Device and method for measuring thermal conductivity of silicon carbide crucible

Abstract

The invention relates to the field of crucible thermal conductivity measurement, in particular to a device for measuring thermal conductivity of a silicon carbide crucible and a measuring method.The device comprises a heating furnace and a bottom support, the bottom support is fixedly arranged at the top of the crucible, the device further comprises a heat preservation shell and a clamping mechanism, and the heat preservation shell is composed of a bottom shell and a top cover; a top cover and a bottom shell are arranged in the bottom shell, a heating cavity for accommodating the crucible is formed between the top cover and the bottom shell, the clamping mechanism comprises a centering clamp and an adjusting assembly, and a thermocouple for monitoring the temperature of the crucible is arranged on the centering clamp. The clamping block is fixed through the positioning driver, the stability of the centering clamp is further enhanced, in the heating process, the clamping block and the thermocouple work cooperatively, data acquisition points are increased, and the measurement accuracy is improved.

Description

Technical Field

[0001] The invention relates to the field of crucible thermal conductivity measurement, and in particular to a device and a method for measuring the thermal conductivity of a silicon carbide crucible. Background Art

[0002] The thermal conductivity of silicon carbide crucible directly affects its performance during high-temperature processing, especially in processes such as melting, purification and single crystal growth. A good thermal conductivity is essential to ensure temperature uniformity in the crucible, improve production efficiency and product quality. Currently, in order to measure the thermal conductivity of silicon carbide crucibles, the thermal conductivity is calculated by heating the sample and analyzing the change in temperature over time. However, samples of different sizes and shapes may have different effects on the heat conduction path, resulting in the inability to accurately measure the thermal conductivity of the crucible.

[0003] The currently published Chinese patent application CN113109389A discloses a device and method for quickly measuring the thermal conductivity of a graphite silicon carbide crucible sample, comprising a constant temperature water tank, a thermocouple, a digital display device and a heating platform, wherein the constant temperature water tank comprises a water pipe, and a pipe valve is provided on the outer wall of the water pipe, and a clamping mechanism is provided on the top of the heating platform; a water cooling head is provided at one end of the water pipe, a ceramic substrate is fixedly connected to the inner wall of the clamping mechanism, a graphite silicon carbide crucible sample is clamped by the inner wall of the clamping mechanism through the ceramic substrate, thermal conductive silicone grease is provided on the bottom of the ceramic substrate, and one end of the electric coupling wire of the thermocouple and the digital display device is connected to the two sides of the ceramic substrate.

[0004] According to the above patent, the above patent clamps the crucible in the crucible through a clamping mechanism to prevent the crucible from shifting. However, the clamping mechanism cannot center the crucible in the center of the heating table, which easily leads to uneven heating, thereby causing inaccurate data of thermal conductivity measured by the thermocouple. Therefore, there is a need for a measuring device that can ensure that the crucible is heated evenly during the heating process, thereby ensuring accurate thermal conductivity measurement data. Summary of the invention

[0005] In view of the problems existing in the prior art, a device for measuring the thermal conductivity of a silicon carbide crucible is provided. The present invention ensures that the crucible always remains in a centered position in the heating furnace by adaptively adjusting the clamp block through an elastic connecting piece, and fixes the clamp block through a positioning driver, thereby further enhancing the stability of the centering fixture. During the heating process, the clamp block and the thermocouple work together to increase the data collection points and improve the measurement accuracy.

[0006] In order to solve the problems of the prior art, the present invention provides a device for measuring the thermal conductivity of a silicon carbide crucible, comprising a heating furnace for heating the crucible and a bottom support for supporting the crucible, the bottom support being fixedly arranged on the top of the crucible, and also comprising a heat-insulating shell and a clamping mechanism, the heat-insulating shell being composed of a bottom shell and a top cover, the bottom shell and the top cover being both cylindrical structures, the bottom shell being fixedly sleeved on the bottom support, the top cover being coaxially arranged above the bottom shell, and when the top cover is butted against the bottom shell, a heat-insulating shell is formed between the top cover and the bottom shell to accommodate the crucible therein The hot chamber, the clamping mechanism includes a centering clamp arranged on the bottom bracket and an adjusting component for adjusting the clamping position of the centering clamp according to the size of the crucible. When the crucible is placed on the bottom bracket and the clamping mechanism acts, the crucible is located at the center of the heating furnace, so that the crucible is heated evenly. The centering clamp is provided with a thermocouple for monitoring the temperature of the crucible. The thermocouple has a temperature sensing part and a lead part. When the centering clamp clamps the crucible through the action of the adjusting component, the temperature sensing part of the thermocouple is in a state of being in contact with the surface of the crucible.

