CN217392316U - High-temperature high-pressure synthesis device for diamond hard alloy composite sheet - Google Patents
High-temperature high-pressure synthesis device for diamond hard alloy composite sheet Download PDFInfo
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- CN217392316U CN217392316U CN202220757531.5U CN202220757531U CN217392316U CN 217392316 U CN217392316 U CN 217392316U CN 202220757531 U CN202220757531 U CN 202220757531U CN 217392316 U CN217392316 U CN 217392316U
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Abstract
The utility model relates to a high temperature high pressure synthesizer of compound piece of diamond carbide contains outer salt pipe, interior salt pipe and pyrophyllite, the pyrophyllite has the through-hole that is used for joining in marriage outer salt pipe and electrically conductive steel ring, outer salt union coupling is in it, join in marriage in the outer salt pipe and join in marriage the dress carbon pipe, join in marriage in the dress in the carbon pipe salt pipe, the metal cup is put into in the salt pipe, the port is packaged with the salt piece about, lower extreme repacking carbon piece and electrically conductive steel ring on the through-hole of pyrophyllite, carbon piece and outer salt pipe, the carbon pipe, interior salt pipe and salt piece are laminated mutually. When the device is applied, the carbon tube heats the inner salt tube and the outer salt tube simultaneously, and generates two isostatic pressing areas formed by molten salt, namely an inner isostatic pressing pool and an outer isostatic pressing pool, wherein the inner isostatic pressing pool provides a hot isostatic pressing environment which is suitable for sintering the diamond hard alloy composite sheet and has equal pressure in all directions, the outer isostatic pressing pool provides a pressure environment with even stress for the carbon tube in the outer isostatic pressing pool, and the stress of the carbon tube is balanced; the sintering quality of the diamond hard alloy composite sheet is obviously improved.
Description
Technical Field
The utility model relates to a synthesizer of compound piece of diamond carbide especially relates to a high temperature high pressure synthesizer under two pond hot isostatic pressing conditions.
Background
The diamond hard alloy composite sheet is formed by sintering diamond micro powder and a hard alloy base under the conditions of high temperature and high pressure, has the high hardness and the high wear resistance of diamond and the shock resistance of hard alloy, is used for manufacturing a diamond drill bit, and is finally used for exploration and exploitation of petroleum, natural gas and shale gas.
At present, the production process of the diamond hard alloy composite sheet comprises the following steps: firstly, acid and alkali purification treatment is carried out on diamond micro powder; secondly, sand blasting the surface of the hard alloy base to remove impurities; thirdly, filling the purified hard alloy base and the diamond micro powder into a high-melting-point metal cup; fourthly, the metal cup filled with the hard alloy base and the diamond micro powder is put into a vacuum furnace for high-temperature purification treatment; covering the metal cup after the purification treatment with a cover cup, and filling the metal cup into a synthetic block. Sixthly, placing the synthesized block into a cubic press to be sintered at high temperature and high pressure; and finally, processing the diamond hard alloy composite sheet obtained by sintering into a product meeting the commercialized requirement. When the cubic press works, high-pressure oil of 60-100 MPa is injected into an oil cylinder with the diameter of 500-850 mm to push six pistons to move towards the center, when a top hammer at the front part contacts six surfaces of a synthetic block (hexahedron), the synthetic block is extruded, high pressure required by synthesis is transferred through pyrophyllite, electricity for heating is transferred into a carbon sheet and a carbon tube through upper and lower conductive steel rings to heat the carbon sheet and the carbon tube, salt and a high-melting-point metal cup in the carbon tube are heated to 1400-1500 ℃, the salt is melted at high temperature, a solid phase is changed into a liquid phase, an isostatic pressure transfer environment is formed, and diamond micro powder and a hard alloy base wrapped by the high-melting-point metal cup in the cubic pressure transfer environment are sintered at the temperature of 1400-1500 ℃ and the pressure of 6-7 GPa. Because the applied pressure through the pyrophyllite conduction is very high, can make carbon piece and the carbon pipe that undertakes the heating effect take place to warp, cause heating field space distortion, influence the spatial uniformity in thermal field, and then influence the homogeneity of being heated of metal cup, finally make the interior diamond carbide compact of cup in the sintering process be heated unevenly, reduce its sintering quality.
