Smelting process of high-quality zinc alloy die casting

Abstract

The invention relates to the technical field of zinc structure functional material preparation, in particular to a high-quality zinc alloy die casting smelting process which comprises the steps that zinc alloy casting production raw materials are prepared by weight, and the production raw materials are sequentially subjected to oil removal, cleaning and drying treatment to obtain clean raw materials; smelting the clean raw materials in a graphite crucible to obtain molten liquid; dross is fished out from the molten liquid, and slag-free zinc alloy liquid is obtained; the slag-free zinc alloy liquid is poured into a die-casting die for die-casting forming, annealing treatment is conducted, and a zinc alloy die casting is obtained; grinding, polishing and washing the zinc alloy die casting to obtain the zinc alloy die casting subjected to surface treatment; the zinc alloy die casting subjected to surface treatment is subjected to laser treatment, and the zinc alloy die casting subjected to laser treatment is obtained; and the zinc alloy casting subjected to laser treatment is washed and dried, and the high-quality zinc alloy die casting is obtained. By controlling the smelting temperature, the toughness of the zinc alloy die casting is improved.

Description

Technical Field

[0001] This application relates to the technical field of the preparation of zinc structural functional materials, and specifically relates to a melting process for high-quality zinc alloy die-castings. Background Art

[0002] During the melting process of zinc alloy die-castings, if the melting temperature is too high or too low, it will have a great impact on the toughness of zinc alloy die-castings. Accurately controlling and adjusting the melting temperature during the melting process helps the uniform distribution of alloying elements and the refinement treatment of the alloy structure during the melting process, which is the key to improving the toughness of zinc alloy die-castings.

[0003] During the melting process of zinc alloy die-castings, most of the existing technologies directly control the melting temperature within a small change range during the melting process to avoid the adverse effects caused by too high or too low melting temperature. However, this method lacks in-depth analysis of the relationship between the temperature of the alloy liquid and the heat treatment of alloying elements, and cannot accurately control and adjust the melting temperature during the melting process, making it impossible to meet the requirements of alloying elements for the melting temperature at different melting times, easily resulting in non-uniform distribution of alloying elements and poor effect of the refinement treatment of the alloy structure during the melting process, and ultimately having a greater adverse impact on the toughness of zinc alloy die-castings. Summary of the Invention

[0004] In order to solve the above technical problems, this application provides a melting process for high-quality zinc alloy die-castings to solve the existing problems.

[0005] The melting process for high-quality zinc alloy die-castings of this application adopts the following technical scheme:

[0006] S1: Prepare the production raw materials for zinc alloy castings by weight, and perform degreasing, cleaning and drying treatments on the production raw materials in sequence to obtain clean raw materials;

[0007] S2: Perform a melting treatment on the clean raw materials in a graphite crucible to obtain a molten liquid. Among them, the melting temperature is controlled, and the specific process is as follows:

[0008] S201: During the melting process, select multiple measurement positions from the alloy liquid in the graphite crucible, and obtain the temperature data at any measurement position at each melting moment;

[0009] S202: Take the preset number of acquisition moments before each smelting moment as the short-time smelting moments of each smelting moment; determine the temperature difference consistency between each smelting moment and any of its short-time smelting moments by analyzing the dispersion degree of the temperature data differences at all measurement positions between each smelting moment and any of its short-time smelting moments; between each smelting moment and all short-time smelting moments, determine the smelting effectiveness of each smelting moment by analyzing the differences in adjacent temperature difference consistencies and the average distribution of the temperature difference consistencies between the current smelting moment and all short-time smelting moments.

[0010] S203: Determine the smelting refinement value of each smelting moment by analyzing the change situation and dispersion degree of the temperature data at all measurement positions under each smelting moment, in combination with the smelting effectiveness.

[0011] S204: Based on the smelting refinement value, regulate the smelting temperature of the current smelting moment.

[0012] S3: Scoop out the dross from the molten liquid to obtain slag-free zinc alloy liquid.

[0013] S4: Pour the slag-free zinc alloy liquid into a die-casting mold for die-casting and perform annealing treatment to obtain zinc alloy die-castings.

[0014] S5: Grind, polish and rinse the zinc alloy die-castings to obtain zinc alloy die-castings after surface treatment.

[0015] S6: Perform laser treatment on the zinc alloy die-castings after surface treatment to obtain zinc alloy die-castings after laser treatment.

[0016] S7: Rinse and dry the zinc alloy castings after laser treatment to obtain high-quality zinc alloy die-castings.

[0017] Preferably, the production raw materials include: 95.3 - 96.4 parts of metallic zinc, 3.5 - 4.5 parts of metallic aluminum, 0.03 - 0.05 parts of metallic magnesium, 0.1 - 0.2 parts of metallic copper, 0.32 - 0.4 parts of Al-Ti-B master alloy.

[0018] Preferably, during the smelting process, the initial smelting temperature is controlled at 415 - 420 °C, and the electromagnetic stirring time is 15 - 20 min.

