Novel capillary structure and vapor chamber using same
By employing a novel capillary structure and cover plate design, the problems of lightweighting and poor heat conduction and dissipation of the heat spreader are solved, achieving ultra-thinness and efficient heat conduction and dissipation, and enhancing structural stability and uniform heat distribution.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-13
- Publication Date
- 2026-03-24
AI Technical Summary
The thickness of the woven mesh capillary structure in existing heat spreaders is limited, making it difficult to achieve lightweight and thinner designs, while also resulting in poor heat conduction and dissipation.
A novel capillary structure is adopted, including through holes and annular protrusions on the foil, combined with grooves and support protrusions on the cover plate to form a water return path and a steam channel. Laser processing technology is used to achieve ultra-thinness and efficient heat conduction.
The heat spreader has been made lighter and thinner, while improving heat conduction and heat dissipation and structural strength, ensuring stable circulation of the cooling medium and uniform heat distribution, and improving heat conduction and heat dissipation efficiency.
Smart Images
Figure CN224037668U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to heat dissipation technical field, especially a novel capillary structure and the even temperature plate of application this novel capillary structure. BACKGROUND
[0002] With the development of electronic and electrical technology and the improvement of user demand, the function of various electronic products in daily life, scientific research and education is more and more, and the power is more and more big, and the heat of electronic product is more and more serious.
[0003] With the demand of portable electronic products, the lightness and thinness of the vapor chamber are put forward, and the capillary structure is the key component of the vapor chamber, which realizes the return of liquid by capillary action, thereby completing the heat transfer and heat dissipation.
[0004] In the prior art, the capillary structure in the vapor chamber usually adopts a woven wire mesh, and since the woven wire mesh is formed by crossing warp and weft, the thickness of the wire mesh is limited by the wire diameter and cannot be thin, and since the thinner wire diameter is easy to break, the processing difficulty is large, thereby leading to low yield.
[0005] The present application at least solves at least one of the above technical problems. SUMMARY
[0006] The utility model discloses a novel capillary structure and the even temperature plate of application this novel capillary structure, and the even temperature plate of application this novel capillary structure not only has good heat conduction and heat dissipation effect, but also has lightness and thinness and good structural strength.
[0007] The utility model discloses the following technical scheme is adopted to realize the purpose:
[0008] The utility model discloses a novel capillary structure, comprising:
[0009] The foil has a first face and a second face opposite along a thickness direction, and a plurality of through holes penetrating the foil along the thickness direction are arranged on the foil;
[0010] Each through hole is located at the edge of the second face of the foil, and a ring-shaped protrusion surrounding the edge is formed correspondingly,
[0011] Each of the annular protrusions corresponds to each of the through holes one by one.
[0012] In some possible implementation manners of the first aspect, the arrangement of the plurality of through holes is in a rectangular array, an annular array or an unequal-distance array.
[0013] In some possible implementation manners of the first aspect, the thickness of the foil is 0.005-0.015 mm, and / or the thickness of the novel capillary structure is 0.02-0.05 mm.
[0014] In some possible implementation manners of the first aspect, the aperture of the through hole is 0.02-0.15 mm; and
[0015] / Or the distance between the centers of two adjacent through holes is 0.04-0.3 mm.
[0016] In some possible implementation manners of the first aspect, compared with the prior art, the novel capillary structure has the following beneficial effects:
[0017] 1. The number, size, shape and arrangement of the through holes in the novel capillary structure can be designed and adjusted.
[0018] 2. The thickness of the novel capillary structure is 0.02-0.05 mm, realizing the application of an ultrathin vapor chamber.
[0019] 3. Compared with the traditional woven wire mesh, the novel capillary structure has a faster climbing speed in water absorption testing, a greater capillary force, a better capillary effect on water, and a better heat conduction and heat dissipation effect of the vapor chamber.
