Nitriding synthesis heat treatment equipment and process for preparing silicon nitride powder

Abstract

The invention belongs to the technical field of heat treatment equipment, and particularly relates to nitriding synthesis heat treatment equipment for preparing silicon nitride powder, which comprises a nitriding mechanism, the nitriding mechanism comprises a rectangular reaction furnace, the reaction furnace is provided with an upper opening and a lower opening, and the lower end of the reaction furnace is fixedly connected with four support legs distributed in a rectangular shape. Vertically arranged first hydraulic telescopic rods are fixedly mounted at the front end and the rear end of the reaction furnace; the silicon nitride powder preparation process adopts the nitridation synthesis heat treatment equipment for preparing the silicon nitride powder for preparation, and comprises the following steps: S1, driving the threaded rod to rotate through the first motor, driving the two moving rods to synchronously move leftwards, clamping the annular preparation disc through the two clamping blocks, and driving the annular preparation disc to move leftwards together. The device has the advantages that the annular preparation disc filled with silicon powder can be automatically moved into the reaction furnace for nitridation synthesis reaction and can be automatically taken out to effectively complete material taking work, the danger of manual scalding is avoided, and the preparation efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of heat treatment equipment, and in particular to a nitridation synthesis heat treatment equipment for preparing silicon nitride powder and a process thereof. Background Art

[0002] Silicon nitride is an important structural material with the characteristics of high hardness, wear resistance, large elastic modulus, high strength, high temperature resistance, small thermal expansion coefficient, large thermal conductivity, good thermal shock resistance, low density, small surface friction coefficient, good electrical insulation performance, etc. In terms of chemical properties, it also has the advantages of corrosion resistance and oxidation resistance.

[0003] The current method for preparing silicon carbide is to react silicon powder with nitrogen (or ammonia) at high temperature to generate silicon nitride. The starting temperature of the reaction is usually above 1200°C. This method requires the use of heat treatment equipment, but most of the existing heat treatment equipment is a closed heating furnace. Before preparation, the silicon powder needs to be placed in a specific container, and then the container is placed in the heating furnace for heating reaction with nitrogen (or ammonia), and then taken out after a certain period of reaction. However, due to its high melting point, the silicon nitride in the container is usually in a solid state when taken out of the reactor, and its volume will expand, and it cannot be easily taken out. It is necessary to manually use tools to hit the container to vibrate it out, which is time-consuming and labor-intensive, and there is a risk of burns.

[0004] In order to solve the above problems, we proposed a nitriding synthesis heat treatment equipment and process for preparing silicon nitride powder. Summary of the invention

[0005] The purpose of the present invention is to solve the problems in the background technology and to propose a nitriding synthesis heat treatment equipment and process for preparing silicon nitride powder.

[0006] In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a nitriding synthesis heat treatment equipment for preparing silicon nitride powder, comprising a nitriding mechanism, the nitriding mechanism comprising a rectangular reaction furnace, the reaction furnace is set with upper and lower openings, the lower end of the reaction furnace is fixedly connected to four support legs distributed in a rectangular shape, the front and rear ends of the reaction furnace are fixedly installed with vertically arranged first hydraulic telescopic rods, the telescopic ends of the two first hydraulic telescopic rods extend to the bottom of the reaction furnace and are fixedly connected to a fixed plate, a lifting bottom plate is fixedly connected between the two fixed plates, the upper end of the lifting bottom plate is fixedly connected to six support columns with uniform circumferential distribution, the upper ends of the six support columns are fixedly connected to an annular presentation plate, the upper end of the presentation plate is fixedly connected to two limit blocks spaced front and back and arranged laterally, an annular preparation plate is provided on the presentation plate, the lower end of the annular preparation plate is provided with a limit groove matching the two limit blocks, the two limit blocks are slidably connected in the corresponding limit grooves, the inner bottom wall of the annular preparation plate and at the corresponding positions of the two limit grooves are provided with circular holes, and the left and right ends of the annular preparation plate are fixedly connected to two limit columns spaced front and back;

