A diamond synthesis device that facilitates temperature difference adjustment

Abstract

This utility model discloses a diamond synthesis device that facilitates temperature difference adjustment, relating to the field of diamond synthesis technology. It includes a sealed cavity, a heating system, and a heat preservation system. The sealed cavity consists of an upper conductive steel cap, a lower conductive steel cap, a pyrophyllite composite block, and a pyrophyllite ring. A molybdenum sheet connector is provided between the upper conductive steel cap and the upper heating plate. The heating system includes an upper heating plate and a lower heating plate. The heat preservation system includes an upper heat preservation plate and a lower heat preservation plate of uniform thickness. This invention solves the problems of a thick upper heat preservation plate significantly reducing the effective space within the synthesis cavity, and the limited thickness of the upper and lower heat preservation plates restricting the formation of a large temperature difference, thus affecting the diamond growth rate and making temperature adjustment inconvenient. Each time the temperature difference is adjusted, the size of the upper and lower heat preservation plates must be adjusted, which affects the size of the components within the synthesis cavity since the total size of the components is a fixed value, causing significant inconvenience in actual mass production.

Description

Technical Field

[0001] This utility model relates to the field of diamond synthesis technology, specifically to a diamond synthesis device that facilitates temperature difference adjustment. Background Technology

[0002] In conventional synthetic diamond production, the heating conductive plates at both ends are made of graphite paper or stainless steel sheets. Their main function is to conduct electricity, and they generate very little heat. The main heat source is the heating sleeve. Then, by using upper and lower insulation plates of different thicknesses, usually thicker at the top and thinner at the bottom, a higher temperature is created at the top of the synthesis chamber and a lower temperature is created at the bottom, thus meeting the temperature difference required for synthesis.

[0003] Currently, this method has several drawbacks: 1. The upper insulation plate is relatively thick, significantly reducing the effective space within the synthesis chamber. This has little impact on large presses, but a significant impact on small presses, making it difficult to synthesize diamonds larger than 20 carats in a small chamber. 2. Due to the limited thickness of the upper and lower insulation plates, the resulting temperature difference is also limited, making it difficult to create a large temperature difference and affecting the diamond growth rate. 3. Temperature adjustment is inconvenient. Each time the temperature difference is adjusted, the size of the upper and lower insulation plates must be adjusted. Since the total size of the components within the synthesis chamber is a fixed value, this will affect the size of the bulk components, which is very inconvenient in actual mass production and results in material waste. Utility Model Content

[0004] The purpose of this invention is to provide a diamond synthesis device that facilitates temperature difference adjustment. This addresses the problems of a thicker upper insulation plate, which significantly reduces the effective space within the synthesis chamber; limited thickness of the upper and lower insulation plates, which restricts the formation of a large temperature difference, thus affecting the diamond growth rate; and inconvenient temperature adjustment, requiring adjustment of the upper and lower insulation plates each time the temperature difference is adjusted. Since the total size of the components within the synthesis chamber is a fixed value, this affects the size of the components, causing inconvenience in actual mass production and resulting in material waste.

[0005] A diamond synthesis apparatus that facilitates temperature difference adjustment includes a sealed cavity, a heating system, and a heat preservation system. The sealed cavity is composed of an upper conductive steel cap, a lower conductive steel cap, a pyrophyllite composite block, and a pyrophyllite ring. A molybdenum sheet connector is provided between the upper conductive steel cap and the upper heating element. The heating system includes an upper heating element and a lower heating element. The heat preservation system includes an upper heat preservation sheet and a lower heat preservation sheet of the same thickness.

[0006] Preferably, the upper heating element and the lower heating element are both made by mixing and pressing zirconium oxide and graphite powder in a certain proportion, with zirconium oxide accounting for 30%-70% and graphite powder accounting for 70%-30%. The resistance value is adjusted by adjusting the ratio of zirconium oxide to graphite powder.

[0007] Preferably, the upper heating element is made of a mixture of 60% zirconium oxide and 40% graphite powder, which has a high resistance and a large heat output; the lower heating element is made of a mixture of 40% zirconium oxide and 60% graphite powder, which has a low resistance and a small heat output.

[0008] Preferably, the upper and lower insulation sheets are made of magnesium oxide and have a thickness of 5-8mm.

