A computer internal structure and testing device based on metal phase change contact thermal resistance

Abstract

The present invention relates to the field of computer heat dissipation technology, and in particular to a computer internal structure and testing device based on metal phase change contact thermal resistance, comprising a first heat dissipation structure, a second heat dissipation structure, a third heat dissipation structure, and a fourth heat dissipation structure, wherein the first heat dissipation structure comprises a chassis cover, a frame, and a first liquid metal foil, wherein the first liquid metal foil is disposed between the chassis cover and the frame; the frame is provided with a first contact groove, into which the first liquid metal foil is inserted; the first liquid metal foil, the second liquid metal foil, the third liquid metal foil, and the fourth liquid metal foil are all made of indium alloy material. In the present invention, the liquid metal foil fills the gaps between the contact surfaces inside the computer when melted at high temperature, thereby effectively reducing the contact thermal resistance inside the computer and improving the heat dissipation efficiency. At the same time, the design of the contact groove and the collection groove avoids the generation of excess material inside the computer, thereby improving the reliability of the computer.

Description

Technical Field

[0001] The present invention relates to the technical field of computer heat dissipation, and in particular to a computer internal structure and a testing device based on metal phase change contact thermal resistance. Background Art

[0002] As computers evolve toward higher power, smaller form factors, and greater integration, the increased power consumption and integration of components lead to higher heat flux densities within the devices, which in turn increases internal temperatures. If this heat can't be dissipated quickly, thermal reliability issues can develop. During the heat dissipation process of missile-mounted computers, the combined thermal resistances of components, printed circuit boards, heat sinks, and chassis walls create the junction-to-ambient thermal resistance, which directly impacts the overall temperature distribution and heat dissipation, ultimately affecting the quality and reliability of the entire product.

[0003] The thermal resistance of each link is composed of material thermal resistance and contact thermal resistance. Material thermal resistance is determined by the material's thermophysical properties, while contact thermal resistance is caused by the presence of a tiny gap between two objects when they come into contact, resulting in an actual contact area of less than 10% of the contact surface. Reducing material thermal resistance usually requires replacing the material, but replacing materials requires considering the influence of various factors such as electromagnetics and mechanics. Therefore, in the heat dissipation design of computer products, reducing contact thermal resistance is often used to lower the product's operating temperature and extend its service life.

[0004] Thermal interface materials (TIMs) are widely used in computer cooling, serving as a preferred method for reducing contact thermal resistance. Their primary function is to fill the gap between the heat source and the heat sink, displacing air trapped within. This allows heat generated by the heat source to be transferred more quickly through the TIM, thereby reducing operating temperatures. Common TIMs include thermal pads, thermal grease, and thermal gel. Most thermal pads have a thermal conductivity of 3W / m·K, while thermal grease and thermal adhesive generally do not exceed 6W / m·K. In addition, some newer TIMs, such as phase-change TIMs, have a thermal conductivity of no more than 3W / m·K. These materials are solid at room temperature, but when the operating temperature reaches their melting point, they become similar to thermal grease, losing their viscosity and flowing through the thermally bonded parts to fill the gaps. Synthetic graphite, made from organic polyester film and sintered at high temperatures, has a transverse thermal conductivity of up to 1800W / m·K and a longitudinal thermal conductivity of approximately 15W / m·K.

[0005] These thermal interface materials are widely used in computers. However, as computer power consumption increases, traditional thermal interface materials have low thermal conductivity and insufficient contact with the interface, making them inadequate for the heat dissipation requirements of new devices. In harsh environments, effectively reducing the contact thermal resistance within the computer chassis and providing a good heat dissipation path is a major challenge hindering the development of weaponry. Summary of the Invention

[0006] In response to the problems existing in the prior art, the present invention provides a computer internal structure and testing device based on metal phase change contact thermal resistance, which can quickly fill the gaps between the contact surfaces inside the computer when melted at high temperature, effectively reducing the contact thermal resistance inside the computer and improving the heat dissipation efficiency. At the same time, the design of the contact groove and collection groove avoids the generation of excess materials inside the computer, greatly improving the reliability of the computer.

