A smelting process for high-quality zinc alloy die castings

Abstract

The present application relates to the technical field of zinc structural functional material preparation, and more specifically to a smelting process for high-quality zinc alloy die-castings. The process comprises: preparing raw materials for zinc alloy castings by weight, degreasing, cleaning, and drying the raw materials in sequence to obtain clean raw materials; smelting the clean raw materials in a graphite crucible to obtain a molten liquid; removing scum from the molten liquid to obtain a slag-free zinc alloy liquid; pouring the slag-free zinc alloy liquid into a die-casting mold for die-casting, and annealing to obtain a zinc alloy die-casting; polishing and rinsing the zinc alloy die-casting to obtain a surface-treated zinc alloy die-casting; laser treating the surface-treated zinc alloy die-casting to obtain a laser-treated zinc alloy die-casting; and rinsing and drying the laser-treated zinc alloy die-casting to obtain a high-quality zinc alloy die-casting. The present application improves the toughness of zinc alloy die-castings by controlling the smelting temperature.

Description

Technical Field

[0001] The present application relates to the technical field of preparation of zinc structural functional materials, and in particular to a smelting process for high-quality zinc alloy die-castings. Background Art

[0002] 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 the zinc alloy die-castings. Accurately controlling and adjusting the smelting temperature during the smelting process will help to uniformly distribute the alloy elements and refine the alloy structure during the smelting process. This is the key to improving the toughness of zinc alloy die-castings.

[0003] During the smelting process of zinc alloy die-castings, existing technologies mostly directly control the smelting temperature within a narrow range to avoid the adverse effects of excessively high or low smelting temperatures. However, this method lacks in-depth analysis of the relationship between the alloy liquid temperature and the heat treatment of the alloying elements, making it impossible to accurately control and adjust the smelting temperature during the smelting process. This makes it impossible to meet the smelting temperature requirements of the alloying elements at different smelting times, easily leading to uneven distribution of alloying elements during the smelting process and poor alloy microstructure refinement, ultimately having a significant adverse impact on the toughness of the zinc alloy die-castings. Summary of the Invention

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

[0005] The smelting process of a high-quality zinc alloy die-casting in this application adopts the following technical solution:

[0006] S1: preparing raw materials for zinc alloy castings by weight, and sequentially degreasing, cleaning, and drying the raw materials to obtain clean raw materials;

[0007] S2: The clean raw materials are melted in a graphite crucible to obtain a melt, wherein the melting temperature is controlled. The specific process is as follows:

[0008] 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 moment;

[0009] S202: A preset number of collection moments before each melting moment are used as short-term melting moments for each melting moment; the temperature difference consistency between each melting moment and any of its short-term melting moments is determined by analyzing the degree of dispersion of the temperature data at all measurement locations between each melting moment and any of its short-term melting moments; and the melting effectiveness of each melting moment is determined by analyzing the difference in adjacent temperature difference consistency between each melting moment and all of its short-term melting moments, as well as the average distribution of the temperature difference consistency between the current melting moment and all of its short-term melting moments.

[0010] S203: determining the smelting refinement value at each smelting moment by analyzing the change and dispersion of the temperature data at all measurement positions at each smelting moment and combining the smelting effectiveness;

[0011] S204: regulating the smelting temperature at the current smelting moment based on the smelting refinement value;

[0012] S3: removing slag from the melt to obtain slag-free zinc alloy liquid;

[0013] 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;

[0014] S5: grinding, polishing and rinsing the zinc alloy die-casting to obtain a surface-treated zinc alloy die-casting;

[0015] S6: performing laser treatment on the surface-treated zinc alloy die-casting to obtain a laser-treated zinc alloy die-casting;

[0016] S7: Rinse and dry the laser-treated zinc alloy casting to obtain a high-quality zinc alloy die-casting.

[0017] Preferably, the production raw materials include: 95.3 to 96.4 parts of metallic zinc, 3.5 to 4.5 parts of metallic aluminum, 0.03 to 0.05 parts of metallic magnesium, 0.1 to 0.2 parts of metallic copper, and 0.32 to 0.4 parts of an aluminum-titanium-boron 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 minutes.

