Vapor chamber manufacturing method, vapor chamber and electronic equipment

Abstract

The invention provides a vapor chamber manufacturing method, a vapor chamber and electronic equipment, and relates to the technical field of heat dissipation device manufacturing. In the manufacturing method of the vapor chamber, after the vapor chamber body is obtained, the passivation solution containing the strong oxidant is at least injected into the cavity of the vapor chamber body, so that the inner wall surface of the vapor chamber body can be promoted to be fully oxidized. Afterwards, the vapor chamber body is placed in a pressure-bearing furnace, heat preservation is conducted on the vapor chamber body for preset time at the preset temperature, passivation treatment is conducted on the vapor chamber body, so that the reaction progress of the wall face of the vapor chamber body is strengthened, and the vapor chamber body is fully passivated. And after passivation treatment is finished, the vapor chamber body is taken out and subjected to post-treatment, and the vapor chamber body attached with a passivation film is obtained. Thus, the passivation quality of the vapor chamber body can be improved, a uniform, compact and complete passivation film can be formed on the inner wall face of the vapor chamber body, the corrosion resistance and reliability of the vapor chamber can be improved, and the heat dissipation performance of electronic equipment is improved.

Description

Technical Field

[0001] The present application relates to the technical field of heat dissipation device manufacturing, and particularly relates to a manufacturing method of a vapor chamber, a vapor chamber and an electronic device. Background Art

[0002] The thinning of electronic devices such as mobile phones and tablet computers has become a trend. As a heat dissipation device for electronic devices, the demand for the thinning of the vapor chamber (VC) is also increasing day by day.

[0003] Currently, the vapor chambers widely used in electronic devices are mainly made of copper alloy as the main material. However, due to the high density of copper alloy, it is difficult to meet the application requirements of further thinning. Therefore, it is necessary to use other metals with lower density and excellent mechanical properties as the main material of the vapor chamber. And based on the heat conduction principle of the vapor chamber, this metal should also have good corrosion resistance. Metals such as stainless steel, titanium alloy and their composite materials have lower density and higher strength than copper. At the same time, the passivation film on their surface can improve their corrosion resistance, and it is expected to achieve further thinning of the vapor chamber.

[0004] However, in the natural state, the passivation films on the surfaces of metals such as stainless steel, titanium alloy and their composite materials are difficult to meet the reliability requirements of the vapor chamber. Summary of the Invention

[0005] The present application provides a manufacturing method of a vapor chamber, a vapor chamber and an electronic device. The manufacturing method of the vapor chamber can form a uniform, dense and complete passivation film on the inner wall surface of the vapor chamber, which can improve the corrosion resistance and reliability of the vapor chamber and enhance the heat dissipation performance of the electronic device.

[0006] The first aspect of the present application provides a manufacturing method of a vapor chamber, including:

[0007] Obtain a vapor chamber body;

[0008] Provide a passivation solution containing a strong oxidant, and inject the passivation solution into at least the cavity of the vapor chamber body;

[0009] Place the vapor chamber body in a pressure-bearing furnace and perform passivation treatment at a preset temperature and for a predetermined time; wherein, the pressure in the pressure-bearing furnace > 0.1 MPa;

[0010] Take out the vapor chamber body and perform post-treatment on the vapor chamber body to obtain a vapor chamber body with a passivation film attached thereto.

[0011] The manufacturing method of the heat pipe provided by the present application, after obtaining the heat pipe body, by using a passivation solution containing a strong oxidant, injecting the passivation solution into at least the cavity of the heat pipe body can promote the full oxidation of the inner wall surface of the heat pipe body, which helps to improve the passivation quality of the heat pipe body. Then, place the heat pipe body in a pressure-bearing furnace, keep the heat pipe body at a preset temperature for a predetermined time, and perform passivation treatment on the heat pipe body to strengthen the reaction process of the wall surface of the heat pipe body, so that the heat pipe body is fully passivated and the passivation quality of the heat pipe body is enhanced. After the passivation treatment is completed, take out the heat pipe body and perform post-treatment to obtain a heat pipe body with a passivation film attached. In this way, the passivation quality of the heat pipe body can be improved, a uniform, dense and complete passivation film can be formed on the inner wall surface of the heat pipe body, the corrosion resistance and reliability of the heat pipe can be improved, and the heat dissipation performance of the electronic device can be improved.

[0012] In a possible implementation manner, the strong oxidant includes one of permanganate, persulfate, dichromate, peroxide, chlorate, and hypochlorite.

[0013] Permanganate, persulfate, dichromate, peroxide, chlorate, and hypochlorite all have strong oxidizing properties, which can fully oxidize the wall surface of the heat pipe body, form a good foundation for the subsequent passivation treatment of the heat pipe body, and form a uniform and dense passivation film on the wall surface of the heat pipe body.

[0014] In a possible implementation manner, the concentration of the strong oxidant in the passivation solution is 0.01wt%-15wt%.

[0015] By controlling the concentration of the strong oxidant in the passivation solution between 0.01wt%-15wt%, so that the passivation solution contains enough strong oxidant, the oxidation effect of the passivation solution can be ensured, and the wall surface of the heat pipe body can be fully oxidized.

[0016] In a possible implementation manner, the concentration of the strong oxidant in the passivation solution is 0.1wt%-5wt%.

[0017] By controlling the concentration of the strong oxidant in the passivation solution between 0.1wt%-5wt%, the content of the strong oxidant can be controlled within a suitable range. On the basis of ensuring that the wall surface of the heat pipe body is fully oxidized, over-oxidation of the wall surface of the heat pipe body is prevented, and the structural strength and reliability of the heat pipe body are ensured.

[0018] In a possible implementation manner, injecting the passivation solution into at least the cavity of the heat pipe body includes:

[0019] Immerse the heat pipe body in the passivation solution so that the passivation solution enters the cavity of the heat pipe body.

[0020] By immersing the heat pipe body in the passivation solution, the passivation solution can flow into the cavity of the heat pipe body. At the same time, the outer wall surface of the heat pipe body is also immersed in the passivation solution. In this way, on the basis that the inner wall surface of the heat pipe body is fully oxidized by the passivation solution, the outer wall surface of the heat pipe body is also fully oxidized by the passivation solution. Uniform and dense passivation films can be formed on both the inner wall surface and the outer wall surface of the heat pipe body, which can improve the overall corrosion resistance of the heat pipe body, making the heat pipe more reliable and having a longer service life.

[0021] In a possible implementation, the pressure-bearing furnace has a sealed furnace cavity.

[0022] By setting the sealed furnace cavity, during the working process, the furnace cavity of the pressure-bearing furnace is isolated from the external environment. In this way, the pressure inside the pressure-bearing furnace can be maintained at >0.1 Mpa, and the gas environment inside the pressure-bearing furnace can also be kept stable to ensure the passivation effect of the heat pipe body.

[0023] In a possible implementation, the gas filled in the pressure-bearing furnace includes one of air, oxygen, nitrogen, and oxygen-nitrogen mixture.

[0024] By performing passivation treatment on the heat pipe body in a gas environment of air, oxygen, nitrogen, or oxygen-nitrogen mixture, a uniform and dense passivation film can be formed on the surface of the heat pipe body to meet the corrosion resistance requirements of the heat pipe body, ensure the stability of the working performance of the heat pipe, and improve the reliability of the heat pipe.

[0025] In a possible implementation, the preset temperature is 100°C - 600°C.

[0026] By setting the preset temperature between 100°C - 600°C, the temperature inside the pressure-bearing furnace is maintained within a suitable range, which can fully and completely passivate the heat pipe body, facilitating the formation of a uniform, dense, and complete passivation film on the wall surface of the heat pipe body.

[0027] In a possible implementation, the preset temperature is 250°C - 400°C.

[0028] In a possible implementation, the predetermined time is 10 h - 100 h.

[0029] By controlling the predetermined time between 10 h - 100 h, the wall surface of the heat pipe body can be fully and completely passivated, ensuring the passivation effect of the heat pipe body, so as to form a uniform and dense passivation film on the wall surface of the heat pipe body and improve the reliability of the heat pipe body.

[0030] In a possible implementation, the predetermined time is 50 h - 100 h.

[0031] In a possible implementation, post-treatment is performed on the heat pipe body, including:

[0032] Cleaning the cavity of the heat pipe body with deionized water;

[0033] Performing a drying treatment on the heat pipe body to obtain a heat pipe body with a passivation film attached.

[0034] In a possible implementation, performing a drying treatment on the heat pipe body includes:

[0035] Performing a drying treatment on the heat pipe in a vacuum environment.

[0036] By performing a drying treatment on the heat pipe body in a vacuum environment, it is possible to prevent the passivation film on the heat pipe body with a passivation film from denaturing during drying in an oxygen-containing atmosphere, thereby improving the stability and reliability of the passivation film and improving the drying efficiency.

[0037] In a possible implementation, performing a drying treatment on the heat pipe body includes:

[0038] When performing the drying treatment, the drying temperature is 50°C - 90°C, and the drying time is 1h - 24h.

[0039] On the basis of being in a vacuum environment, by controlling the drying temperature between 50°C - 90°C and the drying time between 1h - 24h, the drying efficiency of the heat pipe body can be improved, and it can be ensured that the heat pipe body is completely dried.

[0040] In a possible implementation, performing a drying treatment on the heat pipe body includes:

[0041] When performing the drying treatment, the drying temperature is 60°C - 90°C, and the drying time is 2h - 8h.

[0042] In a possible implementation, obtaining the heat pipe body includes:

[0043] Forming an upper cover plate and a lower cover plate by processing a metal material;

[0044] Welding the upper cover plate and the lower cover plate to form the heat pipe body.

[0045] In a possible implementation, the metal material for forming the upper cover plate and the lower cover plate includes one of titanium alloy, stainless steel, and titanium metal composite plate.

[0046] Using one of titanium alloy, stainless steel, and titanium metal composite plate as the metal material to process the upper cover plate and the lower cover plate. These metal materials have low density and high strength, which is beneficial to reducing the overall thickness of the heat pipe body and meeting the requirements of the thinning of electronic devices. Moreover, these metal materials have good corrosion resistance and meet the working requirements of the heat pipe.

[0047] In a possible implementation, after obtaining the heat pipe body with a passivation film attached, the following steps are further included:

[0048] Inject liquid into the cavity of the heat pipe body and evacuate it;

[0049] Seal and shape the heat pipe body to obtain a heat pipe.

