A tray for hot pressing and a hot pressing device

Abstract

The utility model relates to hot pressing sintering technical field especially relates to a tray for hot pressing and hot pressing device. The tray for hot pressing is located between upper hot pressing mould and lower hot pressing mould, and is used for carrying the target material to be pressed, and the tray includes upper circular platform part, transition part and lower circular platform part, through setting up upper circular platform part, transition part and lower circular platform part, when the bearing surface bears the downward pressure from upper hot pressing mould, the downward pressure of upper hot pressing mould is dispersed by upper circular platform part, thereby the stress intensity inside upper circular platform part is reduced, and the transition part transmits the dispersed downward pressure to lower circular platform part, avoids the phenomenon that the stress is concentrated in the edge of tray because of the inconsistent butt joint area of upper and lower surfaces of tray, and improves the stress generation situation inside tray. The hot pressing device provided by the utility model improves the stress generation situation inside tray by setting up the tray for hot pressing, and improves the structural rationality of hot pressing device.

Description

Technical Field

[0001] This utility model relates to the field of hot pressing sintering technology, and in particular to a hot pressing tray and hot pressing device. Background Technology

[0002] Tungsten alloy products are typically produced by hot-pressing sintering tungsten alloy targets. In this process, a tray carrying the tungsten alloy target is placed between a lower mold and an upper mold. The upper mold presses down and transfers heat from the heating element to the tungsten alloy target, thus gradually hot-pressing and sintering the target into the final tungsten alloy product.

[0003] Because the hot pressing sintering of tungsten alloy products is typically carried out under high temperature and high pressure, the upper and lower molds and pallets used must also withstand high temperatures and high pressures. However, ordinary cylindrical pallets will generate large shear stresses due to the uneven stress surfaces on the upper and lower surfaces, causing the pallets to crack and affecting their service life. Furthermore, pallet cracking can damage the heating elements in the hot pressing device, even leading to product scrapping, disrupting normal production, and increasing costs. The design challenge of the pallet lies in the uneven area of ​​its upper pressure surface and lower bearing surface, resulting in high internal stress and a tendency to crack.

[0004] Therefore, it is urgent to propose a solution to the above problems. Utility Model Content

[0005] The first objective of this invention is to provide a hot-pressing tray to solve the problem of high internal stress in existing trays, which can easily lead to cracking.

[0006] The second objective of this invention is to provide a hot pressing device to solve the problem of low reliability and durability of existing hot pressing devices.

[0007] Based on the above concept, the technical solution adopted by this utility model is as follows:

[0008] A hot pressing tray is located between an upper hot pressing mold and a lower hot pressing mold and is used to support a target material to be pressed. The upper hot pressing mold can press down and transfer heat to perform hot pressing sintering on the target material. The tray includes an upper frustum, a transition portion and a lower frustum. The transition portion connects the large end of the upper frustum and the large end of the lower frustum. The small end face of the upper frustum serves as a bearing surface to support the target material to be pressed, and the small end face of the lower frustum serves as a supporting surface to abut against the lower hot pressing mold.

[0009] Optionally, the area of ​​the bearing surface is smaller than the area of ​​the supporting surface.

[0010] Optionally, the transition portion is cylindrical, and the large end diameter of the upper frustum portion is the same as the large end diameter of the lower frustum portion, and they are respectively connected to the two ends of the transition portion.

[0011] Optionally, the upper frustum and the lower frustum have the same height.

[0012] Optionally, the diameter of the small end of the upper frustum is 0.4-0.8 times the diameter of the large end of the upper frustum, and the diameter of the small end of the lower frustum is 0.6-0.9 times the diameter of the large end of the lower frustum.

[0013] Optionally, the tray is made of graphite.

[0014] A hot pressing device includes a hot pressing tray, an upper hot pressing mold, a lower hot pressing mold, a driving mechanism, and a heating mechanism. The driving mechanism is connected to the upper hot pressing mold and can drive the upper hot pressing mold to press down. The heating mechanism is connected to both the upper and lower hot pressing molds and can transfer heat to the tray and the target material to be pressed through the upper and lower hot pressing molds.

[0015] Optionally, the hot pressing device further includes a housing component that can surround the target material to be pressed.

