Casting and heat treatment temperature control device based on gas-solid dynamic suspension and control method thereof

Abstract

The application discloses a casting and heat treatment temperature control device based on gas-solid dynamic suspension and a control method thereof. The device can realize high-performance consistent casting and component consistent heat treatment. By lifting the height of the dynamic suspension mixture of the heat-conducting solid particles and the gas from bottom to top in the heating cavity, the casting can be solidified layer by layer, the cold speed during the solidification of the casting can be significantly enhanced, the uniformity and consistency of the temperature of each region during the solidification of the casting can be improved, the grain is refined, the secondary dendrite arm spacing is shortened, the defects are reduced, the residual stress of the casting after solidification is reduced, the uniform solidification structure is obtained, and finally the casting with high performance and consistent mechanical properties of each region is obtained. Meanwhile, the dynamic suspension of the mixture can also realize rapid heating of the heat treatment component, shorten the heat treatment time, overcome the problem of uneven temperature in the traditional heat treatment, realize the temperature consistency and uniform distribution, and thus obtain the uniform heat treatment structure and the heat treatment component with consistent mechanical properties of each region.

Description

Technical Field

[0001] This invention belongs to the technical field of digital intelligent casting, specifically relating to a casting and heat treatment temperature control device and its control method based on gas-solid dynamic suspension. Background Technology

[0002] The performance and quality of castings or components largely depend on the formation of their microstructure during cooling, solidification, and heat treatment. The cooling rate and temperature distribution during solidification have a direct and profound impact on the grain structure, mechanical properties, and residual stress of castings. However, traditional casting solidification processes mostly use air as the heat transfer medium. Due to air's weak thermal conductivity and low heat transfer efficiency, the cooling rate of the casting is low, leading to coarse grains, increased secondary dendrite arm spacing, and defects such as porosity and cracks, severely affecting the mechanical properties of the casting. Simultaneously, the non-uniform temperature distribution in air results in uneven temperature distribution during solidification, leading to inconsistent cooling rates in different regions of the casting, resulting in inconsistent microstructure, significant differences in mechanical properties, and high residual stress. Similarly, the uniformity of temperature distribution is crucial during the heat treatment of components. However, traditional heat treatment processes mainly rely on air as the heat transfer medium, which has insufficient thermal conductivity, resulting in slow temperature rise of components during heat treatment. Furthermore, air heat transfer is easily affected by environmental factors, leading to significant temperature fluctuations. Especially when treating complex-shaped components with overall heating or heat preservation, significant temperature differences may occur in different areas due to uneven heating, making it impossible to achieve uniform temperature distribution. This results in inconsistent local evolution of the microstructure and inconsistent mechanical properties across different regions. Therefore, traditional casting cooling and solidification processes and component heat treatment processes have significant limitations in terms of temperature uniformity and high-precision temperature control, making it difficult to meet the high requirements for high-performance consistent casting and consistent heat treatment of components. This deficiency not only limits the improvement of casting and component performance but also significantly affects their reliability in high-performance applications.

[0003] Therefore, there is an urgent need to provide a new solution to address the defects and shortcomings of the existing technologies. Summary of the Invention

[0004] To address the deficiencies and shortcomings of the existing technologies, this invention provides a casting and heat treatment temperature control device and its control method based on gas-solid dynamic suspension.

[0005] The technical effects of this invention are achieved by adopting the following technical solution:

[0006] The casting and heat treatment temperature control device based on gas-solid dynamic suspension is characterized by: including a gas-solid suspension cavity, the top of which is provided with a sealing cover plate; a controllable heating device is provided outside the gas-solid suspension cavity; and the interior of the gas-solid suspension cavity is uniformly filled with a mixture of thermally conductive solid particles and gas.

[0007] The inner wall of the gas-solid suspension cavity is equipped with an infrared temperature sensor and a thermocouple. A thermally conductive solid particle channel is connected between the bottom of the gas-solid suspension cavity and the thermally conductive particle storage device. A particle control valve and a particle flow controller are installed on the thermally conductive solid particle channel.

[0008] The bottom of the gas-solid suspension cavity is provided with a gas diversion device and an air inlet channel. The gas diversion device is provided with a buffer chamber inside, and the buffer chamber is connected to the inside of the gas-solid suspension cavity through multiple diversion channels. The gas diversion device is connected to a gas storage device through the air inlet channel, and a gas control valve and a gas flow controller are installed on the air inlet channel.

[0009] The temperature control device is located on the top of the base. A lifting column and a lifting device are installed on one side of the base. The lifting device can move up and down along the lifting column and rotate around the lifting column.

[0010] A first crossbeam is connected to one side of the lifting device. A cooling and solidification treatment fixing device is connected to the bottom of the first crossbeam through a fitting device. The bottom of the cooling and solidification treatment fixing device is provided with a multi-hole channel. A mold is fixed inside the cooling and solidification treatment fixing device. Molten metal to be cooled and solidified is poured into the cavity of the mold.

[0011] A second crossbeam is connected to the other side of the lifting device; a heat treatment fixing device is connected to the lower part of the second crossbeam by a rope, and the heat treatment fixing device is provided with multiple perforated channels around its perimeter, and the component to be heat treated is fixed in the heat treatment fixing device.

[0012] As a further preferred embodiment of the present invention, the heating element of the controllable heating device is selected from at least one or more combinations of iron-chromium-aluminum wire, molybdenum wire and tungsten wire.

[0013] As a further preferred embodiment of the present invention, the thermally conductive solid particles are selected from at least one or more combinations of carbon, graphite, diamond, aluminum nitride, silicon nitride, boron nitride, silicon carbide, carbon nanotubes, graphene, magnesium oxide, aluminum oxide, zinc oxide, silicon dioxide, gold, silver, copper, aluminum, magnesium, iron, and stainless steel.

[0014] As a further preferred embodiment of the present invention, the gas medium in the gas storage device is selected from at least one or more of water vapor, compressed air, nitrogen, hydrogen, oxygen, carbon dioxide, argon, neon, helium, krypton and xenon, and the gas medium is selected from cooled or heated gas.

[0015] As a further preferred embodiment of the present invention, the cooling and solidification treatment fixing device is fixed to the mold by a wedge fit; the bottom of the heat treatment fixing device is provided with an elastic clamping structure for fixing the component to be heat treated.

[0016] As a further preferred embodiment of the present invention, the infrared temperature sensor is uniformly distributed layer by layer in the gas-solid suspension cavity to monitor and provide feedback on the temperature of each layer of the heat treatment component and the molten metal to be cooled and solidified in the mold in real time; the thermocouple is set at the bottom of the infrared temperature sensor in the gas-solid suspension cavity to monitor the temperature of the mixture of heat-conducting solid particles and gas in real time to determine whether the preset temperature has been reached.

[0017] As a further preferred embodiment of the present invention, the flow of thermally conductive solid particles from the thermally conductive particle storage device is controlled by a particle control valve, and the flow of thermally conductive solid particles into the thermally conductive particle storage device is controlled by a particle flow controller; the flow rate and pressure of the thermally conductive solid particles in the thermally conductive solid particle channel are regulated by a particle flow controller.

[0018] The flow of gas from the gas storage device is controlled by a gas control valve; the flow rate and pressure of the gas in the inlet channel are regulated by a gas flow controller.

[0019] As a further preferred embodiment of the present invention, the control priority of the gas control valve is higher than that of the particle control valve; the control priority of the gas flow controller is higher than that of the particle flow controller.

[0020] Furthermore, when controlling the input gas through gas control valves and gas flow controllers, the control priority of gas pressure is higher than that of gas flow, and the control priority of gas flow is higher than that of the control priority of the input gas time.

[0021] As a further preferred embodiment of the present invention, the mass of particles to be added inside the gas-solid suspension cavity satisfies the following formula:

[0022] M 补 =K1×Q 气 ×ρ 固 ×t

[0023] in,

[0024] M 补 The mass of particles to be replenished, in kg;

[0025] K1 is a coefficient that is related to the density characteristics of the thermally conductive solid particles, and its value is determined based on the density of the thermally conductive solid particles.

