Contact angle wetting testing device

Abstract

The utility model discloses a contact angle wetting testing device, which comprises a heating furnace, a contact angle testing device and a control device, the heating furnace comprises a furnace body and a furnace chamber formed by the furnace body, and two oppositely arranged graphite electrodes are arranged in the furnace chamber; each graphite electrode comprises a U-shaped arm and a heating sheet, two ends of the heating sheet are respectively connected with the two U-shaped arms, and the cross sectional area of the heating sheet is smaller than that of the U-shaped arms; a sealing body of a barrel structure is further arranged in the furnace cavity, a closed cavity is formed in the sealing body, the heating piece is located in the sealing body, and the U-shaped arm is located outside the sealing body. The testing device further comprises a pipe body which transversely penetrates through the furnace chamber and the closed cavity, and the pipe body is used for accommodating a sample to be tested and providing a testing environment; the part, located in the closed cavity, of the pipe body is located between the two oppositely-arranged heating pieces, and the heating pieces are used for heating the pipe body. According to the contact angle wetting testing device, the heating efficiency is effectively improved, meanwhile, the energy loss is reduced, and the high temperature of 2000 DEG C or above can be provided for the interior of the pipe body.

Description

Technical Field

[0001] This utility model relates to the field of testing equipment technology, and in particular to a contact angle wetting test device. Background Technology

[0002] Contact angle wetting testing is a key method for studying material surface properties, widely used in areas such as evaluating the interfacial bonding between molten metal and ceramic / metal substrates, optimizing high-temperature brazing processes, and analyzing the wettability of coating materials. For example, in the brazing of high-temperature alloys for aerospace applications, it is necessary to accurately measure the wetting angle of the molten solder on the substrate material surface to evaluate its spreadability and interfacial bonding strength. Such tests typically require an inert gas or vacuum environment and necessitate heating the sample to over 1000 degrees Celsius to simulate actual operating conditions, placing extremely high demands on the temperature control accuracy, thermal uniformity, and environmental sealing of the heating device.

[0003] Traditional contact angle wetting test devices often employ an external design with a separate resistance heating element (such as a molybdenum wire furnace or a carbon tube furnace) surrounding the sample tube. This type of device suffers from radiative heat loss between the heating element and the sample tube, leading to high-temperature zones deviating from the sample position, uneven heat distribution, severe electrode oxidation, and a complex structure. Furthermore, for samples with stringent temperature requirements, such as those requiring testing at 2000℃, this type of device is generally unsuitable. Utility Model Content

[0004] The purpose of this invention is to provide a contact angle wetting test device with low heat loss and high achievable target temperature.

[0005] To achieve the above objectives, this utility model provides a contact angle wetting test device, which includes:

[0006] A heating furnace, the heating furnace comprising a furnace body and a furnace cavity formed by the furnace body, the furnace cavity having two oppositely arranged graphite electrodes;

[0007] Each of the graphite electrodes includes two U-shaped arms separated from each other at one end and a heating plate at the other end, wherein the two ends of the heating plate are respectively connected to the two U-shaped arms, and the cross-sectional area of ​​the heating plate is smaller than that of the U-shaped arms.

[0008] One of the U-shaped arms of the two graphite electrodes is connected so that the two graphite electrodes are connected in series in the heating circuit;

[0009] The furnace cavity is also provided with a cylindrical sealing body, which has a sealed cavity. The heating element is located in the sealing body, and the U-shaped arm is located outside the sealing body.

[0010] The testing device also includes a tube that runs through the furnace cavity and the sealed cavity, the tube being used to contain the sample to be tested and to provide a testing environment;

[0011] The portion of the tube located within the sealed cavity is situated between two opposing heating elements, which are used to heat the tube.

[0012] Preferably, the heating element includes a plurality of bent portions extending in a zigzag shape.

[0013] Preferably, a plurality of stacked first heat insulation plates are fitted over the outer surface of the sealing body and the area of ​​the U-shaped arm outside the sealing body, with the top of the U-shaped arm passing through the first heat insulation plates.

[0014] Preferably, a second heat insulation plate is also sleeved on the outside of the first heat insulation plate, and each second heat insulation plate sleeves multiple first heat insulation plates together.

[0015] Preferably, the furnace body includes an inner wall and an outer wall, with a gap between the inner wall and the outer wall, and a plurality of connecting rings arranged at intervals from the bottom to the top of the furnace body are provided between the inner wall and the outer wall.

[0016] Preferably, the tube includes an observation port at one end and a feed port at the other end, the feed port being provided with a plug that is detachably connected to the tube; the observation port is used to provide an observation window for viewing the internal condition of the tube, and the feed port is used to place the sample to be tested into the tube.

