Porous composite synthesis structure for synthesizing gem-grade large single crystal
By using porous magnesium oxide composite ceramic rings and optimized heating components in the process of synthesis of diamonds, the problem of excessive carbonization of individual seeds is solved, the yield and quality of diamonds is improved, and better thermal conductivity, insulation and sealing conditions are achieved. .
Patent Information
- Application Number
- CN202421019755.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-11
- Publication Date
- 2025-01-14
- Estimated Expiration
- 2034-05-11
AI Technical Summary
In the process of synthesis of large single crystal diamonds, excessive carbonization of some seeds leads to excessive carburization of carbon sources, resulting in a large number of inclusions in the crystals, seriously affecting the quality and yield of diamonds.
Design a porous composite synthetic structure including a porous magnesium oxide composite ceramic ring that provides a separate growth space and catalyst for each seed, combining an optimized heating assembly and sealed pressure transfer dielectric layer to ensure appropriate thermal conductivity, insulation and sealing conditions .
It improves the yield rate of diamonds and is suitable for large-scale promotion, ensures the independent growth space and carbon source supply of each seed, and enhances the quality and yield of synthetic diamonds.
Smart Images
Figure CN222342796U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of artificial gemstone production equipment, and in particular relates to a porous composite synthesis structure for synthesizing gemstone-grade large single crystals. Background Art
[0002] Diamond has excellent mechanical, electrical, thermal and chemical properties and is widely used in oil drilling, stone processing, mechanical processing, electronics industry, aerospace, biosensors, semiconductors and quantum devices. In the superhard material manufacturing industry, the synthesis of gem-grade single crystals has become a technological development trend. Synthetic diamond is mainly synthesized using graphite as raw material and high temperature and high pressure technology. This technology mainly places graphite in a heating cavity constructed by a pressure-transmitting sealing device, and then realizes the phase change transformation of carbon elements by keeping the cavity warm and pressurized.
[0003] The existing patent CN117282352A discloses a method for preparing artificial diamonds. The raw material module as a whole is a square structure with a built-in cylindrical graphite raw material column and a sealed pressure-transmitting and heat-insulating medium wrapped outside. From the outside to the inside, its structure specifically includes: a heat-insulating and pressure-transmitting medium sleeve, a heating element, an insulating isolation layer, an outer graphite core column, an insulating isolation layer, and an inner graphite core column; wherein the inner graphite core column is embedded in the outer graphite core column to form an overall cylindrical graphite raw material column; the heat-insulating and pressure-transmitting medium sleeve is provided with a sealed pressure-transmitting medium layer outside; the raw material module for preparing carat-level diamonds has conductive steel rings in the middle of both ends of the module. During the growth and preparation process, the conductive steel rings at both ends and the heating element are used to form a heat conduction circuit. However, the problem between the preparation structure used in this preparation method and the general synthesis structure is that during the synthesis of large single crystals, the excess carbon source will be enriched in other areas due to the carbonization of individual crystal seeds. The excess carbon source will cause the carburization rate to be too fast, and the diamond will not have time to remove impurities during the growth process, resulting in more inclusions in the crystal, which not only seriously affects the quality and grade of the diamond, but also indirectly leads to a low diamond yield. Utility Model Content
[0004] In view of the technical problems existing in the structure of synthesizing large single crystals, the utility model proposes a porous composite synthetic structure for synthesizing gem-grade large single crystals, which has a reasonable design, provides a separate growth space as well as a catalyst and a carbon source for each crystal seed, and is conducive to improving the yield of synthetic diamonds.
[0005] In order to achieve the above-mentioned purpose, the technical solution adopted by the utility model is as follows: the utility model provides a porous composite synthesis structure for synthesizing gem-grade large single crystals, including a sealed pressure-transmitting medium layer, a heat-insulating pressure-transmitting medium sleeve, a large single crystal growth component and two groups of heating components arranged at both ends of the sealed pressure-transmitting medium layer, wherein the large single crystal growth component includes a porous magnesium oxide composite ceramic sleeve, each channel of the porous magnesium oxide composite ceramic sleeve is provided with a first high-purity graphite column, a first catalyst column, a second high-purity graphite column, a second catalyst column, a crystal blanket and a crystal seed distributed in sequence from top to bottom, a crystal bed matched with all the crystal seeds is provided at the bottom of the porous magnesium oxide composite ceramic sleeve, a samarium oxide insulating sheet and a samarium oxide insulating tube are respectively provided at the top and side of the large single crystal growth component, a nickel sheet is provided at the top of the samarium oxide insulating sheet and the bottom of the large single crystal growth component, and a barium oxide heat-insulating column is provided on the opposite sides of the two nickel sheets, and the two barium oxide heat-insulating columns constitute a heat-insulating accessory.