[0020] In the second aspect of the utility model, a vapor chamber is provided, the vapor chamber has a hot end in contact with a heat source and a cold end away from the heat source, a first direction from the hot end to the cold end and a second direction perpendicular to the first direction, the novel capillary structure obtained by the processing method or the novel capillary structure is applied, and the vapor chamber comprises:
[0021] A first cover plate has a first surface and a first back surface arranged oppositely along the thickness direction, the first cover plate is provided with a first groove, and the first groove is recessed from part of the first surface to the inside of the first cover plate;
[0022] A second cover plate has a second surface and a second back surface arranged oppositely along the thickness direction, the second cover plate is provided with a plurality of rows of support protrusions distributed at intervals along the second direction, a second groove is formed between two adjacent rows of support protrusions, and the support protrusions are recessed from part of the second surface to the inside of the second cover plate;
[0023] The new capillary structure is fitted in the first groove of the first cover plate, wherein the annular protrusions are located on the groove bottom wall of the first groove, and a backwater passage is formed between the adjacent two annular protrusions and the groove bottom wall of the first groove;
[0024] The first surface of the first cover plate and the second back surface of the second cover plate are covered, and the first cover plate and the second cover plate are fixedly connected, so that a closed inner cavity is formed between the first cover plate and the second cover plate, and the closed inner cavity is used for accommodating the new capillary structure and the cooling medium of the vapor chamber.
[0025] The support protrusion abuts against the new capillary structure, wherein the support protrusion abuts against the first surface of the foil.
[0026] The application improves the heat conduction and heat dissipation effect and structural strength of the vapor chamber, and realizes the lightness and thinness of the vapor chamber while having good heat conductivity and structural stability.
[0027] I. The capillary action of the new capillary structure can make the cooling medium in the vapor chamber quickly return to the heat source after being heated and evaporated, improve the heat conduction efficiency, and thus maintain continuous heat conduction circulation, thereby further improving the heat conduction and heat dissipation effect of the vapor chamber.
[0028] II. The support protrusion abuts against the new capillary structure, so that the support protrusion can play a good fixing role on the new capillary structure, and ensure that the new capillary structure is tightly fixed between the first cover plate and the second cover plate, thereby improving the stability of the new capillary structure in the vapor chamber.
[0029] III. The first groove and the second groove can form a large enough steam passage, so that the steam can be more fully diffused, the efficient transmission of heat in the vapor chamber is ensured, the heat is more evenly distributed on the entire vapor chamber, and the heat conduction and heat dissipation effect of the vapor chamber is enhanced. Avoiding that the heat cannot be efficiently and uniformly distributed on the entire vapor chamber due to the small steam passage, thereby affecting the evaporation effect.
[0030] IV. Compared with the traditional woven wire mesh, the new capillary structure has greater capillary force and better capillary effect, thereby improving the heat conduction and heat dissipation effect of the vapor chamber.
[0031] In some possible implementation manners of the second aspect, when the first cover plate and the second cover plate are made of stainless steel or titanium, the new capillary structure is made of stainless steel; or
[0032] When the first cover plate and the second cover plate are made of copper or copper-aluminum composite or copper-steel composite, the new capillary structure is made of copper; or
[0033] When the first cover plate and the second cover plate are made of titanium, the novel capillary structure is made of titanium.
[0034] In some possible implementation manners of the second aspect, the first cover plate comprises a first copper cover plate and a first aluminum cover plate arranged in layers; and the second cover plate comprises a second aluminum cover plate and a second copper cover plate arranged in layers.
[0035] The first aluminum cover plate has a first aluminum surface and a first aluminum back surface arranged oppositely along the thickness direction, the first copper cover plate has a first copper surface and a first copper back surface arranged oppositely along the thickness direction, the first aluminum surface and the first copper back surface are attached, and part of the first copper surface is recessed inwardly of the first cover plate to form the first groove.
[0036] The second aluminum cover plate has a second aluminum surface and a second aluminum back surface arranged oppositely along the thickness direction, the second copper cover plate has a second copper surface and a second copper back surface arranged oppositely along the thickness direction, the second aluminum back surface and the second copper surface are attached, and part of the second aluminum surface is recessed inwardly of the second cover plate to form a plurality of rows of the support protrusions, and the second groove is formed between two adjacent rows of the support protrusions.
[0037] In some possible implementation manners of the second aspect, the support protrusions are not in contact with the inner wall of the first groove.
[0038] In some possible implementation manners of the second aspect, the depth of the second groove is smaller than the depth of the first groove.
[0039] In some possible implementation manners of the second aspect, the thickness of the novel capillary structure is smaller than the depth of the second groove.
