System and method for synthesizing cast iron material through silicon carbide pre-inoculation

Abstract

The invention relates to the technical field of cast iron materials, in particular to a silicon carbide pre-inoculation synthetic cast iron material system, which comprises a smelting module, a pre-inoculation module, a silicon carbide pre-inoculation module, a silicon carbide pre-inoculation module and a silicon carbide pre-inoculation module, the inoculation module is connected with the smelting module and comprises a first inoculation device and a second inoculation device; the detection module is connected with the smelting module and the inoculation module and used for monitoring the carbon equivalent in the smelting process in real time, collecting a plurality of metallographic samples at different point positions on the casting and conducting metallographic analysis to obtain the graphite form characteristic value and the white body content. And the control module is connected with the smelting module, the inoculation module and the detection module and used for dynamically adjusting the input amount of silicon carbide according to the real-time carbon equivalent in the smelting process and judging the inoculation qualification according to the graphite form characteristic value. The intelligent level and the quality controllability of cast iron production are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of cast iron materials, and particularly relates to a silicon carbide pre-inoculation synthetic cast iron material system and method. BACKGROUND

[0002] Gray cast iron occupies an important position in the field of machine tool manufacturing due to its good casting performance, mechanical properties and cost advantage. With the increasing requirements of modern industry on the precision and stability of machine tools, traditional gray cast iron materials are difficult to meet the needs of high-end machine tool parts for strength and wear resistance. Silicon carbide has been used as a cast iron pretreatment agent, which can provide non-equilibrium graphite as the core, promote the formation of A-type graphite, increase the number of eutectic groups, and reduce the tendency of chill. Silicon carbide decomposes in molten iron to produce highly active carbon atoms, which can effectively act as a graphite nucleation substrate, and also has the effects of deoxidizing and purifying molten iron.

[0003] Although gray cast iron adopts silicon carbide pretreatment technology, it still has the following disadvantages and limitations: SiC needs to be fully decomposed at high temperature, if the temperature of the molten iron is insufficient or the time is not enough, it may cause residual un-melted silicon carbide particles, forming hard spots, affecting the machining performance or causing casting defects; the decomposition of silicon carbide will simultaneously increase silicon and carbon, if the original molten iron silicon is already high, it may cause the final silicon to exceed the standard, reduce the proportion of pearlite, and weaken the strength; the carbon and silicon contributions of silicon carbide need to be accurately calculated to avoid excessive carbon equivalent causing graphite coarsening or shrinkage defects, etc.

[0004] Chinese patent application publication No. CN117385267A discloses an inoculant material for gray cast iron; graphite material is used as the core body, quartz SiO2 and graphite mixture are heated by electricity to generate silicon carbide; then crushed to the required particle size range; the crushed silicon carbide is placed in the furnace, then nitrogen gas and ammonia gas are introduced, carbon-nitrogen replacement is carried out at 1400 DEG C, and the sintering time is 6-8 hours, part of the SiC is replaced by SiN; after preparation, crushing to 1-5mm particle size, the inoculant is obtained; the present application only uses ordinary carbon product raw materials for sintering, effectively reduces the production cost, and can greatly achieve the purpose of cost reduction.

[0005] However, the existing technology has the following problems: the existing technology only adds it as a conventional inoculant once before pouring, and does not fully utilize the pretreatment function of silicon carbide in the molten iron smelting process, nor does it build a more stable and powerful nucleation foundation through a phased and multi-level addition strategy, thereby limiting the optimization of graphite morphology and the strength and wear resistance of the material. SUMMARY

[0006] Therefore, the present application provides a silicon carbide pre-inoculation synthetic cast iron material system and method to overcome the problem of insufficient strength and wear resistance of the synthetic cast iron material caused by the lack of control over the inoculation process in the prior art.