[0006] Preferably, the heating component includes a copper bowl with a plug, an alumina ceramic sheet and a dolomite sheet are arranged on the inner side of the copper bowl, a graphite heating sheet and a first iron sheet are arranged on the end of the copper bowl facing the large single crystal growth component, a magnesium oxide ring is arranged at the bottom of the first iron sheet, an iron column is arranged on the inner ring surface of the magnesium oxide ring, a second iron sheet is arranged at the bottom of the magnesium oxide ring, a graphite heating tube is arranged between the second iron sheets of the two heating components, and the graphite heating tube is sleeved on the outside of the large single crystal growth component and the thermal insulation accessory.
[0007] Preferably, the graphite heating sheet is a sheet structure cut from a high-purity graphite carbon rod, and has a thickness of 1.2 to 2 mm.
[0008] Preferably, the graphite heating tube is made of high-purity graphite carbon rods and turned into a tubular structure, and the tube wall thickness is 1 to 3 mm.
[0009] Preferably, a thermal insulation layer is provided between the graphite heating tube and the thermal insulation and pressure transmission medium sleeve.
[0010] Preferably, the thermal insulation layer comprises high-purity magnesium oxide tubes and magnesium oxide sheets.
[0011] Preferably, the sealing pressure transmission medium layer is a high-density composite pyrophyllite block.
[0012] Preferably, the inner end of the sealing pressure-transmitting medium layer is provided with a pyrophyllite ring and a dolomite ring which are nested with the heating component.
[0013] Compared with the prior art, the advantages and positive effects of the utility model are:
[0014] 1. The utility model provides a porous composite synthesis structure for synthesizing gem-grade large single crystals. The large single crystal growth component is based on a porous magnesium oxide composite ceramic ring, which provides a separate growth space, catalyst and carbon source for each crystal seed, so that the growth of other crystals will not be affected by the carbonization of individual crystal seeds. In addition, the heating component and large single crystal growth component provided by this product have good thermal conductivity, insulation and sealing conditions, which are conducive to improving the yield of synthetic diamonds and are suitable for large-scale promotion. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the following is a brief introduction to the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.
[0016] Figure 1 A schematic diagram of a porous composite synthesis structure for synthesizing gem-grade large single crystals provided in an embodiment;
[0017] Figure 2 A schematic diagram of the structure of a porous magnesium oxide composite ceramic ring provided in an embodiment;
[0018] In the above figures, 1. Sealing pressure transmission medium layer; 2. Insulating pressure transmission medium sleeve; 3. Large single crystal growth component; 31. Porous magnesium oxide composite ceramic sleeve ring; 32. First high-purity graphite column; 33. First catalyst column; 34. Second high-purity graphite column; 35. Second catalyst column; 36. Crystal blanket; 37. Crystal seed; 38. Crystal bed; 4. Heating component; 41. Plug copper bowl; 42. Alumina ceramic sheet; 43. Dolomite sheet; 44. Graphite heating sheet; 45. First iron sheet; 46. Magnesium oxide ring; 47. Iron column; 48. Second iron sheet; 49. Graphite heating tube; 5. Samarium oxide insulating sheet; 6. Samarium oxide insulating tube; 7. Nickel sheet; 8. Insulation accessories; 81. Barium oxide insulation column; 9. Insulation layer; 91. High-purity magnesium oxide tube; 10. Pyrophyllite ring; 11. Dolomite ring. DETAILED DESCRIPTION
[0019] In order to more clearly understand the above-mentioned purpose, features and advantages of the utility model, the utility model is further described below in conjunction with the accompanying drawings and embodiments. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict. For the convenience of description, if the words "upper", "lower", "left" and "right" appear below, they only indicate that the upper, lower, left and right directions are consistent with the drawings themselves, and do not limit the structure.
[0020] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways than those described herein. Therefore, the present invention is not limited to the specific embodiments of the following disclosure.
[0021] Examples, such as Figure 1 and Figure 2 As shown, the utility model provides a porous composite synthesis structure for synthesizing gem-grade large single crystals, including a sealed pressure-transmitting medium layer 1 arranged from the outside to the inside, a heat-insulating pressure-transmitting medium sleeve 2, a large single crystal growth component 3 and two groups of heating components 4 arranged at both ends of the sealed pressure-transmitting medium layer 1. On this basis, the large single crystal growth component 3 provided by the utility model includes a porous magnesium oxide composite ceramic ring 31, and each channel of the porous magnesium oxide composite ceramic ring 31 is provided with a first high-purity graphite column 32, a first catalyst column 33, a second high-purity graphite column 34, a second catalyst column 35, a crystal blanket 36 and a crystal seed 37 which are distributed in sequence from top to bottom. The bottom of the porous magnesium oxide composite ceramic ring 31 is provided with a crystal bed 38 matched with all the crystal seeds 37, and the top and side of the large single crystal growth component 3 are respectively provided with a samarium oxide insulating sheet 5 and a samarium oxide insulating tube 6, and the top of the samarium oxide insulating sheet 5 and the bottom of the large single crystal growth component 3 are both provided with a nickel sheet 7, and the opposite sides of the two nickel sheets 7 are provided with a barium arsenate insulation column 81, and the two barium arsenate insulation columns 81 constitute an insulation accessory 8.
