A multi-stage multi-mode precise temperature control metal solidification process simulation device and method

Abstract

The application discloses a kind of multi-section multi-mode accurate temperature control's metal solidification process simulation device and method, the device includes: crucible, both ends are open, a plurality of thermocouples are equipped on crucible to form a plurality of temperature control points in its inside;Plug, it is slidably arranged in crucible, to seal one end opening;Water cooling mechanism, the other end opening of crucible is connected with water cooling mechanism;Induction heating mechanism, crucible is inserted into induction heating mechanism;Graphite sleeve, it is sleeved on crucible, and insulating layer is sleeved on graphite sleeve;Controller, it is electrically connected with water cooling mechanism, thermocouple and induction heating mechanism respectively.The application provides multi-section multi-mode accurate temperature control's metal solidification process simulation method based on induction heating, realizes the off-line reproduction of the solidification process of target metal in specific area under the process condition of controllable temperature gradient or cooling rate;Meanwhile, liquid metal is indirectly heated by induction heating graphite, shields the factor that electromagnetic stirring liquid metal causes interference simulation solidification.

Description

Technical Field

[0001] This invention relates to the field of metallic materials. More specifically, this invention relates to a method for simulating the metal solidification process with multi-stage, multi-mode, and precise temperature control. Background Technology

[0002] Almost all metals undergo a solidification process during their production. Understanding the metal solidification process, especially the nucleation, crystal growth, microstructure transformation, and defect formation under production conditions, is crucial for the rational development of production processes and new technologies. However, metal solidification is a non-equilibrium dissipative process accompanied by self-organization, making theoretical research on metal solidification exceptionally difficult. This is especially true for steel, with its melting point as high as 1500℃. Due to its high-temperature opacity, the solidification process is invisible and intangible, and it is often produced using continuous large-scale methods such as continuous casting and ingot casting. Therefore, studying the solidification process under production conditions is particularly challenging, severely hindering the optimization of production processes and the development and application of new technologies.

[0003] Extensive research has been conducted by metallurgists and materials scientists on the metal solidification process, resulting in the development of simulation methods such as numerical simulation, material simulation, and geometric simulation. While these methods have their limitations, they have played a crucial role in understanding the metal solidification process. Currently, simulation methods are the primary means of studying the metal solidification process under continuous, large-scale industrial production conditions. Summary of the Invention

[0004] To address the aforementioned problems, this invention provides a device and method for simulating the solidification process of metals using multi-segment, multi-mode, and precise temperature control based on induction heating, enabling offline reproduction of the solidification process of a target metal under specific process conditions.

[0005] To achieve these objectives and other advantages according to the present invention, a multi-stage, multi-mode, precisely temperature-controlled method for simulating metal solidification processes is provided, comprising:

[0006] A crucible with openings at both ends, and multiple thermocouples spaced apart on the crucible to form multiple temperature control points inside it;

[0007] A plug, which is slidably disposed inside the crucible to seal one end opening;

[0008] A water-cooling mechanism, wherein the other end of the crucible is connected to the cooling surface of the water-cooling mechanism;

[0009] An induction heating mechanism, wherein the crucible extends into the induction heating mechanism;

[0010] A graphite sleeve is fitted onto the crucible, and an insulation layer is fitted onto the graphite sleeve.

[0011] The controller is electrically connected to the water cooling mechanism, the thermocouple, the induction heating mechanism, and the drive mechanism, respectively.

[0012] Furthermore, in the aforementioned multi-segment, multi-mode, precise temperature control method for simulating metal solidification processes, the induction heating mechanism is provided with multiple sets of induction coils at intervals, and the number of induction coils is equal to and corresponds one-to-one with the number of temperature control points.

[0013] Furthermore, in the aforementioned multi-segment, multi-mode, precise temperature control method for simulating metal solidification processes, the water-cooling mechanism includes:

[0014] A water-cooled copper head is provided to be connected to the opening at the other end of the crucible;

[0015] A plug is disposed at one end of the crucible opening and connected to a drive unit disposed on the induction heating mechanism. The drive unit drives the plug to abut against the plug and pushes the plug to slide inside the crucible.