[0007] To achieve the above object, the present application provides a silicon carbide pre-inoculation synthetic cast iron material system, comprising: a smelting module comprising a furnace body for smelting first particle size silicon carbide with furnace charge and completing pre-inoculation; an inoculation module connected with the smelting module, comprising a first inoculation device arranged above the furnace body tapping runner for uniformly adding a first inoculant during tapping of molten iron, and a second inoculation device for uniformly adding a second inoculant during pouring of molten iron; a detection module connected with the smelting module and the inoculation module respectively, for real-time monitoring of carbon equivalent in the smelting process, and collecting a plurality of metallographic samples at different points on the casting and performing metallographic analysis to obtain graphite morphology characteristic value and white body content; a control module connected with the smelting module, the inoculation module and the detection module respectively, for dynamically adjusting the input amount of silicon carbide according to the real-time carbon equivalent in the smelting process, for determining the qualification of inoculation according to the graphite morphology characteristic value, and for determining the stage of unqualified inoculation and determining the adjustment strategy according to the white body content under the condition of unqualified inoculation, wherein the adjustment strategy comprises increasing the addition amount of second particle size silicon carbide or increasing the outflow speed of the inoculation device.

[0008] Further, the process of dynamically adjusting the input amount of silicon carbide according to the real-time carbon equivalent in the smelting process by the control module comprises: real-time monitoring of carbon equivalent in the smelting process by a thermal analyzer; comparing the real-time carbon equivalent with a first preset carbon equivalent and a second preset carbon equivalent respectively; if the real-time carbon equivalent is less than the first preset carbon equivalent, then controlling the smelting module to increase the input amount of first particle size silicon carbide; if the real-time carbon equivalent is greater than or equal to the second preset carbon equivalent, then controlling the smelting module to add scrap steel for dilution; until the real-time carbon equivalent stabilizes between the first preset carbon equivalent and the second preset carbon equivalent.

[0009] Further, the process of metallographic analysis comprises: collecting a plurality of metallographic samples from different points on the casting; grinding, polishing and etching treatment of the plurality of metallographic samples; obtaining the graphite morphology characteristic value of the sample by a metallographic microscope combined with an image analysis system; identifying and calculating the area ratio of white body in the metallographic image, denoted as white body content.

[0010] Further, the graphite morphology characteristic value is determined by the average size and uniformity of graphite.

[0011] Further, judging the qualification of the inoculation according to the graphite morphology characteristic value, wherein, If the graphite morphology characteristic value is less than a preset characteristic value, it is determined that the inoculation is unqualified, and the stage of the unqualified inoculation is determined according to the white body content; If the graphite morphology characteristic value is greater than or equal to the preset characteristic value, it is determined that the inoculation is qualified.

[0012] Further, the stage of the unqualified inoculation is determined according to the white body content, wherein, If the white body content is less than a preset content, it is determined that the stage of the unqualified inoculation is a pre-inoculation stage; If the white body content is greater than or equal to the preset content, it is determined that the stage of the unqualified inoculation is a first inoculation stage or a second inoculation stage, and the stage of the unqualified inoculation is further determined according to the position of the white body content exceeding the standard.

[0013] Further, the stage of the unqualified inoculation is further determined according to the position of the white body content exceeding the standard, wherein, If the position of the white body content exceeding the standard is only at the thin wall of the casting, it is determined that the stage of the unqualified inoculation is the second inoculation stage; If the position of the white body content exceeding the standard exists at both the thick wall and the thin wall of the casting, it is determined that the stage of the unqualified inoculation is the first inoculation stage.

[0014] Further, an adjustment strategy is determined based on the stage of the unqualified inoculation, wherein, If the stage of the unqualified inoculation is the pre-inoculation stage, it is determined that the adjustment strategy is to increase the addition amount of the second particle size silicon carbide according to the A-type graphite proportion difference value, wherein the A-type graphite proportion difference value is the difference between the preset percentage of A-type graphite and the measured percentage of A-type graphite; If the stage of the unqualified inoculation is the first inoculation stage or the second inoculation stage, it is determined that the adjustment strategy is to increase the outflow speed of the inoculation device.

[0015] Further, there are several adjustment modes for the addition amount of the second particle size silicon carbide, and each adjustment mode has a different adjustment range for the addition amount of the second particle size silicon carbide.