[0050] The second aspect of the present application provides a heat pipe manufactured by the manufacturing method described above. The heat pipe includes a heat pipe body and a coolant, and the coolant is located in the cavity of the heat pipe body;

[0051] Among them, a passivation film is attached to the wall surface of the heat pipe body.

[0052] The heat pipe provided by the present application includes a heat pipe body and a coolant injected into the cavity of the heat pipe body, and the heat pipe is manufactured by the aforementioned manufacturing method. Since a uniform, dense and complete passivation film is attached to the inner wall surface of the heat pipe body, the corrosion resistance and reliability of the heat pipe can be improved, and the heat dissipation performance of the electronic device can be enhanced.

[0053] In a possible implementation, the total thickness of the heat pipe ≤ 0.8 mm.

[0054] In a possible implementation, the area of the heat pipe ≤ 150 cm 2 .

[0055] In a possible implementation, the thickness of the passivation film attached to the inner wall surface of the heat pipe body is 10 nm - 150 nm.

[0056] By attaching a passivation film with a certain thickness to the inner wall surface of the heat pipe body, it is ensured that the passivation film can reliably play an anti-corrosion role and fully protect the inner wall surface of the heat pipe body.

[0057] The third aspect of the present application provides an electronic device, including a housing assembly and the heat pipe described above, and the heat pipe is disposed in the housing assembly.

[0058] The electronic device provided by the present application includes a housing assembly and a heat pipe, and the heat pipe is disposed in the housing assembly. The heat pipe includes a heat pipe body and a coolant injected into the cavity of the heat pipe body, and the heat pipe is manufactured by the aforementioned manufacturing method. Since a uniform, dense and complete passivation film is attached to the inner wall surface of the heat pipe body, the corrosion resistance and reliability of the heat pipe can be improved, and the heat dissipation performance of the electronic device can be enhanced. Description of the Drawings

[0059] Figure 1 It is a schematic structural diagram of an electronic device provided by an embodiment of the present application;

[0060] Figure 2 For Figure 1 exploded view of the electronic device shown;

[0061] Figure 3 Schematic diagram of the structure of another electronic device provided by an embodiment of the present application;

[0062] Figure 4 For Figure 3 Schematic diagram of the structure of the electronic device in the unfolded state in;

[0063] Figure 5 For Figure 3 Schematic diagram of the structure of the electronic device in the folded state in;

[0064] Figure 6 For Figure 3 exploded view of the electronic device in;

[0065] Figure 7 Side view of the heat pipe provided by an embodiment of the present application;

[0066] Figure 8 Top view of the heat pipe provided by an embodiment of the present application;

[0067] Figure 9a For the cross-sectional view of the heat pipe provided by an embodiment of the present application along Figure 8 A-A in;

[0068] Figure 9b For the cross-sectional view of another heat pipe provided by an embodiment of the present application along Figure 8 A-A in;

[0069] Figure 10 Flow chart of the steps of the manufacturing method of the heat pipe provided by an embodiment of the present application.

[0070] Explanation of reference numerals:

[0071] 10 - Electronic device;

[0072] 100 - Display screen; 100a - Folding screen; 100b - Straight plate screen; 200 - Housing assembly; 300 - Circuit board; 400 - Battery; 500 - Camera; 600 - Heat pipe; 600a - Heat pipe body; 700 - Heat source;

[0073] 110 - First area; 120 - Second area; 130 - Bendable area; 210 - First housing; 220 - Second housing; 230 - Rotating shaft; 610 - Upper cover plate; 620 - Lower cover plate; 630 - Capillary wick; 640 - Solder paste;

[0074] 201-middle frame; 202-back cover; 611-upper side plate; 612-top plate; 613-support column; 621-lower side plate; 622-bottom plate;

[0075] 2011-middle plate; 2012-frame; 6101-steam channel. DETAILED DESCRIPTION

[0076] The terms used in the implementation section of this application are only used to explain the specific embodiments of this application and are not intended to limit this application.

[0077] The embodiment of the present application provides an electronic device, which can be a consumer electronic product. Exemplarily, the electronic device includes but is not limited to a mobile phone, a portable android device (PAD), a notebook computer, a laptop computer, a netbook, an ultra-mobile personal computer (UMPC), a walkie-talkie, a POS (Point of sales) machine, a personal digital assistant (PDA), a multimedia player, an e-book reader, a vehicle-mounted device, a wearable device, a virtual reality (VR) device, an augmented reality (AR) device, etc. Among them, the wearable device includes but is not limited to a smart bracelet, a smart watch, a smart head-mounted display, smart glasses, etc.

[0078] Figure 1 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application. Figure 1 As shown, taking the electronic device 10 as a bar-type electronic device as an example, for example, the electronic device 10 is a bar-type mobile phone, the electronic device 10 may include a display screen 100 and a housing assembly 200. One side surface of the display screen 100 is used to display image information, and the side surface of the display screen 100 is usually defined as its front side, and the other side surface opposite to its front side is its back side. The housing assembly 200 is arranged around the side and back side of the display screen 100 to support and fix the display screen 100 and provide protection. The front side of the display screen 100 is exposed outside the housing assembly 200, so that the user can view the content displayed on the display screen 100 or perform input operations on the electronic device 10.

[0079] Taking the straight-bar mobile phone shown in the figure as an example, the display screen 100 of the electronic device 10 can be a rigid screen, and the display screen 100 can be an LCD (Liquid Crystal Display) screen or an OLED (Organic Light-Emitting Diode) screen.

[0080] Figure 2 For Figure 1 the exploded view of the electronic device shown. Refer to Figure 2 As shown, taking the straight-bar electronic device as an example, the housing assembly 200 of the electronic device 10 can include a middle frame 201 and a rear cover 202. The middle frame 201 is connected between the display screen 100 and the rear cover 202. The display screen 100 is supported on one side surface of the middle frame 201, and the rear cover 202 is connected to the other side surface of the middle frame 201. Among them, the display screen 100 is usually integrally mounted on the middle frame 201 to ensure the strength and stability of the display screen 100 and meet the usage requirements of the display screen 100. The rear cover 202 is usually connected to the middle frame 201 in a lapped manner. The middle frame 201 and the rear cover 202 together enclose a receiving cavity, and components such as a circuit board 300, a battery 400, a camera 500, and a microphone (not shown in the figure) are installed in the receiving cavity.

[0081] The middle frame 201 can include a middle plate portion 2011 and a frame portion 2012. The middle plate portion 2011 is located between the display screen 100 and the rear cover 202 and is usually arranged parallel to the display screen 100 and the rear cover 202. The frame portion 2012 surrounds the periphery of the middle plate portion 2011. For example, the frame portion 2012 can extend perpendicularly to the plate surface of the middle plate portion 2011 to both sides of the middle plate portion 2011. Exemplarily, the frame portion 2012 and the middle plate portion 2011 can be an integrally formed structure.

[0082] Among them, the display screen 100 is usually mounted on the middle plate portion 2011 of the middle frame 201 in an integrally fitting manner. For example, the display screen 100 is integrally bonded to the middle plate portion 2011. Relying on the support of the middle plate portion 2011 for the display screen 100, the display screen 100 can be supported stably and firmly, enabling the display screen 100 to have sufficient strength and meet the usage requirements of the display screen 100 being frequently pressed. The frame portion 2012 surrounds the periphery of the display screen 100, forms protection for the side of the display screen 100, helps the display screen 100 resist risk scenarios such as collision and drop, and protects the display screen 100 from being damaged.

[0083] The edge of the rear cover 202 is connected to the frame portion 2012 of the middle frame 201. For example, the edge of the rear cover 202 is adhesively bonded to the frame portion 2012. There is a gap between the middle plate portion 2011 of the middle frame 201 and the rear cover 202, and this gap forms the accommodation cavity as described above to install components in the accommodation cavity between the middle plate portion 2011 of the middle frame 201 and the rear cover 202.

[0084] Figure 3 FIG. is a schematic structural diagram of another electronic device provided by an embodiment of the present application; Figure 4 is Figure 3 a schematic structural diagram of the electronic device in FIG. when in the unfolded state; Figure 5 is Figure 3 a schematic structural diagram of the electronic device in FIG. when in the folded state.

[0085] Referring to Figures 3 to 5 As shown, taking the electronic device 10 as a foldable electronic device as an example, for example, the electronic device 10 is a folding mobile phone. The electronic device 10 may include at least two parts that can rotate relative to each other. In different usage scenarios, the electronic device 10 may have different usage states. In this embodiment, taking the foldable electronic device as the electronic device 10 that can be folded once as an example, the electronic device 10 includes two parts that can rotate relative to each other. By the relative rotation of the two parts, the usage state of the electronic device 10 is changed.

[0086] Among them, the two parts of the electronic device 10 can rotate relative to each other along the Figure 3 arrow direction shown in FIG., and when the two parts rotate to overlap each other, the electronic device 10 is in the Figure 4 folded state shown in FIG. At this time, the volume of the electronic device 10 is small and convenient to carry; the two parts of the electronic device 10 can also rotate relative to each other along the direction opposite to the Figure 3 arrow direction in FIG., and when the two parts rotate to be coplanar, the electronic device 10 is in the Figure 5 unfolded state shown in FIG. The unfolding angle α of the electronic device 10 is, for example, 180°. At this time, the electronic device 10 can achieve a large-screen display; in some cases, the electronic device 10 can also be maintained in a semi-unfolded state (see Figure 3 shown in FIG.), at this time, the electronic device 10 hovers at an angle between the unfolded state and the folded state. Exemplarily, the hovering angle β of the electronic device 10 can be 120°, 130°, 140° or 150°, etc.

[0087] It should be noted that a slight deviation is allowed for the angles illustrated in this embodiment. For example, when the unfolding angle α of the electronic device 10 is 180°, it means that the unfolding angle α can be 180°, or approximately 180°, such as 170°, 175°, 185°, 190°, etc. The same understanding can be applied to the angles illustrated hereinafter.

[0088] In addition, in addition to the electronic device 10 that can be folded once, the electronic device 10 can also be an electronic device 10 that can be folded more than twice. At this time, the electronic device 10 can include a plurality of parts that are rotatably connected in sequence. Two adjacent parts can be relatively close to each other to be folded into a folded state, and two adjacent parts can also be relatively far away from each other to be unfolded into an unfolded state.

[0089] Figure 6 For Figure 3 the exploded view of the electronic device in Figure 6 As shown in the figure, for the foldable electronic device, the electronic device 10 can also include a display screen 100 and a housing assembly 200. The front of the display screen 100 is used to display image information. The housing assembly 200 surrounds the periphery and the back of the display screen 100, and is used to support and fix the display screen 100 and provide protection, which will not be elaborated here.