[0007] The two sides of the reactor are provided with vertical plates at intervals, a sliding rod is fixedly connected between the two vertical plates, and a threaded rod is rotatably connected between the two vertical plates. The sliding rod is arranged in parallel with the threaded rod and is respectively arranged at the front and rear of the reactor, and two moving rods are jointly sleeved on the sliding rod and the threaded rod. A first motor that drives the threaded rod to rotate is fixedly installed on the vertical plate on the right side, the moving rod on the left side is arranged near the two supporting legs on the left side, and the moving rod on the right side is arranged near the vertical plate on the right side, the sliding rod passes through the two moving rods and is slidably connected thereto, the threaded rod passes through the two moving rods and is threadedly connected thereto, and the lower ends of the two moving rods are fixedly connected to the vertical plates, The annular preparation disk is clamped with arc-shaped clamping blocks on the left and right, and two sockets are horizontally provided on the two clamping blocks, and each of the limit columns is respectively inserted in the corresponding sockets. A damping shaft is commonly connected between the clamping block on the left and the vertical plate on the same side, and a rotating disk coaxially arranged with the damping shaft is rotatably connected to the vertical plate on the right, a telescopic cylinder is horizontally fixed and penetrated through the rotating disk, and the telescopic end of the telescopic cylinder is fixedly connected to the clamping block on the right, and a bevel gear ring concentrically arranged therewith is fixedly connected to the left end of the rotating disk, and a second motor is fixedly installed on the vertical plate on the right, and a bevel gear is fixedly sleeved on the output end of the second motor, and the bevel gear is vertically meshed with the bevel gear ring.

[0008] In the above-mentioned nitriding synthesis heat treatment equipment for preparing silicon nitride powder, a first electric heater is fixedly installed at the lower end of the lifting base plate, and the heating end of the first electric heater extends below the annular preparation disk. Second electric heaters are fixedly installed at both ends of the reaction furnace, and the heating ends of the two second electric heaters extend into the reaction furnace.

[0009] In the above-mentioned nitriding synthesis heat treatment equipment for preparing silicon nitride powder, movable circular blocks corresponding to the position and matching the size of the circular holes are vertically slidably inserted at the upper ends of the two limit blocks, and two first electric telescopic rods are fixedly installed at the lower end of the lifting base plate. The telescopic ends of the first electric telescopic rods pass through the corresponding support columns and the presentation plates and are fixedly connected to the corresponding lower ends of the movable circular blocks.

[0010] In the above-mentioned nitriding synthesis heat treatment equipment for preparing silicon nitride powder, a top plate is provided on the fixed cover at the upper end of the reactor, a second hydraulic telescopic rod is fixedly installed on the upper end of the top plate, the telescopic end of the second hydraulic telescopic rod passes through the top plate and is fixedly connected to an annular pressure plate in the reactor, and the rear end of the reactor is connected to an air injection pipe and an exhaust pipe.

[0011] In the above-mentioned nitriding synthesis heat treatment equipment for preparing silicon nitride powder, the upper end of the vertical plate located on the left side is fixedly connected to a fixing frame, and a second electric telescopic rod is fixedly installed vertically on the fixing frame. The telescopic end of the second electric telescopic rod is arranged downward and fixedly connected to a connecting plate, and the lower end of the connecting plate is fixedly connected to two top rods arranged at intervals front and back, and the two top rods have the same shape as the two circular holes and are equidistant from each other.

[0012] A process for preparing silicon nitride powder, using the above-mentioned nitridation synthesis heat treatment equipment for preparing silicon nitride powder, comprises:

[0013] S1. The threaded rod is driven to rotate by the first motor, and the two moving rods are driven to move to the left synchronously. The annular preparation disk is clamped by two clamping blocks and driven to move to the left together, so that the annular preparation disk is moved to the left side of the reactor, so as to load silicon powder into the annular preparation disk;

[0014] S2, the threaded rod is driven to rotate in the opposite direction by the first motor, and the two movable rods are driven to move to the right synchronously, so that the annular preparation plate is moved to the presentation plate again, so that the two circular holes are aligned with the two movable circular blocks, and then the two movable circular blocks are driven to insert into the corresponding circular holes by the two first electric telescopic rods, so as to block the circular holes and make them flush with the inner bottom wall of the annular preparation plate;

[0015] S3, control the telescopic cylinder to contract, drive the clamping block on the right to move right and away from the annular preparation disk, drive the threaded rod to rotate through the first motor, drive the two moving rods to move left, drive the clamping block on the left to move left and away from the annular preparation disk, at this time, both clamping blocks are in a state of being away from the annular preparation disk, and then the two first hydraulic telescopic rods are synchronously contracted, drive the lifting bottom plate to move up to the bottom of the reactor, seal the bottom of the reactor, and move the annular preparation disk into the reactor;