[0026] Q 气 The flow rate of the gas is m³ / s;

[0027] ρ 固 ρ is the density of the thermally conductive solid particles in the gas-solid suspension cavity, in kg / m³;

[0028] t is the time for gas input, in seconds;

[0029] The height of the heat-conducting solid particles and gas mixture inside the gas-solid suspension cavity satisfies the following formula:

[0030] H = K2 × P / P0 × h + H0

[0031] in,

[0032] H is the height of the thermally conductive solid particle and gas mixture, in mm;

[0033] K2 is a coefficient that is related to the density characteristics of the thermally conductive solid particles, and its value is determined based on the density of the thermally conductive solid particles.

[0034] P is the pressure of the input gas, in bars;

[0035] P0 is the reference value selected to achieve dimensionlessness, P0 = 1 bar;

[0036] h is the reference value selected for converting air pressure into altitude, h=1mm;

[0037] H0 is the initial height of the mixture of thermally conductive solid particles and gas, in mm.

[0038] Furthermore, the present invention also provides a control method for a casting and heat treatment temperature control device based on gas-solid dynamic suspension, characterized by comprising the following steps:

[0039] Step S1: Rotate the lifting device so that the mold containing the molten metal to be cooled and solidified in the cavity is above the gas-solid suspension cavity; open the sealing cover plate, and then control the lifting device to descend, so that the mold containing the molten metal to be cooled and solidified in the cavity, which is fixed in the cooling and solidification treatment fixing device, is slowly lowered to the preset height in the gas-solid suspension cavity, so that the mold containing the molten metal to be cooled and solidified in the cavity is completely inserted into the gas-solid suspension cavity;

[0040] Step S2: Based on the structural characteristics of the mold in which the molten metal to be cooled and solidified is poured, open the particle control valve to control the heat-conducting solid particles to enter the gas-solid suspension cavity from the heat-conducting particle storage device through the heat-conducting solid particle channel. At the same time, open the gas control valve to control the gas to enter the gas-solid suspension cavity from the gas storage device through the gas inlet channel.

[0041] Step S3: Adjust the particle supply and gas flow rate respectively through the particle flow controller and gas flow controller to make the heat-conducting solid particles and gas mixture inside the gas-solid suspension cavity form a uniform gas-solid dynamic suspension state and reach the preset height, so that the heat-conducting solid particles and gas mixture can completely cover the mold in the cavity into which the molten metal to be cooled and solidified is poured.

[0042] Step S4: After the molten metal to be cooled and solidified is completed, stop the gas input and open the particle control valve to allow the heat-conducting solid particles to flow back, so that the height of the heat-conducting solid particles gradually decreases until they are separated from the cooling and solidification treatment fixing device. Then, slowly lift the cooling and solidification treatment fixing device from the gas-solid suspension chamber using the lifting device until the cooling and solidification treatment fixing device is separated from the gas-solid suspension chamber. Then, remove the mold from the cooling and solidification treatment fixing device, and finally remove the cooled and solidified casting from the mold.

[0043] Step S5: Rotate the lifting device to position the component to be heat-treated above the gas-solid suspension chamber; open the particle control valve to control the heat-conducting solid particles to enter the gas-solid suspension chamber from the heat-conducting particle storage device through the heat-conducting solid particle channel, and at the same time open the gas control valve to control the gas to enter the gas-solid suspension chamber from the gas storage device through the gas inlet channel. The particle supply and gas flow are adjusted by the particle flow controller and the gas flow controller respectively, so that the heat-conducting solid particles and gas mixture inside the gas-solid suspension chamber form a uniform gas-solid dynamic suspension state and reach the preset height, so that the heat-conducting solid particles and gas mixture can completely cover the component to be heat-treated.

[0044] Step S6: According to the required heat treatment process of the component to be heat-treated, the target temperature in the gas-solid suspension cavity is preset. The mixture of heat-conducting solid particles and gas is precisely heated by an external controllable heating device. The temperature of the mixture of heat-conducting solid particles and gas is monitored in real time by a thermocouple until the temperature of the mixture of heat-conducting solid particles and gas reaches the preset target temperature.

[0045] Step S7: Open the sealing cover, and then control the lifting device to descend, slowly lowering the component to be heat-treated, which is fixed in the heat treatment fixing device, to the preset height in the gas-solid suspension cavity, so that the component to be heat-treated is completely inserted into the gas-solid suspension cavity and immersed in the mixture of dynamically suspended heat-conducting solid particles and gas, and then heat-treated.

[0046] Step S8: After the heat treatment reaches the preset time, gradually reduce the heating power of the controllable heating device and simultaneously control the reduction of the gas flow rate, so that the component to be heat-treated gradually cools to a safe temperature range under controlled conditions; then, stop the gas input, and after the particles in the gas-solid suspension chamber are reduced to the point of separation from the heat treatment fixing device, slowly lift the heat treatment fixing device from the gas-solid suspension chamber using the lifting device until the heat treatment fixing device is separated from the gas-solid suspension chamber; then remove the heat-treated component from the heat treatment fixing device.

[0047] Compared with the prior art, the beneficial technical effects achieved by the present invention include:

[0048] 1) This invention provides a casting and heat treatment temperature control device and its control method based on gas-solid dynamic suspension. By utilizing the dynamic synergistic effect of thermally conductive solid particles and gas, a stable gas-solid dynamic suspension state is formed, thereby achieving high-performance and consistent casting of the molten metal to be cooled and solidified in the mold and consistent heat treatment of the components to be heat treated.

[0049] 2) This invention provides a casting and heat treatment temperature control device and its control method based on gas-solid dynamic suspension. By dynamically suspending the mixture of heat-conducting solid particles and gas, and utilizing the rapid synergistic heat exchange and dynamic flow mechanism between the heat-conducting particles and gas, the cooling rate during the cooling and solidification process of the molten metal in the mold is significantly enhanced. This not only improves the cooling efficiency, but also effectively promotes grain refinement, shortens the secondary dendrite arm spacing, and thus improves the mechanical properties of the casting.

[0050] 3) This invention provides a casting and heat treatment temperature control device and its control method based on gas-solid dynamic suspension. By increasing the dynamic suspension height of the heat-conducting solid particles and gas mixture from bottom to top, the molten metal to be cooled and solidified in the mold is cooled and solidified layer by layer. This method can replenish the molten metal in time to compensate for shrinkage and ensure effective compensation for the volume shrinkage of the casting during the cooling and solidification process. This effectively reduces the generation of defects in the casting, such as porosity, shrinkage cavities, and cracks, and significantly improves the mechanical properties and reliability of the casting after cooling and solidification.

[0051] 4) This invention provides a casting and heat treatment temperature control device and its control method based on gas-solid dynamic suspension. By adopting dynamic suspension technology of thermally conductive solid particles and gas mixture, the temperature uniformity and cooling rate consistency of the entire casting during the cooling and solidification process are ensured, thereby effectively guaranteeing the consistency of the microstructure of each region of the casting during the cooling and solidification process, and further realizing the consistency of the mechanical properties of each region of the casting after cooling and solidification.

[0052] 5) This invention provides a casting and heat treatment temperature control device and method based on gas-solid dynamic suspension. By employing dynamic suspension technology of thermally conductive solid particles and gas mixture, it not only significantly improves the temperature uniformity of the molten metal poured into the mold cavity during the cooling and solidification process, but also effectively overcomes the problem of inconsistent shrinkage caused by local temperature unevenness in traditional casting processes, thereby significantly reducing the residual stress of the casting. In this way, the temperature of each area of ​​the mold remains consistent during the cooling and solidification process, thus obtaining high-performance castings with low residual stress.

[0053] 6) This invention provides a casting and heat treatment temperature control device and method based on gas-solid dynamic suspension. By dynamically suspending a mixture of heat-conducting solid particles and gas within the heating chamber, and utilizing the rapid convective heat transfer characteristics of the heat-conducting particles and gas, as well as the dynamic flow process of the particles, a stable and efficient gas-solid dynamic suspension state is formed, thereby significantly improving temperature uniformity. This method not only enables rapid heating of the components to be heat-treated and shortens the heat treatment time, but also effectively overcomes the problem of temperature non-uniformity in traditional heat treatment processes and the inconsistent local evolution of microstructure caused by temperature non-uniformity. It achieves uniform temperature and high consistency of microstructure evolution in all regions of the component during heat treatment, thereby ensuring consistent mechanical properties and high reliability in all regions of the component.

