A method and apparatus for injection molding porous ceramic sandwich

Abstract

The present application relates to a kind of porous ceramic sandwich injection molding method, and it relates to injection molding technical field.A kind of porous ceramic sandwich injection molding method, comprising the following steps: first feeding and second feeding are injection molded into mold cavity, the start time of second feeding injection molding is later than the start time of first feeding injection molding, and after cooling demolding, obtain porous ceramic green body;The first feeding includes, quartz glass 35-50wt%, complex phase additive 5-10wt%, pore-forming agent 20-40wt%, sintering aid 5-15wt%, binder 5-15wt%;Second feeding includes, quartz glass 55-70wt%, complex phase additive 4-8wt%, pore-forming agent 5-15wt%, sintering aid 5-15wt%, binder 5-15wt%.The porous ceramic with different inner and outer layer structure is obtained by sandwich injection molding method in the present application, the relationship between the anti-leakage and the taste of consumer use is balanced, has good anti-leakage, improves the taste of consumer use when it is used as ceramic atomization core, improves the use of consumer experience.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of injection molding, in particular to a porous ceramic sandwich injection molding method and device. BACKGROUND

[0002] The existing atomization core is generally divided into two categories of cotton core and ceramic core. The ceramic atomization core generally includes a ceramic base body and a heating circuit. The heating circuit currently includes resistance wires, etched mesh sheets and thick film printed circuits and various forms. The heating circuits of these forms are solid heating bodies, and when atomizing, the heating circuit generates heat and transfers it to the ceramic, and then forms a thermal gradient around the solid heating body, and the ceramic body heats and vaporizes the atomized liquid to form an atomized aerosol.

[0003] The leakage risk and taste of the ceramic atomization core are directly related to the porosity and pore size distribution of the porous ceramic as the base body. When the porosity of the ceramic base body is low and the pore size is small, the leakage prevention is good, but the taste is poor; when the porosity of the ceramic core is high and the pore size is large, the taste is better, but the leakage risk is also increased. That is, the ceramic base body with a single pore layer structure is difficult to balance the relationship between leakage prevention and consumer taste, thereby leading to poor performance of the ceramic atomization core or reduced consumer acceptance.

[0004] Therefore, in order to balance the relationship between leakage prevention and consumer taste of the ceramic base body, a porous ceramic with different inner and outer layer structures is needed to be researched, the inner layer has low porosity and small pore size, which can prevent the atomized liquid from leaking to reduce the use rate of the atomized liquid and increase the cost; the outer layer has high porosity and large pore size, which facilitates the permeation of the atomized liquid after atomization, increases the permeation amount of the atomized liquid after atomization, and thereby improves the taste of the consumer during use and improves the consumer's use experience. SUMMARY

[0005] The present application aims to solve the above problems and provide a porous ceramic sandwich injection molding method, which obtains a porous ceramic with different inner and outer layer structures through the sandwich injection molding method, balances the relationship between leakage prevention and consumer taste, has good leakage prevention, and improves the consumer's use taste when applied as a ceramic atomization core, thereby improving the consumer's use experience.

[0006] Meanwhile, the present application also provides a porous ceramic sandwich injection molding device, which is matched with the porous ceramic sandwich injection molding method, can realize the purpose of sandwich injection, and makes the inner and outer layer structures of the injection molded porous ceramic closely combined, and improves the overall performance such as mechanical properties and thermal properties of the prepared porous ceramic and the yield rate.

[0007] Specifically:

[0008] The application discloses a porous ceramic sandwich injection molding method, comprising the following steps:

[0009] The first feeding and the second feeding are injected into a mold cavity, and the second feeding is injected later than the first feeding, and then the porous ceramic green body is obtained after cooling and demolding;

[0010] The first feeding comprises 35-50wt% of quartz glass, 5-10wt% of complex phase additives, 20-40wt% of pore-forming agents, 5-15wt% of sintering aids and 5-15wt% of binders;

[0011] The second feeding comprises 55-70wt% of quartz glass, 4-8wt% of complex phase additives, 5-15wt% of pore-forming agents, 5-15wt% of sintering aids and 5-15wt% of binders.

[0012] Preferably, the mesh number of the quartz glass is 250-350 mesh.

[0013] Preferably, the complex phase additives are a mixture of at least two of titanium oxide, yttrium oxide and zirconium oxide; the mass ratio of the titanium oxide and the yttrium oxide is 1:1.1-1.5, and / or the mass ratio of the titanium oxide and the zirconium oxide is 1:1.1-1.5, and / or the mass ratio of the yttrium oxide and the zirconium oxide is 1:1.1-1.5.

[0014] Preferably, the pore-forming agents can be selected from a mixture of one or more of polyoxymethylene, polymethyl methacrylate and polystyrene.

[0015] Preferably, the binders can be selected from a mixture of one or more of paraffin, ethylene-vinyl acetate copolymer and stearic acid.

[0016] Preferably, the sintering aids can be selected from a mixture of one or more of glass powder, boron trioxide and barium carbonate.

[0017] Preferably, when the first feeding is injected, the plasticizing temperature is 70-90 DEG C, the rotating speed is 30-60 rpm and the injection speed is 30-50 mm / s; when the second feeding is injected, the plasticizing temperature is 70-90 DEG C, the rotating speed is 30-50 rpm and the injection speed is 10-30 mm / s.