[0019] Preferably, the method for determining the consistency of the temperature difference between each melting moment and any short melting moment thereof is:

[0020] The difference between the temperature data at the same measurement position at each melting moment and any short-term melting moment is recorded as the temperature time series difference at the same measurement position between each melting moment and any short-term melting moment;

[0021] The discrete degree of the temperature time series difference between each melting moment and any short melting moment at all measurement positions is recorded as the discrete temperature difference between each melting moment and any short melting moment;

[0022] 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 melting time j and its t-th short melting time; exp() represents the exponential function with natural constant as base.

[0023] Preferably, the expression of the smelting effectiveness at each smelting moment is: Where G j Indicates 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 t-th and t-1 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 melting moments at melting moment j; exp() represents an exponential function with a natural constant as the base.

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

[0025] Obtain the first-order difference sequence of temperature data at all measurement positions at each melting moment, 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 moment;

[0026] 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;

[0027] The product of the mean temperature difference and the temperature dispersion at each melting moment is calculated, and the normalized value of the ratio of the product to the melting effectiveness is used as the melting refinement value at each melting moment.

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

[0029] The smelting refinement values ​​of all smelting moments within a preset time period before the current smelting moment are used as input to the threshold segmentation algorithm, and the segmentation threshold is output as the adjustment judgment coefficient of the current smelting moment;

[0030] Based on the average distribution of the smelting refinement values ​​at all smelting moments within a preset time period before the current smelting moment and the difference in 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 moment of the current melting moment; It represents the average value of the smelting refinement values ​​of all short-term smelting moments within the preset time period before the current smelting moment; μ represents the adjustment judgment coefficient of the current smelting moment; Dc represents the preset adjustable temperature;

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

[0032] Preferably, the sandpaper used in the S5 grinding process is one of 240, 800, and 1200 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 defocusing amount is 50-60 mm.

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

[0035] One embodiment of the present application provides a smelting process for high-quality zinc alloy die castings, the process comprising the following steps:

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

[0037] The present application analyzes the consistency of the difference in alloy liquid temperature between different times at the same measurement position during the smelting process to obtain the temperature difference consistency of the alloy liquid between different smelting moments, and combines the fluctuation and average level of the temperature difference consistency to analyze the effective effect of heat treatment of alloy elements in the smelting process to obtain the smelting effectiveness, which can reflect the effectiveness of heat treatment of alloy elements in the smelting process and judge the uniformity of alloy element distribution, thereby guiding the regulation of smelting temperature, so that alloy elements are better dissolved and diffused in the molten liquid and evenly distributed; further, combined with the smelting The effectiveness and the uneven temperature distribution characteristics in the alloy liquid during the smelting process are used to accurately measure the refinement effect of the alloy elements in the graphite crucible during smelting, and the smelting refinement value is obtained, which is used to more accurately control and adjust the smelting temperature in the graphite crucible in the future; further, the average level of the smelting refinement value in a short period of time before the current smelting moment is used to more accurately feedback and adjust the smelting temperature, so as to meet the requirements of the alloy elements on the smelting temperature at different smelting moments, so that the distribution of the alloy elements in the smelting process is more uniform and the refinement treatment of the alloy structure is more effective, thereby improving the toughness of the zinc alloy die-casting. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the technical solutions and advantages of the embodiments of the present application or the prior art, the following is a brief introduction to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0039] Figure 1 A flowchart of a smelting process for high-quality zinc alloy die-castings provided in one embodiment of the present application;

[0040] Figure 2 A schematic diagram of the temperature control process for zinc alloy smelting provided in one embodiment of the present application. DETAILED DESCRIPTION

[0041] To further illustrate the technical means and effectiveness of this application to achieve its intended purpose, the following, in conjunction with the accompanying drawings and preferred embodiments, details the specific implementation, structure, features, and effectiveness of a smelting process for high-quality zinc alloy die-castings proposed in this application. In the following description, references to different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics of one or more embodiments may be combined in any suitable manner.