[0016] A water circulator is connected to the interior of the water-cooled copper head through a pipe to form a circulating water circuit, and the water circulator is electrically connected to the controller.

[0017] Furthermore, in the aforementioned multi-segment, multi-mode, precise temperature control method for simulating metal solidification processes, the thickness of the graphite sleeve near the water-cooling mechanism is greater than the thickness of its central portion.

[0018] Furthermore, in the aforementioned multi-segment, multi-mode, precise temperature control method for simulating metal solidification processes, the graphite sleeve includes multiple spaced sub-sleeves, and the thickness of the middle sub-sleeve is less than the thickness of the other sub-sleeves.

[0019] This invention also provides a method for simulating metal solidification processes with multi-segment, multi-mode, and precise temperature control. The method includes the following steps:

[0020] S1. Pre-set the metal solidification curve at each temperature control point during the simulation in the controller.

[0021] S2. Place the metal sample in the crucible, then block one end of the crucible opening with the plug, and then insert the crucible into the induction heating mechanism. The induction heating mechanism is tilted so that one end of the crucible tilts downward.

[0022] S3. The induction heating mechanism starts working, and after heating the metal sample to melt, the induction heating mechanism is leveled or the plug is pushed so that the molten metal sample comes into contact with the cooling surface of the water cooling mechanism.

[0023] S4. The controller 12 controls the output power of the induction heating mechanism and the cooling water flow rate of the water cooling mechanism based on the real-time data of each temperature control point measured by the thermocouple, so that the real-time data of each temperature control point matches the metal solidification curve set in S1.

[0024] The method for calculating the metal solidification rate in the metal solidification curve is as follows:

[0025] (1)

[0026] In the above formula, Cooling rate; For heat flux; Surface area; For volume; Specific heat per unit volume; The solid fraction; For time; Latent heat per unit volume;

[0027] The method for calculating the heating amount when the induction heating mechanism is working is as follows:

[0028] (2)

[0029] In the above formula, Q is the Joule heat generated when the induction heating mechanism is working; p is the instantaneous power of induction heating; and t is the heating time. This is the effective value of the voltage; This is the effective value of the current; The inductance of the induction coil; ω is the angular frequency; m is the mass of graphite; c is the specific heat capacity of graphite. This refers to the change in temperature.

[0030] The method for calculating the cooling capacity of the water-cooling mechanism is as follows:

[0031] (3)

[0032] In the above formula, Q1 is the cooling capacity of the water-cooling mechanism; m1 is the mass of the cooling medium; and c1 is the specific heat capacity of the cooling medium. This refers to the change in temperature.

[0033] This method controls the metal solidification rate at each point in Equation (1) above. Equation (2) alone can reduce the sensible heat loss during solidification and decrease the solidification rate, while Equation (3) can increase the heat flux and increase the sensible heat loss. Therefore, the relationship between Equation (3) and Equation (2) above can be used as the interference factor for the sensible heat loss during solidification in Equation 1. Combining Equations (1) and (3) above, the solidification rate controlled by the controller 12 of this invention can be simplified as follows:

[0034] (4)

[0035] In the above formula, This is the interference term for sensible heat loss.

[0036] Furthermore, during the simulation of the target metal solidification process, the controller 12 heats the metal to complete melting through induction heating and then maintains a constant temperature. The molten metal does not release latent heat, so the third term on the right side of the above equation (4) is 0. The metal is in a constant temperature state, so the left side of the above equation (4) is 0. Therefore, the controller can automatically calculate the relationship between the cooling term Q1 and the heating term Q of the target metal, measure the relationship between the cooling water volume of the water-cooled copper head and the induction heating power, and save these variable relationships in the controller.

[0037] Based on the above formula (4), during the metal solidification process, the controller can quickly adjust the temperature curve of each temperature control point to match the metal solidification curve set in S1 by adjusting the power of the induction heating mechanism and the flow rate of cooling water.

[0038] The beneficial effects of this invention are:

[0039] 1. This invention is based on induction heating and uses multi-segment, multi-mode precise temperature control to simulate the metal solidification process. For the actual production processes of metals, especially molten steel, such as continuous casting, ingot casting and casting, a metal solidification process control method is proposed based on the heat transfer consistency of solidification characteristic units.