[0090] Among them, the display screen 100 of the foldable electronic device can include a foldable screen 100a. The foldable screen 100a can include a first area 110, a second area 120, and a bendable area 130. The bendable area 130 is located between the first area 110 and the second area 120. During the use of the electronic device 10, the first area 110 and the second area 120 always remain in a flat state, while the bendable area 130 can be bent to change the included angle between the first area 110 and the second area 120, so that the foldable screen 100a folds or unfolds with the movement of the housing assembly 200, realizing the switching of the electronic device 10 between the folded state and the unfolded state.

[0091] Exemplarily, in the foldable screen 100a, at least the bendable area 130 is made of a flexible material so that the bendable area 130 can be bent. The first area 110 and the second area 120 can be made of a flexible material, can be made of a rigid material, or can be partially made of a rigid material and partially made of a flexible material. This embodiment does not limit this.

[0092] The foldable screen 100a includes, but is not limited to, an organic light-emitting diode (OLED) display screen, an active-matrix organic light-emitting diode (AMOLED) display screen, a mini organic light-emitting diode display screen, a micro organic light-emitting diode display screen, a micro organic light-emitting diode display screen, or a quantum dot light emitting diodes (QLED) display screen, etc.

[0093] Among them, as shown in Figure 4 and Figure 6 , when the foldable screen 100a is in the folded state, the first region 110 and the second region 120 are stacked relative to each other, and the bendable region 130 is in a bent state. The bending angle of the bendable region 130 is, for example, 180°. At this time, the volume of the electronic device 10 is small, which is convenient for carrying and storing. As shown in Figure 5 and Figure 6 , when the foldable screen 100a is in the unfolded state, the first region 110 and the second region 120 are in an unfolded state of being relatively far apart, the bendable region 130 is in a flattened state without bending, and the first region 110, the second region 120, and the bendable region 130 face the same direction and are in a coplanar state. At this time, the included angle between the first region 110 and the second region 120 is 180°, and the foldable screen 100a can achieve large-screen display, bringing a better user experience.

[0094] It should be noted that in the figure, the foldable electronic device is an inward-foldable electronic device. When the electronic device 10 is in the folded state, the first region 110 and the second region 120 of the foldable screen 100a are relatively attached, and the housing assembly 200 is arranged around the foldable screen 100a, which can prevent the foldable screen 100a from being scratched by hard objects. Refer to Figure 3 or Figure 4 . If the inward-foldable electronic device needs to implement a display function in the folded state, a straight screen 100b can be added to the back of the housing assembly 200. When the electronic device 10 is in the folded state, the display function is realized by relying on the straight screen 100b.

[0095] In other words, the display screen 100 of the foldable electronic device may include a folding screen 100a and a straight screen 100b. The folding screen 100a may be mounted on the front of the housing assembly 200. As the housing assembly 200 moves, the folding screen 100a may switch between a folded state and an unfolded state. When the electronic device 10 is in the folded state, the folding screen 100a is not visible from the outside. The straight screen 100b may be mounted on the back of the housing assembly 200, and the straight screen 100b displays when the electronic device 10 is in the folded state.

[0096] In other examples, the foldable electronic device may also be an outward-foldable electronic device. When the electronic device 10 is in the folded state, the first region 110 and the second region 120 of the folding screen 100a face away from each other, the housing assembly 200 is located between the first region 110 and the second region 120, and the folding screen 100a surrounds the housing assembly 200 and is visible to the user. When the outward-foldable electronic device is in the folded state, the folding screen 100a is exposed, and the display function can be realized by using the folding screen 100a. Therefore, there is no need to additionally add a straight screen 100b to the back of the housing to realize the display function of the electronic device 10 in the folded state.

[0097] In addition, as shown in combination with Figure 3 and Figure 6 In some embodiments, the foldable electronic device, especially the inward-foldable electronic device, can rely on the damping force provided by the housing assembly 200 to make the electronic device 10 hover at a semi-unfolded state between the unfolded state and the folded state. At this time, the folding screen 100a stays at the semi-unfolded state with the housing assembly 200, the bendable region 130 of the folding screen 100a is also in a bent state, and the bending degree of the bendable region 130 is less than that in the folded state, and the first region 110 and the second region 120 of the folding screen 100a are inclined relative to each other. Taking the hovering angles of the electronic device 10 as 120°, 130°, 140°, or 150°, etc. as examples, correspondingly, the included angle between the first region 110 and the second region 120 may be 120°, 130°, 140°, or 150°, etc.

[0098] For the foldable electronic device, in addition to supporting and fixing the display screen 100, the housing assembly 200 also needs to drive the folding screen 100a to switch between the folded state and the unfolded state. In this regard, as shown in reference to Figure 6 The housing assembly 200 of the foldable electronic device may include a first housing 210, a second housing 220, and a rotating shaft 230. The rotating shaft 230 is connected between the first housing 210 and the second housing 220, and the first housing 210 and the second housing 220 are rotatably connected through the rotating shaft 230, so as to realize the relative rotation between the first housing 210 and the second housing 220.

[0099] Among them, the first housing 210 supports and fixes the first area 110 of the folding screen 100a, and the second housing 220 supports and fixes the second area 120 of the folding screen 100a. In other words, the first area 110 of the folding screen 100a is fixedly connected to the first housing 210, and the second area 120 of the folding screen 100a is fixedly connected to the second housing 220. The bendable area 130 of the folding screen 100a is arranged corresponding to the rotating shaft 230. When the rotating shaft 230 drives the first housing 210 and the second housing 220 to rotate relative to each other, the orientations of the first area 110 and the second area 120 of the folding screen 100a change accordingly, and the bendable area 130 of the folding screen 100a bends or flattens as the orientations of the first area 110 and the second area 120 change.

[0100] The rotating shaft 230 drives the first housing 210 and the second housing 220 to rotate relative to each other, so that the electronic device 10 switches between the folded state and the unfolded state. Among them, the first housing 210 and the second housing 220 can rotate towards each other until they are stacked relative to each other. At this time, the housing assembly 200 is in the folded state, and the folding screen 100a is in the folded state as the housing assembly 200 folds, as Figure 4 shown. The first housing 210 and the second housing 220 can rotate away from each other until they are coplanar. At this time, the housing assembly 200 is in the unfolded state, and the folding screen 100a is in the unfolded state as the housing assembly 200 unfolds, as Figure 5 shown.

[0101] Exemplarily, the first housing 210 may have a support surface facing the first area 110 of the folding screen 100a, and the first area 110 of the folding screen 100a is mounted on the support surface of the first housing 210. For example, the first area 110 of the folding screen 100a is bonded to the support surface of the first housing 210. Similarly, the second housing 220 may have a support surface facing the second area 120 of the folding screen 100a, and the second area 120 of the folding screen 100a is mounted on the support surface of the second housing 220. For example, the second area 120 of the folding screen 100a is bonded to the support surface of the second housing 220.

[0102] In addition, both the first housing 210 and the second housing 220 may have a receiving cavity for installing some functional components of the electronic device 10. For example, the receiving cavity is used to install components such as a circuit board 300, a battery 400, a camera 500, a microphone (not shown in the figure), etc. Exemplarily, a circuit board 300 may be provided in both the first housing 210 and the second housing 220 to achieve electrical connection between the components in the two housings; the battery 400 for powering the components may be provided only in the first housing 210 or the second housing 220, or batteries 400 may be provided in both the first housing 210 and the second housing 220; as for other components such as the camera 500 and the microphone, they may be centrally provided in the first housing 210 or the second housing 220, or some components may be provided in the first housing 210 and some components may be provided in the second housing 220.

[0103] Continuing to refer to Figure 6 , in the housing assembly 200 of the foldable electronic device, both the first housing 210 and the second housing 220 may include a middle frame 201, and the first region 110 and the second region 120 of the folding screen 100a may be supported on the front of the corresponding middle frame 201. Among them, for an outward-foldable electronic device or an inward-foldable electronic device without an additional straight screen 100b, both the first housing 210 and the second housing 220 of the electronic device 10 may further include a rear cover 202, and the rear cover 202 is connected to the surface of the middle frame 201 facing away from the folding screen 100a; for an inward-foldable electronic device with an additional straight screen 100b, one of the first housing 210 and the second housing 220 may not include a rear cover 202, but instead a straight screen 100b is installed on the back of the middle frame 201 as an alternative.

[0104] In the first housing 210 and the second housing 220, the middle frame 201 and the rear cover 202 (or the straight screen 100b) together enclose a receiving cavity for installing the aforementioned circuit board 300, battery 400, camera 500, microphone and other components.

[0105] A vapor chamber (VC) is usually provided in the housing assembly 200 of the electronic device 10 to dissipate heat from some functional components in the electronic device 10. Currently, the main structure of the most commonly used vapor chamber on the electronic device 10 is made of copper alloy. However, due to the relatively high density of the copper alloy, it is difficult to further meet the thinning requirements of the vapor chamber, which in turn limits the thinning of the electronic device 10.

[0106] In this way, it is necessary to use other metals with lower density and excellent mechanical properties as the main material of the heat pipe. And, based on the heat dissipation principle of the heat pipe, during the operation of the heat pipe, the coolant in its cavity will contact the wall of the cavity. Therefore, this metal should also have strong corrosion resistance. Metals such as stainless steel, titanium alloy and their composite materials, due to having a lower density and higher strength than copper alloy, and at the same time, the passivation film existing on the surface of these metals can improve their corrosion resistance, can meet the requirements for further thinning of the heat pipe.

[0107] However, in the natural state, the passivation film on the surface of metals such as stainless steel, titanium alloy and their composite materials is very thin, has poor compactness and is uneven. When in a liquid and vapor environment for a long time, the metal is likely to react with the liquid and be corroded. Furthermore, it causes the performance of the heat pipe to decay during use, affecting the heat dissipation performance of the electronic device.

[0108] In view of this, the embodiment of the present application improves the manufacturing process of the heat pipe. After obtaining the heat pipe body, by using a passivation solution containing a strong oxidant, at least injecting the passivation solution into the cavity of the heat pipe body can promote the full oxidation of the inner wall surface of the heat pipe body, which helps to improve the passivation quality of the heat pipe body. Then, place the heat pipe body in a pressure furnace, keep the heat pipe body at a preset temperature for a predetermined time to perform passivation treatment on the heat pipe body, so as to strengthen the reaction process of the wall surface of the heat pipe body, make the heat pipe body fully passivated, and enhance the passivation quality of the heat pipe body. After the passivation treatment is completed, take out the heat pipe body and perform post-treatment to obtain the heat pipe body with a passivation film attached. In this way, it can be ensured that the heat pipe body is fully passivated, and a uniform, dense and complete passivation film can be formed on the inner wall surface of the heat pipe body, which can improve the corrosion resistance and reliability of the heat pipe and enhance the heat dissipation performance of the electronic device.