[0040] In some possible implementation manners of the second aspect, the thickness of the novel capillary structure is 0.02-0.05 mm.
[0041] In some possible implementation manners of the second aspect, the thickness of the first copper cover plate is 0.005-0.1 mm, the thickness of the first aluminum cover plate is 0.01-0.1 mm, the thickness of the second copper cover plate is 0.005-0.1 mm, and the thickness of the second aluminum cover plate is 0.01-0.1 mm. BRIEF DESCRIPTION OF DRAWINGS
[0042] Figure 1 FIG. 1 is a schematic view of a forming structure of a novel capillary structure according to an embodiment of the present application;
[0043] Figure 2 FIG. 2 is a schematic view of a guide groove in the novel capillary structure according to the embodiment of the present application;
[0044] Figure 3The distribution diagram of the first area and the second area of the first surface of the steel foil in the embodiment of the utility model is shown in the figure.
[0045] Figure 4 The distribution structure of the guide groove, the first area and the second area in the novel capillary structure in the embodiment of the utility model is shown in the figure.
[0046] Figure 5 The structure diagram of the uniform temperature plate in the embodiment of the utility model is shown in the figure.
[0047] In the figure, 1, first cover plate; 2, second cover plate; 3, novel capillary structure; 13, first groove; 21, second aluminum cover plate; 22, second copper cover plate; 23, supporting protrusion; 24, second groove; 31, foil; 32, through hole; 33, annular protrusion; 34, guide groove. DETAILED DESCRIPTION
[0048] Example implementations will now be described more fully with reference to the accompanying drawings. Example implementations may, however, be implemented in many different forms and should not be construed as limited to the implementations set forth herein; rather, these implementations are provided so that this disclosure will be thorough and complete, and will fully convey the inventive concept to those skilled in the art. Like reference numerals refer to like elements throughout the figures, and descriptions of the same elements will not be repeated.
[0049] In a first aspect of the embodiment, a processing method of a novel capillary structure is provided, comprising steps S1-S3.
[0050] Step S1: a foil 31 with a certain thickness is provided, the foil 31 has a first surface and a second surface opposite in the thickness direction.
[0051] The material of the foil 31 is selected to be stainless steel, titanium or copper, the thickness T1 of the foil 31 is 0.005-0.015 mm, for example, it can be 0.005 mm, 0.006 mm, 0.007 mm, 0.008 mm, 0.009 mm, 0.01 mm, 0.011 mm, 0.012 mm, 0.013 mm, 0.014 mm, 0.015 mm. In the embodiment, the material of the foil 31 is stainless steel, the thickness T1 of the foil 31 is 0.01 mm, the length is 150 mm, and the width is 50 mm.
[0052] Step S2: along the thickness direction of the foil 31, a laser beam is used to sequentially penetrate the first surface and the second surface of the foil 31, a plurality of interval distributed through holes 32 are formed on the foil 31, and each through hole 32 is located at the edge of the second surface of the foil 31, an annular protrusion 33 surrounding the edge is formed correspondingly, and a novel capillary structure 3 is obtained.
[0053] Referring to the drawings, Figure 1As shown, under the high-temperature heating effect of the laser beam, a local area on the surface of the foil 31 will be fused, thereby forming a through hole 32, and the metal material originally corresponding to the through hole 32 will be expanded outside on the second surface of the foil 31, thereby forming a ring-shaped protrusion 33 (metal burr) around the edge of the through hole 32.
[0054] It should be noted that each ring-shaped protrusion 33 corresponds to each through hole 32 one by one.
[0055] In some specific embodiments, the shape of the through hole 32 can be one or more of a polygon, a circle, an ellipse, or a water drop shape. It should be noted that the above-mentioned shapes are not a limitation on the shape of the through hole 32 in the present application. The shape of the through hole 32 can be regular or irregular, and the shapes of the plurality of through holes can be the same or different. In the present embodiment, the through hole 32 can be circular.
[0056] In some specific embodiments of the first aspect, the arrangement of the plurality of through holes 32 is in a rectangular array, a circular array, or an unequal distance array. In the present embodiment, the arrangement of the plurality of through holes 32 can be in a rectangular array.