[0007] Preferably, the centering clamp is composed of a plurality of clamping blocks, which are evenly distributed around the circumference of the bottom shell, and each clamping block can move on the bottom support along the axial direction of the bottom shell. The bottom support has a guide groove that slides with the lower end of the clamping block, and an adjustment component is provided on the bottom shell corresponding to each clamping block.

[0008] Preferably, the adjustment assembly includes a movable frame fixedly arranged on the clamping block, an elastic connecting piece movably arranged between the movable frame and the bottom shell, and a positioning driver arranged on the bottom shell and capable of fixing the movable frame. When the crucible is placed between all the clamping blocks, each clamping block is in a state of adaptively pressing the crucible under the action of the corresponding elastic connecting piece. When the crucible is fully supported on the bottom support and through the action of the positioning driver, the clamping block is in a fixed state, so that the crucible remains in a stable and centered state on the heating furnace.

[0009] Preferably, the upper end of each clamping block has a head extending outward, and the inner side of the head has an inclined surface for allowing the bottom of the crucible to slide in and be surrounded and fixed by all the clamping blocks.

[0010] Preferably, each clamp block is provided with a thermocouple, and a through hole is opened on the clamp block for the thermocouple to pass through. A buffer spring is fixedly connected between the temperature sensing part of the thermocouple and the clamp block. When the clamp block is pressed against the crucible, the temperature sensing part of the thermocouple is in a tightly fitted state with the surface of the crucible, and the buffer spring is in a compressed state at this time.

[0011] Preferably, a heat-insulating layer is provided inside the heat-insulating shell to prevent the external environment from affecting the heating effect of the crucible.

[0012] Preferably, a guide member for stabilizing the movable frame is provided on the bottom shell, the guide member has a pair of guide wheels for clamping the movable frame therein, an axis connecting plate for rotatably connecting the guide wheels is fixedly provided on the bottom shell, and the movable frame has a guide rail for slidingly cooperating with each guide wheel.

[0013] Preferably, an elastic connecting member is provided between the upper and lower ends of the movable frame and the bottom shell, and the elastic connecting member has a connecting rod and a compression spring. A guide rod is fixedly provided on the bottom shell for the compression spring to be sleeved thereon, and the axial direction of the guide rod is parallel to the axial direction of the bottom shell. A sliding sleeve is slidingly sleeved on the guide rod and fixedly connected to the compression spring. One end of the connecting rod is hinged to the sliding sleeve, and the other end is hinged to the movable frame.

[0014] Preferably, a positioning driver is provided on the upper and lower parts of the bottom shell, and the positioning driver has a fixed magnetic ring and a movable magnetic ring coaxial with the bottom shell, the fixed magnetic ring is fixedly connected to the guide rod corresponding to each movable frame, the movable magnetic ring is fixedly connected to the sliding sleeve corresponding to each movable frame, the movable magnetic ring is sleeved on the fixed magnetic ring, and the fixed magnetic ring and the movable magnetic ring are both electromagnetic rings.

[0015] The present invention also provides a method for measuring the thermal conductivity of a silicon carbide crucible, comprising the following steps: S1. Place the crucible to be measured on the bottom bracket, and use a centering fixture to accurately center the crucible and fix it on the bottom bracket; S2, start the heating furnace, set the appropriate heating temperature, and keep the crucible in the required high temperature environment; S3, making the temperature-sensing part of the thermocouple contact with the surface of the crucible through the centering fixture, and connecting the temperature control instrument to monitor the temperature; S4. Based on the recorded temperature data and the thermal properties of the crucible material, the thermal conductivity value of the crucible is measured.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention uses the centering fixture and the adjustment component to accurately fix the crucible on the base and ensure that it is in the center of the heating furnace, so that the crucible can receive heat evenly during the heating process without the occurrence of thermal gradient differences caused by offset, thereby affecting the measurement results. At the same time, the thermocouple can follow the centering fixture to clamp the crucible and contact the crucible, so that the temperature of the crucible can be monitored in real time without manual operation, which greatly improves the degree of automation of the measurement. With the accurate positioning of the crucible, the heating furnace is started and the appropriate temperature is set to ensure that the thermal conductivity of the crucible is measured in a high-temperature environment, thereby ensuring the accuracy of the thermal conductivity measurement.

