Semi-solid metal pressure quenching device and method

Abstract

According to the pressure quenching device and method for the semi-solid metal, in the quenching operation stage, pressure is applied to a semi-solid metal workpiece, cooling is conducted synchronously, and therefore the semi-solid metal workpiece is prevented from generating cracks in the quenching process. Comprising a pressure applying component which is arranged to apply circumferential pressure and / or axial pressure to a semi-solid metal workpiece; and the heat exchange component is integrated with the pressure applying component and is used for cooling the workpiece while the pressure applying component applies pressure to the workpiece. The invention further discloses a pressure quenching method which comprises a synchronous pressure applying and cooling step: applying at least one of pressure in the circumferential direction and pressure in the axial direction to the workpiece, and eliminating the time sequence difference between cooling and pressurizing by establishing heat exchange between the heat exchange component and the surface of the workpiece at the pressurizing starting moment. And external force is applied while cooling, so that the volume shrinkage in the liquid phase solidification process in the workpiece can be fed, and the workpiece is prevented from generating cracks in the quenching process.

Description

Technical Field

[0001] This invention relates to the field of non-ferrous metal alloy manufacturing, and more specifically, to processing alloys under semi-solid conditions. Background Technology

[0002] Based on their solid or solid-liquid mixed state characteristics, alloys are classified into solid alloys and semi-solid metals. Solid alloys refer to solid substances with metallic properties formed after the combination of two or more metals, or metals and non-metals, through melting, sintering, or other methods, followed by cooling and solidification. Atoms in the solid state form an ordered or disordered arrangement, distinguishing them from liquid or semi-solid metals. Semi-solid metals refer to slurries or billets where the solidification process is controlled by special techniques, resulting in a coexistence of solid and liquid phases. The liquid phase volume fraction is typically 5%–60%, with solid particles uniformly dispersed within the liquid phase, exhibiting characteristics of both solid and liquid states.

[0003] Semi-solid metal forming, achieved through a solid-liquid mixture, represents a significant innovative technology in metal processing. Preparation methods for semi-solid metals include rheological forming and thixotropic forming. Rheological forming involves applying electromagnetic or mechanical stirring to the melt as it cools to the semi-solid region, breaking down dendrites to form a spherical solid slurry. Thixotropic forming involves reheating a pre-prepared solid alloy ingot to the semi-solid temperature range. It offers high process compatibility, suitable for various processing methods such as casting, extrusion, and forging. Semi-solid formed parts are used in the automotive and aerospace industries, offering significant weight reduction, excellent heat dissipation, and higher tensile strength than traditional castings.

[0004] In existing technologies, metal processing is mostly designed for traditional solid metals, lacking consideration for the special needs of semi-solid materials. Summary of the Invention

[0005] The inventors of this invention discovered that in traditional semi-solid metals, the liquid phase accounts for approximately 40%–60%, and the smelted billets are directly formed using methods such as forging, extrusion, drawing, and stamping. It is important to note that semi-solid metals with a liquid phase content of approximately 40%–60% possess fluidity in their liquid state; therefore, there is no issue of billet cracking during the process, and there is no technological inspiration to address cracking in semi-solid metals through pressure.

[0006] Semi-solid metals, with approximately 40%–60% liquid phase, are designed to overcome the defects in solid metal forming. The biggest problem with solid metals is their poor plasticity and high deformation resistance. Forming requires "high temperature, high pressure, and multiple processing steps", making it difficult to directly manufacture complex shapes. In contrast, the liquid matrix in semi-solid slurry acts as a lubricant, reducing friction between solid particles and allowing it to flow rapidly under shear force. This allows the material to fill complex mold cavities under low pressure of 10-50MPa, and even achieve one-time forming. Solid metals have a strong tendency to inherit defects. If the original billet contains porosity or shrinkage, subsequent solid-state processing is difficult to eliminate and may even amplify the defects. Solid metal processing involves long processes, high energy consumption, and low material utilization, resulting in high overall costs. Semi-solid metals achieve cost reduction and efficiency improvement through "near-net-shape forming and short processes".