[0018] The application further discloses a porous ceramic sandwich injection molding device used in the porous ceramic sandwich injection molding method, which is used for injecting the first feeding material and the second feeding material into a mold cavity.

[0019] Preferably, a base body is arranged in the cavity of the rear mold cavity.

[0020] The application further discloses a porous ceramic obtained by debinding and sintering a porous ceramic green body.

[0021] In the debinding and sintering, the sintering is performed at a temperature rising rate of 200-230 DEG C / h to 880-920 DEG C, and then kept for 2-4 h, and then the temperature is raised to 1000-1200 DEG C at a temperature rising rate of 90-120 DEG C / h, and then kept for 2-4 h.

[0022] Advantages:

[0023] (1) The porous ceramic sandwich injection molding method can stack and injection mold two different feeding materials, and the second feeding material is stacked on the uncured first feeding material, so that the different feeding materials are fused together during injection molding, and can jointly experience curing and debinding and sintering, so that the different feeding materials are tightly combined and closely connected in structure, the yield of the ceramic green body is improved, and the strength of the porous ceramic obtained by sintering is improved.

[0024] (2) The porous ceramic sandwich injection molding device can be combined with the porous ceramic sandwich injection molding method, that is, the first injection machine cylinder and the second injection machine cylinder can timely adjust the time of adding different feeding materials according to the properties of different feeding materials, so as to prepare ceramic green bodies with different performance requirements, and obtain the required porous ceramic by sintering, and the feeding material can be conveniently supplemented, that is, the porous ceramic sandwich injection molding method is convenient and fast, and can prepare ceramic green bodies with different inner and outer layer structures according to the adjustment of different feeding materials and injection molding parameters, and then obtain porous ceramics with different inner and outer layer structures by sintering, so that the application range is wide and the yield is high.

[0025] (2) The porous ceramic green body prepared by the porous ceramic sandwich injection molding method of the present application can be sintered to obtain a porous ceramic with different inner and outer layer structures, the inner layer of which has a lower porosity and smaller pore size, and the outer layer of which has a higher porosity and larger pore size, and can be used in a ceramic atomization core, and when used as a ceramic matrix of the ceramic atomization core, can balance the relationship between the leakproofness and the taste of the consumer, prevent the leakage of atomized liquid, prolong the service life of the atomization core, reduce the use cost, enhance the atomization amount, enhance the taste, and improve the evaluation of the consumer. BRIEF DESCRIPTION OF DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0027] Figure 1 It is a schematic diagram of the flow channel device in the porous ceramic sandwich injection molding device of the present application.

[0028] Figure 2 It is a schematic diagram of the first flow channel device in the porous ceramic sandwich injection molding device of the present application.

[0029] Figure 3 It is a schematic diagram of the porous ceramic sandwich injection molding device of the present application.

[0030] Figure 4 It is a sectional view along F-F of the porous ceramic sandwich injection molding device of the present application.

[0031] Figure 5 It is an enlarged schematic diagram of point G of the porous ceramic sandwich injection molding device of the present application.

[0032] Figure 6 It is a top view of the porous ceramic sandwich injection molding device of the present application.

[0033] Figure 7 It is a sectional view along B-B of the porous ceramic sandwich injection molding device of the present application.

[0034] Figure 8 It is an enlarged schematic diagram of point H of the porous ceramic sandwich injection molding device of the present application.

[0035] Figure 9 It is a schematic diagram of the front mold fixed plate of the porous ceramic sandwich injection molding device of the present application.

[0036] Figure 10 It is a schematic diagram of the rear mold fixed plate of the porous ceramic sandwich injection molding device of the present application.

[0037] Identified in the figure:

[0038] 1 - first runner device; 101 - first main runner; 102 - first sub-runner; 103 - first cold sprue; 104 - base exterior; 105 - first injection machine barrel; 601 - first gate;

[0039] 2 - second runner device; 201 - second main runner; 202 - second sub-runner; 203 - second cold sprue; 204 - base interior; 205 - second injection machine barrel; 602 - second gate;

[0040] 502 - injection machine back platen; 403 - back mold fixing plate; 401 - back mold frame; 402 - back mold cavity; 302 - front mold core; 301 - front mold frame; 501 - injection machine front platen. DETAILED DESCRIPTION

[0041] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are some of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the present application.

[0042] It should be understood that, when used in the specification and the appended claims, the terms "comprise" and "include" indicate the presence of the described features, integers, steps, operations, elements, and / or components, but do not exclude one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0043] It should also be understood that the terms used in the specification of the present application are only for the purpose of describing the specific embodiments and are not intended to limit the present application. As used in the specification and the appended claims of the present application, the singular forms "a", "an" and "the" are intended to include the plural forms, unless the context clearly indicates otherwise.

[0044] It should be further understood that the term "and / or" used in the specification and the appended claims of the present application means any combination of one or more of the associated listed items and all possible combinations, and includes these combinations.

