Contact angle wetting testing device
By using graphite electrode heating sheet and sealing body design in the contact angle wetting test device, the problems of uneven heat field and high energy consumption in traditional devices are solved, and efficient and uniform high-temperature testing is achieved.
Patent Information
- Application Number
- CN202510365051.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-26
- Publication Date
- 2025-05-09
AI Technical Summary
Traditional contact angle wetting testing devices have problems such as uneven thermal field, oxidation failure and excessive energy consumption, which are difficult to meet the needs of high-temperature testing.
Graphite electrodes are used as heaters, and a heating sheet is used in each graphite electrode with a cross-sectional area smaller than the U-shaped arm to improve heating efficiency and reduce energy loss. The heating sheet is placed in the sealed cavity of the sealing body with the U-shaped arm outside to isolate the external environment and reduce heat loss.
It achieves heat concentration in the high-temperature zone, improves heating efficiency and temperature uniformity, extends the service life of the electrode, and ensures the stability of the test environment, and can be tested above 2000℃.
Smart Images
Figure CN119967645A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of testing equipment, and in particular to a contact angle wetting testing device. Background Art
[0002] The contact angle wetting test is a key method for studying the surface properties of materials. It is widely used in the fields of evaluating the interfacial bonding between molten metals and ceramic / metal substrates, optimizing high-temperature brazing processes, and analyzing the wettability of coating materials. For example, in the brazing process of aerospace high-temperature alloys, it is necessary to accurately measure the wetting angle of the molten solder on the surface of the base material to evaluate its spreading performance and interfacial bonding strength. Such tests usually need to be carried out in an inert gas or vacuum environment, and the samples need to be heated to more than 1,000 degrees Celsius to simulate actual working conditions, which places extremely high demands on the temperature control accuracy, thermal field uniformity, and environmental sealing of the heating device.
[0003] Traditional contact angle wetting test devices mostly use an independent resistance heating element (such as a molybdenum wire furnace, a carbon tube furnace) that surrounds the sample tube. In this test device, there is radiation heat loss between the heating element and the sample tube, which causes the high temperature area to deviate from the sample position, uneven thermal field distribution, severe electrode oxidation, and a complex structure. In addition, for some samples with higher temperature requirements, such as testing at 2000°C, this type of test device is generally difficult to meet the requirements. Summary of the invention
[0004] The object of the present invention is to provide a contact angle wetting test device with small heat loss and high achievable target temperature.
[0005] In order to achieve the above object, the present invention provides a contact angle wetting test device, which comprises:
[0006] A heating furnace, the heating furnace comprising a furnace body and a furnace chamber formed by the furnace body, wherein the furnace chamber has two oppositely arranged graphite electrodes;
[0007] Each of the graphite electrodes comprises two U-shaped arms separated from each other at one end and a heating plate at the other end, 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] A sealing body in a cylindrical structure is also provided in the furnace chamber, wherein a closed cavity is provided in the sealing body, the heating plate is located in the sealing body, and the U-shaped arm is located outside the sealing body;
[0010] The testing device further comprises a tube body that crosses the furnace chamber and the closed cavity, and the tube body is used to accommodate the sample to be tested and provide a testing environment;
[0011] The portion of the tube body located in the closed cavity is located between two oppositely arranged heating plates, and the heating plates are used to heat the tube body.
[0012] Preferably, the heating plate includes a plurality of bent portions extending in a cross shape.
[0013] Preferably, a plurality of first heat insulation plates stacked together are provided outside the sealing body and in the area of the U-shaped arm outside the sealing body, and the top of the U-shaped arm passes through the first heat insulation plate.
[0014] Preferably, a second heat insulation board is sleeved on the outer side of the first heat insulation board, and each of the second heat insulation boards sleeves a plurality of the first heat insulation boards together.
[0015] Preferably, the furnace body comprises an inner wall and an outer wall, a gap is provided between the inner wall and the outer wall, and a plurality of connecting rings are arranged between the inner wall and the outer wall and are spaced apart from the bottom to the top of the furnace body.
[0016] Preferably, the tube body includes an observation port at one end and a feed port at the other end, and the feed port is provided with a blocking plate detachably connected to the tube body; the observation port is used to provide an observation window for viewing the internal situation of the tube body, and the feed port is used to place a sample to be tested into the tube body.