[0054] 7) This invention provides a casting and heat treatment temperature control device and its control method based on gas-solid dynamic suspension. The same device can realize the cooling and solidification process of the molten metal to be cooled and solidified in the mold and the heat treatment process of the component to be heat treated. On the one hand, it can realize the timely subsequent heat treatment of the casting obtained by cooling and solidification. At the same time, the subsequent heat treatment of the casting with residual heat can reduce the heat treatment energy consumption. On the other hand, it can significantly save resources and space and increase the scope of application. Attached Figure Description

[0055] Figure 1 This is a schematic diagram of the temperature control processing device provided by the present invention;

[0056] Figure 2 The diagram shows the structure of the mold provided by the present invention. The mold contains molten metal that needs to be cooled and solidified. After the molten metal cools and solidifies, a casting is formed.

[0057] Figure 3 This is a schematic diagram of the structure of the component to be heat-treated provided by the present invention;

[0058] Figure 4 The flowchart of steps S1 to S4 in the control method provided by the present invention;

[0059] Figure 5 The flowchart of steps S6 to S8 in the control method provided by the present invention;

[0060] In the picture:

[0061] 1-Controllable heating device; 2-Gas-solid suspension chamber; 3-Infrared temperature sensor; 4-Thermocouple; 5-Heat-conducting solid particles; 6-Lifting column; 7-Base; 8-Gas diversion device; 9-Inlet channel; 10-1-Particle control valve; 10-2-Gas control valve; 11-Heat-conducting solid particle channel; 12-Sealing cover plate; 13-Cooling and solidification treatment fixing device; 14-Melt metal to be cooled and solidified; 15-Casting mold; 16-Matching device; 17-Crossbeam; 18-Lifting device; 19-Crossbeam; 20-Rope; 21-Heat treatment fixing device; 22-Component; 23-Elastic holding structure; 24-Heat-conducting particle storage device; 25-Gas storage device; 26-1-Particle flow controller; 26-2-Gas flow controller. Detailed Implementation

[0062] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0063] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," "outer," "front end," "rear end," "both ends," "one end," and "the other end," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and for 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. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0064] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," "connected," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0065] like Figure 1 The figure shows the casting and heat treatment temperature control device based on gas-solid dynamic suspension provided by the present invention, including a gas-solid suspension cavity 2, the top of which is provided with a sealing cover plate 12; a controllable heating device 1 is provided outside the gas-solid suspension cavity 2; the interior of the gas-solid suspension cavity 2 is uniformly filled with a mixture of thermally conductive solid particles 5 and gas. Through the synergistic effect of the thermally conductive solid particles 5 and gas, the uniform cooling of the casting to be cooled and solidified during the cooling and solidification process and the high-temperature uniformity heat treatment process of the component to be heat treated are achieved; in this embodiment, the heating element of the controllable heating device 1 is selected from at least one or more combinations of iron-chromium-aluminum wire, molybdenum wire and tungsten wire.

[0066] The inner wall of the gas-solid suspension cavity 2 is equipped with an infrared temperature sensor 3 and a thermocouple 4. The infrared temperature sensor 3 is used to monitor the real-time temperature distribution of the casting to be cooled and solidified and the component to be heat-treated, so as to ensure the uniformity and accuracy of the temperature of the casting to be cooled and solidified and the component to be heat-treated during the heat treatment process. The thermocouple 4 is used to monitor the temperature of the heat-conducting solid particles 5 and the gas mixture in real time to determine whether the temperature of the mixture has reached the preset temperature.

[0067] A thermally conductive solid particle channel 11 is connected between the bottom of the gas-solid suspension chamber 2 and the thermally conductive particle storage device 24 to replenish or recover thermally conductive solid particles 5 from the gas-solid suspension chamber 2. A particle control valve 10-1 and a particle flow controller 26-1 are installed on the thermally conductive solid particle channel 11. The particle control valve 10-1 controls the flow of thermally conductive solid particles 5 from the thermally conductive particle storage device 24 and controls the flow of thermally conductive solid particles 5 into the thermally conductive particle storage device 24. The particle flow controller 26-1 controls the flow rate and pressure regulation of thermally conductive solid particles 5 in the thermally conductive solid particle channel 11. In this embodiment, the thermally conductive solid particles 5 are selected from at least one or more combinations of carbon, graphite, diamond, aluminum nitride, silicon nitride, boron nitride, silicon carbide, carbon nanotubes, graphene, magnesium oxide, aluminum oxide, zinc oxide, silicon dioxide, gold, silver, copper, aluminum, magnesium, iron, and stainless steel.

[0068] The bottom of the gas-solid suspension chamber 2 is equipped with a gas diversion device 8 and an air inlet channel 9. The gas diversion device 8 contains a buffer chamber, which is connected to the interior of the gas-solid suspension chamber 2 via multiple diversion channels. The buffer chamber provides temporary gas storage, while the diversion channels ensure uniform gas distribution during release, thus forming a stable gas-solid suspension state. The gas diversion device 8 is connected to the gas storage device 25 via the air inlet channel 9. The air inlet channel 9 is equipped with a gas control valve 10-2 and a gas flow controller 26-2. The gas control valve 10-2 controls the flow of gas from the gas storage device 25. It is worth noting that the gas is not recovered because both the cooling and solidification treatment fixture 13 and the heat treatment fixture 21 are set as open environments during the heat treatment or cooling process, and the gas can directly overflow into the air; the gas flow rate and pressure in the air intake channel 9 are controlled by the gas flow controller 26-2; in this embodiment, the gas medium in the gas storage device 25 is selected from at least one or more of water vapor, compressed air, nitrogen, hydrogen, oxygen, carbon dioxide, argon, neon, helium, krypton and xenon, and the gas medium is selected as a cooled or heated gas.

[0069] The casting and heat treatment temperature control device based on gas-solid dynamic suspension provided in this embodiment is set on the top of the base 7. A lifting column 6 and a lifting device 18 are installed on one side of the base 7. The lifting device 18 can move up and down along the lifting column 6 and rotate around the lifting column 6. The lifting action of the lifting device 18 realizes the placement of the casting to be cooled and solidified and the component to be heat treated into the gas-solid suspension cavity 2 or removes them from the gas-solid suspension cavity 2. The rotation of the lifting device 18 around the lifting column 6 realizes the switching of the position of the casting to be cooled and solidified and the component to be heat treated above the gas-solid suspension cavity 2.

[0070] A first crossbeam 17 is connected to one side of the lifting device 18, and a cooling and solidification treatment fixing device 13 is connected to the bottom of the first crossbeam 17. The bottom of the cooling and solidification treatment fixing device 13 is provided with a porous channel for the inflow of a mixture of heat-conducting solid particles and gas. A mold 15 containing molten metal 14 to be cooled and solidified is fixed inside the cooling and solidification treatment fixing device 13. In this embodiment, the cooling and solidification treatment fixing device 13 and the mold 15 are fixed by a wedge fit, thereby further improving the positioning stability of the mold 15 inside the cooling and solidification treatment fixing device 13, and thus ensuring that the cooling process is uniform, sufficient and stable.

[0071] A second crossbeam 19 is connected to the other side of the lifting device 18; a heat treatment fixing device 21 is connected to the lower part of the second crossbeam 19 by a rope 20. The heat treatment fixing device 21 is provided with a porous channel around its perimeter for conducting the inflow of a mixture of heat-conducting solid particles and gas. The heat treatment fixing device 21 is fixed with a component 22 to be heat-treated. In this embodiment, an elastic clamping structure 23 is provided at the bottom of the heat treatment fixing device 21 to fix the component 22 to be heat-treated, thereby further improving the positioning stability of the component 22 to be heat-treated inside the heat treatment fixing device 21, and thus ensuring that the heat treatment process is uniform, sufficient and stable.