[0109] The heat pipe and its manufacturing method provided by the embodiment of the present application will be described in detail below.

[0110] Figure 7 It is a side view of the heat pipe provided by the embodiment of the present application. Figure 8 It is a top view of the heat pipe provided by the embodiment of the present application. Figure 9a It is a cross-sectional view of a heat pipe provided by the embodiment of the present application along Figure 8 A-A therein. Figure 9b It is a cross-sectional view of another heat pipe provided by the embodiment of the present application along Figure 8 A-A therein.

[0111] Refer to Figure 7 、 Figure 8 、 Figure 9a 、 Figure 9bAs shown in any of them, the vapor chamber 600 provided in the embodiments of the present application can be applied to the aforementioned small and thin electronic devices 10 such as mobile phones, wearable devices, netbooks, and laptop computers. The vapor chamber 600 has a small thickness and a small area, and the overall volume of the vapor chamber 600 is small.

[0112] Specifically, the total thickness of the vapor chamber 600 can be 0.1 mm - 1 mm, or rather, the total thickness of the vapor chamber 600 can be between 0.1 mm and 1 mm. Exemplarily, the total thickness of the vapor chamber 600 can be ≤ 0.8 mm. For example, the total thickness of the vapor chamber 600 can be 0.40 mm, 0.45 mm, 0.50 mm, 0.55 mm, 0.60 mm, 0.65 mm, 0.70 mm, 0.75 mm, etc.

[0113] Taking the electronic device 10 as a mobile phone as an example, the area of the vapor chamber 600 can be smaller than the area of the mobile phone. Among them, taking a straight - bar mobile phone as an example, the vapor chamber 600 can be smaller than the area of the straight - bar mobile phone; taking a folding mobile phone as an example, the vapor chamber 600 can be smaller than the area of a relatively rotatable part in the folding mobile phone. Exemplarily, the area of the vapor chamber 600 can be ≤ 150 cm 2 For example, the area of the vapor chamber 600 can be ≤ 100 cm 2 For example, the area of the vapor chamber 600 is 30 cm 2 、35 cm 2 、40 cm 2 、45 cm 2 、50 cm 2 、55 cm 2 、60 cm 2 、65 cm 2 、70 cm 2 、75 cm 2 and so on.

[0114] Referring to Figure 7 or Figure 8 As shown, the outer surface of the vapor chamber 600 and the heat source 700 provided on the outer surface of the vapor chamber 600 are schematically shown in the figure. The heat source 700 can be considered as a power - consuming device that generates heat in the electronic device 10. For example, the heat source 700 is a device such as a processor, an image processor, a memory, etc. The vapor chamber 600 can be attached to the surface of the heat source 700. The vapor chamber 600 is used to absorb the heat of the heat source 700 and dissipate the heat to maintain the working performance of the power - consuming device.

[0115] Referring to Figure 7 As shown, the thickness of the vapor chamber 600 is very small, similar to a sheet - like structure. The vapor chamber 600 occupies a small space and is suitable for being arranged in the thin - type electronic device 10 to facilitate the heat dissipation of the power - consuming device in the electronic device 10. Combining Figure 7 andFigure 8 As shown, the heat source 700 is located on one surface of the heat pipe 600 in the thickness direction. The heat of the heat source 700 is transferred from this side wall surface of the heat pipe 600 to the heat pipe 600. The heat pipe 600 absorbs the heat of the heat source 700 and dissipates the heat.

[0116] Among them, referring to Figure 7 or Figure 8 As shown, the heat source 700 is usually arranged near one end of the heat pipe 600. Taking the heat pipe 600 as a rectangle as an example, the heat source 700 can be arranged near one end of the heat pipe 600 in the length direction ( Figure 7 or Figure 8 the X direction shown in

[0117] The heat pipe 600 has a cavity inside, and a coolant is filled in the cavity. The coolant is, for example, pure water. After the heat of the heat source 700 is transferred to the heat pipe 600, through the heat absorption and heat release of the coolant, the state of the coolant changes, realizing heat conversion to achieve the heat dissipation function of the heat pipe 600. Among them, the planar size of the heat pipe 600 is usually larger than the corresponding size of the heat source 700. By arranging the heat source 700 near one end of the heat pipe 600, enough flow space can be reserved for the coolant to realize the state change of the coolant.

[0118] For the heat pipe 600, the end near the heat source 700 is equivalent to the evaporation end of the heat pipe 600, and the end far from the heat source 700 is equivalent to the condensation end of the heat pipe 600. The heat source 700 transfers heat to the evaporation end of the heat pipe 600. The coolant (such as pure water) at the evaporation end absorbs heat and vaporizes into steam (such as water vapor). The steam accumulates at the evaporation end, increasing the air pressure at the evaporation end. Under the action of the gas pressure, the steam flows from the high-pressure area (evaporation end) to the low-pressure area (condensation end). When the steam flows and touches the inner wall of the heat pipe 600 (with a lower temperature), condensation will occur, releasing heat and liquefying into a liquid. The liquid flows back to the evaporation end along the inner wall of the heat pipe 600, and so on in a cycle to dissipate the heat of the heat source 700.

[0119] Referring to Figure 9a or Figure 9b As shown, the heat pipe 600 includes a heat pipe body 600a, and the heat pipe body 600a is the main structure of the heat pipe 600. The heat pipe body 600a has a cavity, and the aforementioned coolant is located in the cavity of the heat pipe body 600a. Equivalently, the heat pipe body 600a and the coolant together form the heat pipe 600.

[0120] Among them, the heat pipe body 600a includes an upper cover plate 610 and a lower cover plate 620. The upper cover plate 610 and the lower cover plate 620 are connected together to form the outer shell of the heat pipe 600. Among them, the upper cover plate 610 may include an upper side plate portion 611 and a top plate portion 612. The upper side plate portion 611 surrounds the edge of the top plate portion 612, and the upper side plate portion 611 and the top plate portion 612 may be an integrally formed structure. The lower cover plate 620 may include a lower side plate portion 621 and a bottom plate portion 622. The lower side plate portion 621 surrounds the edge of the bottom plate portion 622, and the lower side plate portion 621 and the bottom plate portion 622 may be an integrally formed structure. The upper side plate portion 611 of the upper cover plate 610 and the lower side plate portion 621 of the lower cover plate 620 are connected together, and the upper cover plate 610 and the lower cover plate 620 jointly enclose a cavity.

[0121] One of the upper cover plate 610 and the lower cover plate 620 corresponds to the heat source 700. For example, the heat source 700 may be attached to the outer wall surface of one of the upper cover plate 610 and the lower cover plate 620. Hereinafter, taking the lower cover plate 620 corresponding to the heat source 700 as an example, the heat source 700 may be attached to the outer wall surface of the bottom plate portion 622 of the lower cover plate 620.

[0122] Continue to refer to Figure 9a or Figure 9b As shown, the upper cover plate 610 of the heat pipe body 600a may further be provided with a plurality of support columns 613. Each support column 613 may be connected to the inner wall surface of the top plate portion 612 in the upper cover plate 610. For example, each support column 613 is integrally formed on the inner wall surface of the top plate portion 612. Each support column 613 extends downward to the lower cover plate 620, and each support column 613 may extend from the evaporation end of the heat pipe 600 to the condensation end of the heat pipe 600.

[0123] A steam channel 6101 is formed between adjacent support columns 613. The steam channel 6101 extends from the evaporation end of the heat pipe 600 to the condensation end of the heat pipe 600. Steam can flow along the steam channel 6101 to guide the steam to flow smoothly towards the condensation end of the heat pipe 600. On the other hand, the setting of the support columns 613 can also enhance the structural strength of the upper cover plate 610, and further enhance the overall structural strength and reliability of the heat pipe body 600a.

[0124] Refer to Figure 9aAs shown, in some embodiments, the heat pipe body 600a further includes a wick 630. The wick 630 is disposed in a cavity formed by enclosing the upper cover plate 610 and the lower cover plate 620. The wick 630 adsorbs the coolant through capillary action so that the coolant can flow back to the evaporation end where the heat source 700 is located. The wick 630 is disposed corresponding to the heat source 700. The wick 630 can be connected to the lower cover plate 620. For example, the wick 630 is mounted on the inner wall surface of the bottom plate portion 622 of the lower cover plate 620. The wick 630 can cover the entire area of the bottom plate portion 622 so that the coolant in any area in the cavity can be adsorbed by the wick 630, ensuring that the heat pipe 600 can work stably for a long time and guaranteeing the heat dissipation effect of the heat pipe 600.

[0125] When a wick 630 is disposed in the cavity of the heat pipe body 600a, the support posts 613 on the upper cover plate 610 can extend to abut against the surface of the wick 630. Relying on the pressure of the support posts 613 on the wick 630, the wick 630 can be helped to be fixed. And, under the combined action of the support posts 613 and the wick 630, the overall structural strength and reliability of the heat pipe body 600a can be enhanced.

[0126] Referring to Figure 9b As shown, in other embodiments, a wick 630 may not be disposed in the cavity of the heat pipe body 600a, and the support posts 613 on the upper cover plate 610 can be extended to abut against the bottom plate portion 622 of the lower cover plate 620. By processing a liquid absorption structure (not shown in the figure) on these support posts 613, the liquid absorption structure is, for example, a liquid absorption groove or a liquid absorption texture provided on the side wall of the support post 613, and the coolant is drained to the evaporation end where the heat source 700 is located by relying on the liquid absorption groove or the liquid absorption texture on the support post 613.

[0127] In other embodiments, on the basis of disposing a wick 630 in the cavity of the heat pipe body 600a, the support posts 613 on the upper cover plate 610 may also have liquid absorption grooves or liquid absorption textures. In other words, both a wick 630 is disposed in the cavity of the heat pipe body 600a and the support posts 613 have liquid absorption grooves (or liquid absorption textures). Relying on the combined action of the wick 630 and the liquid absorption grooves (or liquid absorption textures) on the support posts 613, the coolant is drained to the evaporation end where the heat source 700 is located.

