Miniature tube furnace capable of being observed in real time

Abstract

The present invention relates to the technical field of material performance testing, and discloses a real-time observable miniature tubular furnace, which comprises: a housing, the middle of which defines a mounting chamber and the bottom of which is provided with an exhaust pipe; one end of each air inlet pipe is communicated with the mounting hole, and the other end of each air inlet pipe penetrates through the top plate in the horizontal direction and extends to the outside; the quartz tube is vertically arranged in the mounting cavity, and the corundum table is arranged in the quartz tube; the observation light window is embedded in the inner surface of the mounting hole and is positioned above the calcined sample. According to the invention, gas can be introduced from multiple directions and is uniformly distributed in the furnace body, so that local temperature fluctuation of a sample is avoided; in the sintering process, the microstructure change of the sintered sample can be captured in real time through the observation light window; and the high-temperature ceramic heating wafer and the high-temperature ceramic heating arc-shaped piece can enable heat to be more uniformly transferred to the sintered sample, so that local overheating of the sintered sample is avoided, the stability and the uniformity of temperature rise of the sample are guaranteed, and the quality of a sintered product is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of material performance testing, in particular to a micro tube furnace capable of real-time observation. Background Art

[0002] Tube furnaces are common experimental equipment used in a wide range of fields, including material synthesis, crystal growth, and heat treatment. However, traditional tube furnaces often have limitations, such as large size, low heating efficiency, slow heating rates, and the inability to observe the sintering process in real time. This, to a certain extent, limits researchers' in-depth understanding and precise control of experimental processes.

[0003] To overcome these shortcomings, patent CN110068535A discloses a high-temperature tube furnace suitable for in-situ optical microscopy and spectral analysis. This furnace, equipped with an observation port, can be coupled with an optical microscopy system and a spectral measurement and analysis system, enabling real-time, in-situ morphological observation and spectral measurement of the sample during sintering. However, the tube furnace's bulk and slow heating rate remain unresolved. Furthermore, the airflow flowing from one side leads to uneven temperature distribution during material synthesis and crystal growth, affecting sintering quality.

[0004] In view of this, how to provide a tubular furnace with a small size, high heating efficiency and the ability to observe the sintering process in real time is an urgent problem that needs to be solved by those skilled in the art. Summary of the Invention

[0005] The purpose of the present invention is to provide a micro tube furnace capable of real-time observation to solve the problems existing in the prior art.

[0006] To achieve the above object, the present invention provides a micro tube furnace capable of real-time observation, comprising:

[0007] The housing defines a mounting chamber in its center and an exhaust pipe communicating with the mounting chamber is provided at its bottom;

[0008] A top plate is provided on the housing, and the top plate has mounting holes formed on its upper and lower surfaces corresponding to the upper opening of the mounting chamber, and the mounting holes are connected to the upper opening;

[0009] a plurality of air inlet pipes, one end of which is connected to the mounting hole and the other end of which passes through the top plate in a horizontal direction and extends to the outside;

[0010] A quartz tube is vertically arranged in the installation chamber;

[0011] a corundum table, arranged inside the quartz tube and close to the upper end of the quartz tube, and used for placing the calcined sample;

[0012] An observation light window is embedded in the inner surface of the mounting hole, and the observation light window is located above the calcined sample.

[0013] Furthermore, a high-temperature ceramic heating disc is provided at the bottom of the installation chamber, and a high-temperature ceramic heating arc sheet is provided on the inner wall of the installation chamber; the high-temperature ceramic heating disc is provided with a first through hole corresponding to the exhaust pipe.

[0014] Furthermore, four air intake pipes are provided, and the four air intake pipes are evenly spaced along the circumference of the top plate.

[0015] Furthermore, a corundum base plate is provided on the high-temperature ceramic heating disc, and a second through hole is opened on the corundum base plate corresponding to the exhaust pipe. A guide groove is opened on the upper surface of the corundum base plate, and the guide groove can guide the gas into the second through hole and discharge it through the first through hole and the exhaust pipe.

[0016] Furthermore, a threaded steel ring is provided on the upper edge of the quartz tube, and the threaded steel ring is threadedly connected to the inner wall of the installation chamber.

[0017] Furthermore, a sealing ring is provided between the threaded steel ring and the upper edge of the quartz tube.

[0018] Furthermore, it also includes: a side plate, the installation chamber is U-shaped and has a side opening, and the side plate is covered and arranged at the side opening of the installation chamber.

[0019] Furthermore, it also includes:

[0020] a temperature sensor embedded in the side panel, comprising a temperature probe and a temperature signal output line, wherein the temperature probe is located in the installation chamber and the temperature signal output line is located outside the side panel;

[0021] The pressure sensor is embedded in the side plate and has a pressure probe and a pressure signal output line. The pressure sensor is located in the installation chamber, and the pressure signal output line is located outside the side plate.