[0019] Preferably, the method for determining the temperature difference consistency between each smelting moment and any of its short-time smelting moments is as follows:

[0020] Record the difference between the temperature data at the same measurement position between each smelting moment and any of its short-time smelting moments as the temperature time-series difference at the same measurement position between each smelting moment and any of its short-time smelting moments.

[0021] Denote the degree of dispersion of the temperature time series differences at all measurement positions between each smelting moment and any of its short-time smelting moments as the discrete temperature difference value between each smelting moment and any of its short-time smelting moments;

[0022] The temperature difference consistency R between smelting moment j and its t-th short-time smelting moment j,t has the following expression: R j,t = exp(-σ j,t ); where σ j,t represents the discrete temperature difference value between smelting moment j and its t-th short-time smelting moment; exp() represents the exponential function with the natural constant as the base.

[0023] Preferably, the expression for the smelting effectiveness of each smelting moment is: where G j represents the smelting effectiveness of smelting moment j; R j,t , R j,t-1 respectively represent the temperature difference consistencies between smelting moment j and its t-th and t-1-th short-time smelting moments; represents the mean value of the temperature difference consistencies between smelting moment j and all its short-time smelting moments; T j represents the number of all short-time smelting moments of smelting moment j; exp() represents the exponential function with the natural constant as the base.

[0024] Preferably, the method for determining the smelting refinement value of each smelting moment is as follows:

[0025] Obtain the first-order difference sequence of the temperature data at all measurement positions at each smelting moment, calculate the mean value of the absolute values of all elements in the first-order difference sequence, and denote it as the temperature difference mean value of each smelting moment;

[0026] Denote the degree of dispersion of the temperature data at all measurement positions at each smelting moment as the temperature dispersion degree of each smelting moment;

[0027] Calculate the product of the temperature difference mean value and the temperature dispersion degree of each smelting moment, and take the normalized value of the ratio of the product to the smelting effectiveness as the smelting refinement value of each smelting moment.

[0028] Preferably, the regulation of the smelting temperature at the current smelting moment includes:

[0029] Take the smelting refinement values of all smelting moments within a preset time period before the current smelting moment as the input of the threshold segmentation algorithm, and output the segmentation threshold as the adjustment judgment coefficient for the current smelting moment;

[0030] Based on the difference between the average distribution of the refining values at all melting moments within a preset time period before the current melting moment and the adjustment judgment coefficient, and combined with the average distribution of the temperature data at all measurement positions at the previous adjacent moment of the current capacity moment, determine the melting feedback temperature at the current moment. The expression for the melting feedback temperature D at the current moment is as follows: In the formula, De represents the mean value of the temperature data at all measurement positions at the previous melting moment of the current melting moment; represents the mean value of the refining values at all short-time melting moments within a preset time period before the current melting moment; μ represents the adjustment judgment coefficient at the current melting moment; Dc represents the preset adjustable temperature;

[0031] Adjust the melting temperature at the current moment to the melting feedback temperature at the current moment.

[0032] Preferably, the sandpaper used in the S5 grinding process is one of 240, 800, and 1200 grit sandpaper.

[0033] Preferably, during the laser treatment process, the laser power is 30 - 40 kW, the current is 100 - 200 A, the pulse width is 1 - 2 mm, and the defocus amount is 50 - 60 mm.

[0034] Preferably, the flushing solution in the S7 flushing process is plasma water.

[0035] An embodiment of the present application provides a melting process for high-quality zinc alloy die-castings, and this process includes the following steps:

[0036] The present application has at least the following beneficial effects:

[0037] By analyzing the consistency of the differences in the temperature of the alloy liquid at the same measurement position at different times during the smelting process, the temperature difference consistency between different smelting moments is obtained. Combining the change fluctuations and average level of the temperature difference consistency, the effective effect of heat-treating alloy elements during the smelting process is analyzed, and the smelting effectiveness is obtained, which can reflect the effective degree of heat-treating alloy elements during the smelting process, and can judge the uniformity of the distribution of alloy elements, thereby guiding the regulation of the smelting temperature, enabling better dissolution and diffusion of alloy elements in the molten liquid and achieving uniform distribution. Further, by combining the smelting effectiveness and the characteristics of the uneven temperature distribution in the alloy liquid during the smelting process, the refining effect of smelting alloy elements in the graphite crucible is accurately measured to obtain the smelting refinement value, which is used to more accurately control and adjust the smelting temperature in the graphite crucible in the future. Furthermore, by using the average level of the smelting refinement value in a short period of time before the current smelting moment, the smelting temperature is more accurately feedback-regulated to meet the requirements of alloy elements for the smelting temperature at different smelting moments, making the distribution of alloy elements more uniform during the smelting process and the refinement treatment of the alloy structure more effective, and improving the toughness of zinc alloy die castings. Brief Description of the Drawings

[0038] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0039] Figure 1 It is a flowchart of the steps of a smelting process for high-quality zinc alloy die castings provided by an embodiment of the present application;

[0040] Figure 2 It is a schematic diagram of the zinc alloy smelting temperature regulation process provided by an embodiment of the present application. Detailed Embodiments

[0041] In order to further elaborate on the technical means and effects adopted by the present application to achieve the intended invention purpose, the following, in combination with the drawings and preferred embodiments, details the specific embodiments, structures, features and effects of a smelting process for high-quality zinc alloy die castings proposed according to the present application. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. In addition, the specific features, structures or characteristics in one or more embodiments can be combined in any suitable form.