SUMMERY OF THE UTILITY MODEL
The utility model aims at overcoming the deficiencies that prior art exists, providing a high temperature high pressure synthesizer of compound piece of diamond carbide, aim at improving the homogeneity that the high temperature of the compound piece of diamond carbide was heated.
The purpose of the utility model is realized through the following technical scheme:
the synthesis device of the diamond hard alloy composite sheet is characterized in that: contain outer salt pipe, interior salt pipe and pyrophyllite, the pyrophyllite has the through-hole that is used for joining in marriage outer salt pipe and conductive steel ring, and outer salt pipe is adorned in it, joins in marriage the dress carbon pipe in the outer salt pipe, joins in marriage the dress interior salt pipe in the carbon pipe, and in the interior salt pipe was put into to the metal cup, the port was packaged with the salt piece about last lower extreme, and carbon piece and conductive steel ring are gone into again to the through-hole upper and lower extreme of pyrophyllite, and the carbon piece is laminated mutually with outer salt pipe, carbon pipe, interior salt pipe and salt piece.
Further, according to the device for synthesizing the diamond hard alloy composite sheet, the inner salt tube is made of high-purity salt with NaCl purity higher than 99.5%.
Further, according to the device for synthesizing the diamond hard alloy composite sheet, the inner salt tube is formed by high-purity salt with the NaCl purity higher than 99.5% through cold isostatic pressing and high pressure forming, and the density of the inner salt tube is higher than 2.15g/cm 3 。
Further, the device for synthesizing the diamond hard alloy composite sheet comprises an inner salt tube, wherein the radial thickness of the inner salt tube is 2-5 mm.
Further, in the device for synthesizing the diamond hard alloy composite sheet, the outer salt pipe is formed by pressing NaCl and a heat-preservation powder material.
Further, the synthesis device of the diamond hard alloy composite sheet comprises 5-30% of the heat preservation powder material by mass.
Further, in the device for synthesizing the diamond hard alloy composite sheet, the heat-insulating powder material is Si 3 N 4 、CrO 2 Or AL 2 O 3 。
Further, the device for synthesizing the diamond hard alloy composite sheet comprises an outer salt tube, wherein the radial thickness of the outer salt tube is 2-5 mm.
Compared with the prior art, the utility model have apparent advantage and beneficial effect, the concrete aspect that embodies is in following:
the utility model discloses be equipped with interior salt pipe in the inboard of carbon pipe, the outside is equipped with outer salt pipe, and when the electric current passed through carbon pipe, the carbon pipe generates heat and heats interior salt pipe and outer salt pipe simultaneously, produces the isostatic pressing region that two molten salts formed simultaneously, promptly interior isostatic pressing pond and outer isostatic pressing pond, interior isostatic pressing pond provides one and is fit for the equal hot isostatic pressing environment of each direction pressure of the sintering of diamond carbide composite sheet; the outer isostatic pressing pool provides a pressure environment with uniform stress for the carbon tubes in the outer isostatic pressing pool, so that the geometric deformation of the carbon tubes is greatly reduced, the heating uniformity of the inner isostatic pressing pool is improved, and the sintering quality of the diamond hard alloy composite sheet is finally and remarkably improved; the outer salt tube also has the function of heat preservation for the heating carbon tube and the inner space, thereby reducing heat loss and heating energy consumption.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by the practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and drawings.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention, and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.
FIG. 1: the cross section structure of the device of the utility model is shown schematically;
FIG. 2: a microstructure photograph of the composite sheet of the comparative example;
FIG. 3: a microstructure photograph of the composite sheet of example 1.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. The components of embodiments of the present invention, as generally described and illustrated in the figures herein, may be arranged and designed in a wide variety of different configurations. Thus, the following detailed description of the embodiments of the present invention, presented in the accompanying drawings, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. Based on the embodiment of the present invention, all other embodiments obtained by the person skilled in the art without creative work belong to the protection scope of the present invention.