[0042] Unless otherwise defined, terms such as "comprises", "includes" or any other variations thereof are intended to cover non-exclusive inclusion, so that a circuit structure, article or device comprising a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such article or device. In the absence of further restrictions, an element defined by the sentence "comprising a ..." does not exclude the presence of additional identical elements in the article or device comprising the element. In addition, the term "and\or" used herein includes any and all combinations of one or more related listed items. All technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs. The following detailed description of the specific scheme of the smelting process of a high-quality zinc alloy die-casting provided in this application is given in conjunction with the accompanying drawings.

[0043] The specific scheme of the smelting process of a high-quality zinc alloy die-casting provided by the present application is described in detail below with reference to the accompanying drawings.

[0044] Example 1

[0045] Example 1 provides a smelting process for high-quality zinc alloy die castings. Figure 1 , the process comprises the following steps:

[0046] S1: preparing raw materials for zinc alloy castings by weight, and sequentially degreasing, cleaning, and drying the raw materials to obtain clean metal raw materials.

[0047] Preparation of production raw materials: Prepare the production raw materials of zinc alloy die-castings by weight. In this embodiment, 95.3 parts of metallic zinc, 3.5 parts of metallic aluminum, 0.03 parts of metallic magnesium, 0.1 parts of metallic copper, and 0.32 parts of aluminum-titanium-boron master alloy are used as the production raw materials of zinc alloy die-castings to produce high-quality zinc alloy die-castings.

[0048] Degreasing, cleaning and drying treatment: The above-mentioned raw materials are placed in an ultrasonic degreasing device for degreasing treatment. Furthermore, the degreasing raw materials are cleaned with ethanol and dried to obtain clean raw materials. The clean raw materials are divided into two categories, namely clean metal raw materials and clean aluminum-titanium-boron intermediate alloy raw materials.

[0049] S2: The clean raw materials are melted 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 and cover them on top of the nickel-based soft magnetic alloy chips.

[0051] Melting treatment: Turn on the heating device to melt the raw materials in the graphite crucible. In this embodiment, the initial melting temperature is selected as 415°C. After the raw materials in the graphite crucible are fully melted, the clean aluminum-titanium-boron intermediate alloy raw materials are slowly added to the alloy liquid. While maintaining the heating condition, turn on the electromagnetic stirrer for stirring. In this embodiment, the electromagnetic stirring time is set to 15 minutes. Then, after the alloy raw materials in the graphite crucible are fully melted, a molten liquid is obtained.

[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 the zinc alloy die-castings. Accurately controlling and adjusting the smelting temperature during the smelting process is conducive to the uniform distribution of alloy elements and the refinement of alloy structure during the smelting process. This is the key to improving the toughness of zinc alloy die-castings. Therefore, based on the temperature changes at different depths of the alloy liquid at the same smelting time, as well as the temperature differences between different smelting times, the smelting temperature during the smelting process is controlled. The specific process is as follows:

[0053] 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 moment.

[0054] During the smelting process of the zinc alloy die-casting, K measurement positions are evenly selected from the alloy liquid in the graphite crucible and the K measurement positions are numbered. The temperature data at the K measurement positions at each smelting moment during the smelting process are measured by a thermocouple temperature sensor. In this embodiment, the measurement time interval is 5 seconds, and the number of measurement positions K is 16. The implementer can set the measurement time interval and the number of measurement positions according to actual conditions, and this embodiment does not impose any special number restrictions.

[0055] S202: A preset number of collection moments before each melting moment are used as the short-term melting moments of each melting moment; the temperature difference consistency between each melting moment and any of its short-term melting moments is determined by analyzing the degree of dispersion of the difference in temperature data at all measurement locations between each melting moment and any of its short-term melting moments; and the melting effectiveness of each melting moment is determined by analyzing the difference in adjacent temperature difference consistency between each melting moment and all short-term melting moments, as well as the average distribution of the temperature difference consistency between the current melting moment and all short-term melting moments.