[0007] It is evident that semi-solid metals, traditionally composed of approximately 40%–60% liquid phase, primarily aim to solve problems that solid metals cannot address, especially when manufacturing complex-shaped, high-performance, and highly reliable metal parts at a lower cost. In such cases, the properties of semi-solid metals far surpass those of solid metals. In contrast, traditional stress hardening, which is applied to solid metals, provides no compensation for shrinkage as the volume of the solid metal remains almost unchanged after hardening.

[0008] The inventors of this invention also discovered that in a micron-sized semi-solid metal, the liquid phase accounts for approximately 5%–10%. When the liquid phase percentage is 5%–10%, during the quenching and cooling process of high-solid-phase semi-solid metal materials, the residual liquid phase distributed at the solid grain boundaries undergoes rapid solidification and solidification shrinkage. However, due to the high solid phase fraction, the resulting rigid solid skeleton greatly restricts the flow capacity of the remaining liquid phase, preventing effective filling of the voids generated by solidification shrinkage, thus forming micro-shrinkage porosity and cavities. Simultaneously, the enormous thermal and structural stresses generated during the quenching process are highly concentrated at these defects, causing microcracks to initiate and further expand and interconnect, ultimately leading to macroscopic cracking of the workpiece, affecting product performance and reliability. This has become a key technological challenge restricting the performance improvement and application expansion of high-solid-phase semi-solid metal materials.

[0009] The inventors of this invention also discovered that applying pressure while cooling high-solid-phase semi-solid metal materials during quenching can effectively prevent crack formation, but crack formation cannot be suppressed when cooling and pressurization are not synchronized.

[0010] When cooling precedes pressurization, micro-shrinkage and cavities have already formed, and the rigid framework is fully established. Applying pressure at this point will cause stress to concentrate extremely at the tips of these existing defects. This not only fails to achieve effective shrinkage compensation but also directly promotes the initiation and rapid propagation of microcracks from the defects, leading to workpiece cracking.

[0011] When pressure is applied before cooling, the pressure cannot be applied during the crucial solidification shrinkage moment. The material remains under tensile stress, and the risk of cracking remains high. The pressure's "compensation" window is missed.

[0012] To solve the above technical problems, the inventor proposes a pressure quenching device for semi-solid metals, comprising: a pressure applying component configured to apply circumferential pressure and / or axial pressure to a semi-solid metal workpiece, where the magnitudes P of the circumferential pressure and the axial pressure are respectively 0 < P < 100 MPa; a heat exchange component integrated with the pressure applying component for cooling down the workpiece while the pressure applying component applies pressure to the workpiece.

[0013] In a preferred embodiment, the heat exchange component comprises: a medium circulation tank for storing and regulating a cooling medium; a circulation pump whose inlet is connected to the medium circulation tank; a medium accommodation cavity disposed inside the pressure applying component; a medium inlet pipe connecting the outlet of the circulation pump to the inlet of the medium accommodation cavity; and a medium outlet pipe connecting the outlet of the medium accommodation cavity to the medium circulation tank.

[0014] In a preferred embodiment, the medium accommodation cavity is an integral cavity disposed inside the pressure applying component.

[0015] In a preferred embodiment, the medium accommodation cavity is a distributed cooling flow channel.

[0016] In a preferred embodiment, the medium accommodation cavity is a serpentine flow channel.

[0017] In a preferred embodiment, the medium accommodation cavity is a parallel arrangement of flow channels.

[0018] In a preferred embodiment, the medium accommodation cavity is a multi-layer mesh flow channel.

[0019] In a preferred embodiment, the cross-sectional shape and size of the distributed cooling flow channel include but are not limited to circular, trapezoidal, rectangular, U-shaped, or parabolic, etc.

[0020] In a preferred embodiment, before the start of the pressurization operation, the medium accommodation cavity and the pipelines connected thereto are pre-filled with a cooling medium.

[0021] In a preferred embodiment, the heat exchange component includes heat pipes, and the working surface of the heat pipes is flush with the pressure applying surface of the pressure applying component to synchronously contact the workpiece surface during pressurization.

[0022] In a preferred embodiment, the pressure applying component is provided with a fixing groove, the heat pipes are embedded in the fixing groove, and the gap between the fixing groove and the heat pipes is filled with a filler, and the filler includes thermal grease, thermal adhesive, solder, or thermal silica gel.