[0016] Optionally, the outer casing is made of carbon fiber.

[0017] Optionally, both the upper hot press mold and the lower hot press mold are made of graphite.

[0018] The beneficial effects of this utility model are:

[0019] This utility model proposes a hot pressing tray, located between an upper hot pressing mold and a lower hot pressing mold, for supporting the target material to be pressed. The upper hot pressing mold can press down and transfer heat to perform hot pressing sintering on the target material. The tray includes an upper truncated cone, a transition portion and a lower truncated cone. The transition portion connects the large end of the upper truncated cone and the large end of the lower truncated cone. The small end face of the upper truncated cone serves as a bearing surface to support the target material to be pressed, and the small end face of the lower truncated cone serves as a supporting surface to abut against the lower hot pressing mold. By incorporating an upper truncated cone, a transition section, and a lower truncated cone, the upper truncated cone's bearing surface bears the downward pressure from the upper hot press mold. Since the diameter of the upper truncated cone gradually increases from top to bottom, the downward pressure from the upper hot press mold is dispersed by the upper truncated cone and transmitted to the transition section, thus reducing the stress intensity inside the upper truncated cone. The transition section then transmits the dispersed downward pressure to the lower truncated cone. Because the diameter of the lower truncated cone gradually decreases from top to bottom, the downward pressure generated by the upper hot press mold gradually converges on the supporting surface of the lower truncated cone and is transmitted to the lower hot press mold, rather than being directly transmitted vertically to it. This avoids the phenomenon of stress concentration at the pallet edge caused by inconsistent contact areas between the upper and lower surfaces of the pallet, thereby improving the stress generation situation inside the pallet and extending its service life.

[0020] The hot pressing device proposed in this utility model avoids the phenomenon of stress concentration at the edge of the tray due to the inconsistent contact area between the upper and lower surfaces of the tray by setting a hot pressing tray, thereby improving the stress generation inside the tray and enhancing the reliability of the hot pressing device. The driving mechanism of the hot pressing device can drive the upper hot pressing mold to press down, improving the degree of automation and thus improving the hot pressing sintering efficiency. The heating mechanism can generate high temperature and transfer it to the tray and the target material to be pressed through the upper and lower hot pressing molds, improving the structural rationality of the hot pressing device. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments of this utility model will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the content of the embodiments of this utility model and these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the structure of the hot pressing device provided in this embodiment of the utility model;

[0023] Figure 2 This is a schematic diagram of the structure of the hot-pressing tray provided in this embodiment of the utility model;

[0024] Figure 3 This is a diagram showing experimental data on the load-bearing capacity of a pallet in the prior art, provided by an embodiment of this utility model.

[0025] Figure 4 This is a graph showing the load-bearing capacity test data of the hot-pressing tray provided in this embodiment of the utility model.

[0026] In the picture:

[0027] 100. Target material to be pressed;

[0028] 1. Pallet; 11. Upper frustum; 12. Transition section; 13. Lower frustum; 2. Upper hot press mold; 3. Lower hot press mold; 4. Outer shell. Detailed Implementation

[0029] To make the technical problem solved by this utility model, the technical solution adopted, and the technical effect achieved clearer, the technical solution of this utility model will be further described below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely for explaining this utility model and not for limiting it. Furthermore, it should be noted that, for ease of description, only the parts related to this utility model are shown in the accompanying drawings, not all of them.

[0030] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0031] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0032] In this utility model, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature. In the description of this embodiment, unless otherwise specified, "multiple" specifically refers to two or more.

[0033] In the description of this embodiment, the terms "upper," "lower," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, 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 utility model. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0034] It should be noted that when a component is referred to as "fixed to" or "set on" another component, it can be directly on the other component or it can be located in between the component.

[0035] The technical solution of this utility model will be further described below with reference to the accompanying drawings and specific embodiments.

[0036] This embodiment proposes a hot-pressing tray and a hot-pressing device to solve the problem in the prior art where the internal stress of the tray is too large, which easily leads to cracking.

[0037] In existing technologies, tungsten alloy products are typically produced by hot-pressing sintering tungsten alloy targets. Hot-pressing sintering refers to a process in which powder materials are rapidly densified under the combined action of high temperature and high pressure, through uniform heat transfer and stress dispersion using a mold.