[0045] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the present application is usually placed during use, and are merely for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0046] The terms "first", "second", and the like are merely used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0047] The terms "horizontal", "vertical", "suspended" and the like do not mean that the components must be absolutely horizontal, vertical or suspended, but can be slightly inclined. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined.

[0048] In the description of the present application, it should be noted that, unless otherwise explicitly specified and limited, the terms "arrangement", "installation", "connection", "connection" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be directly connected, or indirectly connected through an intermediate medium, or it can be connected inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0049] A porous ceramic sandwich injection molding device

[0050] As Figures 1-8 , including injection molding machine cylinder, flow channel device; the injection molding machine cylinder is pressed out through the flow channel device. The injection molding machine cylinder comprises a first injection molding machine cylinder 105 and a second injection molding machine cylinder 205; the flow channel device comprises a first flow channel device 1 and a second flow channel device 2; the first injection molding machine cylinder 105 is connected with the first flow channel device 1, specifically, the discharge port of the first injection molding machine cylinder 105 is connected with the feeding port of the first flow channel device 1; the first injection molding machine cylinder 105 can press the feed into the first flow channel device 1 and be pressed out through the first flow channel device 1. The second injection molding machine cylinder 205 is connected with the second flow channel device 2, specifically, the discharge port of the second injection molding machine cylinder 205 is connected with the feeding port of the second flow channel device 2; the second injection molding machine cylinder 205 can press the feed into the second flow channel device 2 and be pressed out through the second flow channel device 2. The injection molding machine cylinder is used for loading, and the loaded feed is pressed into the flow channel device, and then is pressed out through the flow channel device.

[0051] The feeding port of the flow channel device is connected with the cylinder of the injection molding machine at one end and the nozzle at the other end, that is, the feeding material can be pressed into the flow channel device from the cylinder of the injection molding machine and pressed out from the nozzle. Specifically, the feeding port of the first flow channel device 1 is connected with the first cylinder 105 of the injection molding machine at one end and the first nozzle 601 at the other end; the feeding port of the second flow channel device 2 is connected with the second cylinder 205 of the injection molding machine at one end and the second nozzle 602 at the other end.

[0052] The flow channel device further comprises a main flow channel and a branch flow channel; the feeding port of the flow channel device is communicated with the main flow channel, and then communicated with the nozzle through the branch flow channel; specifically, the feeding port of the first flow channel device 1 is communicated with the first main flow channel 101, and then communicated with the first nozzle 601 through the first branch flow channel 102; the feeding port of the second flow channel device 2 is communicated with the second main flow channel 201, and then communicated with the first nozzle 602 through the second branch flow channel 202.

[0053] The branch flow channel and the main flow channel have an included angle, preferably, the included angle can be 90°, that is, the branch flow channel is preferably perpendicular to the main flow channel and communicated. Moreover, the connection part of the branch flow channel and the main flow channel is further provided with a cold material handle for shunting the excess feeding material; specifically, the connection part of the first branch flow channel 102 and the first main flow channel 101 is further provided with a first cold material handle 103, the first cold material handle 103 is communicated with the connection part of the first branch flow channel 102 and the first main flow channel 101, and when the feeding material in the first flow channel device 1 is too much, the excess feeding material can be shunted; at the same time, the connection part of the second branch flow channel 202 and the second main flow channel 201 is further provided with a second cold material handle 203, the second cold material handle 203 is communicated with the connection part of the second branch flow channel 202 and the second main flow channel 201, and when the feeding material in the second flow channel device 2 is too much, the excess feeding material can be shunted.

[0054] As Figure 10 The porous ceramic sandwich injection molding device further comprises a rear mold cavity 402, the rear mold cavity 402 is provided with holes corresponding to the first branch flow channel 102, the first nozzle 601, the second branch flow channel 202 and the second nozzle 602, and the part connected with the holes corresponding to the first nozzle 601 and the second nozzle 602 is further provided with a cavity, which can be designed according to the shape of the ceramic matrix to be prepared, which is the matrix exterior 104; that is, the cavity of the rear mold cavity 402 is provided with the matrix exterior 104. The matrix interior 204 region is further provided in the matrix exterior 104, that is, the matrix interior 204 is wrapped in the matrix exterior 104, and no barrier is provided between the two.

[0055] The first nozzle 601 is connected with the matrix exterior 104, specifically, the first injection molding machine cylinder 105 can press the feeding material into the matrix exterior 104 through the first nozzle 601. The second nozzle 602 is connected with the matrix interior 204, specifically, the second injection molding machine cylinder 205 can press the feeding material into the matrix interior 204 through the second nozzle 602.

[0056] It should be noted that the connection between the base exterior 104 and the first gate 601 and the connection between the base interior 204 and the second gate 602 can be at the same place, and the first gate 601 and the second gate 602 are separated to prevent the feed from being blended in advance during injection molding.

[0057] Specifically, the first injection molding machine barrel 105 injects the feed into the base exterior 104 through the first gate 601, and the second injection molding machine barrel 205 injects the feed into the base interior 204 area through the second gate 602, and after curing, a porous ceramic with different internal and external structures is obtained, that is, a porous ceramic with different internal and external structures; wherein the internal and external parts of the base are sintered together and combined more tightly, and at the same time have different structures, which can meet different performance requirements.

