A forming die for a zirconia porcelain block of a denture with clamping steps and a processing method thereof

Abstract

The application relates to the technical field of denture zirconia porcelain block forming, and discloses a denture zirconia porcelain block forming die with clamping steps and a processing method thereof, which comprises a female die, an upper die assembly, a bottom die assembly and two annular pressing dies, a forming cavity is arranged through the female die along a die pressing direction, the upper die assembly and the bottom die assembly are respectively arranged in the forming cavity in a sliding mode along the die pressing direction, the two annular pressing dies are respectively arranged on the opposite surfaces of the upper die assembly and the bottom die assembly, and the two annular pressing dies are respectively formed on the outer peripheral edges of the corresponding surfaces. According to the application, the powder is die pressed to form a green body by the upper die assembly and the bottom die assembly, and the two annular pressing dies are used to form step structures on the green body for the clamping disc of a tooth carving machine to be attached, so that the step of cutting off the excess powder is directly omitted compared with the prior art, the utilization rate of raw materials is greatly improved, the production cost is significantly reduced, the processing flow line is effectively simplified, and the production cycle of a single product is shortened.

Description

Technical Field

[0001] This application relates to the field of dental zirconia block molding technology, and in particular to a dental zirconia block molding mold with clamping steps and its processing method. Background Technology

[0002] Zirconia ceramics, with their excellent mechanical properties, natural aesthetic characteristics, and good biocompatibility, have become one of the main materials in the field of modern dental restoration.

[0003] In existing dental CAD / CAM processing, zirconia ceramic blocks for dentures typically require fixation and cutting using a specialized dental carving machine clamping disc. To ensure better fixation and a tighter fit between the zirconia ceramic block and the dental carving machine clamping disc, a stepped structure is usually provided on the outer peripheral edge of the ceramic block body for clamping.

[0004] Currently, the existing processing methods for stepped zirconia ceramic blocks are usually as follows: First, zirconia powder is compacted into a conventional round cylindrical blank using a common flat-head mold and press. Then, the blank is subjected to cold isostatic pressing for secondary densification and pre-sintering. After pre-sintering, the outer periphery of the blank, which has already been hardened, must be machined and polished using a CNC lathe or turning equipment to remove excess material, thereby processing the required clamping steps.

[0005] However, the aforementioned existing technologies have the following obvious drawbacks: 1. Serious waste of raw materials: The material at the step is removed by mechanical turning after pre-sintering. The removed zirconia powder is extremely difficult to recycle and reuse after sintering, resulting in low utilization of expensive zirconia raw materials. 2. Long processing cycle and low efficiency: An additional precision machining and grinding process is added, which greatly extends the overall production cycle of a single dental prosthesis block and increases the wear of turning tools and equipment maintenance costs.

[0006] Therefore, existing technologies still need improvement and development, and there is a lack of a device that can reduce material waste and processing cycles. Summary of the Invention

[0007] To address the shortcomings of existing technologies, this invention uses an upper mold assembly and a lower mold assembly to mold powder into a blank. At the same time, two annular pressing molds form a stepped structure on the blank for the clamping disc of the tooth carving machine to fit into. Compared with existing technologies, this invention directly eliminates the step of cutting off excess powder, significantly improves the utilization rate of raw materials, significantly reduces production costs, effectively simplifies the processing line, and shortens the production cycle of a single product.

[0008] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: a molding die for a dental zirconia block with clamping steps, comprising: a female mold, wherein a molding cavity is provided through the female mold along the molding direction, and the molding cavity is used to contain powder; Upper mold component; The bottom mold assembly, the upper mold assembly and the bottom mold assembly are respectively slidably disposed in the molding cavity along the molding direction, and the upper mold assembly and the bottom mold assembly are used to perform bidirectional or unidirectional molding of the powder in the molding cavity to form a blank; Two annular pressing molds are respectively disposed on the opposing surfaces of the upper mold assembly and the bottom mold assembly, and the two annular pressing molds are respectively formed on the outer peripheral edges of the corresponding surfaces, for forming a stepped structure at both ends of the blank after being compacted by the upper mold assembly and the bottom mold assembly in the molding direction for the clamping disc of the tooth carving machine to fit.

