A sealed sintering device for polycrystalline diamond composite sheet

Abstract

The present invention belongs to the field of superhard composite materials, and in particular, relates to a sealed sintering device for polycrystalline diamond composite sheets, comprising a cup body with an open top, wherein the inner wall of the top of the cup body is radially and integrally extended with a flange, and the device also comprises a cup cover with an open bottom and used to seal the top opening of the cup body, and a welding agent layer is attached to the inner wall of the top of the cup cover, and when the cup cover and the cup body are assembled, the welding agent layer covers the top surface of the flange. The present invention provides a welding agent layer and performs vacuum and welding sealing treatment on the device before high-temperature and high-pressure sintering, so that the welding agent layer melts to seal the space between the cup cover and the cup body, thereby ensuring the consistency and stability of the space environment during the subsequent high-temperature and high-pressure sintering process, and preventing impurities and gases from mixing into the internal space of the diamond powder; at the same time, the vacuum treatment and welding sealing treatment are carried out simultaneously, which also improves the efficiency.

Description

Technical Field

[0001] The invention belongs to the field of superhard composite materials, and in particular relates to a sealing sintering device for a polycrystalline diamond composite sheet. Background Art

[0002] Polycrystalline diamond composite sheet is made of diamond powder and cemented carbide matrix through high temperature and high pressure. Because it not only has the high hardness, high wear resistance and thermal conductivity of diamond, but also has the strength and impact toughness of cemented carbide, it is an ideal material for manufacturing wear-resistant tools and is widely used in the fields of petroleum, geological drilling, etc.

[0003] High-end polycrystalline diamond composite sheets need to undergo high-temperature vacuum heat treatment and sealing treatment before high temperature and high pressure to increase the graphitization degree of diamond powder and remove internal impurities and air to improve internal stability. In the current composite sheet production process, most of them are subjected to high-temperature vacuum heat treatment after assembly, and sealing operations are performed after the heat treatment. The disadvantage of this method is that the diamond powder cannot be sealed in time, so that the internal environment of the diamond powder cannot be guaranteed, and there is a phenomenon of gas and impurities mixing, which reduces the overall performance of the polycrystalline diamond composite sheet. Summary of the invention

[0004] The object of the present invention is to provide a sealed sintering device for polycrystalline diamond composite sheets. The device of the present invention has a simple structure and can seal diamond powder before high-temperature and high-pressure sintering to prevent gas and impurities from mixing into it.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is as follows:

[0006] A sealed sintering device for a polycrystalline diamond composite sheet comprises a cup body with an open top, wherein the inner wall of the top of the cup body is radially extended with a flange, and the device also comprises a cup cover with an open bottom and used to seal the top opening of the cup body, wherein a welding agent layer is attached to the inner wall of the top of the cup cover, and when the cup cover and the cup body are assembled, the welding agent layer covers the top surface of the flange.

[0007] Preferably, a first insulating layer is gap-fitted in the cup body, and the first insulating layer covers the bottom surface of the flange and blocks the top notch of the cup body.

[0008] Preferably, the welding agent layer is arranged on the inner wall of the cup cover, and the axial height of the cup cover is 3-5 mm.

[0009] Preferably, a second insulating layer is gap-fitted in the cup cover, and the second insulating layer is arranged close to the bottom surface of the welding agent layer.

[0010] Preferably, a second insulating layer is further provided in the cup cover, and the second insulating layer is arranged close to the top and bottom surfaces of the welding agent layer and is gap-matched with the welding agent layer on the circumferential inner side wall of the cup cover.

[0011] Preferably, the insulating layer is a single substance, a mixture, an alloy or an alloy mixture of iron or niobium, such as a single substance of niobium, a niobium alloy, iron, an iron alloy, a niobium-iron mixture or a combination.

[0012] Preferably, the solder layer is made of an alloy or compound of copper, nickel, cobalt, gold, silver, manganese, palladium, titanium, niobium, zinc, phosphorus, boron, aluminum, cadmium, chromium, tin, silicon or tantalum.

[0013] The method for using the sealed sintering device of the polycrystalline diamond composite sheet comprises the following steps:

[0014] 1) Take a cup body with an open top, fill it with a layer of diamond powder and an alloy matrix first and then press it tightly, assemble the first insulating layer on the alloy matrix, press the open end of the top of the cup body to form a flange, and then assemble the cup cover with the top of the cup body;

[0015] 2) The device obtained in step 1) is heated to 1000-1200° C. in a vacuum environment to melt the solder layer.

[0016] Preferably, in step 1), before assembling the first insulating layer, aluminosilicate is sprayed on the top surface of the alloy substrate to form an aluminosilicate layer of 0.4-0.8 mm.

[0017] Compared with the prior art, the present invention has the following advantages:

[0018] 1) The present invention provides a welding agent layer and performs vacuum and welding sealing treatment on the device before high temperature and high pressure sintering, so that the welding agent layer melts to seal the space between the cup cover and the cup body, thereby ensuring the consistency and stability of the space environment during the subsequent high temperature and high pressure sintering process, and preventing impurities and gases from mixing into the internal space of the diamond powder; at the same time, the vacuum treatment and welding sealing treatment are carried out simultaneously, which also improves the efficiency.