[0038] In the hot pressing sintering process, a tray carrying a tungsten alloy target is often placed between a lower mold and an upper mold. The upper mold presses down and transfers heat from the heating element to the tungsten alloy target, gradually hot pressing and sintering the target into a tungsten alloy product. Ordinary cylindrical trays, when subjected to the downward pressure of the upper mold, experience significant shear stress due to the uneven force distribution between the upper and lower surfaces. This can cause the tray to crack, affecting its lifespan. Furthermore, tray cracking can damage the heating element in the hot pressing device, even leading to product scrap, disrupting normal production, and increasing costs.

[0039] To solve this problem, such as Figures 1-2 As shown, in this embodiment, the hot pressing tray 1 is located between the upper hot pressing mold 2 and the lower hot pressing mold 3, and is used to support the target material 100 to be pressed. The upper hot pressing mold 2 can press down and transfer heat to perform hot pressing sintering on the target material 100. The tray 1 includes an upper frustum 11, a transition portion 12 and a lower frustum 13. The transition portion 12 is connected between the large end of the upper frustum 11 and the large end of the lower frustum 13. The small end face of the upper frustum 11 is the bearing surface to support the target material 100 to be pressed, and the small end face of the lower frustum 13 is the supporting surface to abut against the lower hot pressing mold 3.

[0040] Understandably, by providing an upper frustum 11, a transition portion 12, and a lower frustum 13, when the bearing surface of the upper frustum 11 bears the downward pressure from the upper hot press mold 2, since the diameter of the upper frustum 11 gradually increases from top to bottom, the downward pressure from the upper hot press mold 2 is dispersed by the upper frustum 11 and transmitted to the transition portion 12, thereby reducing the stress intensity inside the upper frustum 11. The transition portion 12 then transmits the dispersed downward pressure to the lower frustum 13. Since the diameter of the lower frustum 13 gradually decreases from top to bottom, the downward pressure generated by the upper hot press mold 2 will gradually converge on the supporting surface of the lower frustum 13 and be transmitted to the lower hot press mold 3, rather than being directly transmitted vertically to the lower hot press mold 3. Even if the contact area between the upper and lower surfaces of the tray 1 is inconsistent, it is difficult to generate a large amount of stress, thereby avoiding the phenomenon of stress concentration at the edge of the tray 1 caused by the inconsistent contact area between the upper and lower surfaces of the tray 1. This improves the stress generation situation inside the tray 1 and extends the service life of the tray 1.

[0041] like Figure 3 As shown, under certain conditions, the maximum bearing pressure of a cylindrical tray in the prior art is 5.52MPa-355MPa.

[0042] like Figure 4 As shown in the experiment, under the same target material, target size, sintering conditions, and downward pressure as the cylindrical tray in the prior art, the maximum bearing pressure of the hot pressing tray 1 proposed in this embodiment is 1.2MPa-319.14MPa. The maximum bearing pressure of the hot pressing tray 1 proposed in this embodiment is 35.86MPa less than that of the cylindrical tray in the prior art, which inevitably effectively reduces the internal stress intensity.

[0043] Optionally, the area of ​​the bearing surface is smaller than the area of ​​the supporting surface. This arrangement makes the divergence effect of the downward pressure generated by the upper frustum 11 on the upper hot press mold 2 better than the convergence effect of the lower frustum 13 on the downward pressure, thereby giving the lower frustum 13 a more stable supporting capacity and preventing cracking of the lower frustum 13 due to excessive convergence. This further reduces the generation of internal stress in the pallet 1 and extends the service reliability of the pallet 1.

[0044] Optionally, the transition portion 12 is cylindrical, with the large end diameter of the upper frustum portion 11 being the same as the large end diameter of the lower frustum portion 13, and both ends of the transition portion 12 being connected respectively. This arrangement allows the transition portion 12 to evenly transmit the force of the upper frustum portion 11 to the lower frustum portion 13, thereby preventing itself from cracking and extending the service life of the tray 1.