[0072] like Figure 1 As shown, in this embodiment, the infrared temperature sensor 3 is uniformly distributed layer by layer in the gas-solid suspension cavity 2 to monitor and provide feedback on the temperature of each layer of the casting to be cooled and solidified during the cooling and solidification process, so as to achieve a uniform cooling and solidification effect for each layer of the casting to be cooled and solidified during the cooling and solidification process; the thermocouple 4 is set at the bottom of the infrared temperature sensor 3 in the gas-solid suspension cavity 2 to monitor the temperature of the mixture of heat-conducting solid particles 5 and gas in real time, so as to determine whether the temperature required for heat treatment of the component 22 has been reached.

[0073] In this embodiment, the mass of thermally conductive solid particles that need to be added inside the gas-solid suspension cavity 2 satisfies the following formula:

[0074] M 补 =K1×Q 气 ×ρ 固 ×t

[0075] in,

[0076] M 补 The mass of particles to be replenished, in kg;

[0077] K1 is a coefficient that is related to the density characteristics of the thermally conductive solid particles, and its value is determined based on the density of the thermally conductive solid particles.

[0078] Q 气 The flow rate of the gas is m³ / s;

[0079] ρ 固 ρ is the density of the thermally conductive solid particles in the gas-solid suspension cavity, in kg / m³;

[0080] t is the time for gas input, in seconds;

[0081] The height of the thermally conductive solid particles 5 and the gas mixture inside the gas-solid suspension cavity 2 satisfies the following formula:

[0082] H = K2 × P / P0 × h + H0

[0083] in,

[0084] H is the height of the thermally conductive solid particle 5 and the gas mixture, in mm;

[0085] K2 is a coefficient that is related to the density characteristics of the thermally conductive solid particles, and its value is determined based on the density of the thermally conductive solid particles.

[0086] P is the pressure of the input gas, in bars;

[0087] P0 is the reference value selected to achieve dimensionlessness, P0 = 1 bar;

[0088] h is the reference value selected for converting air pressure into altitude, h=1mm;

[0089] H0 is the initial height of the thermally conductive solid particle 5 and the gas mixture, in mm.

[0090] As can be seen, once the type of thermally conductive solid particles 5 is selected, the mass of particles to be replenished and the height of the mixture of thermally conductive solid particles 5 and gas are both related to the gas parameters. Therefore, it is possible to set the gas control valve 10-2 to open first, followed by the particle control valve 10-1, to determine the mass of particles to be replenished and the current height of the mixture of thermally conductive solid particles 5 and gas inside the gas-solid suspension chamber 2 based on parameters such as the pressure, flow rate, and time of the input gas. This further confirms the required replenishment amount and height of particles entering the gas-solid suspension chamber 2. Simultaneously, it can also pre-expel other mixed gases from the thermally conductive solid particles 5 entering the gas-solid suspension chamber 2, providing a stable dynamic suspension environment.

[0091] During cooling solidification and heat treatment, the gas flow controller needs to be adjusted first, and the flow rate of the heat-conducting solid particles 5 is adjusted accordingly based on the adjustment result of the gas flow controller. Furthermore, when controlling the input gas through the gas control valve 10-2 and the gas flow controller 26-2, the control priority of gas pressure is higher than that of gas flow rate, and the control priority of gas flow rate is higher than that of the input gas time. The purpose of this setting is that gas pressure directly affects the dynamic suspension state and high stability of the gas-solid mixture. Appropriate gas pressure can ensure uniform dynamic suspension of the gas-solid mixture and uniform coverage of the casting or component, thereby ensuring a uniform temperature field distribution during cooling solidification or heat treatment, and ensuring the realization of the beneficial effects of the cooling solidification or heat treatment process. Gas flow rate affects the flow rate of the gas-solid mixture and the dynamic stability of particle suspension, thus indirectly affecting the efficiency and uniformity of heat transfer during cooling solidification or heat treatment. Gas input time mainly affects the continuity and stages of the process, with a relatively small direct impact on the real-time process.

[0092] This invention also provides a control method for a casting and heat treatment temperature control device based on gas-solid dynamic suspension, comprising the following steps:

[0093] Step S1: Rotate the lifting device 18 so that the mold 15, in which the molten metal 14 to be cooled and solidified is poured, is located above the gas-solid suspension cavity 2; open the sealing cover plate 12, and then control the lifting device 18 to descend, so that the mold 15, in which the molten metal 14 to be cooled and solidified is poured, fixed in the cooling and solidification treatment fixing device 13, is slowly lowered to the preset height in the gas-solid suspension cavity 2, so that the mold 15, in which the molten metal 14 to be cooled and solidified is poured, is completely inserted into the gas-solid suspension cavity 2;

[0094] Step S2: Based on the structural characteristics of the mold 15 in which the molten metal 14 to be cooled and solidified is poured into the cavity, open the particle control valve 10-1 to control the heat-conducting solid particles 5 to enter the gas-solid suspension cavity 2 from the heat-conducting particle storage device 24 through the heat-conducting solid particle channel 11. At the same time, open the gas control valve 10-2 to control the gas to enter the gas-solid suspension cavity 2 from the gas storage device 25 through the gas inlet channel 9.

[0095] Step S3: Adjust the particle supply and gas flow rate respectively through particle flow controller 26-1 and gas flow controller 26-2 so that the heat-conducting solid particles 5 and gas mixture inside the gas-solid suspension cavity 2 form a uniform gas-solid dynamic suspension state and reach a preset height, so that the heat-conducting solid particles 5 and gas mixture can completely cover the mold 15 in the cavity into which the molten metal 14 to be cooled and solidified is poured, thereby optimizing the cooling effect of the casting to be cooled and solidified.

[0096] Step S4: After the molten metal 14 to be cooled and solidified has cooled, stop the gas input and open the particle control valve 10-1 to allow the heat-conducting solid particles 5 to flow back, so that the height of the heat-conducting solid particles 5 gradually decreases until it is separated from the cooling and solidification treatment fixing device 13. Then, slowly lift the cooling and solidification treatment fixing device 13 from the gas-solid suspension chamber 2 through the lifting device 18 until the cooling and solidification treatment fixing device 13 is separated from the gas-solid suspension chamber 2. Then, take out the mold 15 from the cooling and solidification treatment fixing device 13, and finally take out the cooled and solidified casting from the mold 15 so that it can enter the subsequent processing stage.

[0097] Step S5: Rotate the lifting device 18 so that the component 22 to be heat-treated is positioned above the gas-solid suspension chamber 2; open the particle control valve 10-1 to control the thermally conductive solid particles 5 to enter the gas-solid suspension chamber 2 from the thermally conductive particle storage device 24 through the thermally conductive solid particle channel 11; at the same time, open the gas control valve 10-2 to control the gas to enter the gas-solid suspension chamber 2 from the gas storage device 25 through the gas inlet channel 9; and adjust the particle supply and gas flow rate respectively through the particle flow controller 26-1 and the gas flow controller 26-2 so that the thermally conductive solid particles 5 and the gas mixture inside the gas-solid suspension chamber 2 form a uniform gas-solid dynamic suspension state and reach a preset height, so that the thermally conductive solid particles 5 and the gas mixture can completely cover the component 22 to be heat-treated.

[0098] Step S6: According to the required heat treatment process of the component 22 to be heat treated, the target temperature in the gas-solid suspension cavity 2 is preset. The mixture of heat-conducting solid particles 5 and gas is precisely heated by the external controllable heating device 1, and the temperature of the heat-conducting solid particles 5 and gas mixture is monitored in real time by the thermocouple 4 until the temperature of the heat-conducting solid particles and gas mixture reaches the preset target temperature to achieve uniform heat transfer.

[0099] Step S7: Open the sealing cover 12, and then control the lifting device 18 to descend, slowly lowering the component 22 to be heat-treated in the heat treatment fixing device 20 to the preset height in the gas-solid suspension cavity 2, so that the component 22 to be heat-treated completely enters the gas-solid suspension cavity 2 and is immersed in the mixture of dynamically suspended heat-conducting solid particles 5 and gas, and then heat-treats it.

[0100] Step S8: After the heat treatment reaches the preset time, gradually reduce the heating power of the controllable heating device 1, and at the same time control and reduce the gas flow rate, so that the component 22 to be heat-treated gradually cools to a safe temperature range under controlled conditions; then, stop the gas input, and after the particles in the gas-solid suspension chamber 2 are reduced to the point of separation from the heat treatment fixing device 21, slowly lift the heat treatment fixing device 21 from the gas-solid suspension chamber 2 through the lifting device 18 until the heat treatment fixing device 21 is separated from the gas-solid suspension chamber 2; then remove the heat-treated component 22 from the heat treatment fixing device 21 so that it can enter the subsequent processing stage.