[0009] Furthermore, the two annular pressing molds are integrally formed on the upper mold assembly and the lower mold assembly, so that the opposing surfaces of the upper mold assembly and the lower mold assembly have a stepped structure with the center concave inward.

[0010] Furthermore, both the upper mold assembly and the bottom mold assembly include: an inner mold; An outer ring protruding mold is fitted onto the inner mold, and one end of the outer ring protruding mold in the molding direction protrudes from the pressing end face of the inner mold to form the annular pressing mold.

[0011] Furthermore, there is a preset distance between the two annular pressing dies to control the length of the stepped structure in the molding direction.

[0012] Furthermore, the female mold, the upper mold assembly, the bottom mold assembly, and the annular pressing mold are made of steel or aluminum alloy.

[0013] Furthermore, the dental zirconia ceramic block molding mold also includes: a plurality of venting micropores, wherein the plurality of venting micropores are respectively disposed through the upper mold assembly and the lower mold assembly, and the pore diameter of the venting micropores is smaller than the particle size of the powder.

[0014] A method for processing a zirconia ceramic block molding die with clamping steps as described above includes the following steps: loading powder into the molding cavity of the female mold, using the upper mold assembly and the bottom mold assembly to compact the powder under a press to form a blank, and using the annular pressing die at the edge of the upper mold assembly and the bottom mold assembly to integrally press the blank on both sides to form an initial preform with clamping steps. The initial preform after demolding is subjected to isostatic pressing to improve the overall density and uniformity of the initial preform. The isostatically pressed initial preform is sent into a sintering furnace for pre-sintering to form a finished zirconia ceramic block that does not require step turning.

[0015] Furthermore, in the step of "loading powder into the molding cavity of the female mold", a scraping device is used to make the surface of the powder loaded into the molding cavity convex parabolic shape with a high center and low edge, in order to compensate for the spatial volume difference caused by the annular pressing mold.

[0016] Furthermore, the powder is zirconium oxide powder or aluminum oxide powder.

[0017] Furthermore, the press is a unidirectional hydraulic press or a bidirectional hydraulic press.

[0018] Beneficial effects: The present invention uses an upper mold assembly and a lower mold assembly to mold powder into a blank, and at the same time uses two annular pressing molds to form a stepped structure on the blank for the clamping disc of the tooth carving machine to fit. Compared with the prior art, the step of cutting off excess powder is directly eliminated, the utilization rate of raw materials is greatly improved, the production cost is significantly reduced, and the processing line is effectively simplified and the production cycle of a single product is shortened. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of the dental zirconia ceramic block molding die provided by the present invention; in Figure 1 Figure (a) shows a schematic diagram of the structure of the zirconia ceramic block molding mold for dentures. Figure 1 Figure (b) is an exploded view of the structure of the zirconia ceramic block molding die for dentures; Figure 2 For the present invention Figure 1 A sectional view; Figure 3 For the present invention Figure 2 A magnified view of a portion of point A; Figure 4 A schematic diagram of the structure of a dental zirconia block molding die provided for another embodiment; in Figure 4 Figure (c) is a schematic diagram of the structure of the zirconia ceramic block molding die for dentures. Figure 4 Figure (d) is an exploded view of the structure of the zirconia ceramic block molding die for dentures; Figure 5 For the present invention Figure 4 A sectional view; Figure 6 This is a schematic diagram of the structure of the blank provided by the present invention.

[0020] The markings in the attached diagram are as follows: 100, female mold; 110, forming cavity; 200, upper mold assembly; 210, inner mold; 220, outer ring protruding mold; 300, bottom mold assembly; 400, ring pressing mold; 500, blank; 510, stepped structure. Detailed Implementation

[0021] This invention provides a molding die for a zirconia ceramic block for dentures with clamping steps and a processing method thereof. To make the objectives, technical solutions, and effects of this invention clearer and more explicit, the invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only for explaining the invention and are not intended to limit the invention.

[0022] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0023] It should also be noted that the same or similar reference numerals in the accompanying drawings of the embodiments of the present invention correspond to the same or similar components; in the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the accompanying drawings are only for illustrative purposes and should not be construed as limiting the present patent. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0024] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0025] The invention will be further explained below with reference to the accompanying drawings and the description of the embodiments.