It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures. Meanwhile, in the description of the present invention, the directional terms and the sequence terms and the like are used only for distinguishing the description, and are not to be construed as indicating or implying relative importance.
As shown in fig. 1, the device for synthesizing the diamond hard alloy composite sheet comprises an outer salt tube 8, an inner salt tube 6 and a pyrophyllite 1, wherein the pyrophyllite 1 is provided with a through hole for assembling the outer salt tube 8 and a conductive steel ring 2, the outer salt tube 8 is arranged in the pyrophyllite, a carbon tube 5 is assembled in the outer salt tube 8, an inner salt tube 6 is assembled in the carbon tube 5, a metal cup 7 is placed in the inner salt tube 6, salt sheets 4 are packaged at the upper and lower ports, a carbon sheet 3 and a conductive steel ring 2 are assembled at the upper and lower ends of the through hole of the pyrophyllite 1, and the carbon sheet 3 is attached to the outer salt tube 8, the carbon tube 5, the inner salt tube 6 and the salt sheet 4.
Wherein the inner salt tube 6 is formed by high-purity salt with the NaCl purity higher than 99.5 percent through cold isostatic pressing and high pressure, and the density of the inner salt tube is higher than 2.15g/cm 3 And the radial thickness of the inner salt pipe 6 is 2-5 mm, so that a liquid salt pool formed after salt melting is ensured to fully wrap the high-melting-point metal cup inside.
The outer salt pipe 8 is formed by pressing NaCl and a heat-preservation powder material, the mass ratio of the heat-preservation powder material is 5-30%, and the heat-preservation powder material is Si 3 N 4 、CrO 2 Or AL 2 O 3 The radial thickness of the outer salt tube 8 is2-5 mm, so that the geometrical deformation of the carbon tube in the liquid salt pool formed after the outer salt tube is melted can be greatly reduced. The outer salt tube has good heat insulation performance, and can reduce heating energy consumption by 5-10%.
The synthesis process of the diamond hard alloy composite sheet comprises the following steps:
firstly, acid and alkali purification treatment is carried out on the diamond micro powder;
sand blasting to remove impurity on the surface of hard alloy base
Thirdly, filling the purified hard alloy base and the diamond micro powder into a metal cup;
fourthly, the metal cup with the hard alloy base and the diamond micro powder is put into a vacuum furnace for high-temperature purification treatment;
buckling a cover cup on the metal cup after purification treatment, inserting an outer salt pipe 8 into a hole of the pyrophyllite 1, sequentially filling a carbon tube 5, an inner salt pipe 6 and a metal cup 7, packaging a salt sheet 4, and putting a carbon sheet 3 and a conductive steel ring 2 into the upper end and the lower end of the hole of the pyrophyllite 1;
sixthly, after being assembled, the raw materials are placed into a cubic press to be sintered at high temperature and high pressure, and the sintering process comprises the following steps:
firstly, slowly pressurizing to 2-4 GPa;
then, starting heating, and leading current into the carbon sheets 3 and the carbon tubes 5 through the upper and lower conductive steel rings 2 to heat the carbon sheets and the carbon tubes to generate high temperature of 1400-1500 ℃;
the carbon tube 5 heats the inner salt tube 6 and the outer salt tube 8 at the same time, the inner salt tube and the outer salt tube are melted to generate an isostatic pressing area formed by two molten salts at the same time, an inner isostatic pressing pool and an outer isostatic pressing pool are formed, the inner isostatic pressing pool provides a isostatic pressing environment with equal pressure suitable for sintering the diamond hard alloy composite sheet, the outer isostatic pressing pool provides a pressure environment with uniform stress for the carbon tube in the outer isostatic pressing pool, the carbon tube 5 is balanced in stress and small in deformation, and the inner isostatic pressing pool generates a more balanced high-temperature and pressure environment; the carbon tube 5 and the inner space are also provided with heat preservation function, so that heat loss is reduced;
finally, continuously pressurizing to 6-7 GPa while maintaining high temperature, and sintering the diamond and the hard alloy in the high-melting-point metal cup 7;
and seventhly, releasing pressure, cooling to normal pressure and room temperature, and taking out the sintered diamond hard alloy composite sheet.