[0009] Preferably, the thickness of the upper and lower insulation sheets is 6mm, and the ratio of the thickness of the upper and lower heating sheets to the thickness of the lower heating sheet is 2:1.

[0010] Preferably, the diameter of the molybdenum sheet connector is 1.2 times the diameter of the heating element, and the thickness is 2-3 mm, which is used to improve the stability of the high-temperature resistance.

[0011] Preferably, the pressing pressure of the upper heating plate and the lower heating plate is 100-200T, the baking temperature is 100-150℃, and the baking time is 24 hours.

[0012] Preferably, the diameter of the upper conductive steel cap is larger than that of the lower conductive steel cap, and it is welded and fixed to the molybdenum sheet connector.

[0013] The advantages of this utility model are as follows: This utility model provides a diamond synthesis device that facilitates temperature difference adjustment. By adjusting the material ratio of the heating element, the temperature difference can be quickly adjusted without replacing the insulation element. The upper and lower insulation elements have the same thickness, freeing up effective space in the cavity and supporting the synthesis of large-sized diamonds with a small press. Attached Figure Description

[0014] Figure 1 This is a three-dimensional structural diagram of the present invention.

[0015] Figure 2 This is a cross-sectional view of the present invention.

[0016] Among them, 1. Upper conductive steel cap; 2. Lower conductive steel cap; 3. Pyrophyllite composite block; 4. Pyrophyllite ring; 5. Upper heating plate; 6. Lower heating plate; 7. Upper insulation plate; 8. Lower insulation plate; 9. Molybdenum sheet connector. Detailed Implementation

[0017] To make the technical means, creative features, objectives and effects of this utility model easier to understand, the present utility model will be further described below in conjunction with specific embodiments.

[0018] like Figures 1 to 2As shown, a diamond synthesis device that facilitates temperature difference adjustment includes a sealed cavity, a heating system, and a heat preservation system. The sealed cavity is composed of an upper conductive steel cap 1, a lower conductive steel cap 2, a pyrophyllite composite block 3, and a pyrophyllite ring 4. A molybdenum sheet connector 9 is provided between the upper conductive steel cap 1 and the upper heating element 5. The heating system includes an upper heating element 5 and a lower heating element 6. The heat preservation system includes an upper heat preservation element 7 and a lower heat preservation element 8 of the same thickness.

[0019] In the above scheme, the conductive steel cap 2 → lower insulation plate 8 → lower heating plate 6 → carbon source and seed layer 10 → upper heating plate 5 → upper insulation plate 7 → molybdenum sheet connector 9 → upper conductive steel cap 1 are stacked in sequence. The pyrophyllite composite block 3 and the pyrophyllite ring 4 are sealed and fixed. The lower conductive steel cap 2 is used to connect to the external power supply and its material is the same as that of the upper conductive steel cap.

[0020] In this embodiment, the upper heating element 5 and the lower heating element 6 are both made by mixing and pressing zirconium oxide and graphite powder in a certain proportion, with zirconium oxide accounting for 30%-70% and graphite powder accounting for 70%-30%. The resistance value is adjusted by adjusting the ratio of zirconium oxide to graphite powder.

[0021] In this embodiment, the upper heating element 5 is made of a mixture of 60% zirconium oxide and 40% graphite powder, resulting in high resistance and large heat generation; the lower heating element 6 is made of a mixture of 40% zirconium oxide and 60% graphite powder, resulting in low resistance and small heat generation.

[0022] In this embodiment, the pressing pressure of the upper heating element 5 and the lower heating element 6 is 100-200T, the baking temperature is 100-150℃, and the baking time is 24 hours.

[0023] In the above scheme, the heating element is prepared by using 200-mesh high-purity zirconium oxide (99.99%) and graphite powder (99.99%), mixed in the following proportions: upper heating element 560% zirconium oxide + 40% graphite, lower heating element 640% zirconium oxide + 60% graphite. The mixed powder is stirred evenly in a three-dimensional mixer for 2 hours. Equal amounts of powder are weighed and placed into a mold, and pressed into round pieces with a diameter of 50 mm and a thickness of 3 mm by a 200T press. After pressing, the pieces are placed in a 120℃ oven and baked for 24 hours to remove moisture.

[0024] In this embodiment, the upper insulation sheet 7 and the lower insulation sheet 8 are made of magnesium oxide and have a thickness of 5-8 mm.