[0023] In a preferred embodiment, the heat pipes include: an evaporation section that directly contacts the workpiece and is embedded in the pressure applying component; a condensation section that extends outward from the side surface of the pressure applying component; or, there are channels inside the pressure applying component, and the condensation section extends outward through the channels.

[0024] In a preferred embodiment, the shape of the pressure-applying surface of the pressure-applying component matches the surface of the workpiece.

[0025] In a preferred embodiment, the pressure-applying component is configured to surround part or all of the surface of the workpiece.

[0026] In a preferred embodiment, the pressure application component is driven by a manual or electric device to apply pressure.

[0027] A method for pressure quenching of semi-solid metal includes the following steps: Synchronous pressure cooling step: Apply at least one of the circumferential and axial pressures to the workpiece, and establish heat exchange with the workpiece surface through the heat exchange component at the moment of pressurization, eliminating the time difference between cooling and pressurization.

[0028] In a preferred embodiment, the pressure applied to the workpiece is from 0.1 MPa to 30 MPa, and the cooling temperature is from 10°C to 100°C.

[0029] In a preferred embodiment, the cooling temperature is 20°C-80°C.

[0030] In a preferred embodiment, the semi-solid metal is a magnesium alloy / aluminum alloy.

[0031] In a preferred embodiment, the semi-solid metal is a magnesium / aluminum alloy with a liquid phase content of 5%-10%.

[0032] In a preferred embodiment, the semi-solid metal is a magnesium alloy / aluminum alloy rod with a liquid phase content of 5-10%.

[0033] The beneficial effects of the embodiments of the present invention are as follows: During the solidification process of semi-solid metal, the solid phase particles are further arranged in a tighter manner, and the liquid phase fills the gaps to form a dense structure. This is usually accompanied by volume shrinkage. Applying external force while cooling can compensate for the volume reduction of the semi-solid metal workpiece. It can compensate for the volume shrinkage during the solidification process of the liquid phase in the semi-solid metal workpiece, and the arrangement of the structure is more compact, thereby avoiding cracks in the semi-solid metal during the quenching process.

[0034] By integrating the heat exchange components and the pressure application components into one unit, instantaneous synchronization of pressure application and cooling is achieved. When the device comes into contact with the workpiece, pressure and cooling act simultaneously: the external pressure immediately compensates for the shrinkage at the moment of solidification contraction, while the heat pipe continuously removes the latent heat of solidification at a high rate of phase change heat transfer, ensuring unobstructed liquid phase backfilling channels, thereby suppressing the generation of shrinkage cavities and microcracks from the source.

[0035] Compared to the feeding lag caused by pressure transmission delay or uneven cooling in traditional pressure quenching, this solution combines the force transmission path and the heat transfer path into one, enabling the mechanical response and thermal response to be synchronized in milliseconds, which significantly improves the density of the microstructure.

[0036] Under this synchronous action, the semi-solid metal can undergo coordinated micro-plastic deformation at the solidification front, effectively releasing local stress concentration. At the same time, the rapid heat dissipation of the heat pipe inhibits the formation of brittle phases, further blocking the crack propagation path. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of a pressure quenching device for semi-solid metal in an embodiment of the present invention; Figure 2 This is a side view of the pressure application component in an embodiment of the present invention; Figure 3 This is a schematic diagram of the pressure application component in an embodiment of the present invention; Figure 4 This is a schematic diagram of the integral media receiving cavity in an embodiment of the present invention; Figure 5 , Figure 6 This is a schematic diagram of a distributed media containment cavity in an embodiment of the present invention; Figure 7 This is a schematic diagram of a pressure quenching device for semi-solid metal in another embodiment of the present invention; Figure 8 This is an enlarged view of the fixing groove for accommodating the heat pipe in another embodiment of the present invention; Figure 9 This is a cross-sectional view of a pressure quenching device for semi-solid metals in another embodiment of the present invention; Figure 10 - Figure 15 This is a schematic diagram of the pressure quenching device for semi-solid metals in an embodiment of the present invention; Figure 16 - Figure 24 This is a schematic diagram of the layout of the pressure application component in an embodiment of the present invention.