[0128] Combined with Figures 7 to 9a (or Figure 9b) As shown, the working process of the vapor chamber 600 is as follows: The heat generated by the heat source 700 is conducted to the evaporation end of the vapor chamber 600. The coolant adsorbed inside the capillary wick 630 (or the coolant adsorbed in the liquid absorption structure of the support post 613, or the coolant attached to the inner wall surface of the lower cover plate 620) quickly absorbs this heat and vaporizes to turn into steam, and the steam moves into the steam channel 6101 of the upper cover plate 610 at the evaporation end. The steam accumulates in the steam channel 6101 at the evaporation end, increasing the air pressure at the evaporation end. Under the action of the air pressure, the steam flows along the steam channel 6101 towards the condensation end of the vapor chamber 600. During the flow of the steam, when it contacts the inner wall of the vapor chamber body 600a (such as the upper cover plate 610), the steam quickly condenses, releases heat and liquefies into a liquid. The liquid is adsorbed by the capillary wick 630 (or the liquid absorption grooves or liquid absorption textures on the support post 613) and flows back to the evaporation end of the vapor chamber 600, and this cycle repeats.

[0129] Among them, in the vapor chamber body 600a, both the upper cover plate 610 and the lower cover plate 620 are processed from metal materials. The metal materials for manufacturing the upper cover plate 610 and the lower cover plate 620 include but are not limited to one of titanium alloy, stainless steel, and titanium metal composite plates. For example, both the upper cover plate 610 and the lower cover plate 620 are processed from titanium alloy or stainless steel. These metal materials have low density and high strength, which is beneficial to reducing the overall thickness of the vapor chamber body 600a and meeting the requirement of the thin and light of the electronic device 10. Moreover, these metal materials have good corrosion resistance, and for the vapor chamber 600 that works in the process of continuous vaporization and condensation of the coolant for a long time, these metal materials better meet the working requirements of the vapor chamber 600.

[0130] Refer to Figure 9a or Figure 9b As shown, since both the upper cover plate 610 and the lower cover plate 620 are processed from metal materials, the upper cover plate 610 and the lower cover plate 620 can be connected by welding. Solder paste 640 can be provided between the upper side plate portion 611 of the upper cover plate 610 and the lower side plate portion 621 of the lower cover plate 620, and the upper cover plate 610 and the lower cover plate 620 are connected together through the solder paste 640. Exemplarily, the upper cover plate 610 and the lower cover plate 620 can be connected by laser welding process, or can also be connected by welding processes such as manual welding, resistance welding, brazing, diffusion welding, etc.

[0131] The capillary wick 630 can also be made of a metal material. For example, the capillary wick 630 is made of stainless steel and can have a dense mesh structure. The metal material has good stability and high reliability, which can meet the long-term use requirements of the heat pipe 600. Moreover, the metal material has good heat transfer performance and can quickly conduct heat to the coolant adsorbed therein. In addition, a metal material with good corrosion resistance can be selected to make the capillary wick 630, so as to reduce the corrosion of the coolant on the capillary wick 630 during long-term use, improve the reliability of the capillary wick 630, and extend the service life of the capillary wick 630.

[0132] In this embodiment, by passivating the heat pipe body 600a, a passivation film (not shown in the figure) is attached to at least part of the wall surface of the heat pipe body 600a. Among them, the passivation film is at least attached to the inner wall surfaces of the upper cover plate 610 and the lower cover plate 620. In other words, the passivation film is at least attached to the inner wall surface of the heat pipe body 600a. On this basis, the passivation film can also be attached to the surface of the capillary wick 630, and the passivation film can also be attached to the outer wall surfaces of the upper cover plate 610 and the lower cover plate 620. In other words, the passivation film can also be attached to the outer wall surface of the heat pipe body 600a.

[0133] By attaching a uniform and dense passivation film to the inner wall surface of the heat pipe body 600a, the passivation film completely covers the inner wall surface of the heat pipe 600. In this way, the passivation film attached to the inner wall surface of the heat pipe body 600a forms a complete protection for the inner wall surface of the heat pipe body 600a, which can enhance the corrosion resistance of the heat pipe body 600a, improve the reliability of the heat pipe body 600a, and extend the service life of the heat pipe body 600a. Ensure the performance stability of the heat pipe 600 during use, and further improve the heat dissipation performance of the electronic device 10.

[0134] Among them, the thickness of the passivation film attached to the inner wall surface of the heat pipe body 600a can be 10nm - 150nm. In other words, the thickness of the passivation film attached to the inner wall surface of the heat pipe body 600a can be between 10nm and 150nm. A passivation film with a certain thickness is attached to the inner wall surface of the heat pipe body 600a, which can ensure that the passivation film reliably plays an anti-corrosion role and provides sufficient protection for the inner wall surface of the heat pipe body 600a.

[0135] Exemplarily, the thickness of the passivation film attached to the inner wall surface of the heat pipe body 600a can be 20nm, 30nm, 40nm, 50nm, 60nm, 70nm, 80nm, 90nm, 100nm, 110nm, 120nm, 130nm, 140nm, etc.

[0136] Figure 10 It is a step flowchart of the manufacturing method of the heat pipe provided by the embodiment of the present application. Refer toFigure 10 As shown in Figure 10 , the manufacturing method of the heat pipe 600 provided by the embodiment of the present application is used to manufacture the aforementioned heat pipe 600. The manufacturing method includes the following steps:

[0137] S100. Obtain the heat pipe body.

[0138] First, obtain the heat pipe body 600a, and then perform passivation treatment on the heat pipe body 600a to form a passivation film on at least part of the wall surface of the heat pipe body 600a. Among them, a passivation film is formed at least on the inner wall surface of the heat pipe body 600a.

[0139] As shown in conjunction with Figure 9, obtaining the heat pipe body 600a may specifically include the following steps:

[0140] (1) Process the upper cover plate and the lower cover plate with metal materials.

[0141] First, provide a metal material, which includes but is not limited to the aforementioned titanium alloy, stainless steel, and titanium metal composite plate. Process the upper cover plate 610 and the lower cover plate 620 with this metal material.

[0142] Exemplarily, a flat plate can be provided as the initial plate of the upper cover plate 610 first, and then, through processes such as etching or stamping, part of the material of the initial plate is removed to form each support column 613, and then, the upper cover plate 610 is manufactured. Similarly, a flat plate can be provided as the initial plate of the lower cover plate 620 first, and then, through the bending process or stamping process, the prototype of the lower cover plate 620 is formed.

[0143] Among them, taking the heat pipe 600 shown in Figure 9a as an example, since the capillary wick 630 is an independent component, a separate capillary wick 630 needs to be provided to facilitate subsequent assembly to form the heat pipe body 600a. Taking the heat pipe 600 shown in Figure 9b as an example, after processing each support column 613 on the upper cover plate 610, a liquid absorption structure can be processed on the support column 613. For example, a liquid absorption groove or liquid absorption texture is processed on the support column 613 through an etching process as the liquid absorption structure on the support column.

[0144] Among them, in order to ensure the structural strength of the heat pipe body 600a and at the same time reduce the overall thickness of the heat pipe body 600a, so that the heat pipe 600 can meet the requirements of thinner and lighter electronic devices 10. In some embodiments, the thickness of the initial plate for manufacturing the lower cover 620 can be relatively large to ensure that the lower side plate portion 621 of the lower cover 620 has sufficient thickness. On this basis, the thickness of the bottom plate portion 622 of the lower cover 620 can be reduced. For example, a part of the thickness of the bottom plate portion 622 can be etched away to reduce the thickness of the bottom plate portion 622, and further reduce the overall thickness of the heat pipe body 600a.

[0145] It can be understood that after reducing the thickness of the bottom plate portion 622 of the lower cover 620, the heat transfer distance between the heat source 700 and the coolant in the capillary wick 630 is also reduced, which is beneficial to enhancing the heat transfer efficiency of the heat pipe 600, improving the heat dissipation efficiency of the heat pipe 600, and enhancing the heat dissipation performance of the heat pipe 600.

[0146] When a capillary wick 630 needs to be arranged in the cavity of the heat pipe body 600a, after the upper cover 610 and the lower cover 620 are processed and formed, then the capillary wick 630 is connected to the lower cover 620. For example, the capillary wick 630 can be welded to the lower cover 620, or the capillary wick 630 can be bonded to the lower cover 620, or the capillary wick 630 can be fixed to the lower cover 620 by using locking parts such as screws and rivets.

[0147] (2) Weld the upper cover and the lower cover to form the heat pipe body.

[0148] After that, the upper cover 610 and the lower cover 620 can be butt-connected to assemble into a complete heat pipe body 600a. For the upper cover 610 and the lower cover 620 made of metal materials, a welding method can be used to weld the upper side plate portion 611 of the upper cover 610 and the lower side plate portion 621 of the lower cover 620. For example, welding processes such as laser welding, manual welding, resistance welding, brazing, and diffusion welding can be used to connect the upper cover 610 and the lower cover 620 together.

[0149] After connecting the upper cover 610 and the lower cover 620, each support post 613 on the upper cover 610 can abut on the surface of the capillary wick 630 (or each support post 613 abuts on the bottom plate portion 622 of the lower cover 620) to form a plurality of parallel steam channels 6101. Among them, each steam channel 6101 can extend from the evaporation end of the heat pipe 600 to the condensation end of the heat pipe 600 to drain the steam in the heat pipe 600 through the steam channel 6101.

[0150] S200, provide a passivation solution containing a strong oxidant, and inject the passivation solution into at least the cavity of the heat pipe body.

[0151] It should be noted that for the heat pipe body 600a obtained above, a liquid injection port is reserved on the wall surface of the heat pipe body 600a, and the liquid injection port communicates with the cavity inside the heat pipe body 600a.

[0152] After obtaining the heat pipe body 600a, a passivation liquid containing a strong oxidant is provided and used for the heat pipe body 600a. Among them, the passivation liquid is at least injected into the cavity of the heat pipe body 600a. For example, the passivation liquid can be injected into the cavity of the heat pipe body 600a through the liquid injection port reserved on the wall surface of the heat pipe body 600a. In this way, the inner wall surface of the heat pipe body 600a can be fully oxidized by the passivation liquid containing a strong oxidant. When subsequent passivation treatment is performed on the heat pipe body 600a, the passivation quality of the heat pipe body 600a can be improved, which is beneficial to forming a uniform and dense passivation film on the inner wall surface of the heat pipe body 600a, so that the formed passivation film can completely cover the inner wall surface of the heat pipe body 600a.