[0040] 2. The thermal simulation method based on feature units in this invention makes up for the shortcomings of material simulation and numerical simulation in studying solidification structure and predicting defects in actual production solidification process, and realizes offline reproduction of the solidification process of target metal under specific process conditions.

[0041] 3. This invention solves the problems of high cost and long cycle of traditional large castings and forgings, continuous casting billets, etc., which require repeated dissection and analysis, and the problem that simple numerical simulation still has a large gap in predicting the solidification structure and defects of continuous casting billets, ingots and large castings.

[0042] Other advantages, objectives and features of the present invention will become apparent in part from the following description, and in part from those skilled in the art through study and practice of the invention. Attached Figure Description

[0043] Figure 1 This is a schematic diagram of the metal solidification process simulation device described in this invention;

[0044] Figure 2 This is a schematic diagram of a structure of the graphite sleeve described in this invention. Detailed Implementation

[0045] The present invention will now be described in further detail with reference to the accompanying drawings, so that those skilled in the art can implement it based on the description.

[0046] It should be noted that, unless otherwise specified, the experimental methods described in the following embodiments are all conventional methods, and the reagents and materials described are all commercially available unless otherwise specified. In the description of this invention, the terms "lateral", "longitudinal", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0047] like Figure 1 As shown, an embodiment of the present invention provides a multi-segment, multi-mode, precisely temperature-controlled metal solidification process simulation device, comprising:

[0048] The crucible is open at both ends, and multiple thermocouples 3 are spaced apart on the crucible to form multiple temperature control points inside it; the thermocouples 3 are mainly used to monitor the entire heating and cooling process of the metal sample 8 in real time and transmit the data to the controller 12 in a timely manner.

[0049] A plug, which is slidably disposed inside the crucible to seal one end opening; the plug is made of high-temperature resistant, low-thermal-conductivity alumina. The plug not only prevents the molten metal sample 8 from leaking out from the right side, but also keeps the heat loss between the plug and the molten metal sample 8 in contact very low.

[0050] A water-cooling mechanism, wherein the other end of the crucible is connected to the cooling surface of the water-cooling mechanism;

[0051] An induction heating mechanism is provided, in which the crucible extends. Multiple sets of induction coils 4 are spaced apart within the induction heating mechanism, and the number of induction coils 4 is equal to and corresponds one-to-one with the number of temperature control points. The induction heating coils can also be broken into three or more segments (depending on the temperature control point requirements), connected in series to a single induction power supply or connected individually to a single induction power supply. During the solidification process of the metal sample 8, other power supplies (such as pulse power supply, low-frequency power supply, etc.) can be switched as needed.

[0052] A graphite sleeve 6, fitted onto the crucible, serves to convert the magnetic field energy of the induction coil 4 into heat energy to heat the metal sample 8, including the initial melting of the metal sample 8 and the subsequent temperature-controlled solidification. High-quality graphite material possesses properties such as high temperature resistance and high electrical conductivity, allowing nearly 80% of the electromagnetic energy to be converted into heat energy. Simultaneously, the high-frequency magnetic field generated by the induction coil 4 first heats the graphite and then indirectly heats the metal sample 8, exhibiting a certain degree of hysteresis. This effectively prevents the rapid and difficult-to-control temperature rise caused by direct induction heating of the metal sample 8, and avoids the agitation of the molten metal by induction heating, which could disrupt the solidification process. Based on these requirements, the graphite sleeve 6 is made of high-quality graphite material with the following properties: resistivity ≤ 8.5.0 μΩ•m, compressive strength ≥ 24.0 MPa, and density ≥ 1.58 g / cm³. To provide graphite strength and high thermal conductivity, carbon-carbon composite materials can also be used to further reduce the thickness of the graphite sleeve 6.