[0057] In some specific embodiments of the first aspect, the aperture D of the through hole 32 is 0.02-0.15 mm. The apertures of the plurality of through holes 32 can be equal or unequal, for example, 0.02 mm, 0.03 mm, 0.04 mm, 0.05 mm, 0.06 mm, 0.07 mm, 0.08 mm, 0.09 mm, 0.1 mm, 0.011 mm, 0.012 mm, 0.013 mm, 0.014 mm, 0.015 mm. In the present embodiment, the aperture D of the through hole can be 0.06 mm.
[0058] Further, the distance H between the centers of two adjacent through holes 32 is 0.04-0.3 mm; preferably, H=2D. In the present embodiment, the distance H between the centers of two adjacent through holes 32 is 0.12 mm.
[0059] In some specific embodiments of the first aspect, the thickness T of the new capillary structure is 0.02-0.05 mm, and the thickness of the ring-shaped protrusion 33 is T2. It can be understood that T=T1+T2. In the present embodiment, the thickness T of the new capillary structure is 0.035 mm, and the thickness T2 of the ring-shaped protrusion 33 is 0.025 mm.
[0060] The number, size, shape, and arrangement of the through holes in the new capillary structure 3 in the present application can be designed and adjusted as needed. The thickness of the new capillary structure 3 is 0.02-0.05 mm, achieving the application of an ultra-thin uniform temperature plate.
[0061] The application can use low-power MOPA for laser beam processing, and only nanoseconds are needed to realize the integrated molding of the multiple through holes 32 and the annular protrusions 33 of the new capillary structure 3, which is simple and efficient; the laser processing can make the aperture D of the through hole reach a precision of 0.02 mm, and the spacing H between the centers of two adjacent through holes 32 can reach a precision of 0.04 mm, which cannot be achieved by traditional stamping processes (stamping is limited by mold processing, and the current research on through holes requires a minimum aperture of 0.1 mm and a minimum spacing H of 0.15 mm). Compared with traditional woven wire meshes, the new capillary structure 3 has a faster climbing speed and a larger capillary force in water absorption tests, and its capillary effect on water is better, which can improve the heat conduction and heat dissipation effect of the vapor chamber.
[0062] The second aspect of the embodiment also provides a new capillary structure, which is obtained by the above processing method, and is combined with the drawings. Figure 1 As shown in the drawings, the new capillary structure 3 includes a foil sheet 31.
[0063] The foil sheet 31 has a first face and a second face opposite in the thickness direction; and a plurality of through holes 32 penetrating the foil sheet in the thickness direction are arranged on the foil sheet 31.
[0064] Each through hole 32 is located at the edge of the second face of the foil sheet 31, and an annular protrusion 33 surrounding the edge is formed correspondingly.
[0065] Each annular protrusion 33 corresponds to each through hole 32.
[0066] Combined with the drawings, Figures 2-5 In some specific embodiments of the second aspect, at least one guide groove 34 penetrating the foil sheet 31 in the thickness direction is further arranged on the foil sheet 31.
[0067] In some specific embodiments of the second aspect, the first face of the foil sheet 31 includes a first region and a second region.
[0068] The density of the through holes 32 in the first region is greater than the density of the through holes 32 in the second region. The aperture of the through holes 32 in the first region is smaller than the aperture of the through holes 32 in the second region.
[0069] Combined with the drawings, Figure 5 The third aspect of the embodiment provides a vapor chamber processing method, which applies the above new capillary structure 3. The vapor chamber has a hot end in contact with a heat source and a cold end away from the heat source, and a direction from the hot end to the cold end is a first direction, and a direction perpendicular to the first direction is a second direction. The vapor chamber processing method includes the following steps S10-S12.
[0070] Step S10: providing a first cover plate 1 and a second cover plate 2, the first cover plate 1 is provided with a first groove 13, and the second cover plate 2 is provided with a plurality of rows of support protrusions 23 distributed at intervals along the second direction, and a second groove 24 is formed between two adjacent rows of support protrusions 23.