[0153] In some embodiments, the passivation liquid can be injected into the cavity only through the liquid injection port on the heat pipe body 600a. In other words, the passivation liquid is only located in the cavity of the heat pipe body 600a, and the inner wall surface of the heat pipe body 600a is passivated by the passivation liquid. Based on the working principle of the heat pipe 600, during the working process of the heat pipe 600, the cavity of the heat pipe body 600a is in an environment where the coolant and steam constantly alternate, and the inner wall surface of the heat pipe body 600a is easily corroded. Therefore, only by fully oxidizing the inner wall surface of the heat pipe body 600a to ensure that a uniform, dense and complete passivation film can be formed on the inner wall surface of the heat pipe body 600a, the inner wall surface of the heat pipe body 600a can be protected from corrosion, the reliability of the heat pipe 600 can be improved, and the service life of the heat pipe 600 can be extended.

[0154] In other embodiments, on the basis of injecting the passivation liquid into the cavity of the heat pipe body 600a, the passivation liquid containing a strong oxidant can also be made to cover the outer wall surface of the heat pipe body 600a, so as to passivate the outer wall surface of the heat pipe body 600a through the passivation liquid. In this way, after subsequent passivation treatment of the heat pipe body 600a, a uniform and dense passivation film can also be formed on the outer wall surface of the heat pipe body 600a, which can enhance the corrosion resistance of the outer wall surface of the heat pipe body 600a. In this way, the overall corrosion resistance of the heat pipe body 600a is improved, and the heat pipe 600 has higher reliability and longer service life.

[0155] Exemplarily, the heat pipe body 600a can be immersed in a passivation solution containing a strong oxidant. In this way, the passivation solution can enter the cavity of the heat pipe body 600a through the liquid injection port on the heat pipe body 600a, and the outer wall surface of the heat pipe body 600a is also immersed in the passivation solution. Alternatively, on the basis of injecting the passivation solution into the cavity of the heat pipe body 600a, the passivation solution can also be sprayed on the outer wall surface of the heat pipe body 600a so that the passivation solution covers the outer wall surface of the heat pipe body 600a.

[0156] It can be understood that when the capillary wick 630 is disposed in the cavity of the heat pipe body 600a, by injecting a passivation solution containing a strong oxidant into the cavity of the heat pipe body 600a, the capillary wick 630 located in the cavity of the heat pipe body 600a will also come into contact with the passivation solution. Therefore, the passivation solution will also oxidize the capillary wick 630. Furthermore, after the subsequent passivation treatment of the heat pipe body 600a, a passivation film will also be formed on the surface of the capillary wick 630, which is also beneficial to enhancing the corrosion resistance of the capillary wick 630.

[0157] In this embodiment, the strong oxidant contained in the passivation solution can include one of permanganate, persulfate, dichromate, peroxide, chlorate, and hypochlorite. These components all have strong oxidizing properties, which can fully oxidize the wall surface of the heat pipe body 600a to form a good foundation for the subsequent passivation treatment of the heat pipe body 600a, and a uniform and dense passivation film can be formed on the wall surface of the heat pipe body 600a.

[0158] Among them, the concentration of the strong oxidant in the passivation solution can be 0.01 weight percent (wt%) - 15 weight percent (wt%), or rather, the concentration of the strong oxidant in the passivation solution is between 0.01 wt% and 15 wt%. In this way, the passivation solution contains enough strong oxidant to ensure the oxidation effect of the passivation solution, so that the wall surface of the heat pipe body 600a is fully oxidized.

[0159] Exemplarily, the concentration of the strong oxidant in the passivation solution can be 0.1 wt% - 5 wt% to control the content of the strong oxidant within a suitable range. On the basis of ensuring that the wall surface of the heat pipe body 600a is fully oxidized, it prevents the wall surface of the heat pipe body 600a from being over-oxidized, and ensures the structural strength and reliability of the heat pipe body 600a.

[0160] For example, the concentration of the strong oxidant in the passivation solution is 0.15 wt%, 0.20 wt%, 0.25 wt%, 0.30 wt%, 0.35 wt%, 0.40 wt%, 0.45 wt%, etc.

[0161] S300. Place the heat pipe body in a pressure-bearing furnace and perform passivation treatment at a preset temperature for a predetermined time. Wherein, the pressure in the pressure-bearing furnace > 0.1 Mpa.

[0162] After the wall surface of the heat pipe body 600a is fully oxidized by a passivation solution containing a strong oxidant, next, place the heat pipe body 600a in a pressure-bearing furnace and perform passivation treatment on the heat pipe body 600a at a preset temperature for a predetermined time. In other words, place the heat pipe body 600a in a pressure-bearing furnace, set the temperature in the pressure-bearing furnace to the preset temperature, and keep it warm for a predetermined time to perform passivation treatment on the heat pipe body 600a.

[0163] It should be understood that after the heat pipe body 600a is placed in the pressure-bearing furnace, there is still passivation solution in the cavity of the heat pipe body 600a, or rather, the heat pipe body 600a is placed in the pressure-bearing furnace together with the passivation solution in its cavity. Among them, the liquid injection port on the heat pipe body 600a is arranged upward in the pressure-bearing furnace (in the direction of gravity) so that the passivation solution can stably exist in the cavity of the heat pipe body 600a. During the passivation process of the heat pipe body 600a, under the action of high temperature, at least part of the passivation solution in the cavity of the heat pipe body 600a evaporates, which can also help the passivation solution to fully contact all parts of the inner wall surface of the heat pipe body 600a, strengthen the oxidation effect of the inner wall surface of the heat pipe body 600a, and enable the inner wall surface of the heat pipe body 600a to be fully oxidized.

[0164] In addition, when treating the heat pipe body 600a with a passivation solution containing a strong oxidant, when the outer wall surface of the heat pipe body 600a is also attached with passivation solution, after the heat pipe body 600a is placed in the pressure-bearing furnace, under the action of high temperature, the oxidation effect of the outer wall surface of the heat pipe body 600a can also be strengthened.

[0165] Among them, the atmosphere selected in the pressure-bearing furnace can include one of air, oxygen, nitrogen, and oxygen-nitrogen mixture. That is to say, the gas filled in the pressure-bearing furnace can include one of air, oxygen, nitrogen, and oxygen-nitrogen mixture. By performing passivation treatment on the heat pipe body 600a in a gas environment of air, oxygen, nitrogen, or oxygen-nitrogen mixture, a uniform and dense passivation film can be formed on the wall surface of the heat pipe body 600a to meet the corrosion resistance requirements of the heat pipe body 600a, ensure the stability of the working performance of the heat pipe 600, and improve the reliability of the heat pipe 600.

[0166] In this embodiment, the heat sink body 600a is placed in a pressure-bearing furnace for passivation treatment, and the pressure in the pressure-bearing furnace > 0.1 Mpa. In this way, the wall surface of the heat sink body 600a bears a certain air pressure, which can make the gas in the pressure-bearing furnace fully contact with the heat sink body 600a, improve the passivation efficiency of the heat sink body 600a, and enhance the passivation effect of the heat sink body 600a.

[0167] Exemplarily, the pressure-bearing furnace may have a sealed furnace cavity, that is to say, during the working process, the furnace cavity of the pressure-bearing furnace is isolated from the external environment. On the one hand, the sealed furnace cavity can maintain the pressure in the pressure-bearing furnace so that the pressure in the pressure-bearing furnace remains > 0.1 MPa; on the other hand, the sealed furnace cavity can keep the gas environment in the pressure-bearing furnace stable to ensure the passivation effect of the heat sink body 600a.

[0168] During the passivation treatment of the heat sink body 600a, the temperature in the pressure-bearing furnace can be maintained between 100°C and 600°C, that is to say, the preset temperature can be 100°C - 600°C. In this way, the temperature in the pressure-bearing furnace is maintained within a suitable range, which can make the heat sink body 600a fully and completely passivated, so as to form a uniform, dense and complete passivation film on the wall surface of the heat sink body 600a.

[0169] Exemplarily, the preset temperature can be 250°C - 400°C to control the temperature in the pressure-bearing furnace within a range more suitable for the passivation of the heat sink body 600a, which is more conducive to the passivation of the heat sink body 600a. On the basis of ensuring the passivation quality of the heat sink body 600a, the passivation efficiency of the heat sink body 600a is improved.

[0170] For example, the preset temperatures are 260°C, 270°C, 280°C, 290°C, 300°C, 310°C, 320°C, 330°C, 340°C, 350°C, 360°C, 370°C, 380°C, 390°C, etc.

[0171] The passivation time of the heat sink body 600a in the pressure-bearing furnace can be between 10h and 100h, that is to say, the predetermined time can be 10h - 100h. Specifically, the predetermined time can be set according to factors such as the materials of the upper cover 610 and the lower cover 620 of the heat sink body 600a, the types and concentrations of strong oxidants in the passivation solution, and the size of the heat sink body 600a, so that the wall surface of the heat sink body 600a is fully and completely passivated, ensuring the passivation effect of the heat sink body 600a and improving the working performance of the heat sink body 600a.

[0172] Exemplarily, the predetermined time can be 50h - 100h. In this way, the soaking plate body 600a has more sufficient passivation time in the pressure furnace, which can enhance the passivation effect of the wall surface of the soaking plate body 600a, so as to form a uniform and dense passivation film on the wall surface of the soaking plate body 600a. It also helps to increase the thickness of the passivation film formed on the wall surface of the soaking plate body 600a, enhance the reliability of the passivation film, and extend the service life of the soaking plate 600.

[0173] For example, the predetermined time is 55h, 60h, 65h, 70h, 75h, 80h, 85h, 90h, 95h, etc.

[0174] S400. Take out the soaking plate body and perform post-treatment on the soaking plate body to obtain a soaking plate body with a passivation film attached thereto.

[0175] After the passivation treatment of the soaking plate body 600a is completed, the temperature in the pressure furnace gradually decreases. The soaking plate body 600a can be cooled in the furnace to room temperature. Then, take out the soaking plate body 600a, pour out the passivation liquid in the cavity of the soaking plate body 600a, and perform post-treatment on the soaking plate body 600a to obtain a soaking plate body 600a with sufficient passivation. At this time, a passivation film is attached to the wall surface of the soaking plate body 600a.

[0176] Performing post-treatment on the soaking plate body 600a may specifically include the following steps:

[0177] (1) Clean the cavity of the soaking plate body with deionized water.