[0058] The first runner 102, the first gate 601, the second runner 202, and the second gate 602 can be nested in the rear mold cavity 402 through the hole. Specifically, the first cold material handle 103 can pass through the hole, and then the first runner 102, the first gate 601, and the rear mold cavity 402 are nested, and at the same time, the second cold material handle 203 can pass through the hole, and then the second runner 202, the second gate 602, and the rear mold cavity 402 are nested.

[0059] The rear mold cavity 402 is arranged on the rear mold frame 401, and the rear mold frame 401 is fixedly arranged on the rear mold fixed plate 403. Therefore, the first cold material handle 103, the first runner 102, and the first gate 601 pass through the hole arranged on the rear mold cavity 402 and are nested with the rear mold cavity 402, and are fixed on the rear mold frame 401 of the rear mold fixed plate 403; at the same time, the second cold material handle 203, the second runner 202, and the second gate 602 pass through the hole arranged on the rear mold cavity 402 and are nested with the rear mold cavity 402, and are fixed on the rear mold frame 401 of the rear mold fixed plate 403.

[0060] As Figure 9 , the front mold core 302 is provided with a hole corresponding to the first main runner 101 and the second main runner 201; the first main runner 101 connected with the first gate 601 through the first runner 102 and the second main runner 201 connected with the second gate 602 through the second runner 202 can pass through the hole of the front mold core 302 and be nested with the front mold core 302.

[0061] The front mold core 302 is arranged on the front mold frame 301, and the front mold frame 301 is fixedly arranged on the front mold fixed plate 303. Specifically, the front mold frame 301 and the front mold fixed plate 303 are arranged with corresponding holes, the first main flow channel 101 passes through the hole arranged on the front mold core 302 and simultaneously penetrates the front mold frame 301 and the front mold fixed plate 303, so as to be fixedly connected with the front mold fixed plate 303; at the same time, the second main flow channel 201 passes through the hole arranged on the front mold core 302 and simultaneously penetrates the front mold frame 301 and the front mold fixed plate 303, so as to be fixedly connected with the front mold fixed plate 303.

[0062] In order to ensure that the injection molding machine is tightly connected with the base body and prevent material leakage during the injection molding process, the porous ceramic sandwich injection molding device is further provided with an injection molding machine front plate 501 and an injection molding machine rear plate 502; the injection molding machine front plate 501 is arranged between the first injection molding machine barrel 105, the second injection molding machine barrel 205 and the front mold fixed plate 303, and the injection molding machine front plate 501 is provided with a through hole corresponding to the positions of the first main flow channel 101 and the second main flow channel 201, so as to facilitate the connection of the first injection molding machine barrel 105 with the first main flow channel 101 through the through hole and the pressing of the feeding material into the first main flow channel 101, and facilitate the connection of the second injection molding machine barrel 205 with the second main flow channel 201 through the through hole and the pressing of the feeding material into the second main flow channel 201.

[0063] The injection molding machine rear plate 502 is arranged below the rear mold fixed plate 403, and when the injection molding machine front plate 501 is pressed and combined in correspondence, the rear mold fixed plate 403 and the front mold fixed plate 303 placed in the middle are tightly combined, so that the base body interior 204 and the base body exterior 104 are wrapped between the rear mold cavity 402 and the front mold core 302 and are in a sealed state. When the base body exterior 104 contains the feeding material, the base body interior 204 region wrapped therein can be connected with the second injection molding machine barrel 205 through the second gate 602, the second flow channel 202 and the second main flow channel 201, and the feeding material can be pressed into the base body interior 204 by the second injection molding machine barrel 205.

[0064] The flow channel device is fixedly connected at one end with the rear mold cavity 402 and at the other end penetrates the front mold core 302 and is connected with the injection molding machine barrel; specifically, the first flow channel device 1 is fixedly connected at one end with the rear mold cavity 402 and at the other end penetrates the front mold core 302 and is connected with the first injection molding machine barrel 105; the second flow channel device 2 is fixedly connected at one end with the rear mold cavity 402 and at the other end penetrates the front mold core 302 and is connected with the second injection molding machine barrel 205.

[0065] Then the base exterior 104 is arranged on the back cavity 402, the back fixed plate 403 and the front fixed plate 303 are tightly adhered by the front machine plate 501 and the back machine plate 502 of the injection molding machine, specifically, the back fixed plate 403 connected with the back cavity 402 and the front fixed plate 303 connected with the front core 302 are pressed to make the front core 302 and the back cavity 402 tightly press, forming a closed space of the base exterior 104 in the back cavity 402, and then the feeding is pressed into the base exterior 104 to form the exterior of the ceramic base, at this time, the feeding is pressed into the base interior 204 area on the base exterior 104 where the feeding is pressed before, forming the interior of the ceramic base.

[0066] A porous ceramic sandwich injection molding device can be used for sandwich injection molding to prepare a porous ceramic with double feedings.