[0017] 2. The present invention effectively ensures the stability and position accuracy of the crucible in the heating furnace through the interaction between the clamps and the crucible. When the crucible is placed between all the clamps, each clamp will adaptively apply appropriate pressure according to the action of its own elastic connector to ensure that the crucible remains in a centered position on the heating furnace. It can adapt to different sizes and shapes of crucibles. As the crucible is fully supported on the base, the positioning drive fixes the movable frame so that each clamp is in a fixed state, further enhancing the stability of the centering fixture, thereby achieving uniform temperature distribution during the heating process and improving the accuracy of the crucible thermal conductivity measurement.

[0018] 3. The present invention improves the temperature monitoring accuracy and stability during the experiment through the synergistic effect of the clamp and the thermocouple. Since each clamp is provided with a thermocouple, the crucible can be monitored at multiple points in real time, which not only increases the number of data collection points, but also effectively improves the measurement accuracy. After the clamp is pressed against the crucible, the thermocouple is pressed with appropriate pressure under the action of the buffer spring, ensuring close contact between the temperature sensing part of the thermocouple and the surface of the crucible, avoiding poor contact or measurement errors caused by thermal expansion or temperature fluctuations, and further improving the accuracy of the measurement of the thermal conductivity of the crucible. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 The present invention is a schematic diagram of the three-dimensional structure of the top surface orientation of a device for measuring the thermal conductivity of a silicon carbide crucible.

[0020] Figure 2 The present invention is a schematic diagram of the three-dimensional structure of the bottom surface orientation of a device for measuring the thermal conductivity of a silicon carbide crucible.

[0021] Figure 3 The schematic diagram of the three-dimensional structure of a device for measuring the thermal conductivity of a silicon carbide crucible is shown.

[0022] Figure 4 A partial plan cross-sectional view of a device for measuring the thermal conductivity of a silicon carbide crucible.

[0023] Figure 5 The present invention is a partial three-dimensional structural cross-sectional view of a device for measuring the thermal conductivity of a silicon carbide crucible.

[0024] Figure 6 The present invention is a schematic diagram of the three-dimensional structure of a crucible and a heating furnace of a device for measuring the thermal conductivity of a silicon carbide crucible.

[0025] Figure 7 The present invention is a three-dimensional structural schematic diagram of a clamping block and an adjustment assembly of a device for measuring the thermal conductivity of a silicon carbide crucible.

[0026] Figure 8A plan cross-sectional view of a clamping block and an adjustment assembly of an apparatus for measuring thermal conductivity of a silicon carbide crucible is provided.

[0027] Fig. 9 yes Figure 4 An enlarged schematic diagram of point A.

[0028] Fig.10 yes Figure 4 An enlarged schematic diagram of point B.

[0029] Fig.11 yes Figure 4 Enlarged schematic diagram of point C.

[0030] The numbers in the figure are: 1. crucible; 2. heating furnace; 3. bottom support; 4. insulation shell; 41. bottom shell; 42. top cover; 43. insulation layer; 5. centering fixture; 51. clamping block; 511. head; 5111. inclined surface; 6. adjustment assembly; 61. movable frame; 611. guide wheel; 6111. shaft connecting plate; 612. guide rail; 62. elastic connector; 621. connecting rod; 622. compression spring; 6221. guide rod; 6222. sleeve; 63. positioning driver; 631. fixed magnetic ring; 632. movable magnetic ring; 7. thermocouple; 71. temperature sensing part; 711. buffer spring; 72. lead part. DETAILED DESCRIPTION