[0026] This embodiment provides a zirconia ceramic block molding die with clamping steps. This die is mainly used for the pre-pressing of high-precision, high-density zirconia and other ceramic powders via dry pressing or cold isostatic pressing, and can press out a continuous solid blank 500 with a circumferential stepped structure 510 in one step. For example... Figures 1 to 6As shown, to solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: It includes a female mold 100, an upper mold assembly 200, a bottom mold assembly 300, and two annular pressing molds 400. The female mold 100 mainly serves as the outer pressure-bearing sleeve of the entire mold system. The interior of the female mold 100, along the molding direction (e.g., ... Figures 1 to 6 A forming cavity 110 is provided through the vertical direction of the prosthesis, which is used to contain inorganic non-metallic or metallic powder (preferably denture zirconia powder with a certain fluidity and loose packing density).

[0027] The upper mold assembly 200 and the bottom mold assembly 300 are respectively along the molding direction (e.g. Figures 1 to 6 The upper mold assembly 200 and the lower mold assembly 300 are slidably disposed within the molding cavity 110 (vertical direction). They are used to perform bidirectional or unidirectional molding of the powder within the molding cavity 110 to form a blank 500. Specifically, to achieve high-precision axial sliding, the outer diameter of the lower pressing section of the upper mold assembly 200 and the outer diameter of the rising section of the lower mold assembly 300 are respectively in transition fit or clearance fit with the inner wall of the molding cavity 110 to prevent locking due to excessively small gaps after frictional heating. The gap is required to be smaller than the particle size of the powder, preferably between 0.005 mm and 0.015 mm, to prevent powder leakage due to excessively large gaps. In actual production, this embodiment preferably uses bidirectional molding: while the upper mold assembly 200 applies downward pressure, the lower mold assembly 300 moves upward simultaneously, so that the frictional force within the powder is symmetrically distributed from both ends to the middle, reducing the density difference between the middle and both ends of the pressed blank 500, effectively reducing warping and deformation of the blank 500 during subsequent sintering.

[0028] Two annular pressing dies 400 are respectively disposed on the opposing surfaces (i.e., the pressing end faces that directly contact the powder) of the upper die assembly 200 and the bottom die assembly 300, and the two annular pressing dies 400 are respectively formed on the outer peripheral edges of the corresponding surfaces, for pressing the blank 500 after compaction by the upper die assembly 200 and the bottom die assembly 300 in the molding direction (e.g., ...). Figures 1 to 6The two ends of the die (in the vertical direction) form a stepped structure 510 for the dental carving machine's clamping disc to fit against. Specifically, by setting two annular pressing molds 400 on the outer periphery of the end face, when the upper mold assembly 200 and the lower mold assembly move relative to each other and apply pressure to the powder to the limit position, the annular pressing molds 400 also generate local pressure on the powder, causing the two ends of the final blank 500 to be directly concave, forming a 90-degree right-angled stepped structure 510 with standard depth and width, or a stepped structure 510 with a slight chamfer. This stepped structure 510 can achieve seamless rigid contact between surfaces with the U-shaped clamping disc or annular clamping fixture of a modern CAD / CAM five-axis dental carving machine. During the subsequent high-speed milling of the denture, even if subjected to large cutting impact forces, the porcelain block will not slip or rotate within the clamping disc, thus ensuring the processing accuracy of the denture.

[0029] In addition, in terms of specific structural design, to cope with the radial expansion stress under high pressure, the outer wall of the female mold 100 can adopt a reinforcing rib structure or be equipped with a double-layer prestressed outer sleeve to prevent fatigue cracking of the female mold 100 under long-term high-frequency stamping. The inner wall surface of the forming cavity 110 is preferably finely polished to reduce its surface roughness and decrease the frictional resistance between the powder and the wall surface of the forming cavity 110. The cross-sectional shape of the forming cavity 110 is set according to the specifications of the clamping plate of the mainstream dental carving machine on the market. In this embodiment, a standard cylindrical cavity is preferred to press a dental prosthesis ceramic block with a standard diameter of 98mm or 95mm.