[0042] Unless otherwise defined, terms such as "including", "comprising" or any other variants thereof are intended to cover non-exclusive inclusion, such that a circuit structure, article or device comprising a series of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such article or device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the presence of additional identical elements in the article or device comprising said element. Additionally, the term "and / or" as used herein includes any and all combinations of one or more of the associated listed items. All technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field to which this application belongs. The following specifically describes the specific solution of a melting process for high-quality zinc alloy die-castings provided by this application in conjunction with the accompanying drawings.

[0043] The following specifically describes the specific solution of a melting process for high-quality zinc alloy die-castings provided by this application in conjunction with the accompanying drawings.

[0044] Example 1

[0045] A melting process for high-quality zinc alloy die-castings provided by Example 1. Specifically, please refer to Figure 1 , and this process includes the following steps:

[0046] S1: Prepare the raw materials for zinc alloy casting production by weight, and perform degreasing, cleaning, and drying treatments on the production raw materials in sequence to obtain clean metal raw materials.

[0047] Production raw material preparation: Prepare the production raw materials for zinc alloy die-castings by weight. In this example, 95.3 parts of metallic zinc, 3.5 parts of metallic aluminum, 0.03 parts of metallic magnesium, 0.1 part of metallic copper, and 0.32 parts of Al-Ti-B master alloy are used as the production raw materials for zinc alloy die-castings to produce high-quality zinc alloy die-castings.

[0048] Degreasing, cleaning, and drying treatments: Place the above-mentioned production raw materials in an ultrasonic degreaser for degreasing treatment respectively. Further, wash and dry the production raw materials after degreasing treatment with ethanol respectively to obtain clean raw materials. The clean raw materials are divided into two categories, namely clean metal raw materials and clean Al-Ti-B master alloy raw materials.

[0049] S2: Perform melting treatment on the clean raw materials in a graphite crucible to obtain a molten liquid.

[0050] Melting preparation: Prepare clean nickel-based soft magnetic alloy chips as the stirring medium for electromagnetic stirring, place the clean nickel-based soft magnetic alloy chips at the bottom of the graphite crucible, and then place the clean raw materials in the graphite crucible to cover the nickel-based soft magnetic alloy chips.

[0051] Smelting treatment: Turn on the heating device to smelt the raw materials in the graphite crucible. In this embodiment, the initial smelting temperature is selected as 415°C. Slowly add the clean aluminum-titanium-boron master alloy raw materials into the molten alloy after the raw materials in the graphite crucible are fully melted, and turn on the electromagnetic stirrer to stir under the condition of maintaining heating. In this embodiment, the electromagnetic stirring time is set to 15 minutes. Subsequently, a molten liquid is obtained after the alloy raw materials in the graphite crucible are fully melted.

[0052] During the smelting process of zinc alloy die-castings, if the smelting temperature is too high or too low, it will have a great impact on the toughness of zinc alloy die-castings. Accurately controlling and adjusting the smelting temperature during the smelting process helps the uniform distribution of alloy elements and the refinement of alloy structure during the smelting process, which is the key to improving the toughness of zinc alloy die-castings. Therefore, based on the temperature change at different depths of the alloy liquid at the same smelting moment and the temperature difference between different smelting moments, the smelting temperature during the smelting process is controlled. The specific process is as follows:

[0053] S201: During the smelting process, select multiple measurement positions from the alloy liquid in the graphite crucible, and obtain the temperature data at any measurement position at each smelting moment.

[0054] During the smelting process of zinc alloy die-castings, uniformly select K measurement positions from the alloy liquid in the graphite crucible and label the K measurement positions. Measure the temperature data at the K measurement positions at each smelting moment during the smelting process through a thermocouple temperature sensor. In this embodiment, the measurement time interval is 5 s, and the number of measurement positions K is 16. The implementer can take values for the measurement time interval and the number of measurement positions according to the actual situation, and this embodiment does not make special restrictions.

[0055] S202: Take a preset number of acquisition moments before each smelting moment as the short-term smelting moments of each smelting moment; determine the temperature difference consistency between each smelting moment and any of its short-term smelting moments by analyzing the dispersion degree of the temperature data differences at all measurement positions between each smelting moment and any of its short-term smelting moments; between each smelting moment and all short-term smelting moments, determine the smelting effectiveness of each smelting moment by analyzing the differences between adjacent temperature difference consistencies and the average distribution of the temperature difference consistencies between the current smelting moment and all short-term smelting moments.