[0178] Since during the passivation treatment, the cavity of the soaking plate body 600a has a passivation liquid (containing a strong oxidant), therefore, after the passivation treatment is completed, it is necessary to clean the cavity of the soaking plate body 600a to remove the passivation liquid remaining in the cavity of the soaking plate body 600a. It should be understood that when the outer wall surface of the soaking plate body 600a is also attached with the passivation liquid, deionized water can also be used to clean the outer wall surface of the soaking plate body 600a to remove the passivation liquid remaining on the outer wall surface of the soaking plate body 600a.

[0179] (2) Perform a drying treatment on the soaking plate body to obtain a soaking plate body with a passivation film attached thereto.

[0180] After cleaning the soaking plate body 600a with deionized water, perform a drying treatment on the soaking plate body 600a to ensure the stability and reliability of the passivation film, so that the passivation film firmly adheres to the wall surface of the soaking plate body 600a, and obtain a soaking plate body 600a with a passivation film attached thereto that has good stability and high reliability.

[0181] When drying the heat pipe body 600a, it can be carried out in a vacuum environment. In this way, it can prevent the passivation film on the heat pipe body 600a that already has a passivation film from denaturing due to drying in an oxygen-containing atmosphere, so as to improve the stability and reliability of the passivation film and improve the drying efficiency.

[0182] In addition, when drying the heat pipe body 600a, the drying temperature can be 50°C - 90°C, and the drying time can be 1h - 24h. That is to say, the drying temperature of the heat pipe body 600a can be maintained between 50°C and 90°C, and the drying time of the heat pipe body 600a can be maintained between 1h and 24h. In this way, on the basis of being in a vacuum environment, the drying temperature is relatively high and the drying time is appropriate, which can improve the drying efficiency of the heat pipe body 600a, and when ensuring that the heat pipe body 600a is completely dried, improve the stability and reliability of the passivation film.

[0183] Exemplarily, the drying temperature of the heat pipe body 600a can be 60°C - 90°C to keep the drying temperature relatively high and accelerate the drying efficiency of the heat pipe body 600a. The drying time of the heat pipe body 600a can be 2h - 8h to reduce the drying time of the heat pipe body 600a on the premise of ensuring that the heat pipe 600 is completely dried. For example, the drying temperature of the heat pipe body 600a can be 65°C, 70°C, 75°C, 80°C, 85°C, etc. The drying time of the heat pipe body 600a can be 2.5h, 3.0h, 3.5h, 4.0h, 4.5h, 5.0h, 5.5h, 6.0h, 6.5h, 7.0h, 7.5h, etc.

[0184] After obtaining the heat pipe body 600a with a passivation film attached, the following steps can also be included:

[0185] (1) Inject liquid into the cavity of the heat pipe body and evacuate the air.

[0186] After obtaining the heat pipe body 600a with a passivation film attached, next, inject liquid into the cavity of the heat pipe body 600a. In other words, inject a coolant into the cavity of the heat pipe body 600a. For example, the coolant can be injected into the cavity of the heat pipe body 600a through a liquid injection port reserved on the wall surface of the heat pipe body 600a.

[0187] During or after the liquid injection process, evacuate the cavity of the heat pipe body 600a to discharge the air in the cavity of the heat pipe body 600a. Reserve enough space for the steam formed after the coolant evaporates to avoid air hindering the flow of the steam and ensure that the steam can flow smoothly along the steam channel 6101 to the condensation end of the heat pipe 600. Furthermore, ensure the stability and reliability of the operation of the heat pipe 600 and extend the service life of the heat pipe 600.

[0188] (2) Seal and shape the heat pipe body to obtain the heat pipe.

[0189] After injecting liquid into the cavity of the heat pipe body 600a and evacuating it, seal the heat pipe body 600a, that is, seal the liquid injection port on the heat pipe body 600a, so that the heat pipe body 600a forms a sealed cavity, ensuring that the heat pipe body 600a can work normally. After that, shape the heat pipe body 600a to ensure that the outer shape of the heat pipe body 600a is regular and simple, and obtain a heat pipe 600 with good appearance effect. It can also improve the appearance refinement of the heat pipe 600, ensure stable and reliable assembly of the heat pipe 600 with the heat source 700. Furthermore, ensure the reliability of the heat pipe 600 during operation and extend the service life of the heat pipe 600.

[0190] In this embodiment, the heat pipe body 600a is treated with a passivation solution containing a strong oxidant, and then the heat pipe body 600a is placed in a pressure-bearing furnace for passivation treatment. In this way, a uniform, dense and complete passivation film can be formed on the wall surface of the heat pipe body 600a. The passivation film has strong adhesion and high reliability, which can improve the corrosion resistance of the heat pipe body 600a. Furthermore, it can improve the stability of the working performance of the heat pipe 600, extend the service life of the heat pipe 600, and is beneficial to improving the heat dissipation performance of the electronic device 10.

[0191] Among them, for the heat pipe 600 obtained by using this manufacturing method, through material surface composition analysis, the results are as follows: when the metal materials of the upper cover plate 610 and the lower cover plate 620 of the heat pipe body 600a are titanium alloy and titanium metal composite plates, the main corrosion-resistant component on the wall surface of the heat pipe body 600a is TiO2; when the metal materials of the upper cover plate 610 and the lower cover plate 620 of the heat pipe body 600a are stainless steel, the main corrosion-resistant component on the wall surface of the heat pipe body 600a is Cr2O3. And, the thickness of the passivation film formed on the inner wall surface of the heat pipe body 600a is in the range of 10nm - 150nm.

[0192] It can be seen that a uniform, dense and complete passivation film is formed on the wall surface of the heat pipe body 600a. The passivation film has a certain thickness, strong adhesion and high reliability, and can effectively play the role of anti-corrosion. Among them, according to different factors such as the materials of the upper cover plate 610 and the lower cover plate 620 of the heat pipe body 600a, the size of the heat pipe body 600a, the type of strong oxidant in the passivation solution, and the parameters of the passivation treatment in the pressure-bearing furnace, the thickness of the passivation film formed on the inner wall surface of the heat pipe body 600a is also different.

[0193] Through the manufacturing method provided in this embodiment, the vapor chamber 600 used in the aforementioned small, light and thin electronic device 10 can be manufactured, for example, the vapor chamber 600 used in electronic devices 10 such as mobile phones, wearable devices, netbooks, and laptop computers can be manufactured. Since the volume of the vapor chamber 600 used in these electronic devices 10 is relatively small, the vapor chamber 600 manufactured by the manufacturing method of this embodiment is highly efficient and effective, and the wall surface of the vapor chamber body 600a can be fully oxidized, and a uniform, dense, and complete passivation film can be formed on the wall surface of the vapor chamber body 600a.

[0194] In addition, for the heat spreader made of titanium alloy, stainless steel and titanium metal composite plate, the surface of the conventional heat spreader is silvery white. In this embodiment, after the heat spreader body 600a is passivated, a dense passivation film is formed on the wall surface of the heat spreader body 600a, and the surface of the heat spreader body 600a will appear golden yellow, cyan blue and purple red, which also shows that the passivation effect of the heat spreader 600 is obvious.

[0195] For example, the surfaces of different vapor chamber bodies 600a may present different colors depending on the materials of the upper cover plate 610 and the lower cover plate 620 of the vapor chamber body 600a, the size of the vapor chamber body 600a, the type of strong oxidant in the passivation solution, the parameters of the passivation treatment in the pressure furnace, etc. For example, different vapor chamber bodies 600a present golden yellow, cyan blue, purple red, etc.

[0196] Alternatively, due to the different degrees of oxidation of different regions of the wall surface of the vapor chamber body 600a by the passivation liquid, different regions of a single vapor chamber body 600a may also present different colors. In other words, a single vapor chamber body 600a has multiple colors. For example, the wall surface of a single vapor chamber body 600a has at least two colors, for example, the wall surface of a single vapor chamber body 600a has golden yellow and cyan blue, or golden yellow and purple red, or purple blue and purple red, or golden yellow, cyan blue and purple red at the same time.

[0197] Several different examples are listed below, and data obtained by performing aging tests on the heat spreader 600 obtained through the manufacturing method of this embodiment after passivation treatment is compared with data obtained by performing aging tests on a conventional heat spreader that has not undergone the passivation treatment of this embodiment.

[0198] Among them, 18 samples (heat-vaporizing plates) of the conventional heat-vaporizing plates and the heat-vaporizing plates 600 (Examples 1 to 4 of the present application) after passivation treatment by the manufacturing method of the embodiment of the present application were taken, and placed at a temperature of 90° C. for 560 hours for aging test. The data obtained are as follows:

[0199] Table 1 (Conventional vapor chamber)

[0200] Serial number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 Temperature difference before aging (°C) 2.9 2.2 1.9 2.4 1.8 3.1 3.4 2.0 1.8 2.0 1.9 2.4 2.4 1.8 2.0 1.7 1.7 1.6 Temperature difference after aging (°C) 5.0 5.4 5.3 5.8 5.2 5.6 5.6 5.5 6.2 5.6 4.9 5.5 5.8 5.3 5.7 4.7 5.3 4.9

[0201] Example 1 of the present application:

[0202] First, inject a passivation solution containing a strong oxidant into the cavity of the welded vapor chamber body 600a. The strong oxidant is sodium hypochlorite, and its concentration in the passivation solution is 0.5 wt%. Place the above vapor chamber body 600a in a pressure-bearing furnace filled with air. Under this gas environment, perform passivation treatment on the vapor chamber body 600a at a preset temperature of 380°C and a predetermined time of 12 h. After the passivation treatment is completed, take out the vapor chamber body 600a after cooling it to room temperature in the furnace, wash the cavity of the vapor chamber body 600a thoroughly with deionized water, and perform drying treatment on the vapor chamber body 600a in a vacuum environment at a drying temperature of 60°C and a drying time of 6 h to obtain the vapor chamber body 600a with a passivation film attached thereto.

[0203] Table 2 (Example 1 of the present application)

[0204] Serial number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 Temperature difference before aging (°C) 3.6 2.5 2.7 2.4 1.9 2.3 3.7 2.1 3.3 3.5 2.0 2.8 2.6 2.9 3.6 2.9 3.2 2.8 Temperature difference after aging (°C) 3.7 3.0 3.1 2.6 2.4 2.1 4.2 2.5 2.7 3.6 1.8 2.8 2.4 2.7 3.4 2.5 4.0 3.0

[0205] Example 2 of the present application:

[0206] First, inject a passivation solution containing a strong oxidant into the cavity of the welded vapor chamber body 600a. The strong oxidant is peracetic acid, and its concentration in the passivation solution is 4.5 wt%. Place the above vapor chamber body 600a in a pressure-bearing furnace filled with oxygen. Under this gas environment, perform passivation treatment on the vapor chamber body 600a at a preset temperature of 300°C and a predetermined time of 72 h. After the passivation treatment is completed, take out the vapor chamber body 600a after cooling it to room temperature in the furnace, wash the cavity of the vapor chamber body 600a thoroughly with deionized water, and perform drying treatment on the vapor chamber body 600a in a vacuum environment at a drying temperature of 80°C and a drying time of 2 h to obtain the vapor chamber body 600a with a passivation film attached thereto.