[0067] Before preparation, the porous ceramic sandwich injection molding device needs to be assembled, specifically as follows:

[0068] The front core 302 is fixedly connected with the front mold frame 301 fixedly arranged on the front fixed plate 303, and the back cavity 402 is fixedly connected with the back mold frame 401 fixedly arranged on the back fixed plate 403; then, the first cold handle 103 of the first flow channel device 1 is pushed into the hole on the back cavity 402 to make the first branch flow channel 102 and the first gate 601 nested with the hole on the back cavity 402, and the second cold handle 203 of the second flow channel device 2 is pushed into the hole on the back cavity 402 to make the second branch flow channel 202 and the second gate 602 nested with the hole on the back cavity 402.

[0069] Then, the first main flow channel 101 and the second main flow channel 201 are nested with the corresponding holes on the front core 301, the first main flow channel 101 and the second main flow channel 201 are stretched out through the holes on the front core 301 and the front fixed plate 303, and then they are penetrated through the corresponding through holes on the front machine plate 501 of the injection molding machine.

[0070] At this time, the back fixed plate 403 is pressed to the front fixed plate 303 by the back machine plate 502 of the injection molding machine, and the base exterior 104 and the base interior 204 in the back cavity 402 form a dense cavity; then, the discharge port of the first injection molding machine cylinder 105 is connected with the feeding port of the first flow channel device 1, and then connected with the first main flow channel 101, and the discharge port of the second injection molding machine cylinder 205 is connected with the feeding port of the second flow channel device 2, and then connected with the second main flow channel 201, that is, the assembly of the device is completed.

[0071] After that, only need to fill the first injection molding machine cylinder 105, the second injection molding machine cylinder 205 into the feeding, and then through the first injection molding machine cylinder 105, the feeding is pressed into the base outside 104, after the feeding is pressed into the base outside 104, the feeding is pressed into the base inside 204 on the base outside 104 through the second injection molding machine cylinder 205, and the injection molding porous ceramic green body is obtained, and after sintering, the porous ceramic is obtained.

[0072] A porous ceramic sandwich injection molding method, comprising the following steps:

[0073] The first feeding and the second feeding are injected into the mold cavity, and the start time of the second feeding injection is later than that of the first feeding injection, and after cooling and demolding, a porous ceramic green body is obtained;

[0074] The first feeding comprises 35-50wt% of quartz glass, 5-10wt% of complex phase additive, 20-40wt% of pore forming agent, 5-15wt% of sintering aid and 5-15wt% of binder;

[0075] The second feeding comprises 55-70wt% of quartz glass, 4-8wt% of complex phase additive, 5-15wt% of pore forming agent, 5-15wt% of sintering aid and 5-15wt% of binder.

[0076] The mesh number of the quartz glass is 250-350 mesh. Specifically, it is preferably 300 mesh.

[0077] The complex phase additive is a mixture of at least two of titanium oxide, yttrium oxide and zirconium oxide; wherein the mass ratio of titanium oxide to yttrium oxide is 1:1.1-1.5, and / or the mass ratio of titanium oxide to zirconium oxide is 1:1.1-1.5, and / or the mass ratio of yttrium oxide to zirconium oxide is 1:1.1-1.5.

[0078] The pore forming agent can be selected from one or a mixture of more than one of polyformaldehyde, polymethyl methacrylate and polystyrene.

[0079] The binder can be selected from one or a mixture of more than one of paraffin wax, ethylene-vinyl acetate copolymer and stearic acid.

[0080] The sintering aid can be selected from one or a mixture of more than one of glass powder, boron trioxide and barium carbonate.

[0081] When the first feeding is injected, the plasticizing temperature is 70-90℃, the rotating speed is 30-60rpm, and the injection speed is 30-50mm / s; when the second feeding is injected, the plasticizing temperature is 70-90℃, the rotating speed is 30-50rpm, and the injection speed is 10-30mm / s.

[0082] The first feeding is injected into the closed space of the base exterior 104 in the rear mold cavity 402 by the first injection machine cylinder 105, and the base exterior of the porous ceramic green body is formed, that is, the outer layer of the sintered porous ceramic; the first feeding is injected into the upper part of the feeding of the base exterior 104 in the rear mold cavity 402 by the second injection machine cylinder 205, and is tightly combined with the first feeding, so that the base interior of the porous ceramic green body is formed, that is, the inner layer of the sintered porous ceramic. Therefore, the mold cavity is the base exterior 104 in the rear mold cavity 402 of the porous ceramic sandwich injection molding device.

[0083] A porous ceramic,

[0084] The porous ceramic green body is obtained through debinding and sintering; the porous ceramic green body is prepared by the porous ceramic sandwich injection molding method described above.

[0085] In the debinding and sintering, the sintering is performed at a temperature rising rate of 200-230 DEG C / h to 880-920 DEG C, and then kept for 2-4 h, and then the temperature is raised to 1000-1200 DEG C at a temperature rising rate of 90-120 DEG C / h, and then kept for 2-4 h.

[0086] The first feeding and the second feeding are different, and the injection molding parameters, including the injection time interval before and after the feeding, the plasticizing temperature, etc., are also different, so that the inner layer of the porous ceramic prepared has a lower porosity and a smaller pore size, and the outer layer has a higher porosity and a larger pore size.

[0087] The present application can also be applied to the preparation of other structures of ceramic. In the preparation of other structures of ceramic, different feedings are used, and the injection molding parameters need to be adjusted according to the performance of the different feedings, so that the porous ceramic has different inner and outer layer structures under the condition of ensuring the tight combination of different feedings.