[0007] The present invention is achieved through the following technical solutions:

[0008] A computer internal structure based on metal phase change contact thermal resistance includes a first heat dissipation structure, a second heat dissipation structure, a third heat dissipation structure, and a fourth heat dissipation structure. The first heat dissipation structure includes a chassis cover, a frame, and a first liquid metal foil. The first liquid metal foil is disposed between the chassis cover and the frame. The frame is provided with a first contact groove, and the first liquid metal foil is inserted into the first contact groove.

[0009] The second heat dissipation structure includes a frame boss, a printed circuit board, and a second liquid metal foil, wherein the second liquid metal foil is arranged between the frame boss and the printed circuit board; a second contact groove is provided on the frame boss, and the second liquid metal foil is inserted into the second contact groove;

[0010] The third heat dissipation structure includes a bottom cover plate, a common heat dissipation device, and a third liquid metal foil, wherein the third liquid metal foil is arranged between the bottom cover plate and the common heat dissipation device; a third contact groove is provided on the bottom cover plate, and the third liquid metal foil is inserted into the third contact groove;

[0011] The fourth heat dissipation structure includes an insulating heat dissipation device, a heat dissipation platform, a fourth liquid metal foil and an insulating film, wherein the heat dissipation platform is arranged on the bottom cover plate, and the fourth liquid metal foil and the insulating film are stacked and arranged between the insulating heat dissipation device and the heat dissipation platform;

[0012] The first liquid metal foil, the second liquid metal foil, the third liquid metal foil and the fourth liquid metal foil are all made of indium alloy materials.

[0013] Preferably, the insulating film is made of polyimide material.

[0014] Preferably, the frame is further provided with a first collecting groove, which is arranged on the outside of the first contact groove; the depth of the first collecting groove is the same as the depth of the first contact groove.

[0015] Preferably, a second collecting groove is further provided on the frame boss, and the second collecting groove is arranged outside the second contact groove.

[0016] Preferably, the second contact groove and the second collecting groove are both annular.

[0017] Preferably, the depth of the second collecting groove is the same as the depth of the second contact groove.

[0018] Preferably, an annular third collecting groove is further provided outside the third contact groove, and the depth of the third collecting groove is the same as the depth of the third contact groove.

[0019] Preferably, a fastening stud is provided on the outer side of the common heat dissipation device, one end of the fastening stud is fixedly connected to the cover plate, and the other end is connected to the printed circuit board.

[0020] A testing device based on metal phase change contact thermal resistance, comprising a testing device, a constant temperature cold plate, a heating plate, a computer and a plurality of thermocouples, wherein the testing device comprises a water bath, a temperature tester and a constant current power supply, wherein the water outlet of the water bath is connected to the water inlet of the constant temperature cold plate, and the water outlet of the constant temperature cold plate is connected to the water inlet of the water bath; a locking device is provided on the constant temperature cold plate, and the heating plate is arranged on the constant temperature cold plate through the locking device, and the heating plate is connected to the constant current power supply; one end of the thermocouple contacts the test sample, and the other end contacts the test sample. The end is connected to the input end of the temperature tester, and the output end of the temperature tester is connected to the input end of the computer; during the test, the test sample is set between the heating plate and the constant temperature cold plate through the locking device, and the test sample includes a first sample plate, a second sample plate and a liquid metal foil, and the first sample plate is provided with a contact groove and a collection groove, the collection groove is arranged outside the contact groove, and the liquid metal foil is arranged in the contact groove; the first sample plate and the second sample plate are both provided with multiple temperature measuring grooves, and the thermocouples correspond to the temperature measuring grooves one by one, and the thermocouples are in contact with the temperature measuring grooves.