[0056] During the smelting process of alloying elements in a graphite crucible, the temperature uniformity of the alloy liquid is greatly affected by the heat transfer in the graphite crucible. If there is a large temperature difference at different positions in the alloy liquid, it will, to a certain extent, reflect the uneven distribution of alloying elements in the alloy liquid. The more uneven the distribution of alloying elements in the alloy liquid, the more it can reflect the poor alloying element refinement effect in the alloy liquid. However, in the early stage of smelting the alloying elements, the characteristics of temperature unevenness and alloying element distribution unevenness will generally be more obvious. Measuring the alloying element refinement characteristics based solely on the temperature unevenness characteristics at a certain moment in the alloy liquid will have a large error, which will affect the accuracy of the subsequent control and adjustment of the melting temperature. Therefore, in order to more accurately control and adjust the melting temperature, it is necessary to more accurately analyze the refinement characteristics of the alloying elements during the melting process.

[0057] In order to analyze the smelting characteristics of alloy elements in a short time, the time interval between each smelting moment and all other smelting moments is calculated, and the first preset number of smelting moments in the result of the time interval is arranged in ascending order as the short smelting time 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. The implementer can also set it by himself according to the specific situation. This embodiment does not impose any special restrictions.

[0059] Furthermore, the difference between the temperature data at the same measurement position at each melting moment and any of its short-term melting moments is recorded as the temperature time series difference at the same measurement position between each melting moment and any of its short-term melting moments;

[0060] The degree of discreteness of the temperature time series differences 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 smaller the discrete temperature difference, the higher the consistency of the temperature distribution difference, and the better the effect of melting the alloy elements in the graphite crucible at this time, which can make the melting temperature in the alloy liquid show a more uniform change.

[0061] It should be understood that there are many methods for measuring the difference between data. In this embodiment, the absolute value of the difference between the temperature data at the same measurement position at each melting moment and any other moment is used as the difference between the temperature data at the same measurement position at each melting moment and any other moment, that is, the temperature time series difference at the same measurement position between each melting moment and any other short-term melting moment. In actual application, as other implementation methods, implementers may also use other methods for measuring the difference between data, such as ratios. This embodiment does not impose any special restrictions on the selection of methods for measuring the difference between data.

[0062] It should be noted that there are many methods for measuring the degree of data dispersion. In this embodiment, the dispersion coefficient of the difference between all measurement positions at each melting moment and any short-term melting moment is used as the dispersion degree of the difference between all measurement positions at each melting moment and any short-term melting moment, that is, the discrete temperature difference value. In actual application, as other implementation methods, implementers may also use other methods for measuring the degree of data dispersion, such as variance and standard deviation. This embodiment does not impose any special restrictions on the selection of methods for measuring the degree of data dispersion.

[0063] The calculation method of the dispersion coefficient is a well-known technology, and its specific calculation process will not be repeated here.

[0064] Furthermore, based on the discrete temperature difference values, the consistency of the temperature difference between each melting moment and any short melting moment is determined. The specific expression is:

[0065] 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 melting time j and its t-th short melting time; exp() represents the exponential function with natural constant as base.

[0066] According to the temperature difference consistency between each melting moment and any short melting moment thereof, it can be understood that the discrete temperature difference value is inversely proportional to the temperature difference consistency. The temperature difference consistency reflects the consistency of the temperature distribution difference on the alloy liquid between different melting moments. If the discrete temperature difference value between the current melting moment and its short melting moment is smaller, the temperature difference consistency is greater, indicating that the effect of melting the alloy elements in the graphite crucible at this time is better, and the melting temperature in the alloy liquid can show a more uniform change; conversely, if the discrete temperature difference value between the current melting moment and its short melting moment is larger, the temperature difference consistency is smaller, indicating that the effect of melting the alloy elements in the graphite crucible at this time is worse.

[0067] If the fluctuation of temperature difference consistency in a short period of time is smaller and the average level of temperature difference consistency is higher, it can better reflect the effective effect of heat treatment on alloy elements in the smelting process, and can more prominently illustrate the refinement characteristics of alloy elements in the graphite crucible during the smelting process, which is conducive to more accurate control and adjustment of the smelting temperature in the graphite crucible in the subsequent process.