[0038] Figure label: Workpiece 1, pressure applying component 2, circumferential pressure applying component 21, axial pressure applying component 22, medium receiving cavity 23, inlet 231, outlet 232, heat exchange component 3, medium circulation tank 31, circulation pump 32, medium inlet pipe 321, medium outlet pipe 322, fixing groove 24, heat dissipation fins 25, channel 26, heat pipe 33, evaporation section 332, condensation section 333, filler 331, circumferential pressure F1, axial pressure F2. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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, not all, of the embodiments of the present invention. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0040] In this application, "axial" refers to the direction parallel to the main axis of the semi-solid metal workpiece (hereinafter referred to as "workpiece"), and "circumferential" refers to the direction surrounding the main axis of the workpiece. Example

[0041] Please refer to Figures 1 to 3 The pressure quenching device disclosed in this embodiment of the invention mainly consists of a pressure application component 2 and a heat exchange component 3.

[0042] The pressure applying component 2 is arranged around the workpiece 1 and is the execution module that directly applies circumferential pressure F1 and / or axial pressure F2 to the workpiece 1. In one example, the pressure applying component 2 includes a circumferential pressure applying component 21, which directly contacts the surface of the workpiece 1 when quenching pressure is applied to apply circumferential pressure F1 to the workpiece 1. In another example, the pressure applying component 2 includes an axial pressure applying component 22, which directly contacts the surface of the workpiece 1 when quenching pressure is applied to apply axial pressure F2 to the workpiece 1. In yet another example, the pressure applying component 2 includes a circumferential pressure applying component 21 and an axial pressure applying component 22, which directly contact the surface of the workpiece 1 when quenching pressure is applied to apply circumferential pressure F1 and axial pressure F2 to the workpiece 1 synchronously or asynchronously.

[0043] The pressure application component 2 has a media receiving cavity 23 machined inside, which serves as a key area for heat exchange. The heat exchange component 3 includes a media circulation tank 31 and a circulation pump 32. The circulation pump 32 serves as a power source, and its inlet is directly or indirectly connected to the media circulation tank 31. Its outlet is connected to the inlet 231 of the media receiving cavity 23 inside the pressure application component 2 through a media inlet pipe 321. The outlet 232 of the receiving cavity is then connected to the media circulation tank through a media outlet pipe 322, thereby forming a complete closed cooling circuit.

[0044] Please refer to Figure 1 , Figure 4In one example, the medium-containing cavity 23 is an integral cavity disposed inside the pressure-applying component 2. The integral cavity structure is robust, has strong pressure-bearing capacity, is relatively simple to manufacture, and has low manufacturing cost; please refer to... Figure 5 , Figure 6 In another example, the medium receiving cavity 23 is configured as a distributed cooling channel to accommodate a more flexible design.

[0045] Specifically, the layout of distributed cooling channels includes, but is not limited to, serpentine, parallel, multi-layered mesh, or other topological structures adapted to the shape of the workpiece. The cross-sectional shape and size of the distributed cooling channels include, but are not limited to, circular, trapezoidal, rectangular, U-shaped, or parabolic shapes. The layout, cross-sectional shape, and size of the distributed cooling channels are selected and optimized based on actual heat dissipation requirements, space constraints, and manufacturing processes. It should be understood that any variation in channel morphology based on the core concept of setting up a channel network within the pressure-applying component to achieve synchronous pressurization and cooling should be considered to fall within the protection scope of this invention.

[0046] In one example, the medium inlet pipe 321 and the medium outlet pipe 322 are made of flexible pressure-resistant hoses. These flexible hoses effectively compensate for installation alignment errors and absorb mechanical vibrations, making them suitable for complex piping spaces. In another example, the medium inlet pipe 321 and the medium outlet pipe 322 are made of rigid metal pipes, suitable for fixed piping systems requiring high stability.