[0021] Preferably, both the locking device and the test sample are provided with a heat-insulating covering.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The present invention discloses a computer internal structure based on metal phase change contact thermal resistance, which is achieved by arranging a liquid metal foil of indium alloy material in the heat dissipation structure, with a density of 6.5g / cm 3 Its melting point can be adjusted within 50℃~200℃ according to the operating temperature of the computer. Its thermal conductivity is between 70W / m·K and 80W / m·K. It has strong oxidation resistance and a volatility rate of no more than 0.001%. It has a long service life, thereby effectively reducing the contact thermal resistance of internal components, printed circuit boards, radiators, and chassis walls.

[0024] When the computer temperature reaches the operating temperature of the liquid metal foil, the foil begins to melt, and its state is similar to thermal grease. It expands slightly in volume and contacts the cover plate on the surface of the contact groove of the frame, filling the micro gaps and rough surface between the two.

[0025] If too much foil is used, after the contact surface is filled, the grease-like foil will begin to spread to the sides of the frame and then flow into the collection tank without flowing outside the entire contact surface. Liquid metal is a thermal interface material with extremely high thermal conductivity and good filling effect.

[0026] The contact groove can prevent the liquid metal foil from being placed between the contact surface of the cover and the frame, reducing the contact thermal resistance caused by the height of the liquid metal foil; the function of the collection groove is to collect excess grease-like liquid metal produced when the foil melts, avoiding the generation of excess materials inside the chassis in harsh working environments (high temperature, vibration, impact, etc.), which may affect the performance of the entire machine.

[0027] The insulating film within the fourth heat dissipation structure enhances insulation performance and ensures computer reliability. When the foil melts, it pushes against the insulating film on the surface of the heat dissipation device, filling the entire device surface and significantly reducing the thermal contact resistance.

[0028] In a testing device based on metal phase change contact thermal resistance, a constant-temperature fluid enters a constant-temperature cold plate through a water outlet and a pipeline, maintaining the plate's temperature. The fluid then flows back through the pipeline to the water inlet of the testing device, where it cools and then enters the water outlet, thus recycling the fluid. A locking device secures the sample and applies varying amounts of pressure. A heating plate provides a heat source, while a constant-temperature power supply provides the required heating power.

[0029] The thermocouple is connected to the temperature tester, and the temperature tester is connected to the computer. The real-time temperatures of multiple temperature measuring baths under different working conditions are recorded through the computer and the test equipment.

[0030] During the test, the heat of the heating plate is transferred to the contact surface through the first sample plate. The liquid metal foil in the contact groove melts and fills the contact surface. The heat passes through the contact surface to the second sample plate, and is then transferred from the second sample plate to the constant temperature cold plate.

[0031] Using the steady-state contact thermal resistance calculation method, combined with heating power consumption and temperature measurement data, the contact thermal resistance between test samples can be measured. Comparison with test samples without liquid metal foil effectively demonstrates that the liquid metal foil significantly reduces contact thermal resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 Schematic diagram of the three-dimensional structure of the computer in the present invention;

[0033] Figure 2 A schematic diagram of the structure decomposition of the computer in the present invention;

[0034] Figure 3 Schematic diagram of the contact between the upper and lower cover plates and the frame in the present invention;

[0035] Figure 4 Schematic diagram of the contact between the printed circuit board and the frame in the present invention;

[0036] Figure 5 Schematic diagram of the contact between the heat dissipation device and the lower bottom cover plate in the present invention;

[0037] Figure 6 Schematic diagram of the contact between the heat dissipation device with insulation requirements and the lower bottom cover plate in the present invention;

[0038] Figure 7 This is the contact thermal resistance testing system of the present invention.

[0039] In the figure, 1. computer; 2. chassis cover; 3. countersunk screw; 4. printed circuit board; 5. first liquid metal foil; 6. frame; 7. bottom cover; 8. third liquid metal foil; 9. insulating film; 10. second liquid metal foil; 11. ordinary heat sink; 12. connector; 13. flat-head screw; 14. first contact slot; 15. first collecting slot; 16. second contact slot; 17. second collecting slot; 18. third contact slot; 19. third collecting slot; 20. insulating heat sink; 21. computer; 22. constant temperature cold plate; 23. heating plate; 24. first sample; 25. second sample; 26. liquid metal foil; 27. testing equipment; 28. fourth liquid metal foil. DETAILED DESCRIPTION

[0040] The present invention will be further described in detail below with reference to specific embodiments, which are intended to explain the present invention rather than to limit it.