[0022] In this product, the insulation accessory 8 is composed of two upper and lower barium carbonate insulation columns 81. The preparation method of barium carbonate is as follows: barium carbonate, calcium carbonate, zirconium dioxide and titanium dioxide are mixed in a certain proportion to obtain a mixture; the mixture is kept at 1100℃-1300℃ for 1-3 hours, crushed and ground to obtain barium carbonate powder, and then the barium carbonate powder is pressed into a column at a pressure of 50-100mpa; the high-barium carbonate insulation column is heated to 1500℃-1650℃ and kept warm for 3-5 hours; the thickness of the upper and lower barium carbonate insulation columns 81 is adjusted to ensure that the temperature of the crystal bed 38 is just in the appropriate diamond growth temperature range.
[0023] Further, the porous magnesium oxide composite ceramic collar 31 is a mixture of MgO and Al2O3 in a certain proportion, which is mixed by a three-dimensional mixer for 3-5 hours after mixing, and the obtained mixture is pressed into a composite ceramic column by a four-column press, with a pressing pressure of 25-35 MPa, and the obtained composite magnesium oxide column is baked in a high-temperature oven at 250°C-400°C for 8-10 hours, and the prepared composite magnesium oxide column is punched, with an outer wall thickness of 2-8 mm and a hole spacing of 2-6 mm, to obtain a porous magnesium oxide composite ceramic collar 31. As a separate space for diamond growth. The large single crystal growth component 3 is based on the porous magnesium oxide composite ceramic collar 31, providing a separate growth space, catalyst and carbon source for each seed crystal 37, so that the growth of other crystals will not be affected by the carbonization of individual seed crystals 37. At the same time, the insulation accessory 8 is used to insulate the heating environment of the heating component 4, providing better insulation and pressure conditions for the large single crystal, and the samarium oxide insulating sheet 5 and the samarium oxide insulating tube 6 provide better insulation and sealing conditions for the large single crystal growth component 3, which is beneficial to the growth of synthetic diamonds and to improving the yield of synthetic diamonds.
[0024] In order to improve the heating performance of the heating component 4, the heating component 4 provided by the utility model includes a plug copper bowl 41, an alumina ceramic sheet 42 and a dolomite sheet 43 are arranged on the inner side of the plug copper bowl 41, a graphite heating sheet 44 and a first iron sheet 45 are arranged on the end of the plug copper bowl 41 facing the large single crystal growth component 3, a magnesium oxide ring 46 is arranged at the bottom of the first iron sheet 45, an iron column 47 is arranged on the inner ring surface of the magnesium oxide ring 46, a second iron sheet 48 is arranged at the bottom of the magnesium oxide ring 46, a graphite heating tube 49 is arranged between the second iron sheets 48 of the two heating components 4, and the graphite heating tube 49 is sleeved on the outside of the large single crystal growth component 3 and the insulation accessory 8. Among them, the copper bowl 41 for conducting electricity adopts a bowl-shaped structure, and the alumina ceramic sheet 42 inside it has good conductivity, mechanical strength and high temperature resistance. At the same time, the dolomite sheet 43 has good fire resistance, which is beneficial to prolonging the actual service life of the copper bowl for plugging 41; the graphite heating sheet 44, the first iron sheet 45, the second iron sheet 48 and the graphite heating tube 49 play a heating role, and the continuity of the heating surface is good and the heating area is large, providing favorable heating conditions for the large single crystal growth component 3.
[0025] In order to improve the practicality of the graphite heating sheet 44, the graphite heating sheet 44 provided by the utility model is a sheet structure cut from a high-purity graphite carbon rod, and its thickness is 1.2-2 mm. The obtained graphite heating sheet 44 is vacuum-baked at a temperature of 1050-1200°C and a vacuum of 8×10-3 for 12-20 hours, and then cooled to room temperature for standby use.
[0026] In order to improve the utilization rate of the graphite heating tube 49, the graphite heating tube 49 provided by the utility model is made of a high-purity graphite carbon rod into a tubular structure, and the tube wall thickness is 1 to 3 mm. The obtained graphite heating tube 49 is vacuum baked at a temperature of 1050-1200°C and a vacuum of 8×10-3 for 12-20 hours, and then cooled to room temperature for standby use.