[0101] [Specific Implementation Example of Cooling Process]

[0102] The specific scheme of the cooling process in this application will be described in detail below using Examples 1-4 and Comparative Example 1.

[0103] [Example 1]

[0104] The cooling and solidification process of the Al9Si0.45Mg0.12Ti casting to be cooled and solidified using this gas-solid dynamic suspension casting and heat treatment temperature control device is as follows: Open the sealing cover and, using a lifting device, place the Al9Si0.45Mg0.12Ti casting, whose cross-sectional area gradually changes along its height, fixed in the cooling and solidification treatment fixing device, into the gas-solid suspension cavity; according to the structural characteristics of the casting and the height of each layer, gradually open the control valves to allow gas to enter the gas-solid suspension cavity from the gas storage device through the inlet channel, and allow the thermally conductive solid particles SiC to enter the gas-solid suspension cavity from the thermally conductive particle storage device through the thermally conductive solid particle channel, using flow control... The device precisely adjusts the gas flow rate, pressure, and flow rate of thermally conductive solid particles (SiC) to ensure that the SiC and gas mixture coats the casting layer by layer while maintaining a constant concentration of 50% at different heights. This achieves enhanced layer-by-layer cooling during the casting solidification process, improving cooling efficiency, uniformity, and reducing thermal stress. After the molten metal inside the casting has completely solidified, the gas input is stopped, and the control valve is opened to allow the SiC to flow back. Once the boiling cooling medium has descended, a lifting device is used to remove the casting, which is fixed in the cooling and solidification treatment device, from the gas-solid suspension chamber. The casting is then removed from the mold for post-processing.

[0105] The post-treatment involved applying T6 heat treatment to the casting, which included solution treatment at 500 ºC for 8 hours, hot water quenching at 70 ºC, and aging treatment at 200 ºC for 12 hours. This resulted in a high-performance Al9Si0.45Mg0.12Ti(wt%) aluminum alloy casting with a defect rate of 0.09%, a maximum defect size of 42 μm, a grain size of 26 μm, a residual stress of 6 MPa, a yield strength of 286 MPa, a tensile strength of 312 MPa, and an elongation of 8.5%.

[0106] [Example 2]

[0107] The cooling and solidification process of the Al9Si0.45Mg0.12Ti casting to be cooled and solidified using this gas-solid dynamic suspension casting and heat treatment temperature control device is as follows: Open the sealing cover and, using a lifting device, place the Al9Si0.45Mg0.12Ti casting, whose cross-sectional area gradually changes along its height, fixed in the cooling and solidification treatment fixing device into the gas-solid suspension chamber; according to the structural characteristics of the casting and the height of each layer, gradually open the control valves to allow gas to enter the gas-solid suspension chamber from the gas storage device through the inlet channel, and thermally conductive solid particles (SiC) to enter the gas-solid suspension chamber from the thermally conductive particle storage device through the thermally conductive solid particle channel; use a flow controller to precisely adjust the gas flow rate, pressure, and conductivity. The flow rate of thermally conductive solid particles SiC allows the SiC and gas mixture to coat the casting layer by layer, ensuring that the concentration of SiC and gas mixture at different heights remains constant at 70%. This achieves layer-by-layer cooling enhancement during the casting solidification process, improving cooling efficiency, enhancing cooling uniformity, and reducing thermal stress. After the molten metal inside the casting has completely solidified, the gas input is stopped, and the control valve is opened to allow the SiC to flow back. After the boiling cooling medium descends, a lifting device is used to remove the cooling and solidification treatment fixture from the gas-solid suspension chamber. Then, the mold is removed from the cooling and solidification treatment fixture, and finally, the casting is removed from the mold for post-processing.

[0108] The post-treatment involved applying T6 heat treatment to the casting, which included solution treatment at 500 ºC for 8 hours, hot water quenching at 70 ºC, and aging treatment at 200 ºC for 12 hours. This resulted in a high-performance Al9Si0.45Mg0.12Ti (wt%) aluminum alloy casting with a defect rate of 0.07%, a maximum defect size of 36 μm, a grain size of 23 μm, a residual stress of 4 MPa, a yield strength of 295 MPa, a tensile strength of 324 MPa, and an elongation of 9.6%.

[0109] [Example 3]

[0110] The cooling and solidification process of the Al9Si0.45Mg0.12Ti casting to be cooled and solidified using this gas-solid dynamic suspension casting and heat treatment temperature control device is as follows: Open the sealing cover and, using a lifting device, place the Al9Si0.45Mg0.12Ti casting, whose cross-sectional area gradually changes along its height, fixed in the cooling and solidification treatment fixing device, into the gas-solid suspension cavity; according to the structural characteristics of the casting and the height of each layer, gradually open the control valves to allow gas to enter the gas-solid suspension cavity from the gas storage device through the inlet channel, and allow the thermally conductive solid particles BN to enter the gas-solid suspension cavity from the thermally conductive particle storage device through the thermally conductive solid particle channel. The flow controller is used to precisely adjust the flow rate... The flow rate, pressure, and flow rate of thermally conductive solid particles (BN) are controlled to ensure that the BN and gas mixture coats the casting layer by layer, maintaining a constant concentration of 70% at different heights. This enhances the layer-by-layer cooling of the casting solidification process, improves cooling efficiency, enhances cooling uniformity, and reduces thermal stress. After the molten metal in the casting has completely solidified, the gas input is stopped, and the control valve is opened to allow the BN to flow back. After the boiling cooling medium descends, a lifting device is used to remove the cooling and solidification treatment fixture from the gas-solid suspension chamber. Then, the mold is removed from the cooling and solidification treatment fixture, and finally, the casting is removed from the mold for post-processing.

[0111] The post-treatment involved applying T6 heat treatment to the casting, which included solution treatment at 500 ºC for 8 hours, hot water quenching at 70 ºC, and aging treatment at 200 ºC for 12 hours. This resulted in a high-performance Al9Si0.45Mg0.12Ti (wt.%) aluminum alloy casting with a defect rate of 0.05%, a maximum defect size of 28 μm, a grain size of 16 μm, a residual stress of 3 MPa, a yield strength of 304 MPa, a tensile strength of 346 MPa, and an elongation of 13.7%.

[0112] [Example 4]

[0113] The cooling and solidification process of the Al9Si0.45Mg0.12Ti casting to be cooled and solidified using this gas-solid dynamic suspension casting and heat treatment temperature control device is as follows: Open the sealing cover and, using a lifting device, place the Al9Si0.45Mg0.12Ti casting, whose cross-sectional area gradually changes along its height, fixed in the cooling and solidification treatment fixing device, into the gas-solid suspension chamber; according to the structural characteristics of the casting and the height of each layer, gradually open the control valves to allow gas to enter the gas-solid suspension chamber from the gas storage device through the gas inlet channel, and allow the thermally conductive solid particles AlN to enter the gas-solid suspension chamber from the thermally conductive particle storage device through the thermally conductive solid particle channel; use a flow controller to precisely adjust the gas flow rate. The flow rate, pressure, and flow rate of the thermally conductive solid particles AlN are controlled to ensure that the AlN and gas mixture coat the casting layer by layer, maintaining a constant concentration of 70% at different heights. This achieves enhanced layer-by-layer cooling during the casting solidification process, improving cooling efficiency, enhancing cooling uniformity, and reducing thermal stress. After the molten metal inside the casting has completely solidified, the gas input is stopped, and the control valve is opened to allow the AlN to flow back. After the boiling cooling medium descends, a lifting device is used to remove the cooling and solidification treatment fixture from the gas-solid suspension chamber. Then, the mold is removed from the cooling and solidification treatment fixture, and finally, the casting is removed from the mold for post-processing.