[0041] The present invention discloses a computer internal structure based on metal phase change contact thermal resistance, referring to Figure 1 、 2 and 3, including a first heat dissipation structure, a second heat dissipation structure, a third heat dissipation structure and a fourth heat dissipation structure, the first heat dissipation structure includes a chassis cover 2, a frame 6 and a first liquid metal foil 5, and the chassis cover 2 is connected to the frame 6 by a countersunk screw 3.

[0042] The first liquid metal foil 5 is disposed between the chassis cover 2 and the frame 6. The frame 6 is provided with a first contact groove 14, into which the first liquid metal foil 5 is inserted. The dimensions of the first liquid metal foil 5 are the same as those of the first contact groove 14. The frame 6 is also provided with a first annular collection groove 15, which is disposed outside the first contact groove 14. The depth of the first collection groove 15 is the same as that of the first contact groove 14.

[0043] Reference Figure 4The second heat dissipation structure includes a frame boss, a printed circuit board 4, and a second liquid metal foil 10. The printed circuit board 4 is connected to the frame 6 via flat-head screws 13. The second liquid metal foil 10 is disposed between the frame boss and the printed circuit board 4. A second contact groove 16 is provided on the frame boss, into which the second liquid metal foil 10 is inserted. The dimensions of the second liquid metal foil 10 are the same as those of the second contact groove 16. A second collection groove 17 is also provided on the frame boss, located outside the second contact groove 16. Both the second contact groove 16 and the second collection groove 17 are annular and have the same depth.

[0044] Reference Figure 5 The third heat dissipation structure includes a bottom cover plate 7, a conventional heat dissipation device 11, and a third liquid metal foil 8. The third liquid metal foil 8 is disposed between the bottom cover plate 7 and the conventional heat dissipation device 11. The bottom cover plate 7 is provided with a third contact groove 18, into which the third liquid metal foil 8 is inserted. The dimensions of the third liquid metal foil 8 are the same as those of the third contact groove 18. An annular third collection groove 19 is also provided outside the third contact groove 18. The depth of the third collection groove 19 is the same as that of the third contact groove 18.

[0045] Reference Figure 2 、 6 The fourth heat dissipation structure includes an insulating heat dissipation device 20, a heat dissipation platform, a fourth liquid metal foil 28, and an insulating film 9. The insulating heat dissipation device 20 is connected to the printed circuit board 4; the heat dissipation platform is disposed on the bottom cover plate 7, and the fourth liquid metal foil 28 is disposed between the insulating heat dissipation device 20 and the heat dissipation platform. The heat dissipation platform is provided with a fourth contact groove and a fourth collection groove. The fourth liquid metal foil 28 and the insulating film 9 are superimposed and disposed in the fourth contact groove between the insulating heat dissipation device 20 and the heat dissipation platform. The fourth collection groove is disposed outside the fourth contact groove. The insulating film 9 is made of polyimide material and has a thickness of 0.01 mm in this embodiment.

[0046] The first liquid metal foil 5, the second liquid metal foil 10, the third liquid metal foil 8 and the fourth liquid metal foil 28 are all made of indium alloy. Indium alloy has a density of 6.5 g / cm 3 The melting point can be adjusted between 50°C and 200°C depending on the computer's operating temperature. Its thermal conductivity ranges from 70W / m·K to 80W / m·K. It exhibits strong oxidation resistance, a volatility rate of no more than 0.001%, and a long service life. When the first, second, third, and fourth liquid metal foils 5, 10, 8, and 28 melt at high temperatures, they fill the micro-gaps and rough surfaces between the contact surfaces, thereby reducing the thermal contact resistance between the contact surfaces.

[0047] A fastening stud is integrally provided on the chassis cover 2 , and the other end of the fastening stud is connected to the screw on the printed circuit board 4 .