[0071] The cross-sectional shape of the first groove 13 and the second groove 24 can be rectangular, isosceles trapezoidal, etc., and the embodiment is preferably isosceles trapezoidal. The first groove 13 and the second groove 24 form a large enough steam passage, so that the steam can be more fully diffused, ensuring efficient heat transfer in the vapor chamber, and making the heat more evenly distributed on the entire vapor chamber, to enhance the heat dissipation effect of the vapor chamber.
[0072] When the first cover plate 1 and the second cover plate 2 are made of stainless steel or titanium, the new capillary structure 3 is made of stainless steel. When the first cover plate 1 and the second cover plate 2 are made of copper or copper-aluminum composite or copper-steel composite, the new capillary structure 3 is made of copper; when the first cover plate 1 and the second cover plate 2 are made of titanium, the new capillary structure 3 is made of titanium.
[0073] In one embodiment of the present embodiment, when the first cover plate 1 and the second cover plate 2 are made of stainless steel, the new capillary structure 3 is also made of stainless steel. In the present embodiment, the thickness of the first cover plate 1 is preferably 0.05mm; the thickness of the second cover plate 2 is preferably 0.05mm.
[0074] In another embodiment of the present embodiment, the first cover plate 1 and the second cover plate 2 can be made of copper-aluminum composite, and the new capillary structure 3 is made of copper.
[0075] Now the first cover plate 1 and the second cover plate 2 of the composite material will be specifically described. The first cover plate 1 includes a first copper cover plate and a first aluminum cover plate stacked, the first aluminum cover plate has a first aluminum surface and a first aluminum back surface oppositely arranged along the thickness direction, the first copper cover plate has a first copper surface and a first copper back surface oppositely arranged along the thickness direction, the first aluminum surface and the first copper back surface are attached, and part of the first copper surface is recessed inwardly of the first cover plate 1 to form the first groove 13. Preferably, the first cover plate 1 is symmetrical relative to the center line of the first groove 13.
[0076] The second cover plate 2 includes a second aluminum cover plate and a second copper cover plate stacked, the second aluminum cover plate has a second aluminum surface and a second aluminum back surface oppositely arranged along the thickness direction, the second copper cover plate has a second copper surface and a second copper back surface oppositely arranged along the thickness direction, the second aluminum back surface and the second copper surface are attached, and part of the second aluminum surface is recessed inwardly of the first cover plate 2 to form a plurality of rows of support protrusions 23, and a second groove 24 is formed between two adjacent rows of support protrusions 23.
[0077] The material of the first cover plate 1 includes copper having excellent thermal conductivity and ductility and aluminum having excellent thermal conductivity, light weight, ductility and corrosion resistance, so that the heat source conducts heat to the whole vapor chamber through the first cover plate 1.
[0078] The second cover plate 2 is far away from the heat source, and the material of the second cover plate 2 also includes copper having excellent thermal conductivity and ductility and aluminum having excellent thermal conductivity, light weight, ductility and corrosion resistance, and the second cover plate 2 sufficiently dissipates the heat conducted into the vapor chamber by the heat source.
[0079] It should be further explained that the thickness of the first copper cover plate is 0.005-0.1 mm, the thickness of the first aluminum cover plate is 0.01-0.1 mm, the thickness of the second copper cover plate is 0.005-0.1 mm, and the thickness of the second aluminum cover plate is 0.01-0.1 mm. The above thickness specifications can improve the heat dissipation effect of the vapor chamber while achieving ultra-thin. In the embodiment, the thickness of the first copper cover plate is preferably 0.01 mm, the thickness of the first aluminum cover plate is preferably 0.04 mm, the thickness of the second copper cover plate is preferably 0.01 mm, and the thickness of the second aluminum cover plate is preferably 0.04 mm.
[0080] In some embodiments, when the support protrusions 23 are double, the second cover plate 2 is symmetrical to the center line of the most central second groove 24 among all the second grooves 24; when the support protrusions 23 are single, the second cover plate 2 is symmetrical to the center line of the most central support protrusion 23 among all the support protrusions 23.
[0081] In some embodiments, before the steps of providing the first cover plate 1 and the second cover plate 2, there are steps S100-S300.
[0082] Step S100: providing a first substrate and a second substrate. The first substrate includes a first copper substrate and a first aluminum substrate which are sequentially stacked, and the second substrate includes a second aluminum substrate and a second copper substrate which are sequentially stacked.