[0017] Preferably, a thermocouple is also provided inside the tube, with the hot end of the thermocouple located inside the tube at a position corresponding to the sealed cavity, and the cold end of the thermocouple passing through the blocking plate and located outside the tube.

[0018] Preferably, the feed inlet is also provided with a light-projecting device, which is used to project illumination light into the tube.

[0019] Preferably, a notch is provided on the side wall of the tube near the feed inlet, and the light projection device includes a reflector, a light inlet tube, and a light source; the reflector is disposed at the notch inside the tube, the light inlet tube is disposed at the notch outside the tube, the light source is located above the light inlet tube, and the reflector is used to reflect the light from the light inlet tube in a direction parallel to the central axis of the tube.

[0020] Preferably, it also includes a vacuum pipe, which is connected to the pipe body and is used to evacuate the pipe body.

[0021] Compared with existing technologies, the contact angle wetting test device provided by the present invention uses graphite electrodes as heaters. In each graphite electrode, because the cross-sectional area of ​​the heating element is smaller than that of the U-shaped arm, the resistance of the heating element is higher, generating more heat when current passes through. This design concentrates heat in the heating element area, improving heating efficiency while reducing energy loss. Tests show that it can provide temperatures above 2000℃ to the tube body. Furthermore, the heating element is placed inside a sealed cavity of the enclosure, while the U-shaped arm is on the outside. This isolates the external environment, preventing oxidation or contamination of the graphite electrode at high temperatures and extending the electrode's lifespan. Simultaneously, the sealed cavity reduces heat loss, improves thermal efficiency, and concentrates heat on the tube body, ensuring the stability of the testing environment. Attached Figure Description

[0022] Figure 1 This is a three-dimensional structural diagram of the testing device in an embodiment of this utility model.

[0023] Figure 2 This is a front view of the testing device in an embodiment of this utility model.

[0024] Figure 3 This is a planar structural diagram of the graphite electrode in an embodiment of this utility model.

[0025] Figure 4 This is a diagram showing the connection structure of two graphite electrodes in the furnace body in an embodiment of this utility model.

[0026] Figure 5 This is a diagram showing the internal structure of the furnace body in an embodiment of this utility model.

[0027] Figure 6 This is a cross-sectional view of the furnace body and tube body assembled together in an embodiment of this utility model.

[0028] Figure 7 This is an exploded view of the furnace body in an embodiment of this utility model.

[0029] Figure 8 for Figure 7 Exploded view of part A in the middle. Detailed Implementation

[0030] This utility model discloses a contact angle wetting test device, which is used to evaluate the wetting performance of liquid on material surface. The specific evaluation principle is a conventional technology in this field and will not be described in detail here.

[0031] like Figures 1 to 6 The testing apparatus in this embodiment includes a heating furnace 1 and a tube 5.

[0032] The heating furnace 1 includes a furnace body 10, a furnace cavity 11 formed by the furnace body 10, and a furnace cover 12 covering the furnace body 10 to seal the furnace cavity 11. The furnace cavity 11 contains two opposing graphite electrodes 2 (e.g., Figure 4 The graphite electrode 2 will generate heat when energized.

[0033] Each graphite electrode 2 includes two U-shaped arms 20 separated from each other at one end and a heating element 21 at the other end. The two ends of the heating element 21 are respectively connected to the two U-shaped arms 20, and the cross-sectional area of ​​the heating element 21 is smaller than that of the U-shaped arms 20. In this embodiment, the cross-sectional area of ​​the heating element 21 is more than twice the cross-sectional area of ​​the U-shaped arms 20.

[0034] Since the cross-sectional area of ​​the heating element 21 is smaller than that of the U-shaped arm 20, according to the resistance formula, resistance is inversely proportional to cross-sectional area. Therefore, the resistance of the heating element 21 is greater, and more heat will be generated when current passes through it. This design can concentrate heat in the area of ​​the heating element 21, improve heating efficiency, and reduce energy loss. Tests show that it can provide a high temperature of over 2000℃ inside the tube body 5.

[0035] One of the U-shaped arms 20 of the two graphite electrodes 2 is connected by a connector 23 so that the two graphite electrodes 2 are connected in series in the heating circuit.

[0036] Two graphite electrodes 2 are connected in series via a U-shaped arm 20, forming a symmetrical current path. This design may result in a more uniform current distribution, thereby ensuring a more uniform heat distribution from the heating element 21, guaranteeing uniform heating of the sample in the tube 5, and improving the accuracy of the test. Furthermore, the series structure may simplify circuit design, reduce connecting components, and lower the failure rate.

[0037] like Figure 6 and Figure 8 The furnace cavity 11 is also provided with a cylindrical sealing body 3, which has a sealed cavity 30 inside. The heating element 21 is located in the sealing body 3, and the U-shaped arm 20 is located outside the sealing body 3.