[0068] Furthermore, the smelting effectiveness at each smelting moment in the smelting process is calculated, specifically:

[0069] The expression of smelting effectiveness at smelting time j is: Where G jIndicates 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 t-th and t-1 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 melting moments at melting moment j; exp() represents an exponential function with a natural constant as the base.

[0070] According to the smelting effectiveness at each smelting moment, it can be understood that the smelting effectiveness reflects the effectiveness of the heat treatment of the alloying elements during the smelting process. If the difference between the t-th and t-1 temperature difference consistency is smaller, the average value of the temperature difference consistency is larger, and the smelting effectiveness is greater, indicating that the effectiveness of the heat treatment of the alloying elements is higher, indicating that the effect of refining the alloying elements in the graphite crucible is better at this time, which is more conducive to the dissolution and diffusion of the alloying elements in the graphite crucible, avoiding the uneven internal structure of the produced zinc alloy die-casting, thereby improving the toughness index of the zinc alloy die-casting;

[0071] On the contrary, if the difference between the t-th and t-1-th temperature difference consistency is larger, the smaller the average value of the temperature difference consistency is, and the smaller the smelting effectiveness is, the lower the effectiveness of the heat treatment of the alloy elements is, indicating that the effect of refining the alloy elements in the graphite crucible is worse, and it is less conducive to the dissolution and diffusion of the alloy elements in the graphite crucible.

[0072] S203: determining the smelting refinement value at each smelting moment by analyzing the change and dispersion of the temperature data at all measurement positions at each smelting moment and combining the smelting effectiveness.

[0073] At the same time, if the temperature non-uniformity of the alloy liquid in the graphite crucible at a certain smelting moment is higher, it means to a certain extent that the distribution uniformity of the alloy elements in the alloy liquid is worse, which is less conducive to the refinement of the alloy elements in the alloy liquid.

[0074] In order to more accurately analyze the refinement characteristics of alloy elements during the smelting process, the first-order difference sequence of temperature data at all measurement positions at each smelting moment is obtained, and the mean of the absolute values ​​of all elements in the first-order difference sequence is calculated and recorded as the mean temperature difference at each smelting moment;

[0075] Furthermore, 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;

[0076] The product of the mean temperature difference and the temperature dispersion at each melting moment is calculated, and the normalized value of the ratio of the product to the melting effectiveness is used as the melting refinement value at each melting moment.

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

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

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

[0080] If the average level of the melting refinement value in the short time before the current melting moment is lower, the melting temperature in the graphite crucible should be appropriately increased to improve the solubility and diffusion capacity of the alloy elements, so as to maintain a better alloy element refinement effect during the melting process; conversely, if the average level of the melting refinement value in the short time before the current melting moment is higher, the alloy raw materials in the graphite crucible are closer to being fully melted into alloy liquid. At this time, the melting temperature in the graphite crucible should be appropriately lowered to avoid burning the beneficial elements in the alloy liquid, increasing zinc slag and reducing the purity of the alloy liquid.

[0081] Furthermore, the smelting refinement values ​​of all smelting moments within a preset time period before the current smelting moment are used as inputs of a threshold segmentation algorithm, and a segmentation threshold is output as an adjustment judgment coefficient for the current smelting moment;

[0082] It should be noted that the value of the preset time length is set manually. In this embodiment, the value of the preset time length is 1 minute. The implementer can also set it by himself according to the specific situation. This embodiment does not impose any special restrictions.

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

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

[0085] The expression of the smelting feedback temperature D at the current smelting moment is: Where De represents the mean value of the temperature data at all measurement locations at the previous melting moment of the current melting moment; It represents the average value of the smelting refinement values ​​of all smelting moments within the preset time period before the current smelting moment; μ represents the adjustment judgment coefficient of the current smelting moment; Dc represents the preset adjustable temperature;

[0086] The melting temperature at the current melting moment in the melting process is adjusted to the melting feedback temperature at the current moment. In this embodiment, the melting temperature in the graphite crucible is adjusted every 2 minutes. The implementer can also set the interval time of temperature adjustment according to the specific situation. This embodiment does not impose any special restrictions.