[0016] The application also provides a method for synthesizing cast iron material by pre-inoculating silicon carbide, comprising: Step S1, adding a furnace charge and first particle size silicon carbide into a furnace body for smelting, wherein the furnace charge includes scrap steel and scrap castings; Step S2, after the smelting temperature reaches a preset temperature, the smelting is stopped for a preset time, and in the smelting process, a thermal analyzer is used to monitor the carbon equivalent in real time, and the input amount of the first particle size silicon carbide is dynamically adjusted to ensure that the carbon equivalent is stable within a preset range; Step S3, after the slagging treatment is completed, second particle size silicon carbide is added to the furnace for pre-inoculation; Step S4, after the pre-inoculation is completed, the molten iron is tapped, and in the tapping process, the first inoculant is uniformly added for primary stream inoculation; Step S5, after the primary stream inoculation is completed, the molten iron is poured, and in the pouring process, the second inoculant is uniformly added for secondary stream inoculation, and the pouring of the casting is completed; Step S6, a plurality of metallographic samples at different points on the casting are collected and metallographic analysis is performed to obtain graphite morphology characteristic values and white body content, the inoculation is judged according to the graphite morphology characteristic values, and under the condition of unqualified, the stage of inoculation unqualified is determined and the adjustment strategy is determined.

[0017] Compared with the prior art, the beneficial effects of the present application are that the present application adopts a silicon carbide staged inoculation strategy, and is combined with a real-time monitoring and closed-loop feedback control system. The system can dynamically adjust the silicon carbide input according to the real-time carbon equivalent in the smelting process, to ensure that the composition of the molten iron is always stable in the best process window. Through the reverse diagnosis of the metallographic analysis results of the final casting, the specific stage of inoculation failure can be accurately located, and the corresponding adjustment strategy is executed accordingly. The production process is realized fine, intelligent and consistent.

[0018] Further, the present application selects silicon carbide as the raw material, which improves the graphitization effect and reduces the cost. Silicon carbide can release high-activity carbon atoms in the molten iron, which serves as an excellent graphite nucleation substrate, greatly increasing the number of graphite cores. This makes the final obtained graphite flakes smaller and more uniform in distribution, effectively reducing the tendency of the molten iron to supercool, thereby reducing the formation of D-type graphite and carbides. This not only directly improves the mechanical strength of the material, but also improves its processing performance.

[0019] Further, in the synthetic cast iron process, silicon carbide can replace part of the traditional carbon additive. Silicon carbide can provide a high-purity carbon source, avoiding the negative impact of residual impurities such as sulfur and phosphorus in traditional carbon additives on the quality of the molten iron. At the same time, the decomposition of silicon carbide can achieve synchronous and balanced increase of silicon and carbon elements, making the adjustment of carbon equivalent more stable and smooth, effectively avoiding the problem of carbon equivalent imbalance caused by excessive silicon alone when using ferrosilicon inoculation. In addition, silicon carbide also has a certain deoxidizing ability, which helps to reduce oxide inclusions in the molten iron, reducing the risk of air holes and slag inclusion in the casting, thereby further improving the density and overall quality of the casting. BRIEF DESCRIPTION OF DRAWINGS

[0020] Fig. 1 It is a module connection schematic diagram of the silicon carbide pre-inoculation synthetic cast iron material system of the embodiment of the present application; Fig. 2A flow chart for determining the qualification of inoculation according to the graphite morphology characteristic value in the embodiment of the present application; Fig. 3 A flow chart for determining the stage of unqualified inoculation in the embodiment of the present application; Fig. 4 A flow chart for the method of synthesizing cast iron material by silicon carbide pre-inoculation in the embodiment of the present application. DETAILED DESCRIPTION

[0021] In order to make the objects and advantages of the present application clearer, the present application will be further described below in conjunction with embodiments; it should be understood that the specific embodiments described herein are only used to explain the present application and not to limit the present application.

[0022] The preferred embodiments of the present application will be described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present application and not to limit the protection scope of the present application.

[0023] It should be pointed out that the data in the present embodiment are obtained by comprehensive analysis and evaluation of historical detection data and corresponding historical detection results in the three months before the present detection by the present application. Those skilled in the art can understand that the determination method of the present application for a single parameter can be to select the value with the highest proportion as the preset standard parameter according to the data distribution, to use weighted summation to obtain the value as the preset standard parameter, to substitute each historical data into a specific formula and to obtain the value by the formula as the preset standard parameter, or other selection methods, as long as the present application can clearly define different specific situations in the single determination process by the obtained value.

[0024] Please refer to Figs. 1 to 4 respectively, a flow chart for determining the qualification of inoculation according to the graphite morphology characteristic value in the embodiment of the present application, a flow chart for determining the stage of unqualified inoculation in the embodiment of the present application, and a flow chart for the method of synthesizing cast iron material by silicon carbide pre-inoculation in the embodiment of the present application.