[0031] In order to further understand the features, technical means, specific objectives and functions of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0032] See also Figure 1-Figure 5 As shown, a device for measuring the thermal conductivity of a silicon carbide crucible comprises a heating furnace 2 for heating a crucible 1 and a bottom support 3 for supporting the crucible 1, wherein the bottom support 3 is fixedly arranged on the top of the crucible 1, and further comprises a heat-insulating shell 4 and a clamping mechanism, wherein the heat-insulating shell 4 is composed of a bottom shell 41 and a top cover 42, wherein both the bottom shell 41 and the top cover 42 are cylindrical structures, wherein the bottom shell 41 is fixedly sleeved on the bottom support 3, and the top cover 42 is coaxially arranged above the bottom shell 41, and when the top cover 42 is butted against the bottom shell 41, a heating chamber for accommodating the crucible 1 is formed between the top cover 42 and the bottom shell 41 The clamping mechanism includes a centering clamp 5 arranged on the bottom bracket 3 and an adjusting component 6 for adjusting the clamping position of the centering clamp 5 according to the size of the crucible 1. When the crucible 1 is placed on the bottom bracket 3 and the crucible 1 is located at the center of the heating furnace 2 through the action of the clamping mechanism, the crucible 1 is evenly heated. The centering clamp 5 is provided with a thermocouple 7 for monitoring the temperature of the crucible 1. The thermocouple 7 has a temperature sensing portion 71 and a lead portion 72. When the centering clamp 5 clamps the crucible 1 through the action of the adjusting component 6, the temperature sensing portion 71 of the thermocouple 7 is in a state of being in contact with the surface of the crucible 1.

[0033] When measuring the thermal conductivity of the silicon carbide crucible 1, the silicon carbide crucible 1 to be measured is placed on the bottom support 3. In this process, the crucible 1 is placed in the centering fixture 5. Under the action of the adjustment component 6, the centering fixture 5 is adjusted to clamp the crucible 1 so that the crucible 1 is centered and stably fixed on the bottom support 3, so that the crucible 1 is accurately located in the center of the heating furnace 2. Ensure that the heat distribution during the heating process is uniform to avoid the influence of thermal gradient on the measurement results. Then, the top cover 42 is pressed down onto the bottom shell 41 by the cylinder, and the cylinder is not shown in the figure, so that the crucible 1 is accommodated in the formed heating chamber to avoid the crucible 1 being affected by the flow of external air during the heating process. Then, the heating furnace 2 is started and the heating temperature is set according to the experimental requirements. Ensure that the crucible 1 can be in a high temperature state, thereby promoting the effectiveness of the thermal conductivity measurement. After the crucible 1 is clamped by the centering fixture 5, since the thermocouple 7 is installed on the centering fixture 5, the thermocouple 7 is synchronously in contact with the crucible 1 without manual operation. The temperature of the surface of the crucible 1 is monitored in real time by the thermocouple 7, and the lead 72 of the thermocouple 7 is connected to an external temperature control instrument, which is not shown in the figure. The temperature control instrument can display the real-time temperature data of the crucible 1, and the temperature change curve is observed at this time to calculate the data of thermal conductivity. By recording the temperature data in the experiment and combining the material properties of the crucible 1, the specific value of thermal conductivity is finally calculated. After completing the experiment, turn off the heating furnace 2 and let the crucible 1 cool naturally.

[0034] See also Figure 4-Figure 8 As shown, the centering clamp 5 is composed of a plurality of clamping blocks 51, and the plurality of clamping blocks 51 are evenly distributed in the circumferential direction around the bottom shell 41, and each clamping block 51 can move on the bottom support 3 along the axial direction of the bottom shell 41, and the bottom support 3 has a guide groove that slides with the lower end of the clamping block 51, and an adjustment component 6 is provided on the bottom shell 41 corresponding to each clamping block 51.

[0035] When the crucible 1 is placed, the crucible 1 is gradually wrapped by all the clamps 51, and the clamps 51 fine-tune their positions through the adjustment assembly 6 to ensure that the crucible 1 is in the center of the heating furnace 2 and is evenly clamped by all the clamps 51. In this process, the lower end of the clamp 51 can move smoothly on the bottom bracket 3 through sliding cooperation with the guide groove, ensuring that the clamp 51 can be adaptively adjusted according to the shape and size of the crucible 1, so that the crucible 1 is firmly fixed in the correct position. The crucible 1 will not be displaced due to external force or vibration, ensuring the position stability during the heating process and the accuracy of the experiment.