[0016] S4, start the second hydraulic telescopic rod, drive the annular pressing plate to press into the annular preparation disk and then move up and reset, so that the silicon powder in the annular preparation disk is evenly spread on the annular pressing plate, and then start the first electric heater and the two second electric heaters to heat the temperature in the reactor to a specified temperature, and continuously inject nitrogen into the reactor through the gas injection pipe to perform a nitridation synthesis reaction;

[0017] S5. After a certain period of nitriding synthesis reaction, the second hydraulic telescopic rod is started to drive the annular pressing plate to press into the annular preparation disk, press the silicon carbide in the annular preparation disk, squeeze out the excess gas inside, and then stop the heating work of the first electric heater and the two second electric heaters, and then move the annular preparation disk out of the reaction furnace through the first hydraulic telescopic rod to move it between the two clamping blocks;

[0018] S6, driving the threaded rod to rotate in the opposite direction through the first motor, controlling the two moving rods to move right, so that the clamping block on the left side contacts the annular preparation disk, and then starting the telescopic cylinder to drive the clamping block on the right side to contact the annular preparation disk, completing the clamping work of the annular preparation disk, and then controlling the two first electric telescopic rods to contract, moving the two movable round blocks downward out of the round hole, and then controlling the two moving rods to move left through the first motor, so that the annular preparation disk is moved to the left side of the reactor;

[0019] S7, the rotating disk is driven by the second motor to rotate half a circle, and then under the clamping action of the two clamping blocks, the annular preparation disk rotates half the axis at the same time, so that its opening is set downward, and at this time, the two push rods can be driven downward by the second electric telescopic rod to be inserted into the corresponding circular holes, so that the silicon nitride block in the annular preparation disk is pushed out of the annular preparation disk by the downward movement of the two push rods, and the removal of silicon nitride is completed;

[0020] S8, cooling the taken out silicon nitride block, crushing it after cooling, and performing powder making work.

[0021] Compared with the existing technology, the advantages of the nitriding synthesis heat treatment equipment and process for preparing silicon nitride powder are:

[0022] By setting up an annular preparation disk, a first electric heater and two second electric heaters, the heat generated by the first electric heater can directly act on the inner side of the annular preparation disk, so that it generates heat from the inside to the outside, and the heat generated by the two second electric heaters can act from both sides of the annular preparation disk toward the center, thereby effectively and evenly heating the silicon powder inside it.

[0023] After the synthesis reaction of silicon nitride is completed, the annular preparation disk is moved down out of the reactor by the first hydraulic telescopic rod, so that it moves to between the two clamping blocks, and the threaded rod is driven to rotate in the opposite direction by the first motor to control the two moving rods to move right, so that the clamping block on the left side contacts the annular preparation disk, and then the telescopic cylinder is started to drive the clamping block on the right side to contact the annular preparation disk, so as to complete the clamping work of the annular preparation disk, and then the two first electric telescopic rods are controlled to contract, and the two movable round blocks are moved downward out of the circular hole, and then the two moving rods are controlled to move left by the first motor to move the annular preparation disk to the left side of the reactor, and then the second motor drives the rotating disk to rotate half a circle, and then under the clamping action of the two clamping blocks, the annular preparation disk rotates half the axis at the same time, so that its opening is set downward, and at this time, the two push rods can be driven downward by the second electric telescopic rod to be inserted into the corresponding circular holes, so that the silicon nitride block in the annular preparation disk is pushed out of the annular preparation disk by the downward movement of the two push rods, and the removal of silicon nitride is completed, and the process is fully automated, which effectively avoids the risk of artificial scalding and improves the preparation efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a structural stereogram of a nitridation synthesis heat treatment device for preparing silicon nitride powder proposed by the present invention;

[0025] Figure 2 A structural stereogram from another perspective of a nitridation synthesis heat treatment device for preparing silicon nitride powder proposed by the present invention;

[0026] Figure 3 for Figure 2 The enlarged structural diagram at A in the middle;

[0027] Figure 4 A partial structural stereogram of a nitriding mechanism in a nitriding synthesis heat treatment device for preparing silicon nitride powder proposed by the present invention;

[0028] Figure 5 This is a structural stereogram of a lifting bottom plate in a nitriding synthesis heat treatment device for preparing silicon nitride powder proposed by the present invention;

[0029] Figure 6 A three-dimensional diagram of an annular preparation disk in a nitridation synthesis heat treatment device for preparing silicon nitride powder proposed by the present invention;

[0030] Figure 7A bottom-up stereoscopic view of an annular preparation disk in a nitridation synthesis heat treatment device for preparing silicon nitride powder proposed by the present invention;

[0031] Figure 8 This is a three-dimensional diagram of a placing plate in a nitriding synthesis heat treatment device for preparing silicon nitride powder proposed by the present invention.