[0053] To simulate the unidirectional gradient solidification or the gradient solidification from both sides to the middle of the metal sample 8 within the crucible, a controllable temperature gradient is created at different points inside the metal sample 8. With one end of the crucible designated as right and the other as left, the graphite tube can be designed as follows: thicker on the left, thinner in the middle and right; thicker on both sides, thinner in the middle; thickness decreasing linearly from left to right; thickness decreasing linearly from left to middle and then remaining at the right side; thickness decreasing linearly from both sides to the middle. Simultaneously, the graphite sleeve 6 can be divided into: a single continuous sleeve, or as... Figure 2 As shown, multiple sleeves are arranged from left to right, and the thickness of the sleeve in the middle is less than that of the other sleeves; from left to right, pure graphite sleeves and carbon-carbon composite sleeves.

[0054] A thermal insulation layer 5 is fitted onto the graphite sleeve 6; the thermal insulation layer 5 is made of insulating brick or asbestos with good heat insulation performance, which can ensure that the furnace body is a uniform temperature zone in the radial direction (temperature difference ≤1K). The thickness of the thermal insulation layer 5 meets the following requirements: Where d is the thickness of the insulation layer 5, T1 represents the temperature difference between the inside and outside of insulation layer 5, and T1 represents the temperature at the center of the furnace body. The value represents the thermal conductivity of the insulation material. As shown in the formula above, to ensure insulation performance while reducing the thickness of the insulation layer (5%) to increase the furnace cavity space, it is advisable to use insulation bricks or asbestos materials with good insulation properties.

[0055] The controller 12 is electrically connected to the water cooling mechanism, the thermocouple 3, the induction heating mechanism and the drive mechanism respectively.

[0056] In this embodiment, to facilitate the simulation of the solidification requirements of large cast and forged ingots for the metal sample 8, namely, near-adiabatic radial solidification and controllable, orderly gradient solidification axially, an induction coil 4 is installed within the induction heating mechanism. The induction coil 4 is a solenoid coil, which converts electrical energy into magnetic field energy when working, acting on the graphite sleeve 6 to heat the metal sample 8. The output power frequency of the induction coil 4 is high frequency or ultrasonic. The induction coil 4 can be a solenoid with uniform turn spacing; or with a larger turn spacing in the one-third portion near the water-cooling mechanism and a smaller turn spacing in the remaining two-thirds portion; or with a larger turn spacing in the two outer thirds and a smaller turn spacing in the middle third. The controller 12 automatically compares and analyzes the solidification temperature curve and outputs control signals based on the temperature feedback from the thermocouple 3, controlling the cooling medium flow rate of the water-cooling mechanism and the output power of the induction power supply, respectively, to achieve solidification under certain gradient temperature conditions from left to right or from both sides towards the center within the corundum crucible, with a temperature gradient at the leading edge of the liquid-solid transition zone.

[0057] Specifically, the metal solidification process simulation device employing the above-mentioned multi-stage, multi-mode, precise temperature control includes the following steps:

[0058] S1. Pre-set the metal solidification curve at each temperature control point during the simulation in the controller 12;

[0059] S2. Place the metal sample 8 inside the crucible, then block one end of the crucible opening with the plug, and then insert the crucible into the induction heating mechanism. The induction heating mechanism is tilted so that one end of the crucible tilts downward.

[0060] S3. The induction heating mechanism starts working, and after heating the metal sample 8 to melt, the induction heating mechanism is leveled or the plug is pushed so that the molten metal sample 8 comes into contact with the cooling surface of the water cooling mechanism.

[0061] S4. The controller 12 controls the output power of the induction heating mechanism and the circulating water volume of the water cooling mechanism based on the real-time data of each temperature control point measured by the thermocouple 3, so that the real-time data of each temperature control point matches the metal solidification curve set in S1.

[0062] Preferably, in another embodiment of the present invention, the water-cooling mechanism includes:

[0063] A first water-cooled copper head 1 is provided to be connected to the other end opening of the crucible. The first water-cooled copper head 1 is connected to a first driving unit, and the first driving unit drives the first water-cooled copper head 1 to move along the length direction of the crucible.

[0064] The second water-cooled copper head 2 is disposed at one end of the crucible opening and connected to the second drive unit disposed on the induction heating mechanism. The first drive unit drives the second water-cooled copper head 2 to abut against the plug and pushes the plug to slide inside the crucible.