[0036] See also Figure 4-Figure 8As shown, the adjustment assembly 6 includes a movable frame 61 fixedly arranged on the clamping block 51, an elastic connecting member 62 movably arranged between the movable frame 61 and the bottom shell 41, and a positioning driver 63 arranged on the bottom shell 41 and capable of fixing the movable frame 61. When the crucible 1 is placed between all the clamping blocks 51, each clamping block 51 is in a state of adaptively pressing the crucible 1 under the action of the corresponding elastic connecting member 62, and when the crucible 1 is fully supported on the bottom support 3 and through the action of the positioning driver 63, the clamping block 51 is in a fixed state, so that the crucible 1 remains in a stable and centered state on the heating furnace 2.

[0037] When the crucible 1 is placed between all the clamps 51, each clamp 51 will adaptively apply pressure to the crucible 1 under the action of the corresponding elastic connector 62 to ensure that the crucible 1 is firmly placed on the base 3. The clamp 51 maintains appropriate pressure on the crucible 1 through the elastic action of the elastic connector 62, so that the crucible 1 can be evenly supported. As the crucible 1 is fully supported on the base 3, the positioning driver 63 begins to work, fixing the position of the movable frame 61 to ensure that each clamp 51 is firmly fixed. Finally, the clamp 51 is in a fixed state, ensuring that the crucible 1 always maintains a stable central position in the heating furnace 2 without deviation or shaking, thereby ensuring uniform temperature distribution during the heating process and improving the accuracy and reliability of the experiment.

[0038] See also Figure 6-Figure 9 As shown, the upper end of each clamping block 51 has a head 511 extending outward, and the inner side of the head 511 has an inclined surface 5111 for the bottom of the crucible 1 to slide into and be surrounded and fixed by all the clamping blocks 51 .

[0039] When the crucible 1 is placed between all the clamps 51, the inclined surface 5111 of the upper head 511 of each clamp 51 can guide the bottom of the crucible 1 to slide in smoothly, thereby preventing the crucible 1 from getting stuck or tilted. As the crucible 1 completely slides into the clamps 51, all the clamps 51 will adjust their positions adaptively and use their elastic connectors 62 to tightly surround the crucible 1, ensuring that the crucible 1 is firmly fixed in all the clamps 51.

[0040] See also Figure 4 , Figure 5 , Figure 8 and Fig.10 As shown, each clamp block 51 is provided with a thermocouple 7, and a through hole is opened on the clamp block 51 for the thermocouple 7 to pass through. A buffer spring 711 is fixedly connected between the temperature sensing part 71 of the thermocouple 7 and the clamp block 51. When the clamp block 51 presses against the crucible 1, the temperature sensing part 71 of the thermocouple 7 is in a tightly fitted state with the surface of the crucible 1, and the buffer spring 711 is in a compressed state.

[0041] When the clamp 51 presses against the crucible 1 and fixes its position firmly, the temperature sensing part 71 of the thermocouple 7 on each clamp 51 will fit closely to the surface of the crucible 1, thereby realizing accurate monitoring of the temperature of the crucible 1. Since each clamp 51 is provided with a thermocouple 7, the crucible 1 can be monitored at multiple points, thereby improving the accuracy of the measurement of the thermal conductivity of the crucible 1. When the clamp 51 presses against the crucible 1, due to the force of the buffer spring 711, it is ensured that the temperature sensing part 71 can be in close contact with the surface of the crucible 1. At this time, the buffer spring 711 is in a compressed state, applying appropriate pressure to the thermocouple 7, avoiding poor contact caused by thermal expansion or temperature change. The temperature change of the crucible 1 is monitored in real time and accurately to ensure the stability and reliability of the temperature measurement. Finally, the synergistic effect of the clamp 51 and the thermocouple 7 effectively improves the temperature control accuracy during the heating process, making the experimental results more reliable.

[0042] See also Figure 4 and Figure 5 As shown, a heat-insulating layer 43 is provided inside the heat-insulating shell 4 to prevent the external environment from affecting the heating effect of the crucible 1 .

