixed time, remove the slag on the surface of the molten die casting raw material with a skimming tool, and repeat the operation until constant weight is achieved; Step S28: Place the slag-removed molten die-casting raw material back into the metal melting chamber and heat until it is completely melted to obtain slag-removed molten die-casting raw material.

5. The method for temperature control of a die-casting mold for metal casting according to claim 1, characterized in that, Step S3 includes the following sub-steps: Step S31: Obtain the volume TJ corresponding to the die-casting cavity. 腔 The volume of the overflow tank (TJ) 流 And the volume of the exhaust channel TJ 气 ; Step S32: Calculate the calculated injection volume TJ of the die-casting cavity using the formula. 注 The formula is as follows: TJ 注 =(TJ 腔 +TJ 流 +TJ 气 )×(1+α)×(1+β;where α is the shrinkage compensation coefficient and β is the process loss coefficient; Step S33: Calculate the calculated injection weight ZL of the die-casting cavity using the formula. 注 The formula is as follows: ZL 注 =ρ 熔 ×TJ 注 In the formula, ρ 熔 This refers to the density of the die-casting raw material in its molten state.

6. The method for temperature control of a die-casting mold for metal casting according to claim 5, characterized in that, Step S3 further includes the following sub-steps: Step S34: Inject the slag-removed molten die-casting raw material (calculated injection weight) into the pressure chamber, reduce the pressure inside the pressure chamber to a negative pressure ≤10 mbar to allow the gas inside the pressure chamber to escape; connect the vacuum pump to the exhaust tank, reduce the pressure inside the die-casting cavity to 10 mbar using the vacuum pump, and then connect the pressure chamber to the die-casting cavity. Step S35: Increase the pressure in the pressure chamber. Under high pressure, the slag-removing and molten die-casting raw materials are injected into the die-casting cavity through multiple inner gates. Step S36: Calculate the working die-casting temperature of the die-casting cavity; Step S37: The die-casting cavity is used for die-casting at the working die-casting temperature, and the abnormal temperature deviation value of the die-casting cavity is monitored.

7. The method for temperature control of a die-casting mold for metal casting according to claim 6, characterized in that, The calculation process for the working die-casting temperature is as follows: Step S361: Collect historical die casting data that is the same as the material type corresponding to the die casting raw material; wherein, the historical die casting data includes the historical die casting temperature and the total number of die castings and the number of die casting failures corresponding to the historical die casting temperature; Step S362: Die casting success rate corresponding to different historical die casting temperatures is obtained by dividing the difference between the total number of die castings and the number of die casting failures by the total number of die castings; the historical die casting temperatures are arranged in descending order of die casting success rate. Step S363: Select the top three historical die-casting temperatures, sum them up, and take the average value as the working die-casting temperature of the die-casting cavity.

8. The method for temperature control of a die-casting mold for metal casting according to claim 1, characterized in that, Step S4 includes the following sub-steps: Step S41: Obtain the positive and negative temperature anomaly deviation values ​​for the temperature monitoring sub-region; Step S42: Perform cooling correction control on the abnormal temperature pixel corresponding to the positive temperature abnormal deviation value in the temperature monitoring sub-region, that is, reduce the real-time temperature of the abnormal temperature pixel to the working die-casting temperature. Step S43: Perform temperature rise correction control on the abnormal temperature pixel corresponding to the negative temperature abnormal deviation value in the temperature monitoring sub-region, that is, raise the real-time temperature of the abnormal temperature pixel to the working die casting temperature.

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