[0022] Furthermore, the top plate and the outer shell are connected via longitudinal screws, and the outer shell and the side plates are connected via transverse screws.

[0023] Furthermore, the observation light window is made of quartz glass.

[0024] The present invention discloses the following technical effects:

[0025] 1. The top plate is equipped with multiple air inlet pipes, and the bottom of the outer shell is equipped with exhaust pipes, allowing gas to enter from multiple directions and evenly distribute it within the furnace. When the gas enters the furnace, it does not directly contact the calcined sample. It flows from top to bottom toward the sample through the mounting holes of the top plate, avoiding local temperature fluctuations in the sample, ensuring the stability and uniformity of the sample heating, and improving the quality of the sintered product. During the sintering process, the microscopic morphological changes of the sintered sample can be captured in real time through the observation window.

[0026] 2. A high-temperature ceramic heating disc is provided at the bottom of the installation chamber, and a high-temperature ceramic heating arc is provided on the inner wall of the installation chamber. The two can form a surround heating structure, so that heat is transferred to the sintered sample more evenly, avoiding local overheating of the sintered sample, and further improving the stability and uniformity of the sample heating.

[0027] 3. A corundum base plate is placed on the high-temperature ceramic heating disc. Its upper surface features diversion grooves, allowing exhaust gases to be smoothly discharged from the exhaust pipe while also reducing heat loss. This not only improves heating efficiency and reduces energy loss, but also ensures a uniform temperature distribution within the furnace, thereby enhancing sample sintering quality.

[0028] 4. The overall structure of the equipment is compact and small in size. It can be assembled with an external optical microscope and Raman spectroscopy system, and can capture the microscopic morphological changes of samples in the furnace in real time, such as sample color, micromorphology, and phase change. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0030] Figure 1 It is a schematic diagram of the mechanism of the present invention;

[0031] Figure 2 It is a cross-sectional schematic diagram of the present invention;

[0032] Figure 3 This is a schematic diagram of the cross section of the corundum platform;

[0033] Figure 4 Schematic diagram of the shell structure;

[0034] Figure 5 This is an optical microscopic observation picture;

[0035] Figure 6 is the Raman spectrum analysis diagram;

[0036] Among them, 1. Shell; 2. Exhaust pipe; 3. Top plate; 4. Inlet pipe; 5. Quartz tube; 6. Corundum table; 7. Observation light window; 8. High-temperature ceramic heating disc; 9. High-temperature ceramic heating arc plate; 10. Corundum bottom plate; 11. Threaded steel ring; 12. Sealing ring; 13. Side plate; 14. Temperature sensor; 15. Pressure sensor; 16. Longitudinal screw; 17. Horizontal screw; 18. Power cord. DETAILED DESCRIPTION

[0037] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0038] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0039] An embodiment of the present invention provides a micro tube furnace capable of real-time observation, comprising:

[0040] The housing 1 defines a mounting chamber in the middle thereof and an exhaust pipe 2 communicating with the mounting chamber is provided at the bottom thereof;

[0041] The top plate 3 is covered on the housing 1, and the top plate 3 has mounting holes formed on the upper and lower surfaces corresponding to the upper opening of the mounting chamber, and the mounting holes are connected to the upper opening;

[0042] A plurality of air inlet pipes 4, one end of which is connected to the mounting hole, and the other end of which passes through the top plate 3 in a horizontal direction and extends to the outside;

[0043] The quartz tube 5 is vertically arranged in the installation chamber;

[0044] A corundum table 6 is provided inside the quartz tube 5 and close to the upper end of the quartz tube 5. The corundum table 6 is used to place the calcined sample;

[0045] The observation light window 7 is embedded in the inner surface of the mounting hole, and the observation light window 7 is located above the calcined sample.

[0046] In this embodiment, a high-temperature ceramic heating disc 8 is installed at the bottom of the mounting chamber, and a high-temperature ceramic heating arc 9 is installed on the inner sidewall of the mounting chamber. A first through-hole is formed in the high-temperature ceramic heating disc 8 corresponding to the exhaust pipe 2. The high-temperature ceramic heating disc 8 and the high-temperature ceramic heating arc 9 are made of a highly conductive, high-temperature resistant ceramic material (doped with silicon carbide fiber). They have excellent thermal shock resistance and high-temperature stability, and can maintain stable heating performance during long-term high-temperature operation.

[0047] In this embodiment, the high temperature ceramic heating disc 8 and the high temperature ceramic heating arc piece 9 are powered by a power line 18 , one end of the power line 18 is connected to the two heating mechanisms, and the other end passes through the housing 1 and is connected to the power supply.