[0087] It should be noted that the value of the preset adjustable temperature is set artificially, the purpose of which is to limit the range of change of the adjustment temperature and avoid burning of alloy elements during the smelting process due to excessive adjustment of the 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 smelting temperature control process provided in this embodiment is as follows Figure 2 shown.

[0089] At this point, the smelting temperature during the smelting process is controlled to complete the smelting of the alloy liquid and obtain a molten liquid.

[0090] S3: Remove the slag from the molten liquid to obtain a slag-free zinc alloy liquid.

[0091] The scum is removed from the molten liquid after smelting and stirred, and the remaining scum is removed again to obtain a scum-free zinc alloy liquid.

[0092] 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.

[0093] Die casting: The slag-free zinc alloy liquid is introduced into the die casting mold for die casting, and then cooled to room temperature at room temperature to obtain the zinc alloy die casting blank.

[0094] Homogenizing annealing treatment: The zinc alloy die casting blank is subjected to homogenizing annealing treatment to make the alloy elements evenly distributed throughout the zinc alloy die casting to obtain the zinc alloy die casting.

[0095] S5: Grinding, polishing and rinsing the zinc alloy die-casting to obtain the surface-treated zinc alloy die-casting.

[0096] The surface of the zinc alloy die-casting is polished with sandpaper and then rinsed. In this embodiment, 240-grit sandpaper is used to polish the zinc alloy die-casting step by step during the polishing process to obtain a zinc alloy die-casting after surface treatment.

[0097] S6: performing laser treatment on the surface-treated zinc alloy die-casting to obtain a laser-treated zinc alloy die-casting.

[0098] The surface-treated zinc alloy die-casting is laser treated, wherein 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 properties of the zinc alloy die-casting and obtain the laser-treated zinc alloy die-casting.

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

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

[0101] Example 2

[0102] Example 2 provides a smelting process for high-quality zinc alloy die castings. Figure 1 , the process comprises the following steps:

[0103] S1: preparing raw materials for zinc alloy castings by weight, and sequentially degreasing, cleaning, and drying the raw materials to obtain clean metal raw materials.

[0104] Preparation of production raw materials: Prepare the production raw materials of zinc alloy die-castings 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 of zinc alloy die-castings to produce high-quality zinc alloy die-castings.

[0105] The operations of degreasing, cleaning and drying the raw materials are carried out in the same manner as in Example 1.

[0106] S2: The clean raw materials are melted in a graphite crucible to obtain a molten liquid.

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

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

[0109] 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.

[0110] S5: Grinding, polishing and rinsing the zinc alloy die-casting to obtain a surface-treated zinc alloy die-casting. In this embodiment, 800-grit sandpaper is used to grind and polish the zinc alloy die-casting step by step during the grinding process. The remaining operations are the same as those in Example 1.

[0111] S6: performing laser treatment on the surface-treated zinc alloy die-casting to obtain a laser-treated zinc alloy die-casting.

[0112] The surface-treated zinc alloy die-casting is laser treated, wherein 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 properties of the zinc alloy die-casting and obtain the laser-treated zinc alloy die-casting.

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

[0114] Example 3

[0115] Example 3 provides a smelting process for high-quality zinc alloy die castings. Figure 1 , the process comprises the following steps:

[0116] S1: preparing raw materials for zinc alloy castings by weight, and sequentially degreasing, cleaning, and drying the raw materials to obtain clean metal raw materials.

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

[0118] The operations of degreasing, cleaning and drying the raw materials are carried out in the same manner as in Example 1.

[0119] S2: The clean raw materials are melted in a graphite crucible to obtain a molten liquid.

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

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

[0122] 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.

[0123] S5: Grinding, polishing and rinsing the zinc alloy die-casting to obtain a surface-treated zinc alloy die-casting. In this embodiment, 1200-grit sandpaper is used to grind and polish the zinc alloy die-casting step by step during the grinding process. The remaining operations are the same as those in Example 1.

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

[0125] The surface-treated zinc alloy die-casting is laser treated, wherein 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 properties of the zinc alloy die-casting and obtain the laser-treated zinc alloy die-casting.