[0056] During the smelting process of alloy elements in a graphite crucible, the temperature uniformity in the alloy liquid is greatly affected by the heat transfer in the graphite crucible. If there are significant temperature differences at different positions in the alloy liquid, to a certain extent, it reflects the uneven distribution of alloy elements in the alloy liquid. Moreover, the more uneven the distribution of alloy elements in the alloy liquid, the more it can reflect the poor refinement effect of alloy elements in the alloy liquid. However, in the early stage of smelting alloy elements, the characteristics of temperature non-uniformity and uneven distribution of alloy elements are generally more obvious. Measuring the refinement characteristics of alloy elements only based on the temperature non-uniformity characteristics at a certain moment in the alloy liquid will result in a large error, which will affect the accuracy of subsequent control and adjustment of the smelting temperature. Therefore, in order to more accurately control and adjust the smelting temperature, it is necessary to more accurately analyze the refinement characteristics of alloy elements during the smelting process.

[0057] In order to analyze the smelting characteristics of alloy elements in a short time, calculate the time intervals between each smelting moment and all other smelting moments, and arrange the time intervals in ascending order. The first preset number of smelting moments in the sorted result are used as the short-time smelting moments of each smelting moment.

[0058] It should be noted that the value of the preset number is set manually. In this embodiment, the value of the preset number is 10. Implementers can also set it according to specific situations by themselves, and this embodiment does not make special restrictions.

[0059] Furthermore, the difference between the temperature data at the same measurement position at each smelting moment and its any short-time smelting moment is denoted as the temperature time-series difference at the same measurement position between each smelting moment and its any short-time smelting moment.

[0060] The degree of dispersion of the temperature time-series differences at all measurement positions between each smelting moment and its any short-time smelting moment is denoted as the discrete temperature difference value between each smelting moment and its any short-time smelting moment. The smaller the discrete temperature difference value, the higher the consistency of the temperature distribution difference, and the better the smelting effect of the alloy elements in the graphite crucible at this time, which can make the smelting temperature in the alloy liquid change more evenly.

[0061] It should be understood that there are many methods to measure the difference between data. In this embodiment, the absolute value of the difference between the temperature data at the same measurement position at each smelting moment and its any moment is used as the difference between the temperature data at the same measurement position at each smelting moment and its any moment, that is, the temperature time-series difference at the same measurement position between each smelting moment and its any short-time smelting moment. In actual application processes, as other implementation methods, implementers can also use other methods to measure the difference between data, such as ratios. Regarding the selection of methods to measure the difference between data, this embodiment does not make special restrictions.

[0062] It should be noted that there are many methods to measure the degree of data dispersion. In this embodiment, the coefficient of variation of the differences between all measurement positions at each smelting moment and any short-time smelting moment is used as the degree of dispersion of the differences between all measurement positions at each smelting moment and any short-time smelting moment, that is, the discrete temperature difference value. In actual application processes, as other implementation manners, implementers can also adopt other methods to measure the degree of data dispersion, such as variance and standard deviation. Regarding the selection of methods for measuring the degree of data dispersion, this embodiment does not make special restrictions.

[0063] Among them, the calculation method of the coefficient of variation is a well-known technology, and its specific calculation process will not be elaborated here.

[0064] Furthermore, based on the discrete temperature difference value, the temperature difference consistency between each smelting moment and any short-time smelting moment is determined. The specific expression is:

[0065] The temperature difference consistency R between the smelting moment j and its t-th short-time smelting moment j,t is expressed as: R j,t = exp(-σ j,t ); in the formula, σ j,t represents the discrete temperature difference value between the smelting moment j and its t-th short-time smelting moment; exp() represents the exponential function with the natural constant as the base.

[0066] From the temperature difference consistency between each smelting moment and any short-time smelting moment, it can be understood that there is an inverse relationship between the discrete temperature difference value and the temperature difference consistency. The temperature difference consistency reflects the consistency of the temperature distribution on the alloy liquid between different smelting moments. If the discrete temperature difference value between the current smelting moment and its short-time smelting moment is smaller, the temperature difference consistency is larger, indicating that the smelting effect of the alloy elements in the graphite crucible at this time is better, and it can make the smelting temperature in the alloy liquid change more evenly; conversely, if the discrete temperature difference value between the current smelting moment and its short-time smelting moment is larger, the temperature difference consistency is smaller, indicating that the smelting effect of the alloy elements in the graphite crucible at this time is worse.

[0067] If the change fluctuation of the temperature difference consistency within a short time is smaller and the average level of the temperature difference consistency is higher, it can better reflect the effective role of heat treatment on alloy elements during the smelting process, and can more prominently illustrate the refinement characteristics during the smelting process of alloy elements in the graphite crucible, which is beneficial to more accurately controlling and adjusting the smelting temperature in the graphite crucible subsequently.

[0068] Furthermore, the smelting effectiveness of each smelting moment during the smelting process is calculated, specifically:

[0069] The expression of the smelting effectiveness of the smelting moment j is: In the formula, G jDenote the melting effectiveness at melting moment j; R j,t and R j,t-1 respectively denote the temperature difference consistency between melting moment j and its t-th and (t - 1)-th short-time melting moments; Denote the mean value of the temperature difference consistency between melting moment j and all its short-time melting moments; T j Denote the number of all short-time melting moments at melting moment j; exp() represents the exponential function with the natural constant as the base.