[0065] The water circulator is connected to the first water-cooled copper head 1 and the second water-cooled copper head 2 through pipes to form a circulating water circuit. The water circulator is electrically connected to the controller 12.

[0066] In this embodiment, the first water-cooled copper head 1 is moved along the length of the crucible by the first driving unit, and the position between the crucible and the induction coil 4 is adjusted while the induction heating mechanism is fixed. Figure 1 As shown, the second driving unit drives the second water-cooled copper head 2 to move, and the second water-cooled copper head 2 drives the plug to move inside the crucible, so that the molten metal sample 8 comes into contact with the cooling surface of the water-cooling mechanism. Specifically, the second driving unit can be a sleeve and a round rod coaxially connected. The sleeve is fixed on the induction heating mechanism, and the round rod slides through the sleeve and moves with the second water-cooled copper head 2 to push the plug to move.

[0067] To illustrate the effectiveness of the metal solidification process simulation device with multi-segment, multi-mode, precise temperature control provided by this invention in simulating the metal solidification process, three embodiments are provided:

[0068] Example 1: Optimization of Duplex Stainless Steel Continuous Casting Process

[0069] The cooling process for duplex stainless steel continuous casting was simulated and optimized according to the above-described specific implementation method. Metal sample 8 was a duplex stainless steel bar with a diameter of 20mm and a length of 200mm. Two specifications of graphite sleeves 6 were arranged from left to right in the furnace body: a wall thickness of 3mm and a length of 130mm; and a wall thickness of 1.5mm and a length of 2600mm. A corundum crucible with 95% alumina was selected. The insulation layer 5 consisted of 100mm thick insulating bricks joined together, with the gaps sealed with high-temperature adhesive.

[0070] Step 1: Import the simulation results of solidification temperature at three different points in the first section of the second cooling zone of the duplex stainless steel continuous casting billet into controller 12.

[0071] Step 2: Input the solidification curves at different points into the temperature control program of the controller 12 and the corresponding thermocouple 3 control points. In the initial state, the corundum crucible holding the metal sample 8 is fixed in the induction heating furnace at a certain tilt angle (about 80°), and one end (right end) of the corundum crucible is sealed with a corundum plug (alumina).

[0072] Step 3: Controller 12 sends a signal to control the induction power supply with a frequency of 100kHz to gradually output electrical energy (0~25kW) to the induction coil 4 to heat the graphite sleeve 6 in the furnace.

[0073] Step 4: After the metal sample 8 melts, controller 12 opens the water-cooled copper head valve, controlling the flow rate to 0.5 m³ / s. 3 / h.

[0074] Step 5: Level the furnace body. The molten metal will flow to the left through its own kinetic energy and solidify upon contact with the water-cooled copper head. At the same time, gradually pull the corundum crucible out of the furnace body to the left at a speed of 0.1 m / min.

[0075] Step 6: The controller 12 compares and analyzes the real-time temperature and temperature control curve of each thermocouple 3, and outputs a signal to control the power output of the induction power supply and the cooling water volume of the water-cooled copper head, ensuring that the temperature gradient at the solidification front of the metal test is 30 K / cm and the cooling rate is 20 K / min.

[0076] Dissection and corrosion analysis revealed that, by simulating the solidification conditions of industrial continuous casting for producing duplex stainless steel, almost identical solidification structures and compositional distributions could be obtained. This provides feasibility for subsequent optimization of the continuous casting process for producing duplex stainless steel in the laboratory.

[0077] Example 2: Optimization of continuous casting process for T10A tool steel

[0078] The cooling process for continuous casting of T10A tool steel was simulated and optimized according to the above-described specific implementation method. Metal sample 8 was a duplex stainless steel bar with a diameter of 40mm and a length of 300mm. Two specifications of graphite sleeves 6 were arranged from left to right in the furnace body: the left sleeve had a wall thickness of 5mm (the inner wall thickness gradually decreases to 2.5mm from left to right) and a length of 130mm; the other had a wall thickness of 2mm and a length of 2600mm. A corundum crucible with 95% alumina was selected. The insulation layer 5 consisted of 100mm thick insulating bricks joined together, with the gaps sealed with high-temperature adhesive.