[0047] During the quenching process, the pressure applying component 2 pressurizes the workpiece 1. Simultaneously, the circulating pump 32 starts, driving the cooling medium to flow from the medium circulation tank 31 and into the medium receiving chamber 23 inside the pressure applying component 2 via the medium inlet pipe 321. The cooling medium includes, but is not limited to, water, water-glycol solution, special quenching oil, or high-temperature heat transfer oil. In one example, the temperature of the cooling medium is 10℃-100℃, and in another example, the temperature of the cooling medium is 20℃-80℃. As the medium flows through the medium receiving chamber 23, it rapidly absorbs the heat conducted from the workpiece 1 to the pressure applying component 2. Subsequently, the heated medium returns to the medium circulation tank 31 via the medium outlet pipe 322 for cooling, thus completing one cycle.

[0048] In one optimized example, a pre-filling scheme was employed: the medium receiving chamber 23 and part of the piping were pre-filled with cooling medium before the pressurization process began. This allows the cooling medium to exchange heat with the workpiece 1 with "zero delay" immediately upon pressure build-up, without experiencing the delay of filling the piping. During the quenching operation, the cooling medium rapidly absorbs the heat conducted from the workpiece, and then the heated medium is continuously pushed by the pumped-out cold medium, returning to the circulation tank through the medium outlet pipe for cooling, thus forming a dynamic cycle that continuously removes heat.

[0049] This design achieves spatial and temporal unification of the pressure and temperature fields by directly integrating the key areas of the heat exchange component 3 into the pressure application component 2. Its technical advantages lie in the fact that the pressure acting on the instant of solidification shrinkage effectively compensates for liquid phase shrinkage, suppressing the formation of micro-shrinkage and cavities at the source; while simultaneous uniform cooling refines grains and reduces thermal stress. The synergy of these two factors fundamentally solves the problem of workpiece deformation and cracking caused by asynchronous cooling and pressurization, significantly improving the density and mechanical properties of the product. Example

[0050] This embodiment discloses a pressure quenching device for semi-solid metals, wherein the heat exchange component 3 is a heat pipe 33. Please refer to... Figure 7 The pressure applying components include a circumferential pressure applying component 21 and an axial pressure applying component 22. The circumferential pressure applying component 21 and the axial pressure applying component 22 are in direct contact with the surface of the workpiece 1 when pressure is applied, so as to apply circumferential pressure F1 and axial pressure F2 to the workpiece 1.

[0051] Please refer to Figure 7 , Figure 8 The side of the pressure applying component 2 that contacts the workpiece 1 is provided with a fixing groove 24 that is recessed away from the contact surface of the workpiece to accommodate the heat pipe 33. The working surface of the heat pipe 33 that contacts the workpiece 1 is flush with the pressure applying surface of the pressure applying component 2 that contacts the workpiece 1. The "working surface" of the heat pipe refers to the area that is used to directly contact the surface of the workpiece and exchange heat.

[0052] When quenching a semi-solid metal workpiece 1, the pressure applying component 2 contacts the surface of the workpiece 1 and applies pressure; at the same time, the heat pipe 33 integrated in the pressure applying component 2 also contacts the surface of the workpiece 1 and rapidly absorbs its heat.

[0053] Heat is conducted to the pressure application component 2 through the efficient heat conduction of heat pipe 33, and then dissipated outwards. This embodiment, through the above structure, ensures instantaneous synchronization between pressure application and cooling, eliminating the time lag between cooling and pressurization. This synchronicity allows the semi-solid metal workpiece to complete a phase transformation under continuous pressure, effectively offsetting thermal stress and significantly reducing the risk of crack formation.

[0054] Please refer to Figure 9 This is a cross-sectional view of the heat pipe 33 and the pressure applying component 2. The side of the pressure applying component 2 that contacts the workpiece 1 is provided with a fixing groove 24 that is recessed away from the workpiece contact surface, and the heat pipe 33 is accommodated in the fixing groove 24.

[0055] In one example, the gap between the mounting groove 24 and the heat pipe 33 is filled with filler 331. Filler 331 includes, but is not limited to, high-performance thermally conductive materials such as thermal grease, thermal adhesive, solder, or thermal silicone, and its function is to secure the heat pipe 33 within the mounting groove 24 without gaps. This improves the overall structural stability of the component under mechanical vibration and impact, thereby enhancing mechanical adhesion. Furthermore, filler 331 eliminates air between the interfaces, reducing the contact thermal resistance between the heat pipe 33 and the pressure application component 2, thus creating an efficient heat flow channel and optimizing thermal performance.