[0032] In the figure: 1 reaction furnace, 2 support legs, 3 first hydraulic telescopic rod, 4 fixed plate, 5 lifting bottom plate, 6 support column, 7 presentation plate, 8 limit block, 9 annular preparation plate, 10 limit groove, 11 round hole, 12 movable round block, 13 first electric telescopic rod, 14 first electric heater, 15 limit column, 16 second electric heater, 17 top plate, 18 second hydraulic telescopic rod, 19 annular pressure plate, 20 gas injection pipe, 21 vertical plate, 22 slide rod, 23 threaded rod, 24 first motor, 25 moving rod, 26 vertical plate, 27 clamping block, 28 jack, 29 damping shaft, 30 rotating plate, 31 telescopic cylinder, 32 bevel gear ring, 33 second motor, 34 bevel gear, 35 fixed frame, 36 second electric telescopic rod, 37 top rod. DETAILED DESCRIPTION

[0033] The following examples are for illustrative purposes only and are not intended to limit the scope of the present invention.

[0034] Reference Figure 1-Figure 8 A nitriding synthesis heat treatment device for preparing silicon nitride powder includes a nitriding mechanism for preparing silicon nitride. The nitriding mechanism includes a rectangular reaction furnace 1, which is opened at the top and bottom. Four supporting legs 2 distributed in a rectangular shape are fixedly connected to the lower end of the reaction furnace 1. The front and rear ends of the reaction furnace 1 are fixedly installed with vertically arranged first hydraulic telescopic rods 3. The telescopic ends of the two first hydraulic telescopic rods 3 extend to the bottom of the reaction furnace 1 and are fixedly connected to a fixed plate 4. A lifting bottom plate 5 is fixedly connected between the two fixed plates 4. When the two first hydraulic telescopic rods 3 are synchronously extended and retracted, the lifting bottom plate 5 can be driven to rise and fall, thereby closing the lower end of the reaction furnace 1. Six support columns 6 with evenly distributed circumferences are fixedly connected to the upper end of the lifting bottom plate 5, and an annular presentation plate 7 is fixedly connected to the upper end of the six support columns 6. Two limit blocks 8 spaced front and back and arranged transversely are fixedly connected to the upper end of the presentation plate 7. An annular preparation plate 9 is arranged on the presentation plate 7, and a limit groove 10 matching the two limit blocks 8 is provided at the lower end of the annular preparation plate 9. The two limit blocks 8 are slidably connected in the corresponding limit grooves 10 to play a limiting role, so that the annular preparation plate 9 cannot move forward and backward on the presentation plate 7. Circular holes 11 are provided on the inner bottom wall of the annular preparation plate 9 and at the corresponding positions of the two limit grooves 10, and two limit columns 15 spaced front and back are fixedly connected at both left and right ends of the annular preparation plate 9.

[0035] A first electric heater 14 is fixedly installed at the lower end of the lifting base plate 5, and the heating end of the first electric heater 14 extends below the annular preparation disk 9. Second electric heaters 16 are fixedly installed at both ends of the left and right ends of the reaction furnace 1, and the heating ends of the two second electric heaters 16 extend into the reaction furnace 1. The first electric heater 14 and the second electric heater 16 are both prior arts and are not explained here. When the annular preparation disk 9 is moved into the reaction furnace 1, the heat generated by the first electric heater 14 can directly act on the inner side of the annular preparation disk 9, so that it generates heat from the inside to the outside, and the heat generated by the two second electric heaters 16 can act from both sides of the annular preparation disk 9 toward the center, thereby effectively and evenly heating the silicon powder inside it.