[0019] 2) The device structure of the present invention is reasonably designed. The first and second insulating layers can effectively prevent molten solder from entering the inner space of the cup body and causing pollution. At the same time, the aluminosilicate layer plays a role in preventing adhesion, preventing the first insulating layer from adhering to the alloy substrate during the subsequent high-temperature and high-pressure sintering process. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic structural diagram of the sealed sintering device for the polycrystalline diamond composite sheet described in Example 1;

[0021] Figure 2This is a schematic structural diagram of the sealed sintering device for the polycrystalline diamond composite sheet described in Example 2. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0023] Example 1

[0024] A sealed sintering device for a polycrystalline diamond composite sheet includes a cup body 101 with an open top, wherein the inner wall of the top of the cup body 101 is radially extended and provided with a flange, and the device also includes a cup cover 108 with an open bottom and used to seal the top opening of the cup body, wherein a welding agent layer 107 is attached to the inner wall of the top of the cup cover 108, and when the cup cover 108 and the cup body are assembled, the welding agent layer 107 covers the top surface of the flange. The cup body 101 is also intermittently fitted with a first insulating layer 105 made of niobium, which covers the bottom surface of the flange and seals the top notch of the cup body 101.

[0025] A second insulating layer 106 made of niobium is also interspaced in the cup cover 108, and the second insulating layer 106 is arranged close to the bottom surface of the solder layer 107. The axial height of the cup cover 108 is 3-5 mm.

[0026] Example 2

[0027] A sealed sintering device for a polycrystalline diamond composite sheet includes a cup body 101 with an open top, wherein the inner wall of the top of the cup body 101 is radially extended and provided with a flange, and the device also includes a cup cover 108 with an open bottom and used to seal the top opening of the cup body, and a solder layer 107 is attached to the inner wall of the cup cover 108. When the cup cover 108 and the cup body are assembled, the solder layer 107 covers the outer wall of the top of the cup body 101. A first insulating layer 105 made of niobium is also intermittently fitted in the cup body 101, and the first insulating layer 105 covers the bottom surface of the flange and seals the top notch of the cup body 101.

[0028] The cup cover 108 is also provided with a second insulating layer 106 made of iron, which is arranged close to the top and bottom surfaces of the solder layer 107 and has a clearance fit with the solder layer 107 on the circumferential inner side wall of the cup cover 108. The axial height of the cup cover 108 is 3-5 mm.

[0029] The method of using the device described in Examples 1 and 2 is as follows:

[0030] 1) Take the cup body 101 with an open top, fill it with a layer of diamond powder 102 and an alloy matrix 103 first and then press it tightly, spray aluminosilicate on the top surface of the alloy matrix to form a 0.4-0.8 mm aluminosilicate layer 104, then install the first insulating layer 105 on the aluminosilicate layer 104, press the open end of the top of the cup body 101 to form a flange, and then install the cup cover 108 on the top of the cup body 107;

[0031] 2) The device obtained in step 1) is heated to 1000-1200° C. in a vacuum environment to melt the solder layer 107 .

Claims

1. A sealed sintering device for a polycrystalline diamond composite sheet, comprising a cup body with an open top, characterized in that: The inner wall of the top of the cup body is radially and integrally provided with a flange, the device also includes a cup cover with an open bottom and used to seal the open top of the cup body, a welding agent layer is attached to the inner wall of the top of the cup cover, and when the cup cover and the cup body are assembled, the welding agent layer covers the top surface of the flange; A first insulating layer made of niobium is also interstitially fitted in the cup body, the first insulating layer covers the bottom surface of the flange and blocks the top notch of the cup body; A second insulating layer made of niobium is also provided in the cup cover in a gap-fitted manner. The second insulating layer is arranged close to the bottom surface of the welding agent layer. The axial height of the cup cover is 3-5 mm.

2. A sealed sintering device for a polycrystalline diamond composite sheet, comprising a cup body with an open top, characterized in that: The inner wall of the top of the cup body is radially extended with a flange, the device also includes a cup cover with an open bottom and used to block the open top of the cup body, the inner wall of the cup cover is attached with a welding agent layer, and when the cup cover and the cup body are assembled, the welding agent layer covers the outer wall of the top of the cup body; the cup body is also gap-fitted with a first insulating layer made of niobium, the first insulating layer covers the bottom surface of the flange and blocks the top notch of the cup body; The cup cover is also provided with a second insulating layer made of iron, which is arranged close to the top and bottom surfaces of the welding agent layer and is gap-matched with the welding agent layer on the circumferential inner side wall of the cup cover; The axial height of the cup cover is 3-5 mm.

3. The sealed sintering device for polycrystalline diamond compact according to any one of claims 1 to 2, characterized in that: The solder layer is made of an alloy or compound of copper, nickel, cobalt, gold, silver, manganese, palladium, titanium, niobium, zinc, phosphorus, boron, aluminum, cadmium, chromium, tin, silicon or tantalum.

4. A method for using the sealed sintering device for a polycrystalline diamond compact according to any one of claims 1 to 3, characterized in that: Here are the steps: 1) Take a cup body with an open top, fill it with a layer of diamond powder and an alloy matrix first and then press it tightly, assemble the first insulating layer on the alloy matrix, press the open end of the top of the cup body to form a flange, and then assemble the cup cover with the top of the cup body; 2) The device obtained in step 1) is heated to 1000-1200° C. in a vacuum environment to melt the solder layer.

5. The method for using the sealed sintering device of the polycrystalline diamond composite sheet as claimed in claim 4, characterized in that, in step 1), before assembling the first insulating layer, aluminosilicate is sprayed onto the top surface of the alloy substrate to form an aluminosilicate layer of 0.4-0.8 mm.

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