[0056] In one example, heat dissipation fins 25 are provided on the side of the pressure applying component 2 away from the workpiece, and are arranged at predetermined intervals on the upper surface of the pressure applying component 2 along the length direction of the workpiece 1. The lower ends of the heat dissipation fins 25 are fixed to the pressure applying component 2 by adhesive or solder. The arrangement of the heat dissipation fins 25 can increase the heat dissipation area and further improve the heat dissipation efficiency.

[0057] The specific layout and quantity design of the fixing slot 24 and the heat pipe 33 are essentially a preferred means to achieve efficient integration of the heat pipe 33 and the pressure application component 2, with the fundamental purpose of ensuring the reliable realization of the "synchronous pressurization and cooling" function. Therefore, under the concept of this invention, the position and quantity of the fixing slot 24 and the heat pipe 33 are not fixed, but can be adaptively adjusted according to the actual heat dissipation requirements, the shape of the workpiece, and the structure of the pressure application component.

[0058] For example, for areas requiring focused cooling or irregularly shaped workpieces, multiple or specifically shaped fixing grooves 24 and heat pipes 33 can be specifically designed; conversely, for workpieces with uniform cooling requirements, a series of regularly arranged fixing grooves 24 can be arranged along their length. The key is that, regardless of the specific implementation of the fixing grooves 24 and heat pipes 33, their design must ensure that: during the quenching operation of workpiece 1, the pressure applying component 2 contacts the surface of workpiece 1 and applies pressure; simultaneously, the heat pipes 33 integrated within the pressure applying component 2 can also effectively contact the surface of workpiece 1 and rapidly absorb its heat. As long as this core function is met, any design changes to the fixing grooves based on actual needs fall within the flexible protection scope advocated by this invention. Example

[0059] Please refer to Figure 10 In this embodiment, the heat pipe 33 includes an evaporation section 332 and a condensation section 333. The evaporation section 332 is embedded within the pressure applying component 2 and is in direct contact with the workpiece 1, with its surface flush with the surface of the pressure applying component 2. The condensation section 333 extends away from the workpiece. In this embodiment, heat is rapidly transferred from the workpiece 1 to the evaporation section 332 of the heat pipe, and then transferred to the condensation section 333 by the phase change of the working fluid inside the heat pipe 33, forming a heat transfer path.

[0060] In this heat transfer path, heat is rapidly absorbed from the surface of workpiece 1 to the evaporation section 332, which then triggers a liquid-gas phase change in the working fluid inside the heat pipe 33. The gaseous working fluid, carrying latent heat, rapidly flows to the condensation section 333, where it releases heat and re-condenses into a liquid. It then flows back to the evaporation section 332 through the capillary structure, completing a highly efficient energy transfer cycle.

[0061] Please refer to Figure 10 , Figure 11 In one example, the condensation section 333 extends from one side of the pressure-applying component 2 away from the workpiece 1. Please refer to... Figure 12 , Figure 13 In another example, the condensation section 333 extends from both sides of the pressure-applying component 2 in a direction away from the workpiece 1. Please refer to... Figure 14 , Figure 15 In another example, the pressure applying component 2 has a channel 26 inside, and the condensation section 333 extends outward through the channel 26.

[0062] All the above layouts increase the heat dissipation area by providing heat dissipation fins 25 on the condensation section 333. In one example, the heat dissipation fins 25 are installed as a separate component; in another example, the heat dissipation fins 25 are fixedly connected to the pressure application component 2 or the body of the condensation section 333.

[0063] To achieve a uniform and stable pressure and cooling field for workpiece 1, this invention provides various layout schemes for pressure application components, such as... Figures 16 to 24 As shown.

[0064] Please refer to Figure 16 , Figure 17 , Figure 18 The circumferential pressure applying components 21 are symmetrically arranged on both sides of the workpiece 1, which is cylindrical. To match the shape of the workpiece 1, the two circumferential pressure applying components 21 are designed in an arc shape to provide circumferential pressure F1 to the workpiece 1. The symmetrical design helps to establish a uniform pressure field and cooling field around the workpiece. It can effectively prevent internal stress, uneven structure, and crack initiation caused by uneven cooling or pressure. In one example, the circumferential pressure applying components 21 are arranged around the workpiece left and right, and in another example, they are arranged vertically. When pressure is applied to the workpiece, the side of the circumferential pressure applying component 21 that contacts the workpiece 1 can fit tightly against the workpiece 1.