[0045] Optionally, the upper frustum 11 and the lower frustum 13 have the same height. This arrangement ensures better consistency between the upper frustum 11 and the lower frustum 13, thereby reducing the manufacturing difficulty of both and improving user satisfaction.

[0046] Optionally, the diameter of the smaller end of the upper frustum 11 is 0.4-0.8 times the diameter of the larger end of the upper frustum 11, and the diameter of the smaller end of the lower frustum 13 is 0.6-0.9 times the diameter of the larger end of the lower frustum 13. This arrangement makes the divergence effect of the downward pressure generated by the upper frustum 11 on the upper hot press mold 2 better than the convergence effect of the lower frustum 13 on the downward pressure, giving the lower frustum 13 a more stable supporting capacity. Furthermore, this ratio results in higher structural strength of the pallet 1, further improving the reliability of the pallet 1 in use.

[0047] Of course, in other embodiments, the ratio of the small end diameter of the upper frustum 11 to the large end diameter of the upper frustum 11, and the ratio of the small end diameter of the lower frustum 13 to the large end diameter of the lower frustum 13 are not limited to these. They can be selected as needed according to the actual application scenario, and no further restrictions are imposed here.

[0048] Optionally, tray 1 is made of graphite. Graphite components have the ability to withstand high pressure and high temperature, and have good thermal conductivity, which is conducive to the realization of hot pressing sintering process and improves user satisfaction.

[0049] Of course, in other embodiments, the tray 1 can also be made of other components, which can be selected as needed according to the type of the target material 100 to be pressed and the application scenario, without too many restrictions.

[0050] The hot pressing device proposed in this embodiment includes a hot pressing tray 1. The hot pressing device also includes an upper hot pressing mold 2, a lower hot pressing mold 3, a driving mechanism, and a heating mechanism. The driving mechanism is connected to the upper hot pressing mold 2 and can drive the upper hot pressing mold 2 to press down. The heating mechanism is connected to both the upper hot pressing mold 2 and the lower hot pressing mold 3 and can transfer heat to the tray 1 and the target material 100 to be pressed through the upper hot pressing mold 2 and the lower hot pressing mold 3.

[0051] Understandably, by setting up a hot pressing tray 1, the downward pressure of the upper hot pressing mold 2 is dispersed by the upper frustum 11 and transmitted to the transition section 12, thereby reducing the stress intensity inside the upper frustum 11. The transition section 12 then transmits the dispersed downward pressure to the lower frustum 13. The downward pressure generated by the upper hot pressing mold 2 will gradually converge on the support surface of the lower frustum 13 and be transmitted to the lower hot pressing mold 3. This avoids the phenomenon of stress concentration at the edge of the tray 1 due to the inconsistent contact area between the upper and lower surfaces of the tray 1, thereby improving the stress generation situation inside the tray 1 and enhancing the reliability of the hot pressing device.

[0052] Furthermore, the drive mechanism of the hot pressing device can drive the upper hot pressing mold 2 to press down, improving the degree of automation and thus improving the hot pressing sintering efficiency. The heating mechanism can generate high temperature and transfer it to the tray 1 and the target material 100 to be pressed through the upper hot pressing mold 2 and the lower hot pressing mold 3, improving the structural rationality of the hot pressing device.

[0053] For example, the drive mechanism includes a hydraulic cylinder, the movable end of which drives the upper hot press mold 2 to press down. This configuration improves the pressing strength and efficiency of the upper hot press mold 2, thereby enhancing the reliability of the hot pressing device.

[0054] Of course, in other embodiments, other driving sources such as cylinders or electric cylinders can also be used to drive the upper hot press mold 2. The choice can be made as needed according to the actual application scenario, and no further restrictions are imposed here.

[0055] For example, the heating mechanism includes a heating wire connected to the upper hot pressing mold 2 and the lower hot pressing mold 3. This arrangement uses the heating wire to generate high temperatures on the upper hot pressing mold 2 and the lower hot pressing mold 3, thereby transferring the high temperature to the target material 100 to be pressed and the tray 1, to help realize the hot pressing sintering process and improve the structural rationality of the hot pressing device.

[0056] Of course, other heating elements may be used in other embodiments, and no further restrictions are imposed here.