[0048] In this embodiment, four air inlet pipes 4 are provided, and the four air inlet pipes 4 are evenly spaced along the circumference of the top plate 3 .

[0049] In this embodiment, a corundum base plate 10 is mounted on the high-temperature ceramic heating disc 8. This base plate 10 has a second through-hole corresponding to the exhaust pipe 2. A guide groove is formed on the upper surface of the base plate 10, directing gas into the second through-hole and out through the first through-hole and the exhaust pipe 2. The corundum table 6 maintains stability and uniform heating of the sintered sample within the furnace. The base plate 10 is removable for easy cleaning and replacement.

[0050] In this embodiment, a threaded steel ring 11 is provided on the upper edge of the quartz tube 5. The threaded steel ring 11 is threadedly connected to the inner wall of the installation chamber. The installation position of the quartz tube 5 can be adjusted by adjusting the connection position of the threaded steel ring 11 with the inner wall of the installation chamber, thereby maintaining the airtightness of the entire device.

[0051] In this embodiment, a sealing ring 12 is provided between the threaded steel ring 11 and the upper edge of the quartz tube 5 .

[0052] In this embodiment, the side panel 13 is further included. The installation chamber is U-shaped and has a side opening. The side panel 13 is arranged to cover the side opening of the installation chamber.

[0053] In this embodiment, it also includes:

[0054] The temperature sensor 14 is embedded in the side panel 13 and has a temperature probe and a temperature signal output line. The temperature probe is located in the installation chamber, and the temperature signal output line is located outside the side panel 13.

[0055] The pressure sensor 15 is embedded in the side plate 13 and has a pressure probe and a pressure signal output line. The pressure sensor 15 is located in the installation chamber, and the pressure signal output line is located outside the side plate 13 .

[0056] In this embodiment, the top plate 3 is connected to the outer shell 1 via longitudinal screws 16, and the outer shell 1 is connected to the side panels 13 via transverse screws 17. High-temperature-resistant rubber gaskets are installed between the top plate 3 and the outer shell 1, and between the outer shell 1 and the side panels 13, to ensure the device's sealing performance. The outer shell 1 is made of high-strength, high-temperature-resistant stainless steel. The top plate 3, side panels 13, and the outer shell 1 are all provided with a thermal insulation layer. This thermal insulation layer is wrapped with multiple layers of ceramic fiber material, effectively reducing the temperature of the outer shell 1 and providing excellent thermal insulation performance.

[0057] In this embodiment, the observation window 7 is made of high-transmittance, high-temperature-resistant quartz glass, ensuring excellent optical performance even in high-temperature environments. Due to its compact size, the device can be integrated with an external optical microscope and Raman spectroscopy system, enabling real-time capture of microscopic morphological changes within the furnace, such as sample color, micromorphology, and phase transitions.

[0058] The copper hydroxide sample was evenly placed on the corundum table 6. The quartz tube 5 was secured to the furnace body via a threaded steel ring 11 to ensure airtightness. Argon gas was introduced into the tubular furnace through the gas inlet pipe 4 to maintain a stable atmosphere. The furnace temperature was raised to 200°C, 300°C, 400°C, 500°C, 550°C, and 600°C using a high-temperature ceramic heating disc 8 and a high-temperature ceramic heating arc 9. Each temperature was maintained for a specified period of time to ensure sufficient annealing of the sample. An optical microscope connected to the observation window 7 was used to observe the micromorphological changes of the sample at different temperatures in real time, and the observation results were recorded. In the unannealed (original) state, the sample surface was light blue. At 200°C, the sample surface color changed to brown. At 300°C, the sample surface color changed to black. At 400°C, the sample surface color changed to dark red. At 500°C, the sample surface color changed to orange. At 550°C, the sample surface color changed to red. At 600°C, the sample surface color changed to purple-red. Through optical microscopy, it can be clearly seen that the surface color of the copper hydroxide sample changes at different annealing temperatures, which indicates that the sample undergoes different phase transitions at different temperatures.