[0070] It can be understood from the melting effectiveness at each melting moment that the melting effectiveness reflects the effective degree of heat treatment of alloy elements during the melting process. If the difference between the t-th and (t - 1)-th temperature difference consistencies is smaller and the mean value of the temperature difference consistency is larger, the melting effectiveness is larger, indicating a higher effective degree of heat treatment of alloy elements, better characterizing the refinement effect of alloy elements in the graphite crucible at this time, being more conducive to the dissolution and diffusion of alloy elements in the graphite crucible, and avoiding the uneven internal structure of the produced zinc alloy die-castings, thereby improving the toughness index of the zinc alloy die-castings;

[0071] On the contrary, if the difference between the t-th and (t - 1)-th temperature difference consistencies is larger and the mean value of the temperature difference consistency is smaller, the melting effectiveness is smaller, indicating a lower effective degree of heat treatment of alloy elements, worse characterizing the refinement effect of alloy elements in the graphite crucible at this time, and being less conducive to the dissolution and diffusion of alloy elements in the graphite crucible.

[0072] S203: By analyzing the change situation and dispersion degree of the temperature data at all measurement positions at each melting moment, and combining the melting effectiveness, determine the melting refinement value at each melting moment.

[0073] Meanwhile, if the temperature non-uniformity of the alloy liquid in the graphite crucible at a certain melting moment is higher, to a certain extent, it indicates that the distribution uniformity of alloy elements in the alloy liquid at this time is worse, and it is less conducive to the refinement effect of alloy elements in the alloy liquid.

[0074] To more accurately analyze the refinement characteristics of alloy elements during the melting process, obtain the first-order difference sequence of the temperature data at all measurement positions at each melting moment, calculate the mean value of the absolute values of all elements in the first-order difference sequence, and denote it as the temperature difference mean value at each melting moment;

[0075] Furthermore, denote the dispersion degree of the temperature data at all measurement positions at each melting moment as the temperature dispersion degree at each melting moment;

[0076] Calculate the product of the temperature difference mean value and the temperature dispersion degree at each melting moment, and take the normalized value of the ratio of the product to the melting effectiveness as the melting refinement value at each melting moment.

[0077] It can be understood from the smelting refinement values at each smelting moment that if the average temperature difference is larger and the temperature dispersion is larger, it reflects that the temperature distribution of the alloy liquid during the smelting process is more uneven, indicating that there are significant differences in the temperatures at different measurement positions on the alloy liquid in the graphite crucible at this time, which is less conducive to the refinement of alloy elements in the alloy liquid; and the smaller the smelting effectiveness, the less conducive to the dissolution and diffusion of alloy elements. Therefore, the larger the obtained smelting refinement value, the worse the refinement effect of alloy elements at this time.

[0078] Conversely, if the average temperature difference is smaller and the temperature dispersion is smaller, it reflects that the temperature distribution of the alloy liquid during the smelting process is more uniform, indicating that the differences in the temperatures at different measurement positions on the alloy liquid in the graphite crucible at this time are smaller, which is conducive to the refinement of alloy elements in the alloy liquid; and the larger the smelting effectiveness, the more conducive to the dissolution and diffusion of alloy elements. Therefore, the larger the obtained smelting refinement value, the better the refinement effect of alloy elements at this time.

[0079] S204: Based on the smelting refinement value, regulate the smelting temperature at the current smelting moment.

[0080] If the average level of the smelting refinement values in the short period before the current smelting moment is lower, the smelting temperature in the graphite crucible should be appropriately increased at this time to improve the dissolution ability and diffusion ability of alloy elements, so as to maintain a better refinement effect of alloy elements during the smelting process; conversely, if the average level of the smelting refinement values in the short period before the current smelting moment is higher, the alloy raw materials in the graphite crucible are closer to being fully melted into alloy liquid at this time, and the smelting temperature in the graphite crucible should be appropriately decreased at this time to avoid burning out beneficial elements in the alloy liquid, increasing zinc slag while reducing the purity of the alloy liquid.

[0081] Furthermore, take the smelting refinement values at all smelting moments within a preset time period before the current smelting moment as the input of the threshold segmentation algorithm, and output the segmentation threshold as the adjustment judgment coefficient for the current smelting moment.

[0082] It should be noted that the value of the preset time period is set manually. In this embodiment, the value of the preset time period is 1 min, and the implementer can also set it according to the specific situation by himself / herself, and this embodiment does not make special restrictions.

[0083] In addition, it should be understood that there are many commonly used threshold segmentation algorithms. In this embodiment, the maximum between-class variance is used to obtain the segmentation threshold. In the actual application process, as other implementation manners, the implementer can also use other threshold segmentation methods. Regarding the selection of the threshold segmentation algorithm, this embodiment does not make special restrictions.

[0084] Among them, the maximum between-class variance algorithm is a well-known technology, and its specific principle process will not be elaborated here.

[0085] The expression for the melting feedback temperature D at the current melting moment is as follows: In the formula, De represents the average value of the temperature data at all measurement positions at the previous melting moment before the current melting moment; represents the average value of the melting refinement values at all melting moments within a preset time duration before the current melting moment; μ represents the adjustment judgment coefficient at the current melting moment; Dc represents the preset adjustable temperature;

[0086] Adjust the melting temperature at the current melting moment during the melting process to the melting feedback temperature at the current moment. In this embodiment, it is selected to adjust the temperature of the molten metal in the graphite crucible once every 2 minutes. The implementer can also set the interval time of the temperature adjustment according to the specific situation by himself / herself, and this embodiment does not make special restrictions.