[0114] The post-treatment involved applying T6 heat treatment to the casting, which included solution treatment at 500 ºC for 8 hours, hot water quenching at 70 ºC, and aging treatment at 200 ºC for 12 hours. This resulted in a high-performance Al9Si0.45Mg0.12Ti (wt.%) aluminum alloy casting with a defect rate of 0.03%, a maximum defect size of 22 μm, a grain size of 12 μm, a residual stress of 1 MPa, a yield strength of 318 MPa, a tensile strength of 374 MPa, and an elongation of 16.7%.

[0115] [Comparative Example 1]

[0116] The selected molds were all Al9Si0.45Mg0.12Ti (wt.%) aluminum alloy castings with variable cross-sectional area in the height direction, awaiting cooling and solidification. The castings underwent a conventional air solidification process, followed by a T6 heat treatment, which included a 500 ℃ solution treatment for 12 hours, a 70 ℃ hot water quenching, and a 200 ℃ aging treatment for 120 hours. This resulted in an Al9Si0.45Mg0.12Ti (wt.%) aluminum alloy casting with a defect rate of 0.65%, a maximum defect size of 1584 μm, a grain size of 125 μm, a residual stress of 46 MPa, a yield strength of 272 MPa, a tensile strength of 298 MPa, and an elongation of 1.4%.

[0117] like Figure 2The diagram shows the basic dimensions and measurement points of the castings used in Examples 1-4 and Comparative Example 1.

[0118] Table 1. Casting process parameters used in Examples 1-4 and Comparative Example 1

[0119]

[0120] Table 2. Casting parameters and mechanical properties obtained from Examples 1-4 and Comparative Example 1.

[0121]

[0122] Table 3 Mechanical properties of regions A, B, and C in Example 4 and Comparative Example 1

[0123] process Yield strength at point A (MPa) Yield strength at point B (MPa) Yield strength at point C (MPa) Tensile strength at point A (MPa) Tensile strength at point B (MPa) Tensile strength at point C (MPa) Extension rate at point A (%) Extension rate at point B (%) Point C extension rate (%) Example 4 319 315 322 372 370 376 16.7 16.5 16.9 Comparative Example 1 268 254 288 284 272 302 1.2 0.7 1.6

[0124] As shown in Tables 1, 2, and 3, the dynamic suspension of thermally conductive solid particles and gas in the castings after the cooling and solidification process of this invention significantly enhances the cooling rate during solidification and improves temperature uniformity, ensuring consistent temperature throughout the solidification process. By adjusting the pressure and flow rate of the boiling cooling medium, a consistent high cooling rate is achieved in all parts of the casting, effectively refining the grains and shortening the secondary dendrite arm spacing. This ensures a high degree of consistency in the microstructure and mechanical properties of each region of the casting, resulting in a uniformly solidified microstructure, reduced defects, and lower residual stress after solidification. Ultimately, this results in castings exhibiting lower defect rates, smaller maximum defects, finer grain sizes, lower residual stress, higher yield strength, higher tensile strength, and higher elongation, while simultaneously achieving high-performance castings with consistent mechanical properties across all regions.

[0125] [Specific Implementation Examples of the Heat Treatment Process]

[0126] The specific scheme of the heat treatment process in this application will be described in detail below using Examples 1-5 and Comparative Examples 1-5.

[0127] [Example 1]

[0128] The heat treatment process steps for Al7Si0.3Mg0.12Ti components using this gas-solid dynamic suspension casting and heat treatment temperature control device are as follows: Gas and thermally conductive solid particles are introduced through the control valve, while the gas flow rate and the supply of thermally conductive solid particles are precisely adjusted using a flow controller. This controls the mixture of thermally conductive solid particles and gas within the gas-solid suspension chamber to suspend at a specified height, ensuring complete coverage of the component. Based on the required heat treatment process for the Al7Si0.3Mg0.12Ti components, the target temperature of the gas-solid suspension chamber is pre-set to 540℃, and the holding time is set to 8 hours. The mixture of thermally conductive solid particles and gas is precisely heated using an externally controllable heating device, with thermocouples monitoring the temperature in real time until the temperature inside the solid suspension chamber reaches 540°C. The sealing cover is then opened, and the Al7Si0.3Mg0.12Ti component to be solution-treated, fixed in the heat treatment fixture, is slowly lowered to a designated height within the gas-solid suspension chamber via a lifting device, ensuring the component is completely submerged in the suspended mixture of thermally conductive solid particles and gas. During the heat treatment process, the component's temperature is monitored in real time using an infrared temperature sensor. After the preset heat treatment time of 8 hours is reached, the power of the heating device is gradually reduced, and the gas flow rate is controlled, allowing the component to gradually cool to a safe temperature range under controlled conditions. Subsequently, gas input is stopped, and after the particles in the gas-solid suspension chamber have descended, the heat treatment fixture is removed from the chamber, and the component is then removed from the fixture for subsequent processing.

[0129] [Example 2]

[0130] The heat treatment process steps for Al7Si0.3Mg0.12Ti components using this gas-solid dynamic suspension casting and heat treatment temperature control device are as follows: Gas and thermally conductive solid particles are introduced through the control valve, while the gas flow rate and the supply of thermally conductive solid particles are precisely adjusted using a flow controller. This controls the mixture of thermally conductive solid particles and gas within the gas-solid suspension chamber to suspend at a specified height, ensuring complete coverage of the component. Based on the required heat treatment process for the Al7Si0.3Mg0.12Ti components, the target temperature of the gas-solid suspension chamber is preset to 160℃, and the holding time is set to 8 hours. The mixture of thermally conductive solid particles and gas is precisely heated using an externally controllable heating device, with temperature monitored in real time by thermocouples, until the temperature inside the solid suspension chamber reaches 160°C. The sealing cover is then opened, and the Al7Si0.3Mg0.12Ti component, fixed in the heat treatment fixture and awaiting aging heat treatment, is slowly lowered to a designated height within the gas-solid suspension chamber using a lifting device, ensuring the component is completely submerged in the suspended mixture of thermally conductive solid particles and gas. During the heat treatment process, the component's temperature is monitored in real time using an infrared temperature sensor. After the preset heat treatment time of 8 hours is reached, the power of the heating device is gradually reduced, and the gas flow rate is controlled, allowing the component to gradually cool to a safe temperature range under controlled conditions. Subsequently, gas input is stopped, and after the particles in the gas-solid suspension chamber have descended, the heat treatment fixture is removed from the gas-solid suspension chamber, and then the component is removed from the heat treatment fixture for subsequent processing stages.

[0131] [Example 3]

[0132] The heat treatment process steps for Al9Si1.7Cu0.3Mg components using this gas-solid dynamic suspension casting and heat treatment temperature control device are as follows: The control valve is opened to allow gas and thermally conductive solid particles to flow in. Simultaneously, a flow controller is used to precisely adjust the gas flow rate and the supply of thermally conductive solid particles, controlling the mixture of thermally conductive solid particles and gas within the gas-solid suspension chamber to suspend at a specified height, ensuring complete coverage of the component. Based on the required heat treatment process for the Al9Si1.7Cu0.3Mg components, the initial target temperature of the gas-solid suspension chamber is preset to 500℃, and the holding time is set to 2 hours. The mixture of thermally conductive solid particles and gas is precisely heated using an externally controllable heating device, with thermocouples monitoring the temperature in real time, until the initial temperature within the solid suspension chamber reaches 500°C. The sealing cover is then opened, and the Al9Si1.7Cu0.3Mg component to be solution-treated, fixed in the heat treatment fixture, is slowly lowered to a designated height within the gas-solid suspension chamber via a lifting device, ensuring the component is completely submerged in the suspended mixture of thermally conductive solid particles and gas. During the heat treatment process, the component's temperature is monitored in real time using an infrared temperature sensor. After the preset heat treatment time of 2 hours, the power of the heating device is gradually reduced, while the gas flow rate is controlled, allowing the component to gradually cool to a safe temperature range under controlled conditions. Subsequently, gas input is stopped, and after the particles within the gas-solid suspension chamber have descended, the heat treatment fixture is removed from the chamber, and the component is then removed from the fixture for subsequent processing.