[0079] Step 1: Import the simulation results of solidification temperature at three different points in the second cooling zone of the T10A tool steel continuous casting billet into controller 12.

[0080] Step 2: Input the solidification curves at different points into the temperature control program of the controller 12 and the corresponding thermocouple 3 control points. In the initial state, the corundum crucible holding the metal sample 8 is fixed in the induction heating furnace at a certain tilt angle (about 80°), and one end (right end) of the corundum crucible is sealed with a corundum plug (alumina).

[0081] Step 3: Controller 12 sends a signal to control the induction power supply with a frequency of 100kHz to gradually output electrical energy (0~25kW) to the induction coil 4 to heat the graphite sleeve 6 in the furnace.

[0082] Step 4: After the metal sample 8 melts, controller 12 opens the water-cooled copper head valve, controlling the flow rate to 0.9 m³ / s. 3 / h.

[0083] Step 5: Level the furnace body, and the molten metal will flow to the left through its own kinetic energy and come into contact with the water-cooled copper head to solidify.

[0084] Step 6: The controller 12 compares and analyzes the real-time temperature and temperature control curve of each thermocouple 3, and outputs a signal to control the power output of the induction power supply and the cooling water volume of the water-cooled copper head, ensuring that the temperature gradient at the solidification front of the metal test is 80 K / cm and the cooling rate is 30 K / min.

[0085] Dissection and corrosion analysis revealed that, by simulating the solidification conditions of industrial continuous casting for producing T10A tool steel, almost identical solidification microstructure and compositional distribution could be obtained. This provides feasibility for subsequent optimization of the continuous casting process for producing T10A tool steel in the laboratory.

[0086] Example 3: Automatic Control Mode and Process of Controller 12

[0087] The continuous casting cooling process for T10A tool steel was simulated and optimized according to the above-described specific implementation procedure. Metal sample 8 was a duplex stainless steel bar with a diameter of 40mm and a length of 300mm. Two specifications of graphite sleeves 6 were arranged from left to right in the furnace body, with the following specifications: the first section on the left had a wall thickness of 8mm, the second section 5mm, the third section 2mm, the fourth section 5mm, and the fifth section 2mm, all with a length of 75mm. A corundum crucible with 95% alumina was used. The insulation layer 5 consisted of 100mm thick insulating bricks joined together, with the gaps sealed with high-temperature adhesive. After the T10A tool steel melted, controlled solidification was performed.

[0088] Step 1: Import the simulation results of solidification temperature at three different points in the second cooling zone of the T10A tool steel continuous casting billet into controller 12.

[0089] Step 2: The controller 12 heats the T10A tool steel to complete melting through induction heating and then maintains a constant temperature. The molten metal does not release latent heat. Based on the above formula (4), the controller 12 can automatically calculate the relationship between the cooling water volume of the water-cooled copper head and the induction heating power during the solidification process of T10A tool steel (balance point: water-cooled copper head flow rate 0 m3 / h, that is, the copper head does not contact the sample; induction heating power 23.5kW), and save these variable relationships in the controller 12.

[0090] Controller 12 executes PID control based on the temperature feedback from thermocouples 3 at different locations. For the water-cooled copper head near the left end, when the difference between the thermocouple 3 feedback temperature and the set temperature is greater than 10K, controller 12 outputs a 4~20mA signal to adjust the flow control valve of the water-cooled copper head. When the difference between the thermocouple 3 feedback temperature and the set temperature is less than 10K, controller 12 maintains the flow rate and quickly switches to outputting a 0~20mA signal to control the power output of the inductive power supply, keeping the difference between the thermocouple 3 feedback temperature and the set temperature less than ±1K.

[0091] Step 3: At the indirect contact point far from the left end of the water-cooled copper head, the controller 12 automatically adjusts the output of a 0~20mA signal to control the power output of the induction power supply by preset the thickness of the graphite sheet at this position and the number of turns per unit distance of the induction coil 4, so as to keep the difference between the feedback temperature of the thermocouple 3 and the set temperature less than ±1K.