[0036] The upper ends of the two limit blocks 8 are vertically slidably inserted with movable circular blocks 12 corresponding to the position and matching the size of the circular holes 11. Two first electric telescopic rods 13 are fixedly installed at the lower end of the lifting base plate 5. The telescopic ends of the first electric telescopic rods 13 penetrate the corresponding support columns 6 and the presentation plates 7 and are fixedly connected to the lower ends of the corresponding movable circular blocks 12. The first electric telescopic rods 13 can drive the corresponding movable circular blocks 12 to be inserted into the corresponding circular holes 11, thereby blocking the circular holes 11.

[0037] The top fixed cover of the reactor 1 is provided with a top plate 17, and a second hydraulic telescopic rod 18 is fixedly installed on the top of the top plate 17. The telescopic end of the second hydraulic telescopic rod 18 penetrates the top plate 17 and is fixedly connected to an annular pressing plate 19 in the reactor 1. The rear end of the reactor 1 is connected to a gas injection pipe 20 and an exhaust pipe for inputting nitrogen. The second hydraulic telescopic rod 18 can drive the annular pressing plate 19 to move vertically.

[0038] Vertical plates 21 are arranged at intervals on both sides of the reactor 1, a sliding rod 22 is fixedly connected between the two vertical plates 21, a threaded rod 23 is rotatably connected between the two vertical plates 21, the sliding rod 22 and the threaded rod 23 are arranged in parallel and are respectively arranged at the front and rear of the reactor 1, two moving rods 25 are jointly sleeved on the sliding rod 22 and the threaded rod 23, a first motor 24 for driving the threaded rod 23 to rotate is fixedly installed on the vertical plate 21 on the right side, the moving rod 25 on the left side is arranged close to the two supporting legs 2 on the left side, and the moving rod 25 on the right side is arranged close to the vertical plate 21 on the right side, the sliding rod 22 passes through the two moving rods 25 and is slidably connected thereto, the threaded rod 23 passes through the two moving rods 25 and is threadedly connected thereto, and the first motor 24 can drive the threaded rod 23 to rotate, thereby driving the two moving rods 25 to move synchronously. The lower ends of the two moving rods 25 are fixedly connected to the vertical plates 26, and the annular preparation disk 9 is clamped with arc-shaped clamping blocks 27 on the left and right. Two sockets 28 are horizontally opened on the two clamping blocks 27, and each limit column 15 is respectively inserted into the corresponding socket 28. A damping shaft 29 is commonly connected between the clamping block 27 on the left and the vertical plate 26 on the same side. The damping shaft 29 is a prior art and can keep the clamping block 27 stable in position without being subjected to external forces. A rotating disk 30 coaxially arranged with the damping shaft 29 is rotatably connected to the vertical plate 26 on the right side, and a telescopic cylinder 31 is transversely fixedly passed through the rotating disk 30, and the telescopic end of the telescopic cylinder 31 is fixedly connected to the clamping block 27 on the right side, and the left end of the rotating disk 30 is fixedly connected to a bevel gear ring 32 coaxially arranged therewith, and a second motor 33 is fixedly installed on the vertical plate 21 on the right side, and a bevel gear 34 is fixedly sleeved on the output end of the second motor 33, and the bevel gear 34 is vertically meshed with the bevel gear ring 32, and the second motor 33 can drive the rotating disk 30 to rotate through the bevel gear 34 and the bevel gear ring 32, and the telescopic cylinder 31 also rotates with the rotating disk 30, thereby driving the annular preparation disk 9 to rotate through the two clamping blocks 27.

[0039] The upper end of the vertical plate 21 on the left side is fixedly connected to a fixing frame 35, and a vertically arranged second electric telescopic rod 36 is fixedly installed on the fixing frame 35. The telescopic end of the second electric telescopic rod 36 is arranged downward and fixedly connected to a connecting plate, and the lower end of the connecting plate is fixedly connected to two top rods 37 arranged at intervals front and back. The two top rods 37 have the same shape as the two circular holes 11 and are equidistant from each other. The second electric telescopic rod 36 can drive the two top rods 37 to move vertically.