[0038] The testing apparatus also includes a tube 5 that runs through the furnace cavity 11 and the sealed cavity 30. The tube 5 is used to contain the sample to be tested and to provide the testing environment.

[0039] The portion of the tube body 5 located within the sealed cavity 30 is situated between two opposing heating elements 21, which are used to heat the tube body 5.

[0040] In this embodiment, the heating element 21 is placed inside the sealed cavity 30 of the sealing body 3, while the U-shaped arm 20 is on the outside. This isolates the external environment, preventing oxidation or contamination of the graphite electrode 2 at high temperatures and extending the electrode's lifespan. Simultaneously, the sealed cavity 30 reduces heat loss, improves thermal efficiency, and concentrates heat on the target portion of the tube 5, ensuring the stability of the testing environment.

[0041] In addition, the tube 5 runs through the furnace cavity 11 and the sealed cavity 30, located between the two heating elements 21. This position allows the sample to be directly in the center of the thermal field of the heating element 21, resulting in more direct and uniform heating. At the same time, the tube 5 provides the testing environment, and with the cooperation of the sealed body 3, it is easier to control the testing atmosphere (such as inert gas or vacuum), avoiding oxidation of the sample at high temperatures and ensuring the accuracy of the test results.

[0042] In use, the two graphite electrodes 2 are connected to the heating circuit, and the sample to be tested is placed in the tube 5 at the position corresponding to the sealed cavity 30. Then, the tube 5 is evacuated or injected with inert gas. Next, current is applied to the two graphite electrodes 2, causing the heating elements 21 on the two graphite electrodes 2 to heat up. The two heating elements 21 then heat the tube 5 located in the middle through thermal radiation, raising the ambient temperature inside the tube 5 until the required test temperature is reached.

[0043] This testing device solves industry bottlenecks such as uneven thermal field, oxidation failure, and excessive energy consumption in traditional equipment.

[0044] On the other hand, such as Figure 3 The heating element 21 includes several bent portions 22 extending in a Z-shape. This increases the area of ​​the heating element 21 within a limited space, thereby increasing the heating efficiency of the heating element 21.

[0045] On the other hand, such as Figures 6 to 8 A plurality of stacked first heat insulation plates 40 are fitted over the area of ​​the sealing body 3 and the U-shaped arm 20 outside the sealing body 3, with the top of the U-shaped arm 20 passing through the first heat insulation plate 40. The first heat insulation plate 40 provides a high heat insulation effect for the sealing body 3.

[0046] Furthermore, a second heat insulation plate 41 is also fitted on the outside of the first heat insulation plate 40, and each second heat insulation plate 41 fits together multiple first heat insulation plates 40.

[0047] In this embodiment, multiple second heat insulation plates 41 are sleeved on the outside of the multi-layered first heat insulation plate 40. The height of each second heat insulation plate 41 is much greater than that of the first heat insulation plate 40. For example, one second heat insulation plate 41 sleeves four first heat insulation plates 40 together to form a heat insulation unit that can be disassembled as a whole, and further improves the heat insulation effect.

[0048] On the other hand, such as Figure 6 The furnace body 10 includes an inner wall 100 and an outer wall 101. There is a gap 102 between the inner wall 100 and the outer wall 101, and a plurality of connecting rings 103 are arranged at intervals from the bottom to the top of the furnace body 10 between the inner wall 100 and the outer wall 101. The connecting rings 103 serve as reinforcing ribs.

[0049] In this embodiment, the gap 102 between the inner wall 100 and the outer wall 101 serves as heat insulation, reducing heat transfer to the outer wall 101, thereby lowering the external temperature and improving safety. Simultaneously, the connecting ring 103 in the gap 102 acts as a reinforcing rib, enhancing the structural strength of the furnace body 10 and preventing deformation or cracking of the inner wall 100 and outer wall 101 at high temperatures.

[0050] In addition, the connecting rings 103 are arranged at intervals along the vertical direction of the furnace body 10, which can evenly distribute the structural support and avoid local stress concentration. The connecting rings 103 can effectively resist the stress caused by thermal expansion and maintain the structural integrity of the furnace body 10.

[0051] On the other hand, the tube body 5 includes an observation port 50 at one end and a feed port 51 at the other end. The feed port 51 is provided with a stopper 52 that is detachably connected to the tube body 5, which seals the tube body 5. The observation port 50 provides an observation window for viewing the internal condition of the tube body 5, and the feed port 51 is used to place the sample to be tested into the tube body 5. In addition, an observer (such as a long-tube magnifying glass) 9 is provided at one end of the observation port 50, which is used to view the condition of the sample inside the tube body 5.