[0087] It should be noted that the value of the preset adjustable temperature is set artificially. The purpose is to limit the change range of the adjusted temperature and avoid burning loss of alloy elements during the melting process due to too large an adjustment temperature range. Therefore, in this embodiment, the value of the preset adjustable temperature is set to 12.

[0088] Preferably, the schematic diagram of the zinc alloy melting temperature control process provided in this embodiment is as Figure 2 shown.

[0089] So far, by controlling the melting temperature during the melting process, the melting of the alloy liquid is completed to obtain the molten liquid.

[0090] S3: Scoop out the floating slag from the molten liquid to obtain slag-free zinc alloy liquid.

[0091] After scooping out the floating slag from the molten liquid after melting, stir it, and then scoop out the remaining floating slag again to obtain slag-free zinc alloy liquid.

[0092] S4: Pour the slag-free zinc alloy liquid into a die-casting mold for die-casting and perform annealing treatment to obtain zinc alloy die-castings.

[0093] Die-casting: After pouring the slag-free zinc alloy liquid into the die-casting mold for die-casting, cool it to room temperature at normal temperature to obtain a zinc alloy die-casting blank.

[0094] Homogenization annealing treatment: Perform homogenization annealing treatment on the zinc alloy die-casting blank to make the alloy elements evenly distributed throughout the zinc alloy die-casting to obtain zinc alloy die-castings.

[0095] S5: Grind, polish and rinse the zinc alloy die-castings to obtain the zinc alloy die-castings after surface treatment.

[0096] The surface of the zinc alloy die-casting is polished with sandpaper and rinsed. In this embodiment, during the polishing process, No. 240 sandpaper is used to polish the zinc alloy die-casting step by step to obtain the zinc alloy die-casting after surface treatment.

[0097] S6: Laser-treat the zinc alloy die-casting after surface treatment to obtain the zinc alloy die-casting after laser treatment.

[0098] Laser-treat the zinc alloy die-casting after surface treatment. Among them, in this embodiment, the laser power is set to 30 kW, the current is set to 100 A, the pulse width is set to 1 mm, and the defocus amount is 50 mm to improve the surface performance of the zinc alloy die-casting and obtain the zinc alloy die-casting after laser treatment.

[0099] S7: Rinse and dry the zinc alloy casting after laser treatment to obtain a high-quality zinc alloy die-casting.

[0100] The zinc alloy die-casting after laser treatment is rinsed with plasma water and then dried to remove the residual corrosive liquid and impurities, obtaining a high-quality zinc alloy die-casting with zinc structural function.

[0101] Example 2

[0102] A melting process for a high-quality zinc alloy die-casting provided by Example 2. Specifically, please refer to Figure 1 , and this process includes the following steps:

[0103] S1: Prepare the production raw materials for the zinc alloy casting, and perform degreasing, cleaning, and drying treatments on the production raw materials in sequence to obtain clean metal raw materials.

[0104] Production raw material preparation: Prepare the production raw materials for the zinc alloy die-casting by weight. In this embodiment, 95.8 parts of metallic zinc, 4 parts of metallic aluminum, 0.04 parts of metallic magnesium, 0.15 parts of metallic copper, and 0.36 parts of aluminum-titanium-boron master alloy are used as the production raw materials for the zinc alloy die-casting to produce high-quality zinc alloy die-castings.

[0105] Among them, the operations of degreasing, cleaning, and drying the production raw materials are the same as those in Example 1.

[0106] S2: Perform melting treatment on the clean raw materials in a graphite crucible to obtain a molten liquid.

[0107] In this embodiment, during the melting treatment process, the initial melting temperature is selected as 418 °C, the electromagnetic stirring time is set to 18 min, and the melting preparation operation and other steps during the melting treatment process are the same as those in Example 1.

[0108] S3: Skim the scum from the molten liquid to obtain slag-free zinc alloy liquid.

[0109] S4: Pour the slag-free zinc alloy liquid into a die-casting mold for die-casting and annealing treatment to obtain a zinc alloy die-casting.

[0110] S5: Grind, polish and rinse the zinc alloy die-casting to obtain a zinc alloy die-casting with surface treatment. In this embodiment, during the grinding process, the zinc alloy die-casting is gradually ground and polished with 800-grit sandpaper, and the remaining operations are the same as in Embodiment 1.

[0111] S6: Perform laser treatment on the zinc alloy die-casting with surface treatment to obtain a zinc alloy die-casting after laser treatment.

[0112] Perform laser treatment on the zinc alloy die-casting with surface treatment. Among them, in this embodiment, the laser power is set to 35 kW, the current is set to 150 A, the pulse width is set to 1.5 mm, and the defocus amount is 55 mm to improve the surface performance of the zinc alloy die-casting and obtain a zinc alloy die-casting after laser treatment.