[0088] First, the compositions of the first feeding and the second feeding of samples 1-3 are as shown in Table 1.

[0089] Table 1 Composition of the first feeding and the second feeding of samples 1-3 ( / wt%)

[0090]

[0091]

[0092] The first feedstock and the second feedstock in samples 1-3 were prepared by the following method; specifically, the quartz glass powder, the composite additive were weighed, added into a three-dimensional mixer, mixed at a speed of 120 r / min for 4 hours, and then collected after mixing was completed. The pore-forming agent, the sintering aid, and the binder were then put into a banbury mixer and mechanically stirred at a temperature of 90°C for 4 hours, and then taken out and cooled and granulated to obtain the feedstock.

[0093] Meanwhile, the first feedstock and the second feedstock of comparative sample 1-8 were prepared according to sample 1, and the differences between comparative sample 1-8 and sample 1 are shown in Table 2.

[0094] Table 2 Differences between comparative sample 1-8 and sample 1

[0095]

[0096]

[0097] Example 1

[0098] The first feedstock and the second feedstock were used to prepare a porous ceramic green body, and then the porous ceramic was obtained by debinding and sintering.

[0099] (1) The granulated first feedstock and the second feedstock were added to the hopper of the injection molding machine and waited for injection.

[0100] The first feedstock injection process conditions; plasticizing temperature 70-90°C, speed 30-60 rpm, injection time 0.3-0.8 s, injection pressure 40 bar, injection speed 30-50 mm / s, holding pressure 20-50 bar, holding time 2-3 s, mold temperature 25-45°C, cooling time 10-15 s.

[0101] The second feedstock injection process conditions; plasticizing temperature 70-90°C, speed 30-50 rpm, injection time 0.5-1 s, injection pressure 20-40 bar, injection speed 10-30 mm / s, holding pressure 20-30 bar, holding time 2-3 s, mold temperature 25-45°C, cooling time 10-15 s.

[0102] (2) Injection molding operation:

[0103] S1 The first feedstock was injected into the mold cavity to 50-70%, i.e. the first feedstock injection time was 0.3-0.8 seconds, and then the second feedstock was injected.

[0104] Specifically, the first feedstock had not completely solidified when it entered the mold cavity, and only the molten feedstock that first contacted the surface of the mold cavity cooled down, which formed a very thin shell (similar to an eggshell).

[0105] S2The second melt feed is then pushed into the mold cavity by the injection machine through the barrel, and is wrapped by the first feed (similar to a sandwich cookie).

[0106] Then, after cooling and demolding, the ceramic green body tightly combined with the two feeds is obtained.

[0107] (3) The ceramic green body is placed in a sintering furnace for debinding and sintering, and is heated to 880-920°C at a heating rate of 200-230°C / h, kept for 2-4h, and then heated to 1000-1200°C at a heating rate of 90-120°C / h, kept for 2-4h.

[0108] Specifically, it is heated to 150°C at a rate of 30-40°C / h, kept for 2-3h, heated to 300°C at a rate of 45-55°C / h, kept for 2-3h, heated to 500°C at a rate of 60-75°C / h, kept for 4-6h, heated to 900°C at a rate of 200-230°C / h, kept for 2-4h, and heated to 1100°C at a rate of 90-120°C / h, kept for 2-4h, and then cooled to room temperature. Thus, the prepared porous ceramic is obtained.

[0109] Example 2

[0110] The first feed and the second feed of the granulated sample 1 are used to prepare a porous ceramic green body, and then debinding and sintering are performed to obtain a porous ceramic.

[0111] (1) The first feed and the second feed of the granulated sample 1 are added to the hopper of the injection machine for injection.

[0112] The first feed injection process conditions are: plasticizing temperature 80°C, rotation speed 30 rpm, injection time 0.5s, injection pressure 40 bar, injection speed 30 mm / s, holding pressure 20 bar, holding time 2s, mold temperature 30°C, and cooling time 10s.

[0113] The second feed injection process conditions are: plasticizing temperature 85°C, rotation speed 30 rpm, injection time 0.5-1s, injection pressure 30 bar, injection speed 20 mm / s, holding pressure 20 bar, holding time 2s, mold temperature 30°C, and cooling time 10s.

[0114] (2) Injection operation:

[0115] S1 When the first feed is injected into the mold cavity for 60% of the time, i.e. when the first feed injection time is 0.5s, the second feed starts to be injected.

[0116] Specifically, when the first feed enters the mold cavity, it has not yet completely solidified, and only the molten feed that first contacts the surface of the mold cavity cools first, at which time a very thin shell (similar to an eggshell) is formed.

[0117] S2 Then the second molten feed is pushed into the mold cavity by the barrel of the injection molding machine, which will be wrapped by the first feed (similar to a sandwich cookie).

[0118] Then, after cooling and demolding, the two kinds of feed are tightly combined to obtain a green ceramic body.

[0119] (3) Put the green ceramic body into the sintering furnace for debinding and sintering, specifically, heat to 150°C at 35°C / h, keep for 2.5h, heat to 300°C at 50°C / h, keep for 2.5h, heat to 500°C at 65°C / h, keep for 5h, heat to 900°C at 215°C / h, keep for 3h, heat to 1100°C at 110°C / h, keep for 3h, and cool to room temperature. Thus, the prepared porous ceramic is obtained.