[0017] Preferably, a thermocouple is further provided in the tube body, the hot end of the thermocouple is located at a position in the tube body corresponding to the closed cavity, and the cold end of the thermocouple passes through the blocking plate and is located outside the tube body.
[0018] Preferably, the feed port is further provided with a light projecting device, and the light projecting device is used to project illumination light into the tube body.
[0019] Preferably, a notch is provided on the side wall of the tube body near the feed port, and the light-projecting device includes a reflector, a light inlet tube and a light source; the reflector is provided at the notch inside the tube body, the light inlet tube is provided at the notch outside the tube body, 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 body.
[0020] Preferably, it further comprises a negative pressure extraction pipeline, which is connected to the tube body and is used to evacuate the tube body.
[0021] Compared with the prior art, the contact angle wetting test device provided by the above technical solution of the present invention adopts a graphite electrode as a heater, and in each graphite electrode, since the cross-sectional area of the heating plate is smaller than that of the U-shaped arm, the resistance of the heating plate is larger, and more heat is generated when current passes through. Such a design can concentrate heat in the heating plate area, improve heating efficiency, and reduce energy loss. Experiments have shown that a high temperature of more than 2000°C can be provided in the tube body. In addition, the heating plate is placed in a closed cavity of the sealing body, and the U-shaped arm is outside. This can isolate the external environment, prevent oxidation or contamination of the graphite electrode at high temperature, and extend the service life of the electrode. At the same time, the closed cavity reduces heat loss, improves thermal efficiency, and makes the heat more concentrated on the tube body, ensuring the stability of the test environment. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Figure 1 4 is a three-dimensional structural diagram of a testing device in an embodiment of the present invention.
[0023] Figure 2 It is a front view of the testing device in the embodiment of the present invention.
[0024] Figure 3 Schematic diagram of the planar structure of the graphite electrode in an embodiment of the present invention.
[0025] Figure 4 Schematic diagram of the connection structure of two graphite electrodes in the furnace body in an embodiment of the present invention.
[0026] Figure 5 Schematic diagram of the internal structure of the furnace body in the embodiment of the present invention.
[0027] Figure 6 It is a cross-sectional view of the furnace body and the tube body assembled together in an embodiment of the present invention.
[0028] Figure 7 2 is an exploded view of the furnace body in the embodiment of the present invention.
[0029] Figure 8 for Figure 7 Exploded view of part A in the middle. DETAILED DESCRIPTION
[0030] The present invention discloses a contact angle wetting test device, which is used to evaluate the wetting performance of a liquid on a material surface. The specific evaluation principle thereof belongs to the conventional technology in the art and will not be described in detail herein.
[0031] like Figures 1 to 6 The testing device in this embodiment includes a heating furnace 1 and a tube body 5 .
[0032] The heating furnace 1 comprises a furnace body 10, a furnace chamber 11 formed by the furnace body 10, and a furnace cover 12 which is arranged on the furnace body 10 to close the furnace chamber 11. The furnace chamber 11 has two graphite electrodes 2 (such as Figure 4 ), the graphite electrode 2 will generate heat when electricity is applied.
[0033] Each graphite electrode 2 includes two U-shaped arms 20 separated from each other at one end and a heating plate 21 at the other end, the two ends of the heating plate 21 are respectively connected to the two U-shaped arms 20, and the cross-sectional area of the heating plate 21 is smaller than the U-shaped arm 20. In this embodiment, the cross-sectional area of the heating plate 21 is more than twice the cross-sectional area of the U-shaped arm 20.
[0034] Since the cross-sectional area of the heating plate 21 is smaller than that of the U-shaped arm 20, according to the resistance formula, the resistance is inversely proportional to the cross-sectional area, so the resistance of the heating plate 21 is greater, and more heat is generated when current passes through. Such a design can concentrate heat in the heating plate 21 area, improve heating efficiency, and reduce energy loss. Tests show that a high temperature of more than 2000°C can be provided in the tube body 5.
[0035] One of the U-shaped arms 20 of the two graphite electrodes 2 is connected via a connector 23 , so that the two graphite electrodes 2 are connected in series in the heating circuit.
[0036] The two graphite electrodes 2 are connected in series through a U-shaped arm 20 to form a symmetrical current path. Such a design may make the current distribution more uniform, so that the heat generated by the heating plate 21 is more evenly distributed, ensuring that the sample in the tube 5 is heated evenly and improving the accuracy of the test. In addition, the series structure may simplify the circuit design, reduce the number of connecting components, and reduce the failure rate.