[0113] S7: Rinse and dry the zinc alloy casting after laser treatment to obtain a high-quality zinc alloy die-casting.

[0114] Embodiment 3

[0115] A melting process for a high-quality zinc alloy die-casting provided by Embodiment 3. Specifically, please refer to Figure 1 , and this process includes the following steps:

[0116] S1: Prepare the raw materials for zinc alloy casting by weight, and perform degreasing, cleaning and drying treatments on the raw materials in sequence to obtain clean metal raw materials.

[0117] Preparation of production raw materials: Prepare the production raw materials for zinc alloy die-castings by weight. In this embodiment, 96.4 parts of metallic zinc, 4.5 parts of metallic aluminum, 0.05 part of metallic magnesium, 0.2 part of metallic copper, and 0.4 part of aluminum-titanium-boron master alloy are used as the production raw materials for zinc alloy die-castings to produce high-quality zinc alloy die-castings.

[0118] Among them, the operations of degreasing, cleaning and drying the production raw materials are the same as in Embodiment 1.

[0119] S2: Perform melting treatment on the clean raw materials in a graphite crucible to obtain a molten liquid.

[0120] In this embodiment, during the melting treatment process, the initial melting temperature is selected as 420 °C, the electromagnetic stirring time is set to 20 min, and the melting preparation operation and other steps during the melting treatment process are the same as in Embodiment 1.

[0121] S3: Scoop out the floating slag from the molten liquid to obtain a slag-free zinc alloy liquid.

[0122] S4: Pour the slag-free zinc alloy liquid into a die-casting mold for die-casting and annealing to obtain a zinc alloy die-casting.

[0123] S5: Grind, polish and rinse the zinc alloy die-casting to obtain a zinc alloy die-casting after surface treatment. In this embodiment, during the grinding process, 1200-grit sandpaper is used to gradually grind and polish the zinc alloy die-casting, and the remaining operations are the same as in Embodiment 1.

[0124] S6: Perform laser treatment on the zinc alloy die-casting after surface treatment to obtain a zinc alloy die-casting after laser treatment.

[0125] Perform laser treatment on the zinc alloy die-casting after surface treatment. In this embodiment, the laser power is set to 40 kW, the current is set to 200 A, the pulse width is set to 2 mm, and the defocus amount is 60 mm to improve the surface performance of the zinc alloy die-casting and obtain a zinc alloy die-casting after laser treatment.

[0126] S7: Rinse and dry the zinc alloy casting after laser treatment to obtain a high-quality zinc alloy die-casting.

[0127] Embodiment Comparison

[0128] To verify the effectiveness of the parameters of this application, multiple comparative examples are set in this application, specifically:

[0129] Comparative Example 1: Control the temperature of the melting process to be 415 °C all the time, and the remaining operations are the same as in Embodiment 1;

[0130] Comparative Example 2: Control the temperature of the melting process to be 418 °C all the time, and the remaining operations are the same as in Embodiment 2;

[0131] Comparative Example 3: Control the temperature of the melting process to be 420 °C all the time, and the remaining operations are the same as in Embodiment 3;

[0132] Perform physical property tests on the zinc alloy die-castings in the examples and comparative examples respectively. The performance test indexes include density, compressive strength, tensile strength, elongation and impact toughness. Among them, the toughness evaluation indexes are elongation and impact toughness. The performance comparison results of the zinc alloy die-castings in the examples and comparative examples are shown in Table 1:

[0133] Table 1 Zinc Alloy Performance Comparison Table

[0134]

[0135] It should be noted that the above order of the embodiments of the present application is only for description and does not represent the superiority or inferiority of the embodiments. In addition, the specific embodiments of this specification have been described. Moreover, the processes depicted in the drawings do not necessarily require the specific order or sequential order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0136] The embodiments in this specification are all described in a progressive manner. For the same or similar parts among the embodiments, reference can be made to each other. Each embodiment focuses on the differences from other embodiments.

[0137] The above-described embodiments are only used to illustrate the technical solutions of the present application and are not intended to limit them. Modifying the technical solutions recorded in the foregoing embodiments or equivalently replacing some of the technical features does not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application, and all should be included within the protection scope of the present application.

Claims

1. A smelting process for high-quality zinc alloy die castings, characterized in that: The process includes the following steps: S1: preparing raw materials for zinc alloy castings by weight, and degreasing, cleaning and drying the raw materials in sequence to obtain clean raw materials; S2: The clean raw material is melted in a graphite crucible to obtain a molten liquid, wherein the melting temperature is controlled. The specific process is as follows: S201: during the smelting process, multiple measurement positions are selected from the alloy liquid in the graphite crucible to obtain temperature data at any measurement position at each smelting time; S202: taking a preset number of collection moments before each smelting moment as the short-time smelting moment of each smelting moment; determining the temperature difference consistency between each smelting moment and any short-time smelting moment thereof by analyzing the discrete degree of the difference in temperature data at all measurement positions between each smelting moment and any short-time smelting moment thereof; determining the smelting effectiveness of each smelting moment by analyzing the difference in adjacent temperature difference consistency between each smelting moment and all short-time smelting moments, and the average distribution of the temperature difference consistency between the current smelting moment and all short-time smelting moments; S203: determining the smelting refinement value at each smelting moment by analyzing the change and discreteness of the temperature data at all measurement positions at each smelting moment and combining the smelting effectiveness; S204: Based on the smelting refinement value, regulating the smelting temperature at the current smelting moment; S3: removing scum from the molten liquid to obtain slag-free zinc alloy liquid; S4: pouring the slag-free zinc alloy liquid into a die-casting mold for die-casting, and performing annealing treatment to obtain a zinc alloy die-casting; S5: grinding, polishing and washing the zinc alloy die-casting to obtain the zinc alloy die-casting after surface treatment; S6: performing laser treatment on the surface-treated zinc alloy die-casting to obtain a laser-treated zinc alloy die-casting; S7: Rinse and dry the laser-treated zinc alloy casting to obtain a high-quality zinc alloy die-casting.