[0043] When the crucible 1 is placed inside the heat-insulating shell 4, a heat-insulating layer 43 is provided inside the heat-insulating shell 4, which effectively prevents the influence of the external environment on the heating effect of the crucible 1. It prevents heat loss and ensures that the crucible 1 can be heated evenly and stably. It not only improves the thermal efficiency of the crucible 1 during heating, but also reduces the interference of external air flow, temperature change or other environmental factors on the experimental results, thereby ensuring the stability of the temperature inside the crucible 1 during heating and improving the accuracy of the measurement of the thermal conductivity of the crucible 1.

[0044] See also Figure 4 , Figure 5 and Figure 8 As shown, a guide member for stabilizing the movable frame 61 is provided on the bottom shell 41, and the guide member has a pair of guide wheels 611 for clamping the movable frame 61 therein, and an axis connecting plate 6111 for rotatably connecting the guide wheels 611 is fixedly provided on the bottom shell 41, and the movable frame 61 has a guide rail 612 for slidingly cooperating with each guide wheel 611.

[0045] When the movable frame 61 moves, since the movable frame 61 is provided with a guide rail 612 that slidably cooperates with the guide wheel 611, the movable frame 61 can slide stably on the guide rail 612. This makes the movable frame 61 move more stably, and can prevent the movable frame 61 from tilting or deflecting, thereby ensuring the stability of the clamping blocks 51. The crucible 1 is firmly clamped between all the clamping blocks 51, thereby improving the stability of the crucible 1 during the heating process.

[0046] See also Figure 4 , Figure 5 , Figure 7and Figure 8 As shown, an elastic connecting member 62 is provided between the upper and lower ends of the movable frame 61 and the bottom shell 41, and the elastic connecting member 62 has a connecting rod 621 and a compression spring 622. A guide rod 6221 is fixedly provided on the bottom shell 41 for the compression spring 622 to be sleeved thereon, and the axial direction of the guide rod 6221 is parallel to the axial direction of the bottom shell 41. A sliding sleeve 6222 fixedly connected to the compression spring 622 is slidably sleeved on the guide rod 6221. One end of the connecting rod 621 is hinged to the sliding sleeve 6222, and the other end is hinged to the movable frame 61.

[0047] When the crucible 1 is placed between all the clamps 51, the movable frame 61 will be pushed outward due to the external force. At this time, the elastic connectors 62 at the upper and lower ends of the movable frame 61 come into play. Since the elastic connector 62 is composed of a compression spring 622 and a connecting rod 621, when the movable frame 61 is pushed, the connecting rod 621 drives the sliding sleeve 6222 to move on the guide rod 6221, so that the sliding sleeve 6222 is pulled toward the direction close to the movable frame 61. At this time, the compression spring 622 begins to be compressed and still exerts pressure on the clamps 51, so that all the clamps 51 are adaptively pressed against the surface of the crucible 1 to ensure that the crucible 1 is centered in the center of the heating furnace 2.

[0048] See also Figure 4 , Figure 5 , Figure 7 , Figure 8 and Fig.11 As shown, a positioning driver 63 is provided at the upper and lower parts of the bottom shell 41, and the positioning driver 63 has a fixed magnetic ring 631 and a movable magnetic ring 632 coaxial with the bottom shell 41, the fixed magnetic ring 631 is fixedly connected to the guide rod 6221 corresponding to each movable frame 61, the movable magnetic ring 632 is fixedly connected to the sliding sleeve 6222 corresponding to each movable frame 61, the movable magnetic ring 632 is sleeved on the fixed magnetic ring 631, and the fixed magnetic ring 631 and the movable magnetic ring 632 are both electromagnetic rings.

[0049] When the positioning driver 63 starts to work, the fixed magnetic ring 631 and the movable magnetic ring 632 at the upper and lower parts of the bottom shell 41 respectively generate magnetic fields through current control. By adjusting the current, the magnetic force between the fixed magnetic ring 631 and the movable magnetic ring 632 attracts each other, thereby fixing the movable magnetic ring 632. At this time, all the sliding sleeves 6222 are fixed, and the movable frame 61 is indirectly fixed through the connecting rod 621. Since the movable frame 61 is fixedly connected to the clamping block 51, the position of the clamping block 51 is fixed, ensuring that the clamping block 51 is always in the clamping position after adaptation during the entire working process, providing high-precision positioning control of the crucible 1.