[0052] Furthermore, such as Figure 2 and Figure 6 A thermocouple 6 is also installed inside the tube body 5. The hot end 60 of the thermocouple 6 is located inside the tube body 5, corresponding to the sealed cavity 30, while the cold end 61 of the thermocouple 6 passes through the blocking plate 52 and is located outside the tube body 5. In this embodiment, the temperature inside the tube body 5 is monitored in real time by the thermocouple 6, and the heating power of the graphite electrode 2 can be dynamically adjusted according to the monitored temperature.

[0053] Furthermore, the feed inlet 51 is also equipped with a light-projecting device, which is used to project illumination light into the tube 5 so that the observation port 50 can observe the situation inside the tube 5.

[0054] Specifically, a notch 53 is provided on the side wall of the tube body 5 near the feed inlet. The light projection device includes a reflector 70, a light-inlet tube 71, and a light source 72. The reflector 70 is located at the notch 53 inside the tube body 5, the light-inlet tube 71 is located at the notch 53 outside the tube body 5, and the light source 72 is located above the light-inlet tube 71. The reflector 70 is used to reflect the light from the light-inlet tube 71 in a direction parallel to the central axis of the tube body 5, thereby illuminating the inside of the tube body 5.

[0055] On the other hand, such as Figure 2 The testing device in this embodiment also includes a negative pressure extraction pipe 8, which is connected to the tube body 5. The negative pressure extraction pipe 8 is used to evacuate the tube body 5 to meet the vacuum environment requirements of the contact angle wetting test.

[0056] The above-disclosed embodiments are merely preferred embodiments of the present utility model and should not be construed as limiting the scope of the present utility model. Therefore, any equivalent variations made in accordance with the scope of the present utility model application shall still fall within the scope of the present utility model.

Claims

1. A contact angle wetting test device, characterized in that, include: A heating furnace, the heating furnace comprising a furnace body and a furnace cavity formed by the furnace body, the furnace cavity having two oppositely arranged graphite electrodes; Each of the graphite electrodes includes two U-shaped arms separated from each other at one end and a heating plate at the other end, wherein the two ends of the heating plate are respectively connected to the two U-shaped arms, and the cross-sectional area of ​​the heating plate is smaller than that of the U-shaped arms. One of the U-shaped arms of the two graphite electrodes is connected so that the two graphite electrodes are connected in series in the heating circuit; The furnace cavity is also provided with a cylindrical sealing body, which has a sealed cavity. The heating element is located in the sealing body, and the U-shaped arm is located outside the sealing body. The testing device also includes a tube that runs through the furnace cavity and the sealed cavity, the tube being used to contain the sample to be tested and to provide a testing environment; The portion of the tube located within the sealed cavity is situated between two opposing heating elements, which are used to heat the tube.

2. The contact angle wetting test device according to claim 1, characterized in that, The heating element includes several bent portions extending in a zigzag shape.

3. The contact angle wetting test device according to claim 1, characterized in that, A plurality of first heat insulation plates are fitted over the outer surface of the sealing body and the area of ​​the U-shaped arm outside the sealing body, with the top of the U-shaped arm passing through the first heat insulation plates.

4. The contact angle wetting test device according to claim 3, characterized in that, A second heat insulation plate is also fitted on the outside of the first heat insulation plate, and each second heat insulation plate fits together multiple first heat insulation plates.

5. The contact angle wetting test device according to claim 1, characterized in that, The furnace body includes an inner wall and an outer wall, with a gap between the inner wall and the outer wall, and a plurality of connecting rings arranged at intervals from the bottom to the top of the furnace body are provided between the inner wall and the outer wall.

6. The contact angle wetting test apparatus according to claim 1, characterized in that, The tube includes an observation port at one end and a feed port at the other end. The feed port is provided with a stopper plate that is detachably connected to the tube. The observation port is used to provide an observation window to view the internal condition of the tube, and the feed port is used to place the sample to be tested into the tube.

7. The contact angle wetting test apparatus according to claim 6, characterized in that, A thermocouple is also installed inside the tube. The hot end of the thermocouple is located inside the tube at a position corresponding to the sealed cavity, and the cold end of the thermocouple passes through the blocking plate and is located outside the tube.

8. The contact angle wetting test apparatus according to claim 6, characterized in that, The feed inlet is also equipped with a light-projecting device, which is used to project illumination light into the tube.

9. The contact angle wetting test apparatus according to claim 8, characterized in that, A notch is provided on the side wall of the tube near the feed inlet. The light projection device includes a reflector, a light inlet tube, and a light source. The reflector is located at the notch inside the tube, the light inlet tube is located at the notch outside the tube, and the light source is located above the light inlet tube. The reflector is used to reflect the light from the light inlet tube in a direction parallel to the central axis of the tube.

10. The contact angle wetting test apparatus according to claim 1, characterized in that, It also includes a negative pressure extraction pipe, which is connected to the pipe body and is used to evacuate the pipe body.

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