2. A smelting process for high-quality zinc alloy die castings as claimed in claim 1, characterized in that: The production raw materials include: 95.3-96.4 parts of metal zinc, 3.5-4.5 parts of metal aluminum, 0.03-0.05 parts of metal magnesium, 0.1-0.2 parts of metal copper, and 0.32-0.4 parts of aluminum-titanium-boron master alloy.

3. A smelting process for high-quality zinc alloy die castings as claimed in claim 1, characterized in that: During the smelting process, the initial smelting temperature is controlled at 415-420° C., and the electromagnetic stirring time is 15-20 minutes.

4. A smelting process for high-quality zinc alloy die castings as claimed in claim 1, characterized in that: The method for determining the consistency of the temperature difference between each smelting moment and any short-term smelting moment is: The difference between the temperature data at the same measurement position at each melting moment and any short-time melting moment is recorded as the temperature time series difference at the same measurement position between each melting moment and any short-time melting moment; The discrete degree of the temperature time series difference at all measurement positions between each melting moment and any short melting moment thereof is recorded as the discrete temperature difference between each melting moment and any short melting moment thereof; The temperature difference consistency R between the melting time j and its tth short melting time j,t The expression is: R j,t =exp(-σ j,t );where σ j,t represents the discrete temperature difference between the melting time j and its tth short-term melting time; exp() represents an exponential function with a natural constant as the base.

5. A smelting process for high-quality zinc alloy die castings as claimed in claim 1, characterized in that: The expression of the smelting effectiveness at each smelting moment is: In the formula, G j Represents the smelting effectiveness at smelting time j; R j,t , R j,t-1 They represent the consistency of the temperature difference between the melting moment j and its tth and t-1th short-term melting moments respectively; represents the mean value of the temperature difference consistency between melting time j and all its short melting times; T j represents the number of all short-term melting moments at melting moment j; exp() represents an exponential function with a natural constant as the base.

6. A smelting process for high-quality zinc alloy die castings as claimed in claim 1, characterized in that: The method for determining the smelting refinement value at each smelting moment is: Obtain the first-order difference sequence of temperature data at all measurement positions at each melting time, calculate the mean of the absolute values ​​of all elements in the first-order difference sequence, and record it as the mean temperature difference at each melting time; The degree of dispersion of the temperature data at all measurement positions at each melting moment is recorded as the temperature dispersion at each melting moment; The product of the mean temperature difference and the temperature dispersion at each smelting moment is calculated, and the normalized value of the ratio of the product to the smelting effectiveness is used as the smelting refinement value at each smelting moment.

7. A smelting process for high-quality zinc alloy die castings as claimed in claim 1, characterized in that: The regulating and controlling the smelting temperature at the current smelting moment includes: The smelting refinement values ​​of all smelting moments within a preset time period before the current smelting moment are used as inputs of the threshold segmentation algorithm, and the segmentation threshold is output as the adjustment judgment coefficient of the current smelting moment; Based on the difference between the average distribution of the smelting refinement values ​​of all smelting moments within the preset time before the current smelting moment and the adjustment judgment coefficient, and combined with the average distribution of the temperature data at all measurement positions at the previous adjacent moment of the current capacity moment, the smelting feedback temperature at the current moment is determined. The expression of the smelting feedback temperature D at the current moment is: Where De represents the mean value of the temperature data at all measurement locations at the previous melting time of the current melting time; It represents the average value of the smelting refinement values ​​of all short-term smelting moments within the preset time before the current smelting moment; μ represents the adjustment judgment coefficient of the current smelting moment; Dc represents the preset adjustable temperature; The current melting temperature is adjusted to the current melting feedback temperature.

8. A smelting process for high-quality zinc alloy die castings as claimed in claim 1, characterized in that: The sandpaper used in the S5 grinding process is one of the 240, 800, and 1200 sandpapers.

9. A smelting process for high-quality zinc alloy die castings as claimed in claim 1, characterized in that: During the laser treatment process, the laser power is 30-40 kW, the current is 100-200 A, the pulse width is 1-2 mm, and the defocusing amount is 50-60 mm.

10. A smelting process for high-quality zinc alloy die castings as claimed in claim 1, characterized in that: The rinsing solution during the S7 rinsing process is plasma ionized water.

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