[0040] A process for preparing silicon nitride powder, using the above-mentioned nitridation synthesis heat treatment equipment for preparing silicon nitride powder, comprises:

[0041] S1. The threaded rod 23 is driven to rotate by the first motor 24, driving the two moving rods 25 to move to the left synchronously, and the annular preparation disk 9 is clamped by two clamping blocks 27 and driven to move to the left together, so that the annular preparation disk 9 is moved to the left side of the reaction furnace 1, so as to load silicon powder into the annular preparation disk 9 (the silicon powder can be loaded avoiding the two round holes 11 to prevent the silicon powder from falling);

[0042] S2, the threaded rod 23 is driven to rotate in the opposite direction by the first motor 24, and the two movable rods 25 are driven to move to the right synchronously, so that the annular preparation plate 9 is moved to the presentation plate 7 again, so that the two circular holes 11 and the two movable circular blocks 12 are kept aligned, and then the two first electric telescopic rods 13 drive the two movable circular blocks 12 to be inserted into the corresponding circular holes 11, so as to block the circular holes 11 and make them flush with the inner bottom wall of the annular preparation plate 9;

[0043] S3, control the telescopic cylinder 31 to contract, drive the right clamping block 27 to move right and away from the annular preparation disk 9, drive the threaded rod 23 to rotate through the first motor 24, drive the two moving rods 25 to move left, drive the left clamping block 27 to move left and away from the annular preparation disk 9, at this time, both clamping blocks 27 are in a state of being away from the annular preparation disk 9, and then the two first hydraulic telescopic rods 3 are synchronously contracted, drive the lifting bottom plate 5 to move up to the bottom of the reaction furnace 1, seal the bottom of the reaction furnace 1, and move the annular preparation disk 9 into the reaction furnace 1;

[0044] S4, start the second hydraulic telescopic rod 18, drive the annular pressing plate 19 to press into the annular preparation disk 9 and then move upward to reset, so that the silicon powder in the annular preparation disk 9 is evenly spread in the annular pressing plate 19, and then start the first electric heater 14 and the two second electric heaters 16 to heat the temperature in the reactor 1 to a specified temperature, and continuously inject nitrogen into the reactor 1 through the gas injection pipe 20 to perform a nitridation synthesis reaction;

[0045] S5. After a certain period of nitriding reaction, the second hydraulic telescopic rod 18 is started to drive the annular pressing plate 19 to press into the annular preparation disk 9, to press the silicon carbide in the annular preparation disk 9, to squeeze out the excess gas inside, and then stop the heating work of the first electric heater 14 and the two second electric heaters 16, and then move the annular preparation disk 9 down out of the reaction furnace 1 through the first hydraulic telescopic rod 3, so that it moves between the two clamping blocks 27;

[0046] S6, drive the threaded rod 23 to rotate in the opposite direction through the first motor 24, control the two moving rods 25 to move right, so that the clamping block 27 on the left side contacts the annular preparation disk 9, and then start the telescopic cylinder 31 to drive the clamping block 27 on the right side to contact the annular preparation disk 9, and complete the clamping work of the annular preparation disk 9, then control the two first electric telescopic rods 13 to contract, move the two movable round blocks 12 downward out of the circular hole 11, and then control the two moving rods 25 to move left through the first motor 24, and move the annular preparation disk 9 to the left side of the reaction furnace 1;

[0047] S7, the rotating disk 30 is driven to rotate half a circle by the second motor 33, and then under the clamping action of the two clamping blocks 27, the annular preparation disk 9 rotates half the axis at the same time, so that its opening is set downward, and at this time, the two push rods 37 can be driven to move downward by the second electric telescopic rod 36 and inserted into the corresponding circular holes 11, so that the silicon nitride blocks in the annular preparation disk 9 are pushed out of the annular preparation disk 9 by the downward movement of the two push rods 37, and the silicon nitride removal work is completed (after the removal work is completed, the annular preparation disk 9 only needs to be rotated again to the state where the opening faces upward, and silicon powder can be added therein again, so as to carry out the next silicon nitride preparation work);

[0048] S8, cooling the taken out silicon nitride block, crushing it after cooling, and performing powder making work.