[0048] Reference Figure 1 The computer 1 also includes a connector 12 for connecting to external devices.

[0049] A test device based on metal phase change contact thermal resistance, referring to Figure 7 The test equipment 27 includes a constant temperature cold plate 22, a heater 23, a computer 21, and multiple thermocouples. The test equipment 27 includes a water bath, a temperature tester, and a constant current power supply. The water outlet of the water bath is connected to the water inlet of the constant temperature cold plate 22 via a water pipe, and the water outlet of the constant temperature cold plate 22 is connected to the water inlet of the water bath via a water pipe to achieve fluid circulation. The test equipment 27 also includes a cold source for cooling the recovered fluid.

[0050] A locking device is provided on the constant temperature cold plate 22. The heater plate 23 is secured to the plate via the locking device. The heater plate 23 is connected to a constant current power supply to provide heating power. The locking device is used to secure the test specimen and apply a load to the test specimen. In this embodiment, the locking device is a bolt that extends through the constant temperature cold plate and contacts the test specimen.

[0051] One end of the thermocouple is in contact with the test sample, and the other end is connected to the input end of the temperature tester. The output end of the temperature tester is connected to the input end of the computer 21.

[0052] The test sample includes a first sample plate 24, a second sample plate 25 and a liquid metal foil 26. The first sample plate 24 is provided with a contact groove and a collection groove. The collection groove is arranged outside the contact groove, and the liquid metal foil 26 is arranged in the contact groove; the first sample plate 24 and the second sample plate 25 are both provided with multiple temperature measuring grooves, and the thermocouples correspond to the temperature measuring grooves one by one, and the thermocouples are in contact with the temperature measuring grooves.

[0053] Both the locking device and the test sample are provided with a heat-insulating covering member. In this embodiment, the heat-insulating covering member is made of rubber material.

[0054] During testing, the test specimen is positioned between the heating plate 23 and the constant temperature cold plate 22 via a locking device. In this embodiment, five temperature measuring slots are provided on both the first sample plate 24 and the second sample plate 25. During testing, thermocouples are inserted into the test specimen and secured. Computer 21 and testing equipment 27 record the real-time temperatures at ten measuring points under different operating conditions.

[0055] Heat from the heater 23 is transferred to the contact surface via the first sample 24. The liquid metal foil 26 in the contact groove melts, filling the contact surface. The heat then flows through the contact surface to the second sample 25, where it is then transferred to the constant-temperature cold plate 22. A computer 21 and a temperature meter record the real-time temperatures at multiple measurement points under different operating conditions. Using the steady-state contact thermal resistance calculation method, combined with heating power consumption and temperature measurement data, the contact thermal resistance between the test samples can be measured.

[0056] The above description is merely a preferred embodiment of the present invention and is not intended to impose any limitation on the technical solution of the present invention. Those skilled in the art should understand that, without departing from the spirit and principles of the present invention, the technical solution can also be subjected to several simple modifications and replacements, and these modifications and replacements are also within the scope of protection covered by the claims.

Claims

1. A computer internal structure based on metal phase change contact thermal resistance, characterized in that: The invention comprises a first heat dissipation structure, a second heat dissipation structure, a third heat dissipation structure and a fourth heat dissipation structure, wherein the first heat dissipation structure comprises a chassis cover (2), a frame (6) and a first liquid metal foil (5), wherein the first liquid metal foil (5) is arranged between the chassis cover (2) and the frame (6); a first contact groove (14) is provided on the frame (6), and the first liquid metal foil (5) is plugged into the first contact groove (14); The second heat dissipation structure comprises a frame boss, a printed circuit board (4), and a second liquid metal foil (10), wherein the second liquid metal foil (10) is arranged between the frame boss and the printed circuit board (4); a second contact groove (16) is provided on the frame boss, and the second liquid metal foil (10) is inserted into the second contact groove (16); The third heat dissipation structure comprises a bottom cover plate (7), a common heat dissipation device (11) and a third liquid metal foil (8), wherein the third liquid metal foil (8) is arranged between the bottom cover plate (7) and the common heat dissipation device (11); a third contact groove (18) is provided on the bottom cover plate (7), and the third liquid metal foil (8) is plugged into the third contact groove (18); The fourth heat dissipation structure comprises an insulating heat dissipation device (20), a heat dissipation platform, a fourth liquid metal foil (28) and an insulating film (9); the heat dissipation platform is arranged on the bottom cover plate (7); the fourth liquid metal foil (28) and the insulating film (9) are superimposed and arranged between the insulating heat dissipation device (20) and the heat dissipation platform; The first liquid metal foil (5), the second liquid metal foil (10), the third liquid metal foil (8) and the fourth liquid metal foil (28) are all made of indium alloy material.