Comparative example
A single-salt-tube high-temperature high-pressure sintering process is adopted, a high-melting-point metal cup filled with diamond micro powder and hard alloy is placed into a salt tube, then a carbon tube for heating is sleeved on the outer surface of the inner salt tube, and a carbon sheet, a conductive steel ring and a pyrophyllite block for pressure transmission and sealing are placed up and down. Sintering at 1500 ℃ for 300 seconds under the condition of 6.5GPa, then stopping heating, cooling and slowly reducing the pressure to the state of room temperature and normal pressure, taking out the sintered body, and then machining and shaping to meet the commercialization requirement, thus finally obtaining the diamond hard alloy composite sheet.
Fig. 2 shows the heterogeneity of the microstructure of the composite sheet, which shows that, on one hand, the catalyst Co is more accumulated in a region with a higher temperature during sintering, and on the other hand, the abnormal phenomena of abnormal growth of WC grains and the like exist in the interface accessory of the hard alloy and the diamond, and the heterogeneous temperature causes the segregation of various components, thereby reducing the impact resistance and the heat resistance of the diamond hard alloy composite sheet.
Example 1
By adopting the double-salt tube structure of the utility model, the thickness of the inner salt tube is 5mm, high-purity salt is adopted, the purity of NaCl is not lower than 99.5 percent, and the density of the salt tube is 2.15g/cm 3; the thickness of the outer salt tube is 2mm, the components of the outer salt tube are 85% NaCl and 15% Cr2O3, the carbon tube is electrified to generate heat, and after reaching high temperature, the inner salt tube and the outer salt tube are melted to respectively form an inner isostatic pressing pool and an outer isostatic pressing pool; the outer isostatic pressing pool effectively controls the deformation of the heating carbon tube, so that the heating carbon tube is uniform in heating, the high-melting-point metal cup is uniformly heated through the inner isostatic pressing pool, the texture structure of the diamond hard alloy composite sheet obtained after high-temperature and high-pressure sintering is uniform, as shown in fig. 3, the segregation of Co without a catalyst is avoided, WC grains are not abnormally grown, the performance is improved, the hydrostatic strength of the composite sheet reaches Q2, and as shown in table 1, the heating power 6700W is reduced by 5% compared with the heating power used by the conventional single carbon tube.
Example 2
Adopt the double-salt tube structure, the thickness of the inner salt tube is 3.5mmHigh-purity salt is adopted, the purity of NaCl is not lower than 99.5%, and the density of a salt tube is 2.15g/cm 3; the thickness of the outer salt tube is 4mm, and the components of the outer salt tube are 90% NaCl and 10% AL 2 O 3 The carbon tube is electrified to generate heat, and after the carbon tube reaches high temperature, the inner salt tube and the outer salt tube are melted to form an inner isostatic pressing pool and an outer isostatic pressing pool respectively. The outer isostatic pressing pool effectively controls the deformation of the heating carbon tube, so that the heating carbon tube is uniformly heated, the high-melting-point metal cup is uniformly heated through the inner isostatic pressing pool, the diamond hard alloy composite sheet obtained after high-temperature and high-pressure sintering is uniform in tissue structure, the segregation of Co catalyst is avoided, WC grains are not abnormally grown, the performance is improved, the hydrostatic strength of the composite sheet reaches Q3, and as shown in Table 1, the used heating power of 6560W is 7% lower than that of the conventional single carbon tube.