[0133] [Example 4]

[0134] The heat treatment process steps for Al9Si1.7Cu0.3Mg components using this gas-solid dynamic suspension casting and heat treatment temperature control device are as follows: Gas and thermally conductive solid particles are introduced through the control valve, while the gas flow rate and the supply of thermally conductive solid particles are precisely adjusted using a flow controller. This controls the mixture of thermally conductive solid particles and gas within the gas-solid suspension chamber to suspend at a specified height, ensuring complete coverage of the component. Based on the required heat treatment process for the Al9Si1.7Cu0.3Mg components, the initial target temperature of the gas-solid suspension chamber is preset to 530℃, and the holding time is set to 10 hours. The mixture of thermally conductive solid particles and gas is precisely heated using an externally controllable heating device, with thermocouples monitoring the temperature in real time, until the initial temperature within the solid suspension chamber reaches 530°C. The sealing cover is then opened, and the Al9Si1.7Cu0.3Mg component, fixed in the heat treatment fixture, is slowly lowered to a designated height within the gas-solid suspension chamber via a lifting device, ensuring the component is completely submerged in the suspended mixture of thermally conductive solid particles and gas. During the heat treatment process, the component's temperature is monitored in real time using an infrared temperature sensor. After the preset heat treatment time of 10 hours, the power of the heating device is gradually reduced, and the gas flow rate is controlled, allowing the component to cool gradually to a safe temperature range under controlled conditions. Subsequently, gas input is stopped, and after the particles within the gas-solid suspension chamber have descended, the heat treatment fixture is removed from the chamber, and the component is then removed from the fixture for subsequent processing.

[0135] [Example 5]

[0136] The heat treatment process steps for Al9Si1.7Cu0.3Mg components using this gas-solid dynamic suspension casting and heat treatment temperature control device are as follows: Gas and thermally conductive solid particles are introduced through the control valve, while the gas flow rate and the supply of thermally conductive solid particles are precisely adjusted using a flow controller. This controls the mixture of thermally conductive solid particles and gas within the gas-solid suspension chamber to suspend at a specified height, ensuring complete coverage of the component. Based on the required heat treatment process for the Al9Si1.7Cu0.3Mg components, the initial target temperature of the gas-solid suspension chamber is preset to 170℃, and the holding time is set to 12 hours. The mixture of thermally conductive solid particles and gas is precisely heated using an externally controllable heating device, with thermocouples monitoring the temperature in real time, until the initial temperature within the solid suspension chamber reaches 170°C. The sealing cover is then opened, and the Al9Si1.7Cu0.3Mg component, fixed in the heat treatment fixture, is slowly lowered to a designated height within the gas-solid suspension chamber via a lifting device, ensuring the component is completely submerged in the suspended mixture of thermally conductive solid particles and gas. During the heat treatment process, the component's temperature is monitored in real time using an infrared temperature sensor. After the preset heat treatment time of 12 hours is reached, the power of the heating device is gradually reduced, and the gas flow rate is controlled, allowing the component to gradually cool to a safe temperature range under controlled conditions. Subsequently, gas input is stopped, and after the particles within the gas-solid suspension chamber have descended, the heat treatment fixture is removed from the chamber, and the component is then removed from the fixture for subsequent processing.

[0137] [Comparative Example 1]

[0138] The required components are all Al7Si0.3Mg0.12Ti components, and the heat treatment process involves holding at 540℃ for 8 hours.

[0139] [Comparative Example 2]

[0140] The required components are all Al7Si0.3Mg0.12Ti components, and the heat treatment process involves holding at 160℃ for 8 hours.

[0141] [Comparative Example 3]

[0142] The required components are all Al9Si1.7Cu0.3Mg components, which are subjected to solution heat treatment at 500℃ for 2 hours.

[0143] [Comparative Example 4]

[0144] The required components are all Al9Si1.7Cu0.3Mg components, which are subjected to solution heat treatment at 530℃ for 10 hours.

[0145] [Comparative Example 5]

[0146] The required components are all Al9Si1.7Cu0.3Mg components that have undergone solution heat treatment, and are subjected to aging heat treatment at 170℃ for 12 hours.

[0147] like Figure 3 The diagram shows the basic dimensions and measurement points of the components used in Examples 1-5 and Comparative Examples 1-5.

[0148] Table 4. Comparison of heat treatment temperatures used at various locations in Examples 1-5 and Comparative Examples 1-5

[0149] process Temperature rise time (min) Temperature at location A (°C) Temperature at location B (°C) Temperature at location C (°C) Example 1 36 538 540 535 Comparative Example 1 55 543 492 462 Example 2 10 158 158 160 Comparative Example 2 20 125 135 159 Example 3 34 498 500 497 Comparative Example 3 53 462 495 487 Example 4 3 527 529 525 Comparative Example 4 10 484 497 526 Example 5 12 166 168 169 Comparative Example 5 28 140 168 152

[0150] Table 5 shows the mechanical properties of various regions in Example 2 and Comparative Example 2.

[0151] process Yield strength at point A (MPa) Yield strength at point B (MPa) Yield strength at point C (MPa) Tensile strength at point A (MPa) Tensile strength at point B (MPa) Tensile strength at point C (MPa) Extension rate at point A (%) Extension rate at point B (%) Point C extension rate (%) Example 2 164 168 170 267 264 269 5.8 5.7 5.8 Comparative Example 2 152 172 164 270 247 256 6.0 5.2 5.5

[0152] As shown in Tables 4 and 5, the components after the heat treatment process of this invention, by dynamically suspending thermally conductive solid particles and gas in the heating chamber, can not only achieve rapid heating of the heat-treated components and shorten the heat treatment time, but also overcome the problem of uneven temperature in traditional heat treatment, achieve uniform temperature distribution, obtain a uniform heat-treated microstructure and heat-treated components with consistent mechanical properties in each region, and greatly enhance the consistency of microstructure and mechanical properties in each region of the component.

[0153] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. Casting and heat treatment temperature control device based on gas-solid dynamic suspension, comprising a gas-solid suspension cavity (2), the top of the gas-solid suspension cavity (2) is provided with a sealing cover plate (12); the outside of the gas-solid suspension cavity (2) is provided with a controllable heating device (1), the inside of the gas-solid suspension cavity (2) is uniformly filled with a mixture of heat-conducting solid particles (5) and gas; The inner wall of the gas-solid suspension cavity (2) is provided with an infrared temperature sensor (3) and a thermocouple (4), a heat-conducting solid particle channel (11) is connected between the bottom of the gas-solid suspension cavity (2) and a heat-conducting particle storage device (24), a particle control valve (10-1) and a particle flow controller (26-1) are installed on the heat-conducting solid particle channel (11); The bottom of the gas-solid suspension cavity (2) is provided with a gas shunt device (8) and an air inlet channel (9), the inside of the gas shunt device (8) is provided with a buffer cavity, and the buffer cavity is in communication with the inside of the gas-solid suspension cavity (2) through a plurality of shunt flow channels, the gas shunt device (8) is connected with a gas storage device (25) through the air inlet channel (9), and a gas control valve (10-2) and a gas flow controller (26-2) are installed on the air inlet channel (9); The temperature control processing device is arranged on the top of the base (7), one side of the base (7) is provided with a lifting column (6) and a lifting device (18), wherein the lifting device (18) can move up and down along the lifting column (6) and can rotate around the lifting column (6); One side of the lifting device (18) is connected with a first cross beam (17), the bottom of the first cross beam (17) is connected with a cooling and solidification processing fixing device (13) through a matching device (16), the bottom of the cooling and solidification processing fixing device (13) is provided with a plurality of porous channels, the inside of the cooling and solidification processing fixing device (13) is fixed with a casting mold (15), and the casting mold (15) is poured with a to-be-cooled and solidified metal melt (14) in a cavity thereof; The other side of the lifting device (18) is connected with a second cross beam (19); a heat treatment fixing device (21) is connected below the second cross beam (19) through a rope (20), a plurality of porous channels are arranged around the heat treatment fixing device (21), and a to-be-heat-treated component (22) is fixed in the heat treatment fixing device (21); Characterized in that: The cooling and solidification processing fixing device (13) and the casting mold (15) are fixed by wedge-shaped matching; the bottom of the heat treatment fixing device (21) is provided with an elastic clamping structure (23) for fixing the to-be-heat-treated component (22); The infrared temperature sensor (3) is uniformly distributed layer by layer in the gas-solid suspension cavity (2) to monitor and feedback the temperature of each layer of the to-be-cooled and solidified metal melt in the heat treatment component and the casting mold in real time; the thermocouple (4) is arranged at the bottom of the infrared temperature sensor (3) in the gas-solid suspension cavity (2) to monitor the temperature of the mixture of heat-conducting solid particles (5) and gas in real time, so as to determine whether the preset temperature is reached. The heat-conducting solid particles (5) can flow out of the heat-conducting particle storage device (24) and flow into the heat-conducting particle storage device (24) through the particle control valve (10-1); the flow and pressure of the heat-conducting solid particles (5) in the heat-conducting solid particle channel (11) are controlled through the particle flow controller (26-1); The gas can flow out of the gas storage device (25) through the gas control valve (10-2); the flow and pressure of the gas in the gas inlet channel (9) are controlled through the gas flow controller (26-2); The control priority of the gas control valve (10-2) is higher than that of the particle control valve (10-1); the control priority of the gas flow controller (26-2) is higher than that of the particle flow controller (26-1); When the input gas is controlled through the gas control valve (10-2) and the gas flow controller (26-2), the control priority of the gas pressure is higher than that of the gas flow, and the control priority of the gas flow is higher than that of the input gas time; The mass of the heat-conducting solid particles (5) in the gas-solid suspension cavity (2) satisfies the following formula: M 补 = K1 x Q 气 x p 固 x t Wherein, M 补 Mass of particles to be replenished, kg; K1 is a coefficient related to the density characteristics of the heat-conducting solid particles, and the value thereof is determined according to the density of the heat-conducting solid particles; Q 气 Flow rate, m3 / s; p 固 p density of the heat-conducting solid particles in the gas-solid suspension cavity, kg / m3; t is the time of the input gas, s; The height of the mixture of the heat-conducting solid particles (5) and the gas in the gas-solid suspension cavity (2) satisfies the following formula: H=K2×P / P0×h+H0 Wherein, H is the height of the mixture of the heat-conducting solid particles (5) and the gas, mm; K2 is a coefficient related to the density characteristics of the heat-conducting solid particles, and the value thereof is determined according to the density of the heat-conducting solid particles; P is the gas pressure of the input gas, bar; P0 is a reference value selected for non-dimensionalization, P0=1bar; h is a reference value selected for converting the gas pressure into the height, h=1mm; H0 is the initial height of the mixture of the heat-conducting solid particles (5) and the gas, mm.