[0057] Optionally, the hot pressing apparatus also includes a housing 4, which can surround the periphery of the target material 100 to be pressed. This arrangement uses the housing 4 to position the target material 100 to be pressed, thereby accelerating the hot pressing sintering to form the product and improving the user experience of the hot pressing apparatus.

[0058] For example, the outer casing 4 is made of carbon fiber. The carbon fiber casing has high strength and rigidity, and is corrosion-resistant, thereby improving the reliability of the hot pressing device. Of course, in other embodiments, other types of casings can be used, selected as needed according to the application scenario; no further restrictions are imposed here.

[0059] Optionally, both the upper hot press mold 2 and the lower hot press mold 3 are made of graphite. This configuration improves the high temperature and high pressure resistance, as well as the thermal conductivity of the upper hot press mold 2 and the lower hot press mold 3, thereby enhancing the reliability of the hot press device.

[0060] The working process of the hot pressing device proposed in this embodiment is as follows:

[0061] First, place the target material 100 to be pressed on top of the tray 1, and set the tray 1 on the upper side of the lower hot press mold 3, and set the outer shell 4 around the target material 100 to be pressed.

[0062] Then, the drive mechanism and heating mechanism are activated to heat up the upper hot pressing mold 2 and the lower hot pressing mold 3, and to make the upper hot pressing mold 2 press against the target material 100 to be pressed and gradually move down until the hot pressing sintering process is completed.

[0063] Finally, drive the hot press mold 2 to move upward, remove the outer shell 4, take out the hot-pressed product, and observe whether the tray 1 has cracks. If there are cracks, the tray 1 needs to be replaced. Then turn off the drive mechanism and the heating mechanism.

[0064] Note that the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of the present invention. The scope of the present invention is determined by the scope of the appended claims.

Claims

1. A hot pressing tray, located between an upper hot pressing mold (2) and a lower hot pressing mold (3), for supporting a target material (100) to be pressed, wherein the upper hot pressing mold (2) is capable of pressing down and transferring heat to perform hot pressing sintering on the target material (100), characterized in that, The tray includes an upper frustum (11), a transition portion (12), and a lower frustum (13). The transition portion (12) is connected between the large end of the upper frustum (11) and the large end of the lower frustum (13). The small end face of the upper frustum (11) is a bearing surface to bear the target material (100) to be pressed, and the small end face of the lower frustum (13) is a supporting surface to abut against the lower hot press mold (3).

2. The pallet according to claim 1, characterized in that, The area of ​​the bearing surface is smaller than the area of ​​the supporting surface.

3. The tray according to claim 1, characterized in that, The transition portion (12) is cylindrical, and the large end diameter of the upper frustum portion (11) is the same as the large end diameter of the lower frustum portion (13), and they are respectively connected to the two ends of the transition portion (12).

4. The tray according to claim 1, characterized in that, The upper frustum (11) and the lower frustum (13) have the same height.

5. The pallet according to claim 1, characterized in that, The diameter of the small end of the upper frustum (11) is 0.4-0.8 times the diameter of the large end of the upper frustum (11), and the diameter of the small end of the lower frustum (13) is 0.6-0.9 times the diameter of the large end of the lower frustum (13).

6. The pallet according to claim 1, characterized in that, The tray is made of graphite.

7. A hot pressing device, characterized in that, The hot pressing device includes a hot pressing tray as described in any one of claims 1-6. The hot pressing device also includes an upper hot pressing mold (2), a lower hot pressing mold (3), a driving mechanism, and a heating mechanism. The driving mechanism is connected to the upper hot pressing mold (2) and can drive the upper hot pressing mold (2) to press down. The heating mechanism is connected to both the upper hot pressing mold (2) and the lower hot pressing mold (3) and can transfer heat to the tray and the target material (100) to be pressed through the upper hot pressing mold (2) and the lower hot pressing mold (3).

8. The hot pressing device according to claim 7, characterized in that, The hot pressing device also includes a housing (4) which can surround the target material (100) to be pressed.

9. The hot pressing device according to claim 8, characterized in that, The outer casing (4) is made of carbon fiber.

10. The hot pressing device according to claim 7, characterized in that, Both the upper hot press mold (2) and the lower hot press mold (3) are made of graphite.

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