[0030] In one embodiment, such as Figure 1 , Figure 2 as well as Figure 3 As shown, two annular pressing molds 400 are integrally formed on the upper mold assembly 200 and the bottom mold assembly 300, respectively, so that the opposing surfaces of the upper mold assembly 200 and the bottom mold assembly 300 have a stepped structure with the center concave inward. Specifically, the pressing end face of the upper mold assembly 200 is a rectangular or inverted trapezoidal stepped surface with a concave center and a convex outer edge, and the pressing end face of the bottom mold assembly 300 is a rectangular or regular trapezoidal stepped surface with a concave center and a convex outer edge. At the same time, the integral molding process can eliminate splicing gaps, avoid ultrafine powder from being embedded in tiny splicing gaps and affecting the production process, and improve the overall compressive strength, reducing the probability of edge chipping. It is suitable for the continuous industrial production of large batches of standardized zirconia ceramic blocks, which can further improve production efficiency and reduce production costs.

[0031] In one embodiment, to further improve the adjustability of the mold structure and the interchangeability of parts, and to reduce the processing cost of complex precision molds, the present invention also provides a split-type implementation. For example... Figure 4 , Figure 5As shown, both the upper mold assembly 200 and the bottom mold assembly 300 include: an inner mold 210 and an outer ring protruding mold 220. The outer ring protruding mold 220 is sleeved on the inner mold 210, and the outer ring protruding mold 220 is positioned in the molding direction (e.g., ...). Figures 1 to 6 One end of the outer ring protruding mold 220 protrudes from the pressing end face of the inner mold 210 to form an annular pressing mold 400. Specifically, the inner mold 210 is a solid cylinder, and the outer ring protruding mold 220 is a hollow annular body. The inner hole of the outer ring protruding mold 220 and the outer circumferential surface of the inner mold 210 are rigidly and coaxially assembled by heat fitting, pin fixing, or thread locking. It can be connected that the height of the end face of the outer ring protruding mold 220 protruding from the end face of the inner mold 210 is the length of the stepped structure 510 in the molding direction. Preferably, by adding precision adjusting shims of different thicknesses to the end of the outer ring protruding mold 220 away from the forming cavity 110, the height of the outer ring protruding mold 220 protruding from the end face of the inner mold 210 can be flexibly changed. Thus, without changing the entire set of molds, stepped ceramic blocks that are suitable for the clamping depth of different brands of dental carving machines can be pressed, realizing "one mold for multiple uses". In addition, due to the extremely high hardness of zirconia powder, the outer ring protruding mold 220 is subjected to great force and its edges are often the most susceptible to wear and tear from the powder. Once the wear exceeds the limit, technicians only need to replace the outer ring protruding mold 220 to achieve the recycling and regeneration of the entire mold, effectively reducing maintenance costs. In one embodiment, such as Figure 6 As shown, there is a preset gap between the two annular pressing dies 400 to control the stepped structure 510 in the molding direction (e.g., Figures 1 to 6 The preset spacing refers to the vertical distance between the opposite end faces of the annular pressing mold 400 on the upper mold assembly 200 and the annular pressing mold 400 on the lower mold assembly 300 when both the upper mold assembly 200 and the lower mold assembly 300 slide to the preset pressing dead point (at which point the pressure of the press reaches the maximum set value). The preset spacing is preferably 10mm.

[0032] In one embodiment, from the perspective of materials engineering and mold life, the female mold 100, upper mold assembly 200, bottom mold assembly 300, and ring pressing mold 400 are made of steel or aluminum alloy. In high-frequency industrial mass production lines requiring long service life, the female mold 100 and the upper and lower mold assemblies are preferably made of high-carbon, high-chromium wear-resistant mold steel (such as Cr12MoV, SKD11, or high-speed steel W6Mo5Cr4V2).