[0120] The first feed and the second feed of Comparative Samples 1-8 are prepared by the preparation method of Example 2 to obtain the porous ceramic of Comparative Samples 1-8.

[0121] Example 3

[0122] The first feed and the second feed of the granulated Sample 2 are used to prepare a green porous ceramic body, and then debinding and sintering are performed to obtain a porous ceramic.

[0123] (1) The first feed and the second feed of the granulated Sample 2 are added to the hopper of the injection molding machine for injection molding.

[0124] The injection molding process conditions of the first feed are as follows: plasticizing temperature 70°C, rotation speed 60 rpm, injection time 0.5s, injection pressure 40 bar, injection speed 30 mm / s, holding pressure 20 bar, holding time 2s, mold temperature 30°C, and cooling time 10s.

[0125] The injection molding process conditions of the second feed are as follows: plasticizing temperature 70°C, rotation speed 50 rpm, injection time 0.5-1s, injection pressure 30 bar, injection speed 10 mm / s, holding pressure 20 bar, holding time 2s, mold temperature 30°C, and cooling time 10s.

[0126] (2) Injection molding operation:

[0127] S1 When the first feed is injected into the mold cavity for 50%, i.e., the first feed injection time is 0.3 seconds, the second feed starts to be injected.

[0128] Specifically, when the first feed enters the mold cavity, it has not yet completely solidified, and only the molten feed that first contacts the surface of the mold cavity cools first, at which time a very thin shell (similar to an eggshell) is formed.

[0129] S2 Then the second molten feed is pushed into the mold cavity by the barrel of the injection molding machine, which will be wrapped by the first feed (similar to a sandwich cookie).

[0130] Then, after cooling, the mold is demolded and the green ceramic body is ejected.

[0131] (3) The green ceramic body is placed in a sintering furnace for debinding and sintering. Specifically, the temperature is raised to 150°C at a rate of 35°C / h, maintained for 2.5 h, raised to 300°C at a rate of 50°C / h, maintained for 2.5 h, raised to 500°C at a rate of 65°C / h, maintained for 5 h, raised to 920°C at a rate of 230°C / h, maintained for 4 h, raised to 1200°C at a rate of 120°C / h, maintained for 2 h, and cooled to room temperature. Thus, the porous ceramic is obtained.

[0132] Example 4

[0133] The first feed and the second feed of the granulated sample 3 are used to prepare a green porous ceramic body, which is then debound and sintered to obtain a porous ceramic.

[0134] (1) The first feed and the second feed of the granulated sample 3 are added to the hopper of an injection molding machine for injection molding.

[0135] The first feed injection molding process conditions are as follows: plasticizing temperature 90°C, rotation speed 45 rpm, injection time 0.5 s, injection pressure 40 bar, injection speed 50 mm / s, holding pressure 20 bar, holding time 2 s, mold temperature 30°C, and cooling time 10 s.

[0136] The second feed injection molding process conditions are as follows: plasticizing temperature 90°C, rotation speed 45 rpm, injection time 0.5-1 s, injection pressure 30 bar, injection speed 30 mm / s, holding pressure 20 bar, holding time 2 s, mold temperature 30°C, and cooling time 10 s.

[0137] (2) Injection molding operation:

[0138] S1 When the first feed injection molding enters the mold cavity by 70%, i.e., the first feed injection time is 0.8 s, the second feed injection starts.

[0139] Specifically, when the first feed enters the mold cavity, it has not yet completely solidified, and only the molten feed that first contacts the surface of the mold cavity cools first, at which time a very thin shell (similar to an eggshell) is formed.

[0140] S2 Then, the second molten feed is pushed into the mold cavity by the barrel of the injection molding machine and is wrapped by the first feed (similar to a sandwich cookie).

[0141] Then, after cooling, the mold is demolded and the green ceramic body is ejected.

[0142] (3) Put the ceramic green body into the sintering furnace for debinding and sintering, specifically, increase the temperature to 150°C at a rate of 35°C / h, keep the temperature for 2.5 h, increase the temperature to 300°C at a rate of 50°C / h, keep the temperature for 2.5 h, increase the temperature to 500°C at a rate of 65°C / h, keep the temperature for 5 h, increase the temperature to 880°C at a rate of 200°C / h, keep the temperature for 2 h, increase the temperature to 1000°C at a rate of 90°C / h, keep the temperature for 4 h, and cool to room temperature. Thus, the prepared porous ceramic is obtained.

[0143] Meanwhile, according to the preparation method of Example 2, the feedstock of Comparative Sample 1 is used to prepare the porous ceramic of Comparative Example 1; the porous ceramics of Comparative Examples 2-8 are prepared by using the feedstock of Comparative Samples 2-8 respectively, and using the same preparation method as Example 2.

[0144] In addition, according to Example 2, Comparative Examples 9-13 are set up, and the differences between Comparative Examples 9-13 and Example 2 are shown in Table 3.