[0025] The silicon carbide pre-inoculation cast iron material system in the embodiment of the present application comprises: The smelting module comprises a furnace body for smelting the first particle size silicon carbide and the charge and completing pre-inoculation; The inoculation module is connected with the smelting module and comprises a first inoculation device arranged above the furnace outlet flow channel for uniformly adding the first inoculant during the tapping of the molten iron, and a second inoculation device for uniformly adding the second inoculant during the pouring of the molten iron; a detection module connected with the smelting module and the inoculation module respectively, for monitoring the carbon equivalent in the smelting process in real time, and collecting a plurality of metallographic samples at different points on the casting and performing metallographic analysis to obtain the graphite morphology characteristic value and the white body content; a control module connected with the smelting module, the inoculation module and the detection module respectively, for dynamically adjusting the input amount of silicon carbide according to the real-time carbon equivalent in the smelting process, for judging the qualification of inoculation according to the graphite morphology characteristic value, and for determining the stage of unqualified inoculation and determining the adjustment strategy according to the white body content under the condition of unqualified inoculation, wherein the adjustment strategy includes increasing the addition amount of the second particle size silicon carbide or increasing the outflow speed of the inoculation device.

[0026] Specifically, the raw materials include silicon carbide and furnace charge, the first particle size silicon carbide has a particle size of 1-5 mm, and the silicon carbide addition amount accounts for 0.8%-1.2%, the furnace charge includes scrap steel and scrap castings, the scrap steel addition amount accounts for 60%-80%, and the rest is scrap castings of the same material, wherein the scrap castings need to be treated by shot blasting to ensure that the surface is free of rust and sand.

[0027] Specifically, the furnace body is a medium-frequency induction electric furnace, which is provided with an automatic feeding unit for accurately controlling the input amount of the first particle size silicon carbide, the automatic feeding unit is connected with the control module and receives instructions from the control module to dynamically adjust the input amount of silicon carbide.

[0028] Specifically, the first inoculant is a silicon-barium inoculant, which has a particle size of 3-10 mm and accounts for 0.3%-0.5% of the mass of molten iron, and is added for 80% of the iron tapping time.

[0029] Specifically, the second inoculant is a silicon-barium inoculant, which has a particle size of 0.2-0.8 mm and accounts for 0.1%-0.2% of the mass of molten iron, and is added for 80% of the pouring time.

[0030] Specifically, the process in which the control module dynamically adjusts the input amount of silicon carbide according to the real-time carbon equivalent in the smelting process includes: monitoring the carbon equivalent in the smelting process in real time by using a thermal analyzer; comparing the real-time carbon equivalent with the first preset carbon equivalent and the second preset carbon equivalent respectively; if the real-time carbon equivalent is less than the first preset carbon equivalent, then increasing the input amount of the first particle size silicon carbide by the smelting module; if the real-time carbon equivalent is greater than or equal to the second preset carbon equivalent, then adding scrap steel to dilute by the smelting module; until the real-time carbon equivalent is stable between the first preset carbon equivalent and the second preset carbon equivalent.

[0031] In the embodiment of the present application, the first preset carbon equivalent value is 3%, and the second preset carbon equivalent value is 5%.

[0032] Specifically, the process of metallographic analysis includes: Collecting a plurality of metallographic samples from different points of the casting; Grinding, polishing and etching treatment are performed on the plurality of metallographic samples; Obtaining the graphite morphology characteristic value of the sample through a metallographic microscope combined with an image analysis system; Identifying and calculating the area ratio of white body in the metallographic image, which is denoted as white body content.

[0033] Specifically, the different points include the thin wall and the thick wall of the casting, and the number of points is not limited.

[0034] Specifically, the graphite morphology characteristic value is determined by the average size and uniformity of graphite, and the graphite morphology characteristic value = first weight coefficient x size threshold value / average size of graphite + second weight coefficient x uniformity of graphite / uniformity threshold value, wherein the first weight coefficient is 0.6, the size threshold value is 40 μm, the second weight coefficient is 0.4, and the uniformity threshold value is 0.85.