[0025] In this embodiment, the thickness of the upper insulation sheet 7 and the lower insulation sheet 8 is 6mm, and the thickness ratio of the upper heating sheet 5 and the lower heating sheet 6 is 2:1.

[0026] In the above scheme, the upper insulation sheet 7 and the lower insulation sheet 8 have the same thickness, both 6mm. Compared with the traditional upper-thick and lower-thin design, the effective height of the cavity is increased by 15%-20%, supporting the synthesis of diamonds of 20 carats or more by small presses.

[0027] In this embodiment, the diameter of the molybdenum sheet connector 9 is 1.2 times the diameter of the heating sheet, and the thickness is 2-3 mm, which is used to improve the stability of the high-temperature resistance.

[0028] In this embodiment, the diameter of the upper conductive steel cap 1 is larger than that of the lower conductive steel cap 2, and it is welded and fixed to the molybdenum sheet connector 9.

[0029] In the above scheme, the molybdenum sheet connector 9 ensures the long-term stable operation of the high-resistance heating element.

[0030] Working Process and Principle: In use, this device first processes upper and lower heat-insulating sheets 7 and 8 of the same thickness. While maintaining a constant thickness, the resistance values ​​of the upper heating sheet 5 and lower heating sheet 6 are adjusted to change their heat generation. The upper heating sheet 5 and lower heating sheet 6 are made of zirconium oxide and graphite powder, mixed in a specific ratio and pressed into a circular shape. The specific ratio of zirconium oxide to graphite powder depends on the actual diamond growth rate required. When the growth rate is slow, the zirconium oxide content in the upper heating sheet 5 can be increased or the zirconium oxide content in the lower heating sheet 6 can be decreased, thereby increasing the resistance value of the upper heating sheet 5 or decreasing the resistance value of the lower heating sheet 6. This increases the heat generation of the upper heating sheet 5 or decreases the heat generation of the lower heating sheet 6, increasing the temperature difference between the upper and lower heating sheets. Conversely, a smaller temperature difference results in a slower diamond growth rate.

[0031] As is known from common technical knowledge, this utility model can be implemented through other embodiments that do not depart from its spirit or essential characteristics. Therefore, the disclosed embodiments described above are merely illustrative in all respects and are not the only ones. All modifications within the scope of this utility model or its equivalents are included in this utility model.

Claims

1. A diamond synthesis apparatus facilitating temperature differential adjustment, characterized by: It includes a sealed cavity, a heating system and a heat preservation system. The sealed cavity is composed of an upper conductive steel cap (1), a lower conductive steel cap (2), a pyrophyllite composite block (3) and a pyrophyllite ring (4). A molybdenum sheet connector (9) is provided between the upper conductive steel cap (1) and the upper heating plate (5). The heating system includes an upper heating plate (5) and a lower heating plate (6). The heat preservation system includes an upper heat preservation plate (7) and a lower heat preservation plate (8) of the same thickness.

2. A diamond synthesis apparatus for facilitating temperature differential adjustment as claimed in claim 1, wherein: The upper insulation sheet (7) and the lower insulation sheet (8) are made of magnesium oxide and have a thickness of 5-8mm.

3. A diamond synthesis apparatus for facilitating temperature differential adjustment as claimed in claim 2, wherein: The thickness of the upper insulation sheet (7) and the lower insulation sheet (8) is 6mm, and the thickness ratio of the upper heating sheet (5) and the lower heating sheet (6) is 2:

1.

4. A diamond synthesis apparatus for facilitating temperature differential adjustment as defined in claim 1, wherein: The diameter of the molybdenum sheet connector (9) is 1.2 times the diameter of the heating element, and the thickness is 2-3 mm. It is used to improve the stability of the high-temperature resistance.

5. A diamond synthesis apparatus for facilitating temperature differential adjustment as defined in claim 1, wherein: The pressing pressure of the upper heating plate (5) and the lower heating plate (6) is 100-200T, the baking temperature is 100-150℃, and the baking time is 24 hours.

6. A diamond synthesis apparatus for facilitating temperature differential adjustment as defined in claim 1, wherein: The upper conductive steel cap (1) has a larger diameter than the lower conductive steel cap (2) and is welded and fixed to the molybdenum sheet connector (9).

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