[0050] A method for measuring a device for measuring the thermal conductivity of a silicon carbide crucible, applied to a device for measuring the thermal conductivity of a silicon carbide crucible, comprises the following steps: S1, placing the crucible 1 to be measured on the bottom support 3, and using the centering fixture 5 to accurately center the crucible 1 and fix it on the bottom support 3; S2, start the heating furnace 2, set the appropriate heating temperature, so that the crucible 1 is in the required high temperature environment; S3, making the temperature sensing part 71 of the thermocouple 7 contact with the surface of the crucible 1 through the centering fixture 5, and connecting a temperature control instrument to monitor the temperature; S4. According to the recorded temperature data and in combination with the thermal characteristics of the crucible 1 material, the thermal conductivity value of the crucible 1 is measured.

[0051] The present invention ensures that the crucible 1 always maintains a centered position in the heating furnace 2 through the interaction between the clamp block 51 and the crucible 1 and the adaptive adjustment of the elastic connector 62, and is adaptable to crucibles 1 of different sizes and shapes. As the crucible 1 is fully supported on the base 3, the positioning driver 63 fixes the movable frame 61 to fix the clamp block 51, thereby further enhancing the stability of the centering fixture 5. During the heating process, the clamp block 51 and the thermocouple 7 work together to achieve multi-point real-time temperature monitoring of the crucible 1, increase the data collection points, and improve the measurement accuracy. The thermocouple 7 on each clamp block 51 applies appropriate pressure under the action of the spring to ensure that the temperature sensing portion 71 of the thermocouple 7 is in close contact with the surface of the crucible 1, avoid poor contact caused by temperature fluctuations or thermal expansion, and further improve the accuracy of thermal conductivity measurement.

[0052] The above embodiments only express one or several implementation modes of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the protection scope of the present invention. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the attached claims.

Claims

1. A device for measuring the thermal conductivity of a silicon carbide crucible, comprising a heating furnace (2) for heating the crucible (1) and a base (3) for supporting the crucible (1), wherein the base (3) is fixedly arranged on the top of the crucible (1); It is characterized in that It also includes a heat-insulating shell (4) and a clamping mechanism; The heat-insulating shell (4) is composed of a bottom shell (41) and a top cover (42); the bottom shell (41) and the top cover (42) are both cylindrical structures; the bottom shell (41) is fixedly sleeved on the bottom support (3); the top cover (42) is coaxially arranged above the bottom shell (41); when the top cover (42) and the bottom shell (41) are butt-jointed, a heating chamber for accommodating the crucible (1) is formed between the top cover (42) and the bottom shell (41); The clamping mechanism comprises a centering clamp (5) arranged on a base (3) and an adjustment component (6) for adjusting the clamping position of the centering clamp (5) according to the size of the crucible (1); when the crucible (1) is placed on the base (3) and the clamping mechanism acts, the crucible (1) is located at the center of the heating furnace (2), so that the crucible (1) is evenly heated; A thermocouple (7) for monitoring the temperature of the crucible (1) is provided on the centering fixture (5). The thermocouple (7) comprises a temperature sensing portion (71) and a lead portion (72). When the centering fixture (5) clamps the crucible (1) through the action of the adjustment component (6), the temperature sensing portion (71) of the thermocouple (7) is in contact with the surface of the crucible (1).

2. The device for measuring thermal conductivity of a silicon carbide crucible according to claim 1, characterized in that: The centering clamp (5) is composed of a plurality of clamping blocks (51), which are evenly distributed in the circumferential direction around the bottom shell (41), and each clamping block (51) can move on the bottom bracket (3) along the axis direction of the bottom shell (41). The bottom bracket (3) has a guide groove that is slidably matched with the lower end of the clamping block (51), and the bottom shell (41) is provided with an adjustment component (6) corresponding to each clamping block (51).