[0033] In one embodiment, a large amount of loose air exists between the zirconia powder particles. When rapidly subjected to high pressure within a closed mold cavity, if the gas cannot be properly released, localized high-pressure air pockets will form inside the blank 500. At the moment of pressure release and demolding, these residual high-pressure gases will expand rapidly, easily leading to serious defects such as delamination and internal microcracks in the blank 500. To address this technical problem, the dental zirconia block molding mold in this embodiment further includes several venting micropores, which are respectively disposed through the upper mold assembly 200 and the bottom mold assembly 300, and the pore diameter of the venting micropores is smaller than the particle size of the powder. Specifically, the venting micropores are arranged in an array on the pressing end face of the inner mold 210, or in an array on the stepped surface of the outer protruding mold 220. The pore diameter of the venting micropores is preferably 0.5 μm to 5 μm, and the average particle size of the powder used in this embodiment is preferably 30 μm to 50 μm. On a macroscopic level, because the pore size of the micropores is much smaller than the powder particle size, powder particles cannot pass through the micropores, thus effectively avoiding powder leakage and micropore blockage. On a microscopic level, high-pressure air can quickly and smoothly escape to the external back pressure surface of the mold through these dense micropore channels, avoiding the aforementioned problems. Preferably, to prevent powder from clogging the venting micropores during long-cycle molding, the venting micropores are structurally designed as tapered holes with a "small inner diameter and large outer diameter," meaning the diameter near the powder contact surface is in the micrometer range, while the diameter gradually increases to the millimeter range as it extends outwards. This ensures unidirectional and rapid airflow, significantly improving the internal density and product yield of the high-pressure molded ceramic block.

[0034] A method for processing a zirconia ceramic block molding die with clamping steps, as described above, utilizes a combination of dry pressing and cold isostatic pressing. This method not only achieves one-step, non-turning step fabrication but also completely solves the process problems of uneven step edge density and easy cracking during sintering. The method includes the following steps: Quantitative material application and powder shaping: The powder is loaded into the forming cavity 110 of the female mold 100; in this embodiment, the powder is zirconium oxide powder or aluminum oxide powder.

[0035] Dry pressing: The powder is compacted under a press by the upper mold assembly 200 and the bottom mold assembly 300 to form a blank 500. The annular pressing mold 400 on the edge of the upper mold assembly 200 and the bottom mold assembly 300 presses the blank 500 together on both sides to form an initial preform with clamping steps. Isostatic pressing: The initial preform after demolding is subjected to isostatic pressing to improve the overall density and uniformity of the initial preform; Pre-sintering: The initial preform after isostatic pressing is sent into the sintering furnace for pre-sintering to form finished zirconia blocks that do not require step turning.

[0036] In one embodiment, because the edges of the upper mold assembly 200 and the bottom mold assembly 300 have annular pressing molds 400 (i.e., protruding structures), the spatial volume at the edges is significantly smaller than that at the center when the mold is closed. If the powder surface is completely horizontal during loading, the powder at the edges will be subjected to excessive compression during pressing, resulting in excessively high edge density of the blank 500, and even edge cracking (chipping) due to stress concentration during demolding. To address this key technical problem, in the step of "loading powder into the molding cavity 110 of the female mold 100", a scraping device is used to make the surface of the powder loaded into the molding cavity 110 convex parabolic with a high center and low edges to compensate for the spatial volume difference caused by the annular pressing mold 400.

[0037] Specifically, the scraping device includes a metering scraper with a reverse parabolic arc edge. After the powder naturally accumulates and fills the forming cavity 110, the metering scraper sweeps laterally across the upper surface of the die 100, removing excess powder. Simultaneously, relying on the shaping effect of its arc edge, the powder surface inside the forming cavity 110 automatically presents a precise parabolic surface with a central bulge and gradually decreasing periphery. Preferably, the scraping device also includes a positioning structure, which can be positioned via the outer edge of the annular pressing mold 400, ensuring that the scraping device can only move radially along the annular pressing mold 400. In actual production, the parabolic surface with a central bulge and gradually decreasing periphery can be formed by repeatedly moving the scraping device laterally along different radial directions of the annular pressing mold 400.

[0038] In one embodiment, the press is a unidirectional hydraulic press or a bidirectional hydraulic press.