[0049] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A nitriding synthesis heat treatment device for preparing silicon nitride powder, comprising a nitriding mechanism, characterized in that: The nitriding mechanism comprises a rectangular reaction furnace (1), the reaction furnace (1) is provided with upper and lower openings, the lower end of the reaction furnace (1) is fixedly connected to four support legs (2) distributed in a rectangular shape, the front and rear ends of the reaction furnace (1) are both fixedly installed with vertically arranged first hydraulic telescopic rods (3), the telescopic ends of the two first hydraulic telescopic rods (3) both extend to the bottom of the reaction furnace (1) and are fixedly connected to a fixed plate (4), a lifting bottom plate (5) is fixedly connected between the two fixed plates (4), the upper end of the lifting bottom plate (5) is fixedly connected to six support columns (6) with uniform circumferential distribution, and the upper ends of the six support columns (6) are A circular presentation plate (7) is fixedly connected together, and two limit blocks (8) are fixedly connected to the upper end of the presentation plate (7) and are arranged horizontally and spaced from each other. An annular preparation plate (9) is provided on the presentation plate (7), and a limit groove (10) matching the two limit blocks (8) is provided at the lower end of the annular preparation plate (9). The two limit blocks (8) are slidably connected in the corresponding limit grooves (10). Circular holes (11) are provided on the inner bottom wall of the annular preparation plate (9) and at corresponding positions of the two limit grooves (10). Two limit posts (15) spaced from each other are fixedly connected to the left and right ends of the annular preparation plate (9); Vertical plates (21) are arranged at intervals on both sides of the reaction furnace (1), a sliding rod (22) is fixedly connected between the two vertical plates (21), a threaded rod (23) is rotatably connected between the two vertical plates (21), the sliding rod (22) and the threaded rod (23) are arranged in parallel and are respectively arranged at the front and rear of the reaction furnace (1), two moving rods (25) are sleeved on the sliding rod (22) and the threaded rod (23), a first motor (24) for driving the threaded rod (23) to rotate is fixedly installed on the vertical plate (21) located on the right side, the moving rod (25) located on the left side is arranged near the two supporting legs (2) on the left side, and the moving rod (25) located on the right side is arranged near the vertical plate (21) on the right side, the sliding rod (22) passes through the two moving rods (25) and is slidably connected thereto, the threaded rod (23) passes through the two moving rods (25) and is threadedly connected thereto, the lower ends of the two moving rods (25) are fixedly connected to the vertical plates (26), and the vertical plates (26) are fixedly connected to the two moving rods (25). The annular preparation disk (9) is provided with arc-shaped clamping blocks (27) on both sides, and two insertion holes (28) are horizontally provided on the two clamping blocks (27). Each of the limit posts (15) is inserted into the corresponding insertion holes (28). A damping shaft (29) is commonly connected between the clamping block (27) on the left side and the vertical plate (26) on the same side. A rotating disk (30) coaxially arranged with the damping shaft (29) is rotatably connected to the vertical plate (26) on the right side. A telescopic cylinder (31) is transversely fixedly passed through the movable plate (30), the telescopic end of the telescopic cylinder (31) is fixedly connected to a clamping block (27) located on the right side, the left end of the rotating plate (30) is fixedly connected to a concentrically arranged bevel gear ring (32), a second motor (33) is fixedly mounted on the vertical plate (21) located on the right side, the output end of the second motor (33) is fixedly sleeved with a bevel gear (34), and the bevel gear (34) is vertically meshed with the bevel gear ring (32).

2. The nitriding synthesis heat treatment equipment for preparing silicon nitride powder according to claim 1, characterized in that: A first electric heater (14) is fixedly mounted at the lower end of the lifting base plate (5), and a heating end of the first electric heater (14) extends below the annular preparation plate (9). Second electric heaters (16) are fixedly mounted at both left and right ends of the reaction furnace (1), and heating ends of the two second electric heaters (16) extend into the reaction furnace (1).

3. The nitriding synthesis heat treatment equipment for preparing silicon nitride powder according to claim 1, characterized in that: The upper ends of the two limit blocks (8) are vertically slidably inserted with movable round blocks (12) corresponding to the positions of the round holes (11) and matching in size. The lower end of the lifting base plate (5) is fixedly installed with two first electric telescopic rods (13). The telescopic ends of the first electric telescopic rods (13) penetrate the corresponding support columns (6) and the placing plate (7) and are fixedly connected to the lower ends of the corresponding movable round blocks (12).

4. The nitriding synthesis heat treatment equipment for preparing silicon nitride powder according to claim 1, characterized in that: The upper fixed cover of the reaction furnace (1) is provided with a top plate (17), the upper end of the top plate (17) is fixedly mounted with a second hydraulic telescopic rod (18), the telescopic end of the second hydraulic telescopic rod (18) passes through the top plate (17) and is fixedly connected to an annular pressing plate (19) in the reaction furnace (1), and the rear end of the reaction furnace (1) is connected to a gas injection pipe (20) and an exhaust pipe.