[0035] Specifically, the average size of graphite is the average particle size of graphite particles; the uniformity of graphite represents the regularity of the distribution of graphite particles. The larger the uniformity is, the closer the size of the graphite particles is, and the equal the spacing is, without obvious aggregation or sparse area. The uniformity of graphite is obtained by the area density method, the entire field of view is divided into a plurality of grids, the number of graphite particles in each grid is counted, and then the coefficient of variation (standard deviation / average value) of the number of particles in all grids is calculated.

[0036] Specifically, the eligibility of inoculation is determined according to the graphite morphology characteristic value, wherein, If the graphite morphology characteristic value is less than a preset characteristic value, it is determined that the inoculation is unqualified, and the stage of unqualified inoculation is determined according to the white body content; If the graphite morphology characteristic value is greater than or equal to the preset characteristic value, it is determined that the inoculation is qualified.

[0037] In the embodiment of the present application, the preset characteristic value is 0.8, but the value is not limited thereto, and those skilled in the art can adjust the value according to actual needs.

[0038] Specifically, the stage of unqualified inoculation is determined according to the white body content, wherein, If the white body content is less than a preset content, it is determined that the stage of unqualified inoculation is pre-inoculation stage; If the white body content is greater than or equal to the preset content, it is determined that the stage of unqualified inoculation is the first inoculation stage or the second inoculation stage, and the stage of unqualified inoculation is further determined according to the position of the white body content exceeding the standard.

[0039] In the embodiment of the present application, the preset content is 2%, but the value is not limited to this, and the value can be adjusted according to actual needs by those skilled in the art.

[0040] Specifically, the stage of unqualified inoculation is further determined according to the position of the white body content exceeding the standard, wherein, If the position of the white body content exceeding the standard is only located at the thin wall of the casting, it is determined that the stage of unqualified inoculation is the second inoculation stage; If the position of the white body content exceeding the standard exists at both the thick wall and the thin wall of the casting, it is determined that the stage of unqualified inoculation is the first inoculation stage.

[0041] Specifically, the adjustment strategy is determined based on the stage of unqualified inoculation, wherein, If the stage of unqualified inoculation is the pre-inoculation stage, it is determined that the adjustment strategy is to increase the addition amount of the second particle size silicon carbide according to the A-type graphite proportion difference value, wherein the A-type graphite proportion difference value is the difference between the A-type graphite preset percentage and the A-type graphite measured percentage; If the stage of unqualified inoculation is the first inoculation stage or the second inoculation stage, it is determined that the adjustment strategy is to increase the outflow speed of the inoculation device.

[0042] In the embodiment of the present application, the A-type graphite preset percentage is 85%, but the value is not limited to this, and the value can be adjusted according to actual needs by those skilled in the art.

[0043] Specifically, the addition amount of the second particle size silicon carbide is set to have several adjustment modes, and each adjustment mode has a different adjustment range for the addition amount of the second particle size silicon carbide, wherein if the A-type graphite proportion difference value is less than the preset difference value, the addition amount of the second particle size silicon carbide is determined to be 0.1% of the mass of molten iron; If the A-type graphite proportion difference value is greater than or equal to the preset difference value, the addition amount of the second particle size silicon carbide is determined to be 0.15% of the mass of molten iron.

[0044] In the embodiment of the present application, the preset difference value is 5%, but the value is not limited to this, and the value can be adjusted according to actual needs by those skilled in the art.

[0045] Specifically, the outflow speed of the inoculation device is increased according to the white body content exceeding the standard rate, wherein if the white body content exceeding the standard rate is less than the preset exceeding the standard rate, the outflow speed of the inoculation device is increased to a corresponding value using a first speed adjustment coefficient 1.2; If the white body content exceeds the preset rate, the outflow speed of the inoculation device is increased to a corresponding value using a second speed adjustment coefficient 1.5. White body content exceeds the preset rate = (measured white body content-preset content) / preset content.

[0046] In the embodiment of the present application, the initial outflow speed is not specifically limited, and the preset exceeding rate is 10%, but the value is not limited thereto, and those skilled in the art can adjust the value according to actual needs.