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

[0127] Comparison of Examples

[0128] In order to verify the validity of the parameters of this application, this application sets up several comparative examples, specifically:

[0129] Comparative Example 1: The smelting process temperature was always controlled at 415°C, and the remaining operations were the same as in Example 1;

[0130] Comparative Example 2: The smelting process temperature was always controlled at 418°C, and the remaining operations were the same as in Example 2;

[0131] Comparative Example 3: The smelting process temperature was always controlled at 420°C, and the remaining operations were the same as in Example 3;

[0132] Physical property tests were performed on the zinc alloy die-castings in the embodiment and the comparative example. The performance test indicators included density, compressive strength, tensile strength, elongation, and impact toughness. The toughness evaluation indicators were elongation and impact toughness. The performance comparison results of the zinc alloy die-castings in the embodiment and the comparative example are shown in Table 1:

[0133] Table 1 Comparison of zinc alloy properties

[0134]

[0135] It should be noted that the order in which the embodiments of the present application are presented is for illustrative purposes only and does not necessarily represent the superiority or inferiority of the embodiments. Furthermore, the foregoing descriptions of specific embodiments of this specification are provided. Furthermore, the processes depicted in the accompanying drawings do not necessarily require the specific order or sequential sequence shown to achieve the desired results. In certain embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0136] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referred 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 not to limit them. Modifications to the technical solutions described in the aforementioned embodiments, or equivalent replacements of some of the technical features therein, do 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 should all be included in the scope of protection 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 sequentially degreasing, cleaning, and drying the raw materials to obtain clean raw materials; S2: The clean raw materials are melted in a graphite crucible to obtain a melt, 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 moment; S202: A preset number of collection moments before each melting moment are used as short-term melting moments for each melting moment; the temperature difference consistency between each melting moment and any of its short-term melting moments is determined by analyzing the degree of dispersion of the temperature data at all measurement locations between each melting moment and any of its short-term melting moments; and the melting effectiveness of each melting moment is determined by analyzing the difference in adjacent temperature difference consistency between each melting moment and all of its short-term melting moments, as well as the average distribution of the temperature difference consistency between the current melting moment and all of its short-term melting moments. S203: determining the smelting refinement value at each smelting moment by analyzing the change and dispersion of the temperature data at all measurement positions at each smelting moment and combining the smelting effectiveness; S204: regulating the smelting temperature at the current smelting moment based on the smelting refinement value; S3: removing slag from the melt 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 rinsing the zinc alloy die-casting to obtain a surface-treated zinc alloy die-casting; S6: performing laser treatment on the surface-treated zinc alloy die-casting to obtain a laser-treated zinc alloy die-casting; S7: rinsing and drying the laser-treated zinc alloy casting to obtain high-quality zinc alloy die-castings; 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, and 0.32-0.4 parts of aluminum-titanium-boron master alloy; The expression of the smelting effectiveness at each smelting moment is: Where, Indicates the smelting effectiveness at smelting time j; 、 They represent the consistency of the temperature difference between the melting moment j and its t-th and t-1 short-term melting moments respectively; It represents the mean value of the temperature difference consistency between melting time j and all its short melting times; represents the number of all short melting moments at melting moment j; exp( ) represents an exponential function with a natural constant as the base; The regulating and controlling of 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 input to the threshold segmentation algorithm, and the segmentation threshold is output as the adjustment judgment coefficient of the current smelting moment; Based on the average distribution of the smelting refinement values ​​at all smelting moments within a preset time period before the current smelting moment and the difference in 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, Indicates the mean value of the temperature data at all measurement locations at the previous melting moment of the current melting moment; Indicates the average of the smelting refinement values ​​of all short smelting moments within the preset time period before the current smelting moment; Indicates the adjustment judgment coefficient of the current smelting moment; Indicates preset adjustable temperature; Adjust the current melting temperature to the current melting feedback temperature.

2. 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.

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

4. 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 moment, 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 moment; 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 melting moment is calculated, and the normalized value of the ratio of the product to the melting effectiveness is used as the melting refinement value at each melting moment.

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

6. 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.

7. The smelting process for high-quality zinc alloy die castings according to claim 1, characterized in that: The rinsing solution during the S7 rinsing process is plasma water.

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