5. The nitriding synthesis heat treatment equipment for preparing silicon nitride powder according to claim 1, characterized in that: The upper end of the vertical plate (21) located on the left side is fixedly connected to a fixing frame (35), and a second electric telescopic rod (36) arranged vertically is fixedly installed on the fixing frame (35). The telescopic end of the second electric telescopic rod (36) is arranged downward and fixedly connected to a connecting plate, and the lower end of the connecting plate is fixedly connected to two top rods (37) arranged at a front-to-back interval, and the two top rods (37) have the same shape as the two circular holes (11) and are spaced at equal intervals.

6. A process for preparing silicon nitride powder, using a nitridation synthesis heat treatment device for preparing silicon nitride powder according to any one of claims 1 to 5, characterized in that: include: S1. The threaded rod (23) is driven to rotate by the first motor (24), thereby driving the two moving rods (25) to move synchronously to the left, and the annular preparation disk (9) is clamped by two clamping blocks (27) and driven to move to the left together, so that the annular preparation disk (9) is moved to the left side of the reaction furnace (1), thereby loading silicon powder into the annular preparation disk (9); S2, the threaded rod (23) is driven to rotate in the opposite direction by the first motor (24), so that the two movable rods (25) are driven to move to the right synchronously, thereby moving the annular preparation plate (9) onto the presentation plate (7) again, so that the two circular holes (11) and the two movable circular blocks (12) are kept aligned, and then the two movable circular blocks (12) are driven to be inserted into the corresponding circular holes (11) by the two first electric telescopic rods (13), so as to block the circular holes (11) and be flush with the inner bottom wall of the annular preparation plate (9); S3, control the telescopic cylinder (31) to contract, drive the clamping block (27) on the right side to move right and detach from the annular preparation disk (9), drive the threaded rod (23) to rotate through the first motor (24), drive the two moving rods (25) to move left, drive the clamping block (27) on the left side to move left and detach from the annular preparation disk (9), at this time, the two clamping blocks (27) are in a state of being detached from the annular preparation disk (9), and then the two first hydraulic telescopic rods (3) are synchronously contracted, drive the lifting bottom plate (5) to move up to the bottom of the reaction furnace (1), seal the bottom of the reaction furnace (1), and move the annular preparation disk (9) into the reaction furnace (1); S4, start the second hydraulic telescopic rod (18), drive the annular pressing plate (19) to press into the annular preparation disk (9) and then move upward to reset, so that the silicon powder in the annular preparation disk (9) is evenly spread on the annular pressing plate (19), and then start the first electric heater (14) and the two second electric heaters (16) to heat the temperature in the reaction furnace (1) to a specified temperature, and continuously inject nitrogen into the reaction furnace (1) through the gas injection pipe (20) to carry out a nitridation synthesis reaction; S5. After a certain period of nitriding synthesis reaction, the second hydraulic telescopic rod (18) is started to drive the annular pressure plate (19) to press into the annular preparation disk (9), to press the silicon carbide in the annular preparation disk (9), to squeeze out the excess gas inside, and then stop the heating work of the first electric heater (14) and the two second electric heaters (16), and then move the annular preparation disk (9) down out of the reaction furnace (1) through the first hydraulic telescopic rod (3), so that it moves between the two clamping blocks (27); S6, driving the threaded rod (23) to rotate in the opposite direction through the first motor (24), controlling the two moving rods (25) to move rightward, so that the clamping block (27) located on the left side contacts the annular preparation disk (9), and then starting the telescopic cylinder (31) to drive the clamping block (27) located on the right side to contact the annular preparation disk (9), completing the clamping work of the annular preparation disk (9), and then controlling the two first electric telescopic rods (13) to contract, so that the two movable round blocks (12) move downward out of the circular hole (11), and then controlling the two moving rods (25) to move leftward through the first motor (24), so that the annular preparation disk (9) is moved to the left side of the reaction furnace (1); S7, the rotating disk (30) is driven to rotate half a circle by the second motor (33), and then under the clamping action of the two clamping blocks (27), the annular preparation disk (9) rotates half the axis at the same time, so that its opening is set downward, and then the two push rods (37) can be driven to move downward by the second electric telescopic rod (36) and inserted into the corresponding circular holes (11), so that the silicon nitride block in the annular preparation disk (9) is pushed out of the annular preparation disk (9) by the downward movement of the two push rods (37), and the removal of the silicon nitride is completed; S8, cooling the taken out silicon nitride block, crushing it after cooling, and performing powder making work.

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