[0065] Please refer to Figure 19 , Figure 20 , Figure 21 In one example, three circumferential pressure applying components 21 are arranged around the workpiece 1. The specific position and size of each circumferential pressure applying component 21 are adjusted according to different operational requirements. When pressure is applied to the workpiece, the circumferential pressure applying components 21 are in close contact with the workpiece surface.

[0066] Please refer to Figures 22 to 24 In one example, four circumferential pressure applying components 21 are set around the workpiece 1, and the specific position and size of each circumferential pressure applying component 21 are adjusted according to different operation requirements.

[0067] In one example, the workpiece 1 is rod-shaped, and the surface of the circumferential pressure applying component 21 that contacts the workpiece 1 is designed to be arc-shaped; in another example, the workpiece 1 is column-shaped, and the surface of the circumferential pressure applying component 21 that contacts the workpiece 1 is designed to be square. It should be understood that the surface of the circumferential pressure applying component 21 that contacts the workpiece 1 is designed to match the shape of the surface of the workpiece 1 under pressure, so as to ensure that when pressure is applied to the workpiece, the circumferential pressure applying component 21 fits tightly against the surface of the workpiece 1.

[0068] Similarly, the size, number, shape, and position of the axial pressure application component 22 can also be adjusted according to different operational requirements.

[0069] In one example, the pressure-applying component 2 completely encloses the workpiece 1; in another example, the pressure-applying component 2 partially encloses the workpiece 1.

[0070] The number, size, position, and combination of pressure application components 2 are adjusted according to the actual situation. The purpose is to provide a uniform, stable, and controllable mechanical and thermal environment for workpiece 1 during the quenching process.

[0071] In one embodiment, when the end face area of ​​workpiece 1 is small or its shape is special, its axial solidification shrinkage is relatively small, reducing the need for axial compensating force; at the same time, its axial heat dissipation path is short, its self-cooling capacity is enhanced, and its dependence on additional cooling is also reduced. The pressure quenching device does not have an axial pressure applying component 22. In this case, the circumferential pressure F1 provided by the circumferential pressure applying component 21 can effectively suppress the shrinkage of the main body of the workpiece and can constrain axial deformation to a certain extent through friction.

[0072] In another implementation, the process still requires the application of axial pressure F2 to ensure dimensional accuracy. However, due to the small axial volume and low heat capacity of the workpiece, its heat can be effectively dissipated through the circumferential pressure application component 21 and the heat exchange component. Therefore, the critical heat exchange area of ​​the heat exchange component 3 is not integrated into the axial pressure application component 22. This simplifies the structure and reduces manufacturing costs while ensuring the pressure application function.

[0073] In one embodiment, the pressure applying component 2 is driven by an electric device to apply pressure. In one example, the pressure applying component 2 is driven by a hydraulic system controlled by a programmable logic controller (PLC); in another example, it is driven by a servo motor system controlled by a PLC.

[0074] In one embodiment, the pressure applying component 2 is directly pressured manually.

[0075] It should be understood that the magnitudes P of the circumferential pressure and the axial pressure are respectively 0 < P < 100 MPa. Since a relatively large pressure will damage the semi-solid metal workpiece or the organizational structure of the workpiece, and a relatively small pressure cannot achieve the effect of shrinkage prevention, in a preferred embodiment, a pressure of 0.1 - 30 MPa can prevent shrinkage of the semi-solid metal without deformation or crack generation.

[0076] It should be understood that the magnitudes of the circumferential pressure F1 and the axial pressure F2 are the same or different. In one embodiment, the circumferential pressure F1 and the axial pressure F2 are synchronous, and the magnitudes of the circumferential pressure F1 and the axial pressure F2 are the same. In one example, the magnitudes of the circumferential pressure F1 and the axial pressure F2 are the same, and a pressure of 0.2 MPa is applied to both.