[0207] Table 3 (Example 2 of the present application)

[0208] Serial number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 Temperature difference before aging (°C) 3.5 3.4 3.3 3.4 3.8 3.7 3.8 3.4 3.0 3.0 3.1 3.3 3.3 3.2 3.4 3.9 3.3 3.5 Temperature difference after aging (°C) 2.9 3.1 3.4 2.9 3.6 3.5 3.6 3.4 2.8 2.6 2.5 2.9 3.2 3.2 3.4 2.9 3.0 3.1

[0209] Example 3 of the present application:

[0210] First, inject a passivation solution containing a strong oxidant into the cavity of the heat pipe body 600a after welding. The strong oxidant is selected as potassium persulfate, and its concentration in the passivation solution is 1 wt%. Place the above heat pipe body 600a in a pressure-bearing furnace, and the gas filled in the pressure-bearing furnace is an oxygen-nitrogen mixture. Under this gas environment, perform a passivation treatment on the heat pipe body 600a at a preset temperature of 260 °C for a predetermined time of 96 h. After the passivation treatment is completed, take out the heat pipe body 600a after cooling it to room temperature in the furnace, select deionized water to fully clean the cavity of the heat pipe body 600a, and perform a drying treatment on the heat pipe body 600a at a drying temperature of 80 °C for a drying time of 3 h in a vacuum environment to obtain a heat pipe body 600a with a passivation film attached thereto.

[0211] Table 4 (Example 3 of the present application)

[0212] Serial number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 Temperature difference before aging (°C) 2.3 2.8 1.9 4.0 3.3 2.6 3.0 2.9 2.7 2.3 2.9 1.8 3.7 2.9 2.5 4.1 3.3 2.4 Temperature difference after aging (°C) 2.9 2.5 2.0 3.7 4.3 2.1 3.5 3.9 2.5 2.0 3.3 2.0 3.9 2.2 2.0 3.8 4.1 2.5

[0213] Example 4 of the present application:

[0214] First, inject a passivation solution containing a strong oxidant into the cavity of the heat pipe body 600a after welding. The strong oxidant is selected as potassium permanganate, and its concentration in the passivation solution is 2.5 wt%. Place the above heat pipe body 600a in a pressure-bearing furnace, and the gas filled in the pressure-bearing furnace is oxygen. Under this gas environment, perform a passivation treatment on the heat pipe body 600a at a preset temperature of 320 °C for a predetermined time of 60 h. After the passivation treatment is completed, take out the heat pipe body 600a after cooling it to room temperature in the furnace, select deionized water to fully clean the cavity of the heat pipe body 600a, and perform a drying treatment on the heat pipe body 600a at a drying temperature of 90 °C for a drying time of 2 h in a vacuum environment to obtain a heat pipe body 600a with a passivation film attached thereto.

[0215] Table 5 (Example 4 of the present application)

[0216] Serial number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 Temperature difference before aging (°C) 2.6 2.2 2.9 3.2 2.6 2.3 1.6 3.3 2.2 2.9 2.0 3.4 3.7 2.9 3.9 2.4 2.5 3.6 Temperature difference after aging (°C) 2.3 2.2 3.7 3.4 2.2 2.7 3.3 4.0 2.0 3.3 2.9 3.7 3.4 2.4 4.4 3.0 2.4 4.2

[0217] Among them, the temperature difference refers to the temperature difference between the evaporation end and the condensation end of the heat pipe. The temperature difference before aging refers to the temperature difference between the evaporation end and the condensation end of the heat pipe before the aging test. The temperature difference after aging refers to the temperature difference between the evaporation end and the condensation end of the heat pipe after the aging test.

[0218] In addition, it should be noted that taking the power of the heat pipe as 3.5W as an example, it can be considered that when the temperature difference of the heat pipe is greater than 5°C, it indicates that the heat pipe has a poor temperature equalization effect and low reliability. The heat pipe cannot dissipate heat for the heat source in a timely and effective manner, and the performance of the heat pipe is poor. On the contrary, when the temperature difference of the heat pipe ≤ 5°C, it can be considered that the heat pipe has a good temperature equalization effect and high reliability. The heat pipe can dissipate heat for the heat source in a timely and effective manner, and the performance of the heat pipe is better.

[0219] In this regard, according to the data of the aging test of the conventional heat pipe, it can be seen that after the conventional heat pipe undergoes the aging test, the temperature differences after aging of multiple samples among the 18 samples are unqualified (the bold data in the table). It is proved that the conventional heat pipe has a poor temperature equalization effect and low reliability, the performance of the heat pipe is poor, and the service life is short.

[0220] According to the aging test data of Examples 1 - 4 of the present application, it can be seen that for the heat pipe 600 manufactured by the manufacturing method of the embodiments of the present application, after the aging test, the temperature differences after aging of all 18 samples are qualified. It is proved that the heat pipe 600 manufactured by the manufacturing method of the embodiments of the present application has a good temperature equalization effect and high reliability, and the heat pipe 600 has good performance and a long service life.

[0221] In the description of the embodiments of the present application, it should be noted that unless otherwise clearly specified and limited, the terms "installed", "connected", and "coupled" should be understood in a broad sense. For example, it can be a fixed connection, or an indirect connection through an intermediate medium, and can be the communication inside two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to specific circumstances.

[0222] The terms "first", "second", "third", "fourth", etc. (if any) in the description and claims of the embodiments of the present application and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily need to be used to describe a specific order or sequence.

Claims

1. A method for manufacturing a heat pipe, characterized in that, Including: Obtaining a heat pipe body; Providing a passivation solution containing a strong oxidant, and injecting the passivation solution into at least the cavity of the heat pipe body; Placing the heat pipe body in a pressure-bearing furnace, and performing passivation treatment at a preset temperature and for a predetermined time; wherein, the pressure in the pressure-bearing furnace > 0.1 MPa; Taking out the heat pipe body, and performing post-treatment on the heat pipe body to obtain a heat pipe body with a passivation film attached thereto.

2. The method for manufacturing a heat pipe according to claim 1, characterized in that, The strong oxidant includes one of permanganate, persulfate, dichromate, peroxide, chlorate, and hypochlorite.

3. The method for manufacturing a heat pipe according to claim 1, characterized in that, The concentration of the strong oxidant in the passivation solution is 0.01 wt% - 15 wt%.

4. The method for manufacturing a heat pipe according to claim 3, characterized in that, The concentration of the strong oxidant in the passivation solution is 0.1 wt% - 5 wt%.

5. The method for manufacturing a heat pipe according to any one of claims 1-4, characterized in that, Injecting the passivation solution into at least the cavity of the heat pipe body includes: Immersing the heat pipe body in the passivation solution so that the passivation solution enters the cavity of the heat pipe body.

6. The method for manufacturing a heat pipe according to any one of claims 1-4, characterized in that, The pressure-bearing furnace has a sealed furnace cavity.

7. The method for manufacturing a heat pipe according to any one of claims 1-4, characterized in that, The gas filled in the pressure-bearing furnace includes one of air, oxygen, nitrogen, and oxygen-nitrogen mixture.

8. The method for manufacturing a heat pipe according to any one of claims 1-4, characterized in that, The preset temperature is 100°C - 600°C.

9. The method for manufacturing a heat pipe according to claim 8, characterized in that, The preset temperature is 250°C - 400°C.

10. The method for manufacturing a heat pipe according to any one of claims 1-4, characterized in that, The predetermined time is 10 h - 100 h.

11. The method for manufacturing a heat pipe according to claim 10, characterized in that, The predetermined time is 50 h - 100 h.

12. The method for manufacturing a heat pipe according to any one of claims 1-4, characterized in that, Performing post-treatment on the heat pipe body includes: Cleaning the cavity of the heat pipe body with deionized water; Performing drying treatment on the heat pipe body to obtain a heat pipe body with a passivation film attached thereto.

13. The method for manufacturing a heat pipe according to claim 12, characterized in that, Performing drying treatment on the heat pipe body includes: Performing drying treatment on the heat pipe in a vacuum environment.

14. The method for manufacturing a heat pipe according to claim 13, characterized in that, Performing drying treatment on the heat pipe body includes: When performing the drying treatment, the drying temperature is 50°C - 90°C, and the drying time is 1 h - 24 h.

15. The manufacturing method of the heat pipe according to claim 14, wherein, Performing drying treatment on the heat pipe body includes: When performing the drying treatment, the drying temperature is 60°C - 90°C, and the drying time is 2 h - 8 h.

16. The manufacturing method of the heat pipe according to any one of claims 1-4, wherein, Obtaining the heat pipe body includes: Processing and forming an upper cover plate and a lower cover plate with a metal material; Welding the upper cover plate and the lower cover plate to form the heat pipe body.

17. The manufacturing method of the heat pipe according to claim 16, wherein, The metal material for processing and forming the upper cover plate and the lower cover plate includes one of titanium alloy, stainless steel, and titanium metal composite plate.

18. The manufacturing method of the heat pipe according to any one of claims 1-4, wherein, After obtaining the heat pipe body with a passivation film attached thereto, it further includes: Injecting liquid and evacuating the cavity of the heat pipe body; Sealing and shaping the heat pipe body to obtain a heat pipe.

19. A heat pipe manufactured by using the manufacturing method according to any one of claims 1-18, wherein, The heat pipe includes a heat pipe body and a coolant, and the coolant is located in the cavity of the heat pipe body; Wherein, a passivation film is attached to the wall surface of the heat pipe body.

20. The heat pipe according to claim 19, wherein, The total thickness of the heat pipe ≤ 0.8 mm.

21. The heat pipe according to claim 19, wherein, The area of the heat pipe is ≤ 150 cm 2 .

22. The heat pipe according to any one of claims 19-21, wherein, The thickness of the passivation film attached to the inner wall surface of the heat pipe body is 10 nm - 150 nm.

23. An electronic device, wherein, Including a housing assembly and the heat pipe according to any one of claims 19 - 22, and the heat pipe is disposed in the housing assembly.

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