[0092] Step 4: Controller 12, in conjunction with the power output of the inductive power supply and the cooling water volume of the water-cooled copper head, ensures that the temperature gradient at the solidification front of the metal test is 80 K / cm and the cooling rate is 30 K / min. The solidification curve of T10A tool steel is almost identical to the curve set in S1.

[0093] Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and embodiments shown and described herein.

Claims

1. A method for simulating the metal solidification process with multi-segment, multi-mode, and precise temperature control, characterized in that, A metal solidification process simulation device employing multi-segment, multi-mode, and precise temperature control, the simulation device comprising: A crucible with openings at both ends, and multiple thermocouples spaced apart on the crucible to form multiple temperature control points inside it; A plug, which is slidably disposed inside the crucible to seal one end opening; A water-cooling mechanism, wherein the other end of the crucible is connected to the cooling surface of the water-cooling mechanism; An induction heating mechanism, wherein the crucible extends into the induction heating mechanism; A graphite sleeve is fitted onto the crucible, and an insulation layer is fitted onto the graphite sleeve. The controller is electrically connected to the water-cooling mechanism, the thermocouple, and the induction heating mechanism, respectively. The induction heating mechanism is provided with multiple sets of induction coils and multiple sections of graphite sleeves at intervals. The number of induction coils and graphite sleeves is equal to the number of temperature control points and corresponds one-to-one. The graphite tube is designed to be thicker on the left and thinner in the middle and right, thicker on both sides and thinner in the middle, with the thickness decreasing linearly from left to right, with the thickness decreasing linearly from left to middle and then maintaining the thickness to the right, or with the thickness decreasing linearly from both sides to the middle. The simulation method includes the following steps: S1. Pre-set the metal solidification curve at each temperature control point during the simulation in the controller. S2. Place the metal sample in the crucible, then block one end of the crucible opening with the plug, and then insert the crucible into the induction heating mechanism. The induction heating mechanism is tilted so that one end of the crucible tilts downward. S3. The induction heating mechanism starts working, and after heating the metal sample to melt, the induction heating mechanism is leveled or the plug is pushed so that the molten metal sample comes into contact with the cooling surface of the water cooling mechanism. S4. The controller controls the output power of the induction heating mechanism and the cooling water flow rate of the water cooling mechanism based on the real-time data of each temperature control point measured by the thermocouple, so that the real-time data of each temperature control point matches the metal solidification curve set in S1. The method for calculating the metal solidification rate in the metal solidification curve is as follows: （1）； In the above formula, Cooling rate; For heat flux; Surface area; For volume; Specific heat per unit volume; The solid fraction; For time; Latent heat per unit volume; The method for calculating the heating amount when the induction heating mechanism is working is as follows: （2）； In the above formula, Q is the Joule heat generated when the induction heating mechanism is working; p is the instantaneous power of induction heating; and t is the heating time. This is the effective value of the voltage; This is the effective value of the current; The inductance of the induction coil; ω is the angular frequency; m is the mass of graphite; c is the specific heat capacity of graphite. This refers to the change in temperature. The method for calculating the cooling capacity of the water-cooling mechanism is as follows: （3）； In the above formula, Q1 is the cooling capacity of the water-cooling mechanism; m1 is the mass of the cooling medium; and c1 is the specific heat capacity of the cooling medium. This refers to the change in temperature. Combining equations (1)-(3) above, the calculation method for the solidification rate controlled by the controller is as follows: （4）； In the above formula, The controller controls the solidification rate; This is the interference term for sensible heat loss; When simulating the solidification process of the target metal, the controller heats it to complete melting through induction heating and then maintains a constant temperature. The molten metal does not release latent heat, so the third term on the right side of the above formula (4) is 0. When the metal is in a constant temperature state, the left side of the above formula (4) is 0. The controller automatically calculates the relationship between the target metal cooling term Q1 and the heating term Q, measures the relationship between the cooling water volume of the water-cooled copper head and the induction heating power, and saves the variable relationship to the controller. Based on the above formula (4), during the metal solidification process, the controller adjusts the power of the induction heating mechanism and the flow rate of the cooling water to quickly adjust the temperature curve of each temperature control point to match the metal solidification curve set in S1.

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