[0145] Table 3 Differences between Comparative Examples 9-13 and Example 2

[0146]

[0147] The porous ceramics prepared in Examples 2-4 and Comparative Examples 1-13 are subjected to performance tests, and the test results are shown in Tables 4-5.

[0148] Specifically, the appearance is visually inspected; the bending strength is detected by a three-point bending machine through a three-point bending test; the oil leakage resistance is detected by an oil leakage resistance test method; and the taste is evaluated by a professional product evaluator, wherein the taste is divided into three categories, and the total score is 10 points, good is 8-10 points, general is 6-8 points, and poor is less than 6 points.

[0149] In the three-point bending test, a standard size test piece is used to carry out the test, the distance between the fulcrums is 80±0.2mm, F; 5KG load is pressed at a rate of 5mm / min, and the bending stress is automatically calculated and displayed in a chart by the software TRAPEZIUM X according to the test force and test piece size.

[0150] The oil leakage resistance test method is as follows: a high-low temperature test box is used to carry out low temperature and high temperature tests on the product according to GB / T2423.1, 2 "Electrical and Electronic Products Environmental Test Test A: Low Temperature Test Method, Test B: High Temperature Test Method"; and the taste is evaluated by a professional product evaluator.

[0151] Table 4 Performance test results of Examples 2-4

[0152]

[0153] Table 5 Performance test results of Comparative Examples 1-13

[0154]

[0155]

[0156] From Tables 4-5, it can be seen that the porous ceramics prepared in Examples 2-4 have good effects in terms of appearance, bending strength, leakproofness, and use taste, and the effects are obviously improved compared with the porous ceramics prepared in the comparative examples; the prepared porous ceramics have good combination and high yield. Meanwhile, the preparation method is stable in process and easy to realize automation, and can meet mass production.

[0157] The above is only to further illustrate the technical content of the present application by way of examples, so that the reader can more easily understand, but not represent the embodiments of the present application is limited to this, any technical extension or re-creation made in accordance with the present application, are protected by the present application.

Claims

1. A porous ceramic sandwich injection molding method, characterized by, The method comprises the following steps: injecting a first feeding and a second feeding into a mold cavity, the second feeding being injected later than the first feeding, and then being cooled and demolded to obtain a porous ceramic green body; the first feeding comprises 35-50wt% of quartz glass, 5-10wt% of complex phase additive, 20-40wt% of pore forming agent, 5-15wt% of sintering aid, and 5-15wt% of binder; the second feeding comprises 55-70wt% of quartz glass, 4-8wt% of complex phase additive, 5-15wt% of pore forming agent, 5-15wt% of sintering aid, and 5-15wt% of binder; the complex phase additive is a mixture of at least two of titanium oxide, yttrium oxide and zirconium oxide; the mass ratio of titanium oxide to yttrium oxide is 1:1.1-1.5, and / or the mass ratio of titanium oxide to zirconium oxide is 1:1.1-1.5, and / or the mass ratio of yttrium oxide to zirconium oxide is 1:1.1-1.5; when the first feeding is injected, the plasticizing temperature is 70-90℃, the rotating speed is 30-60rpm, and the injection speed is 30-50mm / s; when the second feeding is injected, the plasticizing temperature is 70-90℃, the rotating speed is 30-50rpm, and the injection speed is 10-30mm / s.

2. The porous ceramic sandwich injection molding method according to claim 1, characterized by, The quartz glass has a mesh number of 250-350.

3. The porous ceramic sandwich injection molding method according to claim 1, characterized by, The pore forming agent can be selected from one or a mixture of more than one of polyoxymethylene, polymethyl methacrylate and polystyrene.

4. The porous ceramic sandwich injection molding method according to claim 1, characterized by, The binder can be selected from one or a mixture of more than one of paraffin, ethylene-vinyl acetate copolymer and stearic acid.

5. The porous ceramic sandwich injection molding method according to claim 1, wherein The sintering aid can be selected from one or a mixture of more than one of glass powder, boron trioxide and barium carbonate.

6. A porous ceramic sandwich injection molding apparatus for use in the porous ceramic sandwich injection molding method according to any one of claims 1 to 5, for injecting the first feed material and the second feed material into a mold cavity, characterized by, The device comprises a rear mold cavity, a front mold core, an injection molding machine cylinder and a flow channel device; one end of the flow channel device is fixedly connected with the rear mold cavity, and the other end penetrates through the front mold core and is connected with the injection molding machine cylinder; the injection molding machine cylinder comprises a first injection molding machine cylinder and a second injection molding machine cylinder, the flow channel device comprises a first flow channel device and a second flow channel device, the first injection molding machine cylinder is connected with the first flow channel device, and the second injection molding machine cylinder is connected with the second flow channel device.

7. The porous ceramic sandwich injection molding apparatus of claim 6, wherein, A base body is arranged outside the cavity of the rear mold cavity.

8. A porous ceramic, characterized by, The porous ceramic green body is obtained through debinding and sintering; the porous ceramic green body is prepared by the porous ceramic sandwich injection molding method in any one of claims 1-5; In the debinding and sintering, the sintering is performed at a temperature rising rate of 200-230℃ / h to 880-920℃, and then at a temperature rising rate of 90-120℃ / h to 1000-1200℃, and then the temperature is kept for 2-4h.

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