[0047] The method for preparing silicon carbide pre-inoculation synthetic cast iron material in the embodiment of the present application comprises: Step S1, adding the furnace charge and the first particle size silicon carbide into the furnace body for smelting, wherein the furnace charge comprises scrap steel and scrap castings; Step S2, after the smelting temperature reaches the preset temperature, the smelting is stopped for a preset time, and in the smelting process, a thermal analyzer is used to monitor the carbon equivalent in real time, and the input amount of the first particle size silicon carbide is dynamically adjusted to ensure that the carbon equivalent is stable within the preset range; Step S3, after the slag removal treatment is completed, the second particle size silicon carbide is added to the furnace for pre-inoculation; Step S4, after the pre-inoculation is completed, the molten iron is discharged, and in the discharging process, the first inoculant is uniformly added for primary stream inoculation; Step S5, after the primary stream inoculation is completed, the molten iron is poured, and in the pouring process, the second inoculant is uniformly added for secondary stream inoculation, and the pouring of the castings is completed; Step S6, a plurality of metallographic samples at different points on the castings are collected and metallographic analysis is performed to obtain graphite morphology characteristic values and white body content, and the inoculation is determined to be qualified according to the graphite morphology characteristic values, and under the unqualified condition, the stage of unqualified inoculation is determined and the adjustment strategy is determined according to the white body content.

[0048] Specifically, in step S1, the first particle size silicon carbide is added after 40% to 80% of the melting of the furnace charge is completed. If it is added too early, the silicon carbide is easy to lose its role as a pretreatment agent, and can only play the effect of adjusting the chemical composition; if it is added too late, the silicon carbide is difficult to completely dissolve due to insufficient action time, and is easy to form heterogeneous inclusions in the molten iron.

[0049] Specifically, in step S2, the preset temperature is 1500℃, and the preset time range is 3-5 minutes.

[0050] Specifically, in step S3, the particle size of the second particle size silicon carbide is 0.2-1mm, and the addition amount accounts for 0.05%-0.15% of the mass of the molten iron.

[0051] Specifically, the tapping temperature of the molten iron is controlled at 1460℃, and the pouring temperature is maintained between 1400℃ and 1420℃.

[0052] The technical scheme of the present application has been described in combination with the preferred embodiments shown in the drawings, but it is easy for those skilled in the art to understand that the protection scope of the present application is obviously not limited to these specific embodiments. Those skilled in the art can make equivalent changes or replacements to the related technical features without departing from the principles of the present application, and the technical schemes after the changes or replacements will all fall within the protection scope of the present application.

[0053] The above description is only the preferred embodiments of the present application and is not intended to limit the present application; the present application can have various changes and variations for those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A silicon carbide pre-inoculated synthetic cast iron material system, characterized in that, include: The smelting module includes a furnace body for smelting silicon carbide of the first particle size with the furnace charge and completing the pre-inoculation. The inoculation module, which is connected to the smelting module, includes a first inoculation device disposed above the furnace tapping trough for uniformly adding a first inoculator during the tapping process of molten iron, and a second inoculation device for uniformly adding a second inoculator during the pouring process of molten iron. The detection module is connected to the smelting module and the inoculation module respectively, and is used to monitor the carbon equivalent in real time during the smelting process, and to collect several metallographic samples at different points on the casting and perform metallographic analysis to obtain graphite morphology characteristic values ​​and white iron content. The control module, which is connected to the smelting module, the inoculation module, and the detection module, is used to dynamically adjust the amount of silicon carbide added based on the real-time carbon equivalent during the smelting process, to determine the qualification of inoculation based on the graphite morphology characteristics, and, under unqualified conditions, to determine the unqualified stage of inoculation based on the white iron content and to determine the adjustment strategy. The adjustment strategy includes increasing the amount of second-size silicon carbide added or increasing the outflow rate of the inoculation device.

2. The silicon carbide pre-inoculated synthetic cast iron material system according to claim 1, characterized in that, The process by which the control module dynamically adjusts the amount of silicon carbide input based on the real-time carbon equivalent during the smelting process includes: The carbon equivalent during the smelting process was monitored in real time using a thermal analyzer; The real-time carbon equivalent is compared with the first preset carbon equivalent and the second preset carbon equivalent, respectively; If the real-time carbon equivalent is less than the first preset carbon equivalent, the smelting module is controlled to increase the amount of silicon carbide of the first particle size. If the real-time carbon equivalent is greater than or equal to the second preset carbon equivalent, then the smelting module is controlled to add scrap steel for dilution; Until the real-time carbon equivalent stabilizes between the first preset carbon equivalent and the second preset carbon equivalent.