[0039] In summary, this application relates to the field of zirconia ceramic block molding technology for dentures, and discloses a molding die for zirconia ceramic blocks with clamping steps and its processing method. The die includes a female mold, an upper mold assembly, a bottom mold assembly, and two annular pressing molds. A molding cavity is formed through the female mold along the molding direction. The upper and bottom mold assemblies are slidably disposed within the molding cavity along the molding direction. The two annular pressing molds are respectively disposed on the opposite surfaces of the upper and bottom mold assemblies, and are formed on the outer periphery of their respective surfaces. This invention uses the upper and bottom mold assemblies to mold powder into a blank, and simultaneously uses the two annular pressing molds to form a stepped structure on the blank for the clamping disc of a dental carving machine to adhere to. Compared to existing technologies, this directly eliminates the step of cutting excess powder, significantly improving raw material utilization, significantly reducing production costs, and effectively simplifying the processing line and shortening the production cycle of a single product.

[0040] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A forming mold for a denture zirconia porcelain block with a clamping step, characterized by, include: A female mold, wherein a molding cavity is provided through the molded cavity along the molding direction, the molding cavity being used to contain powder; Upper mold component; The bottom mold assembly, the upper mold assembly and the bottom mold assembly are respectively slidably disposed in the molding cavity along the molding direction, and the upper mold assembly and the bottom mold assembly are used to perform bidirectional or unidirectional molding of the powder in the molding cavity to form a blank; Two annular pressing molds are respectively disposed on the opposing surfaces of the upper mold assembly and the bottom mold assembly, and the two annular pressing molds are respectively formed on the outer peripheral edges of the corresponding surfaces, for forming a stepped structure at both ends of the blank after being compacted by the upper mold assembly and the bottom mold assembly in the molding direction for the clamping disc of the tooth carving machine to fit.

2. The denture zirconia block forming mold with clamping step according to claim 1, characterized in that, The two annular pressing molds are integrally formed on the upper mold assembly and the lower mold assembly, so that the opposing surfaces of the upper mold assembly and the lower mold assembly have a stepped structure with the center concave inward.

3. The zirconia ceramic block molding die with clamping steps according to claim 1, characterized in that, Both the upper mold assembly and the bottom mold assembly include: an inner mold; An outer ring protruding mold is fitted onto the inner mold, and one end of the outer ring protruding mold in the molding direction protrudes from the pressing end face of the inner mold to form the annular pressing mold.

4. The zirconia ceramic block molding die with clamping steps according to claim 1, characterized in that, The two annular pressing dies have a preset spacing to control the length of the stepped structure in the molding direction.

5. The zirconia ceramic block molding die with clamping steps according to claim 1, characterized in that, The female mold, the upper mold assembly, the bottom mold assembly, and the annular pressing mold are made of steel or aluminum alloy.

6. The zirconia ceramic block molding die with clamping steps according to claim 1, characterized in that, The dental zirconia ceramic block molding mold further includes: a plurality of venting micropores, wherein the plurality of venting micropores are respectively disposed through the upper mold assembly and the lower mold assembly, and the pore diameter of the venting micropores is smaller than the particle size of the powder.

7. A method for processing a zirconia ceramic block molding die with clamping steps as described in any one of claims 1-6, characterized in that, The process includes the following steps: loading powder into the forming cavity of the female mold, using the upper mold assembly and the bottom mold assembly to compact the powder under a press to form a blank, and using the annular pressing mold at the edge of the upper mold assembly and the bottom mold assembly to integrally press the blank on both sides to form an initial preform with clamping steps. The initial preform after demolding is subjected to isostatic pressing to improve the overall density and uniformity of the initial preform. The isostatically pressed initial preform is sent into a sintering furnace for pre-sintering to form a finished zirconia ceramic block that does not require step turning.

8. A method for processing a zirconia ceramic block molding die with clamping steps as described in claim 7, characterized in that, In the step of "loading powder into the molding cavity of the female mold", a scraping device is used to make the surface of the powder loaded into the molding cavity convex parabolic shape with a high center and low edge, in order to compensate for the spatial volume difference caused by the annular pressing mold.

9. A method for processing a zirconia ceramic block molding die with clamping steps as described in claim 7, characterized in that, The powder is zirconium oxide powder or aluminum oxide powder.

10. A method for processing a zirconia ceramic block molding die with clamping steps as described in claim 7, characterized in that, The press is either a unidirectional or bidirectional hydraulic press.

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