[0059] In the above process, when the furnace temperature rises to 200℃, the characteristic peaks of CuO appear in the Raman spectrum, which are 290cm -1 、341cm -1 and 630cm -1 , indicating that copper hydroxide has been completely dehydrated and converted into CuO at 200℃. When the furnace temperature rises to 300℃, the characteristic peak of Cu2O in the Raman spectrum (147cm -1 、218cm -1 、412cm -1 and 625cm -1) becomes obvious and dominant, while the characteristic peak of CuO weakens, indicating that the sample has undergone a phase transition from CuO to Cu2O. When the furnace temperature rises to 400℃, the intensity of the characteristic peak of CuO gradually weakens with the increase of temperature, while the intensity of the characteristic peak of Cu2O gradually increases, indicating that the content of Cu2O in the sample gradually increases. When the furnace temperature rises to 550℃, the characteristic peak of CuO in the Raman spectrum almost disappears, indicating that the content of Cu2O in the sample is high and the content of CuO is low. When the furnace temperature rises to 600℃, the intensity of the characteristic peak of Cu2O in the Raman spectrum weakens, while the intensity of the characteristic peak of CuO increases, indicating that the sample has undergone a reverse phase transition from Cu2O to CuO. Through Raman spectroscopy analysis, the phase changes of copper hydroxide at different annealing temperatures can be accurately determined. The experimental results show that at 200°C, copper hydroxide is completely dehydrated and converted to CuO. At 300°C, the sample undergoes a phase transition from CuO to Cu2O. From 400°C to 550°C, the Cu2O content in the sample gradually increases. At 550°C, the Cu2O content in the sample is the highest and the CuO content is the lowest. At 600°C, the sample undergoes a reverse phase transition from Cu2O to CuO. Therefore, 550°C is the optimal annealing temperature for obtaining high-purity Cu2O nanoneedles.

[0060] In the description of the present invention, it should be understood that the terms "longitudinal", "transverse", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0061] The embodiments described above are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by persons skilled in the art should fall within the scope of protection defined by the claims of the present invention.

Claims

1. A micro tube furnace capable of real-time observation, characterized in that: include: A housing (1) defines a mounting chamber in its center, and an exhaust pipe (2) communicating with the mounting chamber is provided at its bottom; A top plate (3) is provided covering the housing (1), and mounting holes are provided on the top plate (3) through the upper and lower surfaces corresponding to the upper opening of the mounting chamber, and the mounting holes are communicated with the upper opening; A plurality of air inlet pipes (4), one end of which is connected to the mounting hole, and the other end of which passes through the top plate (3) in a horizontal direction and extends to the outside; A quartz tube (5) is vertically arranged in the installation chamber; a corundum table (6), arranged inside the quartz tube (5) and close to the upper end of the quartz tube (5), and the corundum table (6) is used to place the calcined sample; An observation light window (7) is embedded in the inner surface of the mounting hole, and the observation light window (7) is located above the calcined sample.

2. A micro tube furnace capable of real-time observation according to claim 1, characterized in that: A high-temperature ceramic heating disc (8) is provided at the bottom of the installation chamber, and a high-temperature ceramic heating arc sheet (9) is provided on the inner side wall of the installation chamber; the high-temperature ceramic heating disc (8) is provided with a first through hole corresponding to the exhaust pipe (2).

3. The micro tube furnace capable of real-time observation according to claim 2, characterized in that: Four air inlet pipes (4) are provided, and the four air inlet pipes (4) are evenly spaced and arranged along the circumference of the top plate (3).

4. The micro tube furnace capable of real-time observation according to claim 3, characterized in that: A corundum base plate (10) is provided on the high-temperature ceramic heating disc (8), a second through hole is provided on the corundum base plate (10) corresponding to the exhaust pipe (2), and a guide groove is provided on the upper surface of the corundum base plate (10), wherein the guide groove can guide gas into the second through hole and discharge the gas through the first through hole and the exhaust pipe (2).

5. The micro tube furnace capable of real-time observation according to claim 1, characterized in that: A threaded steel ring (11) is provided on the upper edge of the quartz tube (5), and the threaded steel ring (11) is threadedly connected to the inner wall of the installation chamber.

6. The micro tube furnace capable of real-time observation according to claim 5, characterized in that: A sealing ring (12) is provided between the threaded steel ring (11) and the upper edge of the quartz tube (5).

7. The micro tube furnace capable of real-time observation according to claim 1, characterized in that: Also includes: The side plate (13) is U-shaped and has a side opening, and the side plate (13) is arranged to cover the side opening of the installation chamber.

8. The micro tube furnace capable of real-time observation according to claim 7, characterized in that: Also includes: a temperature sensor (14), embedded in the side plate (13), comprising a temperature probe and a temperature signal output line, wherein the temperature probe is located in the installation chamber, and the temperature signal output line is located outside the side plate (13); A pressure sensor (15) is embedded in the side plate (13) and has a pressure probe and a pressure signal output line. The pressure sensor (15) is located in the installation chamber, and the pressure signal output line is located outside the side plate (13).

9. The micro tube furnace capable of real-time observation according to claim 7, characterized in that: The top plate (3) and the outer shell (1) are connected via a longitudinal screw (16), and the outer shell (1) and the side plate (13) are connected via a transverse screw (17).

10. The micro tube furnace capable of real-time observation according to claim 1, characterized in that: The observation light window (7) is made of quartz glass.

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