3. The silicon carbide pre-inoculated synthetic cast iron material system according to claim 2, characterized in that, The metallographic analysis process includes: Several metallographic samples were collected from different locations on the casting. Several metallographic samples were ground, polished, and etched. The graphite morphological characteristics of the samples were obtained by using a metallographic microscope combined with an image analysis system. Identify and calculate the area ratio of white iron bodies in the metallographic image, denoted as the white iron body content.

4. The silicon carbide pre-inoculated synthetic cast iron material system according to claim 3, characterized in that, The morphological characteristics of the graphite are determined by the average size and uniformity of the graphite.

5. The silicon carbide pre-inoculated synthetic cast iron material system according to claim 4, characterized in that, The suitability of the incubation process is determined based on the morphological characteristics of graphite. If the graphite morphology characteristic value is less than the preset characteristic value, the incubation is deemed unqualified, and the stage of unqualified incubation is determined according to the white body content. If the graphite morphological characteristic value is greater than or equal to the preset characteristic value, then the incubation is deemed successful.

6. The silicon carbide pre-inoculated synthetic cast iron material system according to claim 5, characterized in that, The stage of development that fails to meet standards is determined based on the content of white body components. If the white body content is less than the preset content, the stage of incubation is determined to be the pre-incubation stage if the incubation is unqualified. If the white body content is greater than or equal to the preset content, the stage of unqualified incubation is determined to be the first incubation stage or the second incubation stage, and the stage of unqualified incubation is further determined according to the location where the white body content exceeds the standard.

7. The silicon carbide pre-inoculated synthetic cast iron material system according to claim 6, characterized in that, The stage of development failure was further determined based on the location of excessive white body content. If the excessive white iron content is only located in the thin-walled part of the casting, then the stage of unqualified inoculation is determined to be the second inoculation stage. If the white iron content exceeds the standard in both the thick and thin walls of the casting, then the stage where the inoculation is deemed unqualified is the first inoculation stage.

8. The silicon carbide pre-inoculated synthetic cast iron material system according to claim 7, characterized in that, Adjustment strategies are determined based on the stage of unsatisfactory development, among which... If the incubation stage is the pre-incubation stage, the adjustment strategy is to increase the amount of second-size silicon carbide added based on the difference in the proportion of type A graphite, wherein the difference in the proportion of type A graphite is the difference between the preset percentage of type A graphite and the measured percentage of type A graphite. If the incubation stage is the first or second incubation stage, the adjustment strategy is to increase the outflow rate of the incubation device.

9. The silicon carbide pre-inoculated synthetic cast iron material system according to claim 8, characterized in that, Several adjustment methods are provided for the amount of silicon carbide with second particle size added, and each adjustment method has a different adjustment range for the amount of silicon carbide with second particle size added.

10. A method for pre-inoculating and synthesizing cast iron materials using silicon carbide, applied to the silicon carbide pre-inoculating and synthesizing cast iron material system according to any one of claims 1-9, characterized in that, include: Step S1: The furnace charge and silicon carbide of the first particle size are added to the furnace body for smelting, wherein the furnace charge includes scrap steel and scrap castings; Step S2: After the melting temperature reaches the preset temperature, let it stand for a preset time. During the melting process, use a thermal analyzer to monitor the carbon equivalent in real time and dynamically adjust the amount of silicon carbide of the first particle size to ensure that the carbon equivalent is stable within the preset range. Step S3: After completing the slag removal process, add silicon carbide of the second particle size into the furnace for pre-inoculation. Step S4: After completing the pre-inoculation, the molten iron is tapped out of the furnace. During the tapping process, the first inoculant is added evenly to carry out one in-flow inoculation. Step S5: After completing the first inoculation, pour the molten iron. During the pouring process, add the second inoculator evenly for a second inoculation and complete the casting. Step S6: Collect several metallographic samples from different locations on the casting and perform metallographic analysis to obtain graphite morphological characteristic values ​​and white iron content. Determine the qualification of inoculation based on the graphite morphological characteristic values. If the condition is unqualified, determine the unqualified stage of inoculation based on the white iron content and determine the adjustment strategy.

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