2. The computer internal structure based on metal phase change contact thermal resistance according to claim 1, characterized in that: The insulating film (9) is made of polyimide material.

3. The computer internal structure based on metal phase change contact thermal resistance according to claim 1, characterized in that: The frame (6) is further provided with a first collecting groove (15), which is arranged outside the first contact groove (14); the depth of the first collecting groove (15) is the same as the depth of the first contact groove (14).

4. The computer internal structure based on metal phase change contact thermal resistance according to claim 1, characterized in that: A second collecting groove (17) is also provided on the boss of the frame (6), and the second collecting groove (17) is arranged outside the second contact groove (16).

5. The computer internal structure based on metal phase change contact thermal resistance according to claim 4, characterized in that: The second contact groove (16) and the second collecting groove (17) are both annular.

6. The computer internal structure based on metal phase change contact thermal resistance according to claim 4, characterized in that: The depth of the second collecting groove (17) is the same as the depth of the second contact groove (16).

7. The computer internal structure based on metal phase change contact thermal resistance according to claim 1, characterized in that: An annular third collecting groove (19) is further provided outside the third contact groove (18), and the depth of the third collecting groove (19) is the same as the depth of the third contact groove (18).

8. The computer internal structure based on metal phase change contact thermal resistance according to claim 1, characterized in that: A fastening stud is provided on the outside of the heat dissipation device, one end of the fastening stud is fixedly connected to the cover plate, and the other end is connected to the printed circuit board (4).

9. A testing device based on metal phase change contact thermal resistance, used for testing the first heat dissipation structure, the second heat dissipation structure, the third heat dissipation structure and the fourth heat dissipation structure in the internal structure of a computer based on metal phase change contact thermal resistance according to any one of claims 1 to 8, characterized in that: The invention comprises a test device (27), a constant temperature cold plate (22), a heating plate (23), a computer (21) and a plurality of thermocouples, wherein the test device (27) comprises a water bath, a temperature tester and a constant current power supply, the water outlet of the water bath is connected to the water inlet of the constant temperature cold plate (22), and the water outlet of the constant temperature cold plate (22) is connected to the water inlet of the water bath; a locking device is provided on the constant temperature cold plate (22), the heating plate (23) is arranged on the constant temperature cold plate (22) through the locking device, and the heating plate (23) is connected to the constant current power supply; one end of the thermocouple is in contact with the test sample, and the other end is in contact with the temperature tester The input end of the temperature tester is connected to the input end of the computer (21); the output end of the temperature tester is connected to the input end of the computer (21); during testing, the test sample is set between the heating plate (23) and the constant temperature cold plate (22) through a locking device, and the test sample includes a first sample plate (24), a second sample plate (25) and a liquid metal foil (26), the first sample plate (24) is provided with a contact groove and a collection groove, the collection groove is set outside the contact groove, and the liquid metal foil (26) is set in the contact groove; the first sample plate (24) and the second sample plate (25) are both provided with a plurality of temperature measuring grooves, the thermocouples correspond to the temperature measuring grooves one by one, and the thermocouples are in contact with the temperature measuring grooves.

10. The testing device based on metal phase change contact thermal resistance according to claim 9, characterized in that: The locking device and the test sample are both provided with heat-insulating covering parts.

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