[0077] In another embodiment, the magnitudes of the circumferential pressure F1 and the axial pressure F2 are different. The magnitude of the applied pressure increases with the increase in the thickness of the semi-solid metal workpiece, that is, the larger the circle of the longitudinal section of the semi-solid metal workpiece, the greater the applied pressure.

[0078] In one example, the temperature of the cooling medium is 10°C - 100°C. Applying at least one of the circumferential pressure F1 and the axial pressure F2 while cooling with a cooling medium of 10°C - 100°C can compensate for the volume shrinkage during the solidification of the liquid phase in the semi-solid metal rod, and can prevent cracks from occurring in the semi-solid metal rod during quenching. In another example, the temperature of the cooling medium is 20°C - 80°C.

[0079] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of changes or substitutions, which should all be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. A semi-solid metal pressure quenching device, characterized in that, include: The pressure application component is configured to apply circumferential pressure and / or axial pressure to a semi-solid metal workpiece; the magnitudes P of the circumferential pressure and axial pressure are respectively 0. <P<100MPa; A heat exchange component, integrated with the pressure application component, is used to cool the workpiece while the pressure application component applies pressure to the workpiece.

2. The semi-solid metal pressure quenching apparatus according to claim 1, characterized in that, The heat exchange component includes: A media circulation tank is used to store and regulate the cooling medium; A circulating pump, the inlet of which is connected to the medium circulation tank; A medium receiving cavity is disposed inside the pressure applying component; A medium inlet pipe connects the outlet of the circulating pump to the inlet of the medium receiving cavity; A media outlet pipe connects the outlet of the media receiving cavity to the media circulation tank.

3. The semi-solid metal pressure quenching apparatus according to claim 2, characterized in that, The medium-containing cavity is an integral cavity located inside the pressure-applying component.

4. The semi-solid metal pressure quenching apparatus according to claim 2, characterized in that, The medium-containing cavity is a distributed cooling channel.

5. The semi-solid metal pressure quenching apparatus according to any one of claims 2 to 4, characterized in that, Before the pressurization operation begins, the medium receiving cavity and the pipeline connected thereto are pre-filled with cooling medium.

6. The semi-solid metal pressure quenching apparatus according to claim 1, characterized in that, The heat exchange component includes a heat pipe, the working surface of which is flush with the pressure-applying surface of the pressure-applying component, so as to simultaneously contact the workpiece surface during pressure application.

7. The semi-solid metal pressure quenching apparatus according to claim 6, characterized in that, The pressure application component has a fixing groove, the heat pipe is embedded in the fixing groove, and the gap between the fixing groove and the heat pipe is filled with a filler, which includes thermally conductive grease, thermally conductive adhesive, solder or thermally conductive silicone.

8. The semi-solid metal pressure quenching apparatus according to claim 7, characterized in that, The heat pipe includes: The evaporation section is in direct contact with the workpiece and is embedded within the pressure application component; The condensation section extends outward from the side of the pressure-applying component; Alternatively, the pressure-applying component may have internal channels through which the condensation section extends outward.

9. The semi-solid metal pressure quenching apparatus according to claim 1, characterized in that, The shape of the pressure-applying surface of the pressure-applying component matches the surface of the workpiece.

10. The semi-solid metal pressure quenching apparatus according to claim 1, characterized in that, The pressure-applying component is configured to surround part or all of the surface of the workpiece.

11. The semi-solid metal pressure quenching apparatus according to claim 1, characterized in that, The pressure-applying component is driven by manual means or electric equipment to apply pressure.

12. A method for pressure quenching of semi-solid metal, using the pressure quenching apparatus according to any one of claims 1 to 11, characterized in that, Includes the following steps: Synchronous pressure cooling step: Apply at least one of circumferential pressure and axial pressure to the workpiece, and establish heat exchange with the surface of the workpiece through the heat exchange component at the moment of pressurization start-up, eliminating the time difference between cooling and pressurization.

13. The semi-solid metal pressure quenching method according to claim 12, characterized in that, The pressure applied to the workpiece is from 0.1 MPa to 30 MPa, and the cooling temperature is from 10°C to 100°C.

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