[0037] like Figure 6 and Figure 8 A sealing body 3 with a cylindrical structure is also provided in the furnace chamber 11 . The sealing body 3 has a closed cavity 30 . The heating plate 21 is located in the sealing body 3 , and the U-shaped arm 20 is located outside the sealing body 3 .
[0038] The testing device further comprises a tube body 5 which crosses the furnace chamber 11 and the closed cavity 30 . The tube body 5 is used to accommodate the sample to be tested and provide a testing environment.
[0039] The portion of the tube body 5 located in the closed cavity 30 is located between two oppositely disposed heating plates 21 , and the heating plates 21 are used to heat the tube body 5 .
[0040] In this embodiment, the heating plate 21 is placed in the sealed cavity 30 of the sealing body 3, and the U-shaped arm 20 is outside. This can isolate the external environment, prevent oxidation or contamination of the graphite electrode 2 at high temperature, and extend the service life of the electrode. At the same time, the sealed cavity 30 reduces heat loss, improves thermal efficiency, and makes the heat more concentrated on the target part of the tube body 5, ensuring the stability of the test environment.
[0041] In addition, the tube body 5 crosses the furnace chamber 11 and the closed cavity 30 and is located between the two heating plates 21. Such a position allows the sample to be directly at the center of the thermal field of the heating plate 21, and the heating is more direct and uniform. At the same time, the tube body 5 provides a test environment, and with the cooperation of the sealing body 3, it is easier to control the test atmosphere (such as inert gas or vacuum), avoid oxidation of the sample at high temperature, and ensure the accuracy of the test results.
[0042] When the test device provided in this embodiment is used, the two graphite electrodes 2 are connected to the heating circuit, the sample to be tested is placed in the portion of the tube body 5 corresponding to the closed cavity 30, and then the tube body 5 is evacuated or injected with an inert gas. Next, a current is applied to the two graphite electrodes 2, so that the heating plates 21 on the two graphite electrodes 2 generate heat, and the two heating plates 21 heat the tube body 5 located in the middle in the form of heat radiation, so that the ambient temperature in the tube body 5 increases until it reaches the temperature required for the test.
[0043] This testing device solves industry bottleneck problems such as uneven thermal field, oxidation failure and excessive energy consumption in traditional equipment.
[0044] On the other hand, Figure 3 The heating plate 21 includes a plurality of bent portions 22 extending in a "X" shape, thereby increasing the area of the heating plate 21 within a limited space and improving the heating efficiency of the heating plate 21.
[0045] On the other hand, Figures 6 to 8 A plurality of first heat insulation boards 40 are provided outside the sealing body 3 and in the area of the U-shaped arm 20 outside the sealing body 3, and the top of the U-shaped arm 20 passes through the first heat insulation board 40. The first heat insulation board 40 provides a higher heat preservation effect for the sealing body 3.
[0046] Furthermore, a second heat insulation board 41 is sleeved on the outer side of the first heat insulation board 40 , and each second heat insulation board 41 sleeves a plurality of first heat insulation boards 40 together.
[0047] In this embodiment, a plurality of second insulation boards 41 are sleeved on the outside of the multi-layered first insulation boards 40, wherein the height of each second insulation board 41 is much greater than the first insulation board 40. For example, one second insulation board 41 sleeves four first insulation boards 40 together, thereby forming an insulation unit that can be disassembled as a whole, and further improving the insulation effect.
[0048] On the other hand, Figure 6 The furnace body 10 includes an inner wall 100 and an outer wall 101, a gap 102 is provided between the inner wall 100 and the outer wall 101, and a plurality of connecting rings 103 are arranged between the inner wall 100 and the outer wall 101 and arranged at intervals from the bottom to the top of the furnace body 10, and the connecting rings 103 act as reinforcing ribs.
[0049] In this embodiment, the gap 102 between the inner wall 100 and the outer wall 101 acts as a heat insulator, reducing the heat transferred to the outer wall 101, thereby reducing the external temperature and improving safety. At the same time, the connecting ring 103 in the gap 102 acts as a reinforcing rib to enhance the structural strength of the furnace body 10 and prevent the inner wall 100 and the outer wall 101 from deforming or cracking at high temperatures.