[0027] In order to improve the insulation of the inner side of the thermal insulation and pressure transmission medium sleeve 2, a thermal insulation layer 9 is arranged between the graphite heating tube 49 and the thermal insulation and pressure transmission medium sleeve 2, and the thermal insulation layer 9 provided by the utility model includes a high-purity magnesium oxide tube 91 and a magnesium oxide sheet. The magnesium oxide sheet can be wedged on the inner side of the high-purity magnesium oxide tube 91 with a thin sheet structure.
[0028] In order to improve the pressure transmission and heat preservation properties of the sealed pressure transmission medium layer 1, the sealed pressure transmission medium layer 1 provided by the utility model is a high-density composite pyrophyllite block, which is a high-density block formed by mixing and pressing South African pyrophyllite powder and Mentougou pyrophyllite in a certain proportion.
[0029] In order to improve the sealing and pressure retention properties of the product, the utility model provides a talc ring 10 and a dolomite ring 11 nested with the heating component 4 at the inner end of the sealing pressure transmission medium layer 1. The talc ring 10 and the dolomite ring 11 play a role of sealing and pressure retention on the one hand, and on the other hand, they can protect the heating component 4 to a certain extent, thereby extending the actual service life of the product.
[0030] The above description is only a preferred embodiment of the present invention and does not limit the present invention in other forms. Any technician familiar with the profession may use the technical content disclosed above to change or modify it into an equivalent embodiment with equivalent changes and apply it to other fields. However, any simple modification, equivalent change and modification made to the above embodiment based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the protection scope of the technical solution of the present invention.
Claims
1. A porous composite synthesis structure for synthesizing gem-grade large single crystals, comprising a sealed pressure-transmitting medium layer, a heat-insulating pressure-transmitting medium sleeve, a large single crystal growth assembly, and two sets of heating assemblies arranged at both ends of the sealed pressure-transmitting medium layer, characterized in that: The large single crystal growth component comprises a porous magnesium oxide composite ceramic ring, in each channel of the porous magnesium oxide composite ceramic ring there is provided a first high-purity graphite column, a first catalyst column, a second high-purity graphite column, a second catalyst column, a crystal blanket and a crystal seed which are sequentially distributed up and down, the bottom of the porous magnesium oxide composite ceramic ring is provided with a crystal bed which matches with all the crystal seeds, the top and the side of the large single crystal growth component are provided with a samarium oxide insulating sheet and a samarium oxide insulating tube respectively, the top of the samarium oxide insulating sheet and the bottom of the large single crystal growth component are provided with a nickel sheet, the opposite sides of the two nickel sheets are provided with a barium arsenate insulation column, and the two barium arsenate insulation columns constitute an insulation accessory.
2. The porous composite synthetic structure for synthesizing gem-grade large single crystals according to claim 1, characterized in that: The heating component includes a copper bowl with a plug, an alumina ceramic sheet and a dolomite sheet are arranged on the inner side of the copper bowl with a plug, a graphite heating sheet and a first iron sheet are arranged on the end of the copper bowl with a plug facing the large single crystal growth component, a magnesium oxide ring is arranged at the bottom of the first iron sheet, an iron column is arranged on the inner ring surface of the magnesium oxide ring, a second iron sheet is arranged at the bottom of the magnesium oxide ring, a graphite heating tube is arranged between the second iron sheets of the two heating components, and the graphite heating tube is sleeved on the outside of the large single crystal growth component and the thermal insulation accessory.
3. The porous composite synthetic structure for synthesizing gem-grade large single crystals according to claim 2, characterized in that: The graphite heating sheet is a sheet structure cut from a high-purity graphite carbon rod, and has a thickness of 1.2 to 2 mm.
4. The porous composite synthetic structure for synthesizing gem-grade large single crystals according to claim 3, characterized in that: The graphite heating tube is made of high-purity graphite carbon rods and turned into a tubular structure, and the tube wall thickness is 1 to 3 mm.
5. The porous composite synthetic structure for synthesizing gem-grade large single crystals according to claim 4, characterized in that: A thermal insulation layer is arranged between the graphite heating tube and the thermal insulation and pressure transmission medium sleeve.
6. The porous composite synthetic structure for synthesizing gem-grade large single crystals according to claim 5, characterized in that: The thermal insulation layer comprises a high-purity magnesium oxide tube and a magnesium oxide sheet.
7. The porous composite synthetic structure for synthesizing gem-grade large single crystals according to claim 1, characterized in that: The sealing pressure transmission medium layer is a high-density composite pyrophyllite block.
8. The porous composite synthetic structure for synthesizing gem-grade large single crystals according to claim 1, characterized in that: The inner end of the sealed pressure-transmitting medium layer is provided with a pyrophyllite ring and a dolomite ring which are nested with the heating component.