3. The device for measuring thermal conductivity of a silicon carbide crucible according to claim 2, characterized in that: The adjustment component (6) comprises: A movable frame (61) fixedly mounted on the clamping block (51); an elastic connecting member (62) movably arranged between the movable frame (61) and the bottom shell (41); and a positioning driver (63) arranged on the bottom shell (41) and capable of fixing the movable frame (61); When the crucible (1) is placed between all the clamping blocks (51), each clamping block (51) is in a state of adaptively pressing the crucible (1) under the action of the corresponding elastic connecting member (62), and when the crucible (1) is fully supported on the base (3) and the positioning driver (63) is activated, the clamping blocks (51) are in a fixed state, so that the crucible (1) remains in a stable and centered state on the heating furnace (2).

4. The device for measuring thermal conductivity of a silicon carbide crucible according to claim 2, characterized in that: The upper end of each clamping block (51) has a head (511) extending outwards, and the inner side of the head (511) has an inclined surface (5111) that allows the bottom of the crucible (1) to slide in and be surrounded and fixed by all the clamping blocks (51).

5. The device for measuring thermal conductivity of a silicon carbide crucible according to claim 1, characterized in that: Each clamping block (51) is provided with a thermocouple (7), and a through hole is provided on the clamping block (51) for the thermocouple (7) to pass through. A buffer spring (711) is fixedly connected between the temperature sensing portion (71) of the thermocouple (7) and the clamping block (51). When the clamping block (51) is pressed against the crucible (1), the temperature sensing portion (71) of the thermocouple (7) and the surface of the crucible (1) are in a tightly fitted state, and the buffer spring (711) is in a compressed state.

6. The device for measuring thermal conductivity of a silicon carbide crucible according to claim 1, characterized in that: A heat-insulating layer (43) is provided inside the heat-insulating shell (4) to prevent the external environment from affecting the heating effect of the crucible (1).

7. The device for measuring thermal conductivity of a silicon carbide crucible according to claim 3, characterized in that: A guide member for stabilizing the movable frame (61) is provided on the bottom shell (41), the guide member having a pair of guide wheels (611) for clamping the movable frame (61) therein, a shaft connecting plate (6111) for rotatably connecting the guide wheels (611) is fixedly provided on the bottom shell (41), and the movable frame (61) has a guide rail (612) for slidingly cooperating with each guide wheel (611).

8. The device for measuring thermal conductivity of a silicon carbide crucible according to claim 3, characterized in that: An elastic connecting member (62) is provided between the upper and lower ends of the movable frame (61) and the bottom shell (41). The elastic connecting member (62) comprises a connecting rod (621) and a compression spring (622). A guide rod (6221) is fixedly provided on the bottom shell (41) for the compression spring (622) to be sleeved thereon. The axial direction of the guide rod (6221) is parallel to the axial direction of the bottom shell (41). A sliding sleeve (6222) is slidably sleeved on the guide rod (6221) and is fixedly connected to the compression spring (622). One end of the connecting rod (621) is hinged to the sliding sleeve (6222), and the other end is hinged to the movable frame (61).

9. The device for measuring thermal conductivity of a silicon carbide crucible according to claim 8, characterized in that: A positioning driver (63) is provided at the upper and lower parts of the bottom shell (41). The positioning driver (63) comprises a fixed magnetic ring (631) and a movable magnetic ring (632) coaxial with the bottom shell (41). The fixed magnetic ring (631) is fixedly connected to a guide rod (6221) corresponding to each movable frame (61). The movable magnetic ring (632) is fixedly connected to a sliding sleeve (6222) corresponding to each movable frame (61). The movable magnetic ring (632) is sleeved on the fixed magnetic ring (631). Both the fixed magnetic ring (631) and the movable magnetic ring (632) are electromagnetic rings.

10. A method for measuring the thermal conductivity of a silicon carbide crucible, applied to the device for measuring the thermal conductivity of a silicon carbide crucible as claimed in any one of claims 1 to 9, characterized in that: The following steps are involved: S1. placing the crucible (1) to be measured on the base (3), and using a centering fixture (5) to accurately center the crucible (1) and fix it on the base (3); S2, starting the heating furnace (2), setting an appropriate heating temperature, so that the crucible (1) is in a desired high temperature environment; S3, using a centering fixture (5) to make the temperature sensing portion (71) of the thermocouple (7) contact the surface of the crucible (1), and connecting a temperature control instrument to monitor the temperature; S4. Based on the recorded temperature data and in combination with the thermal properties of the crucible (1) material, the thermal conductivity value of the crucible (1) is measured.

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