[0050] In addition, the connecting rings 103 are arranged at intervals along the vertical direction of the furnace body 10, so that the structural support can be evenly distributed to 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, and the feed port 51 is provided with a plugging plate 52 detachably connected to the tube body 5, and the tube body 5 is sealed by the plugging plate 52. The observation port 50 is used to provide an observation window for viewing the internal conditions 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, a viewer (such as a long tube magnifying glass) 9 is also provided at one end of the observation port 50, and the sample condition in the tube body 5 is viewed through the viewer 9.
[0052] Furthermore, if Figure 2 and Figure 6 A thermocouple 6 is also provided in the tube body 5, the hot end 60 of the thermocouple 6 is located at a position corresponding to the closed cavity 30 in the tube body 5, and 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 in 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 port 51 is also provided with a light projecting device, which is used to project illumination light into the tube body 5 , so as to facilitate observation of the situation inside the tube body 5 through the observation port 50 .
[0054] Specifically, a notch 53 is provided on the side wall of the tube body 5 near the feed port, and the light projection device includes a reflector 70, a light inlet tube 71, and a light source 72. The reflector 70 is provided at the notch 53 inside the tube body 5, the light inlet tube 71 is provided 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, Figure 2 The testing device in this embodiment also includes a negative pressure extraction pipeline 8, which is connected to the tube body 5. The negative pressure extraction pipeline 8 is used to evacuate the tube body 5 to meet the vacuum environment requirements of the contact angle wetting test.
[0056] The above disclosure is only the preferred embodiment of the present invention, which certainly cannot be used to limit the scope of rights of the present invention. Therefore, equivalent changes made according to the scope of the patent application of the present invention are still within the scope covered by the present invention.
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 chamber formed by the furnace body, wherein the furnace chamber has two oppositely arranged graphite electrodes; Each of the graphite electrodes comprises two U-shaped arms separated from each other at one end and a heating plate at the other end, 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; A sealing body in a cylindrical structure is also provided in the furnace chamber, wherein a closed cavity is provided in the sealing body, the heating plate is located in the sealing body, and the U-shaped arm is located outside the sealing body; The testing device further comprises a tube body that crosses the furnace chamber and the closed cavity, and the tube body is used to accommodate the sample to be tested and provide a testing environment; The portion of the tube body located in the closed cavity is located between two oppositely arranged heating plates, and the heating plates are used to heat the tube body.
2. The contact angle wetting test device according to claim 1, characterized in that: The heating plate includes a plurality of bent portions extending in a "X" shape.
3. The contact angle wetting test device according to claim 1, characterized in that: A plurality of first heat insulation plates stacked together are sleeved outside the sealing body and in the area of the U-shaped arm outside the sealing body, and the top of the U-shaped arm passes through the first heat insulation plate.
4. The contact angle wetting test device according to claim 3, characterized in that: A second heat insulation board is also sleeved on the outer side of the first heat insulation board, and each of the second heat insulation boards sleeves a plurality of the first heat insulation boards together.
5. The contact angle wetting test device according to claim 1, characterized in that: The furnace body comprises an inner wall and an outer wall, a gap is provided between the inner wall and the outer wall, and a plurality of connecting rings are arranged between the inner wall and the outer wall and are spaced apart from the bottom to the top of the furnace body.
6. The contact angle wetting test device according to claim 1, characterized in that: The tube body includes an observation port at one end and a feed port at the other end, and the feed port is provided with a blocking plate detachably connected to the tube body; the observation port is used to provide an observation window for viewing the internal situation of the tube body, and the feed port is used to place a sample to be tested into the tube body.
7. The contact angle wetting test device according to claim 6, characterized in that: A thermocouple is also provided in the tube body, wherein the hot end of the thermocouple is located at a position in the tube body corresponding to the closed cavity, and the cold end of the thermocouple passes through the blocking plate and is located outside the tube body.
8. The contact angle wetting test device according to claim 6, characterized in that: The feed port is also provided with a light projecting device, and the light projecting device is used to project illumination light into the tube body.
9. The contact angle wetting test device according to claim 8, characterized in that: A notch is provided on the side wall of the tube body near the feed port, and the light-projecting device includes a reflector, a light inlet tube and a light source; the reflector is provided at the notch inside the tube body, the light inlet tube is provided at the notch outside the tube body, 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 body.
10. The contact angle wetting test device according to claim 1, characterized in that: It also includes a negative pressure extraction pipeline, which is connected to the tube body and is used to evacuate the tube body.