2. The gas-solids dynamic suspension based casting and heat treatment temperature control apparatus according to claim 1, wherein: The heating element of the controllable heating device (1) is selected from at least one or a combination of multiple kinds of iron-chromium-aluminum wire, molybdenum wire and tungsten wire.

3. The gas-solids dynamic suspension based casting and heat treatment temperature control apparatus as claimed in claim 1, wherein: The heat-conducting solid particles (5) are selected from at least one or a combination of multiple kinds of carbon, graphite, diamond, aluminum nitride, silicon nitride, boron nitride, silicon carbide, carbon nanotube, graphene, magnesium oxide, aluminum oxide, zinc oxide, silicon dioxide, gold, silver, copper, aluminum, magnesium, iron and stainless steel.

4. The gas-solids dynamic suspension based casting and heat treatment temperature control apparatus as claimed in claim 1, wherein: The gas medium in the gas storage device (25) is selected from at least one or a mixture of multiple kinds of water vapor, compressed air, nitrogen, hydrogen, oxygen, carbon dioxide, argon, neon, helium, krypton and xenon, and the gas medium is selected from a gas after being refrigerated or heated.

5. The control method of the gas-solid dynamic suspension based casting and heat treatment temperature control apparatus according to any one of claims 1 to 4, characterized by: The method comprises the following steps: Step S1: Rotate the lifting device (18) so that the mold (15) with the molten metal (14) to be cooled and solidified is located above the gas-solid suspension cavity (2); open the sealing cover plate (12), then control the lifting device (18) to lower, slowly lower the mold (15) with the molten metal (14) to be cooled and solidified in the mold cavity fixed in the cooling and solidification treatment fixing device (13) to a preset height in the gas-solid suspension cavity (2), so that the mold (15) with the molten metal (14) to be cooled and solidified in the mold cavity completely enters the inside of the gas-solid suspension cavity (2); Step S2: According to the structural characteristics of the mold (15) with the molten metal (14) to be cooled and solidified in the mold cavity, open the particle control valve (10-1), control the heat-conducting solid particles (5) to enter the inside of the gas-solid suspension cavity (2) from the heat-conducting particle storage device (24) through the heat-conducting solid particle channel (11), and at the same time, open the gas control valve (10-2), control the gas to enter the inside of the gas-solid suspension cavity (2) from the gas storage device (25) through the gas inlet channel (9); Step S3: Adjust the particle supply amount and gas flow rate by the particle flow controller (26-1) and the gas flow controller (26-2) respectively, so that the mixture of heat-conducting solid particles (5) and gas in the gas-solid suspension cavity (2) forms a uniform gas-solid dynamic suspension state and reaches a preset height, so that the mixture of heat-conducting solid particles (5) and gas can completely cover the mold (15) with the molten metal (14) to be cooled and solidified in the mold cavity; Step S4: After the molten metal (14) to be cooled and solidified is cooled and solidified, stop the input of gas and open the particle control valve (10-1) to make the heat-conducting solid particles (5) flow back, so that the height of the heat-conducting solid particles (5) gradually decreases, until it is lowered to separate from the cooling and solidification treatment fixing device (13), then slowly lift the cooling and solidification treatment fixing device (13) from the gas-solid suspension cavity (2) by the lifting device (18) until the cooling and solidification treatment fixing device (13) is separated from the gas-solid suspension cavity (2); then take out the mold (15) from the cooling and solidification treatment fixing device (13), and finally take out the cooled and solidified casting from the mold (15); Step S5: Rotate the lifting device (18) so that the component to be heat treated (22) is located above the gas-solid suspension cavity (2); open the particle control valve (10-1) to control the heat-conducting solid particles (5) from the heat-conducting particle storage device (24) to enter the gas-solid suspension cavity (2) through the heat-conducting solid particle channel (11), and at the same time, open the gas control valve (10-2) to control the gas from the gas storage device (25) to enter the gas-solid suspension cavity (2) through the gas inlet channel (9), and adjust the particle supply amount and gas flow rate through the particle flow controller (26-1) and the gas flow controller (26-2) respectively, so that the mixture of heat-conducting solid particles (5) and gas in the gas-solid suspension cavity (2) forms a uniform gas-solid dynamic suspension state and reaches a preset height, so that the mixture of heat-conducting solid particles (5) and gas can completely cover the component to be heat treated (22); Step S6: According to the required heat treatment process requirements of the component to be heat treated (22), the target temperature in the gas-solid suspension cavity (2) is preset, the mixture of heat-conducting solid particles (5) and gas is precisely heated by the external controllable heating device (1), and the temperature of the mixture of heat-conducting solid particles (5) and gas is monitored in real time by the thermocouple (4), until the temperature of the mixture of heat-conducting solid particles and gas reaches the preset target temperature; Step S7: Open the sealing cover plate (12), then control the lifting device (18) to descend, slowly lower the component to be heat treated (22) fixed in the heat treatment fixing device (21) to the preset height in the gas-solid suspension cavity (2), so that the component to be heat treated (22) completely enters the inside of the gas-solid suspension cavity (2) and is immersed in the mixture of dynamically suspended heat-conducting solid particles (5) and gas, and then heat treatment is performed; Step S8: When the heat treatment reaches the preset time, gradually reduce the heating power of the controllable heating device (1), and at the same time, control the gas flow rate to gradually cool the component to be heat treated (22) to a safe temperature range under controlled conditions; then, stop the gas input, after the particles in the gas-solid suspension cavity (2) are reduced to separate from the heat treatment fixing device (21), the heat treatment fixing device (21) is slowly lifted from the gas-solid suspension cavity (2) by the lifting device (18) until the heat treatment fixing device (21) is separated from the gas-solid suspension cavity (2); then the heat-treated component to be heat treated (22) is taken out from the heat treatment fixing device (21).

Images