Example 3
By adopting the double-salt tube structure of the utility model, the thickness of the inner salt tube is 2.5mm, high-purity salt is adopted, the purity of NaCl is not lower than 99.5 percent, and the density of the salt tube is 2.15g/cm 3; the thickness of the outer salt tube is 4.8mm, and the components of the outer salt tube are 92 percent of NaCl and 8 percent of Si 3 N 4 The carbon tube is electrified to generate heat, and after the carbon tube reaches high temperature, the inner salt tube and the outer salt tube are melted to form an inner isostatic pressing pool and an outer isostatic pressing pool respectively. The outer isostatic pressing pool effectively controls the deformation of the heating carbon tube, so that the heating carbon tube is uniformly heated, the high-melting-point metal cup is uniformly heated through the inner isostatic pressing pool, the diamond hard alloy composite sheet obtained after high-temperature and high-pressure sintering is uniform in tissue structure, the segregation of Co catalyst is avoided, WC grains are not abnormally grown, the performance is improved, the hydrostatic strength of the composite sheet reaches Q4, and as shown in Table 1, the heating power of 6350W is reduced by 10% compared with that of the conventional single carbon tube.
The magnitude of the force applied when the composite sheet was broken under the same conditions is shown in table 1, and the larger the value, the higher the strength.
TABLE 1
To sum up, the utility model is provided with an inner salt tube on the inner side of the carbon tube and an outer salt tube on the outer side, when the current passes through the carbon tube, the carbon tube generates heat and simultaneously heats the inner salt tube and the outer salt tube, and simultaneously generates two isostatic pressing areas formed by molten salt, namely an inner isostatic pressing pool and an outer isostatic pressing pool, wherein the inner isostatic pressing pool provides an environment which is suitable for the sintering of the diamond hard alloy composite sheet and has equal pressure in all directions; the outer isostatic pressing pool provides a pressure environment with uniform stress for the carbon tubes in the outer isostatic pressing pool, so that the geometric deformation of the carbon tubes is greatly reduced, the heating uniformity of the inner isostatic pressing pool is improved, and the sintering quality of the diamond hard alloy composite sheet is finally improved; the outer salt tube also has the function of heat preservation for the heating carbon tube and the inner space, thereby reducing heat loss and heating energy consumption.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined or explained in subsequent figures.
The above description is only for the specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto, and any person skilled in the art can easily think of the changes or substitutions within the technical scope of the present invention, and all should be covered within the protection scope of the present invention.
It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
Claims (3)
1. High temperature high pressure synthesizer of compound piece of diamond carbide, its characterized in that: contain outer salt pipe (8), interior salt pipe (6) and pyrophyllite (1), pyrophyllite (1) has the through-hole that is used for joining in marriage outer salt pipe (8) of dress and electrically conductive steel ring (2), outer salt pipe (8) are adorned in it, join in marriage in outer salt pipe (8) and join in marriage carbon pipe (5), join in marriage in carbon pipe (5) and join in marriage in salt pipe (6), in salt pipe (6) are put into in metal cup (7), upper and lower port is packaged with salt piece (4), carbon piece (3) and electrically conductive steel ring (2) are gone up to the lower extreme repacking in the through-hole of pyrophyllite (1), carbon piece (3) and outer salt pipe (8), carbon pipe (5), interior salt pipe (6) and salt piece (4) are laminated mutually.
2. The high-temperature high-pressure synthesis device of the diamond hard alloy composite sheet according to claim 1, characterized in that: the radial thickness of the inner salt tube (6) is 2-5 mm.
3. The high-temperature high-pressure synthesis device for the diamond hard alloy compact according to claim 1, characterized in that: the radial thickness of the outer salt pipe (8) is 2-5 mm.
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| CN202220757531.5U CN217392316U (en) | 2022-04-01 | 2022-04-01 | High-temperature high-pressure synthesis device for diamond hard alloy composite sheet |
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| CN202220757531.5U CN217392316U (en) | 2022-04-01 | 2022-04-01 | High-temperature high-pressure synthesis device for diamond hard alloy composite sheet |
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