[0083] Step S200: stamping the first substrate to form first grooves 13 on the first substrate, and the first substrate is stamped to form the first cover plate 1.
[0084] The first copper substrate and the first aluminum substrate are rolled into a first substrate, and then the first substrate is stamped to form the first grooves 13, thereby obtaining the first cover plate 1 provided with the first grooves 13.
[0085] Step S300: stamping the second substrate to form protrusions 23 on the second substrate, and the second substrate is stamped to form the second cover plate 2.
[0086] The second copper substrate and the second aluminum substrate are rolled into a second substrate, and then the second substrate is punched to form a plurality of columns of support protrusions 23 spaced apart along a second direction, and a second groove 24 is formed between two adjacent columns of support protrusions 23, thereby obtaining a second cover plate 2 provided with the support protrusions 23 and the second groove 24.
[0087] Because the copper cover plate and the aluminum cover plate in the first cover plate 1 and the second cover plate 2 will form an electrolyte when contacting impurities such as air, moisture and carbon dioxide, causing aluminum to become a negative electrode and copper to become a positive electrode, electrochemical corrosion occurs. The corrosion products (such as Al(OH)3 and AlO(OH)) produced by electrochemical corrosion will affect the heat conduction efficiency of the surface of the copper-aluminum composite plate. The contact resistance between copper and aluminum increases due to corrosion, affecting heat transfer and reducing the heat conduction performance of the heat spreader. Long-term corrosion may damage the structure of the first cover plate 1 and the second cover plate 2, affecting the overall structural strength of the heat spreader.
[0088] Therefore, in some preferred embodiments, the copper plate and the aluminum plate in the first cover plate 1 and the second cover plate 2 are tightly bonded and connected into one by cold rolling or explosive rolling, forming a solder-free structure, which effectively prevents the negative effects of electrochemical corrosion on the heat dissipation effect and structural strength of the heat spreader.
[0089] Step S11: providing a new type of capillary structure 3, and bonding the new type of capillary structure 3 in the first groove 13 of the first cover plate 1.
[0090] Further, the annular protrusions 33 of the new type of capillary structure 3 are bonded and fixed to the groove bottom wall of the first groove 13, and a backwater passage is formed between the adjacent two annular protrusions 33 and the groove bottom wall of the first groove 13.
[0091] Further, the annular protrusions 33 of the new type of capillary structure 3 can be bonded and fixed to the groove bottom wall of the first groove 13 of the first cover plate 1 by diffusion welding; or the new type of capillary structure 3 can be fixed to the groove bottom wall of the first groove 13 of the first cover plate 1 by resistance welding or laser welding.
[0092] In order to ensure that the new type of capillary structure 3 has good bonding strength with the first cover plate 1, in this embodiment, part of the annular protrusions 33 are first fixed in the first groove 13 of the first cover plate 1 by resistance welding or laser welding for positioning, and then the new type of capillary structure 3 is tightly bonded to the groove bottom wall of the first groove 13 of the first cover plate 1 by diffusion welding. The process conditions of diffusion welding include: the welding gas is a mixture of nitrogen and hydrogen gas (nitrogen accounts for 5-10%), the gas flow rate is 100-200 L / min, the welding temperature is 250-500℃, and the welding pressure is 10000-20000PSL.
[0093] The capillary action of the annular protrusion 33 of the new capillary structure 3 makes the cooling medium in the vapor chamber quickly return to the heat source after being heated and evaporated, reduces the resistance of the cooling medium during the return process, and further reduces the overall thermal resistance of the vapor chamber, improves the heat dissipation efficiency, and maintains the continuous heat conduction cycle. On the other hand, the annular protrusion 33 is attached to the bottom wall of the first groove 13 and does not extend to the side wall of the first groove 13, which increases the contact area between the side wall of the first groove 13 and the cooling medium, meaning that the cooling medium is more fully in contact with the inner wall of the first cover plate 1, which increases the path and efficiency of heat transfer, allowing more heat to be evenly distributed throughout the vapor chamber, allowing more heat to be directly transferred from the first cover plate 1 to the cooling medium, reducing the resistance of heat transfer, and thus improving the heat dissipation efficiency.
[0094] It should be further noted that the thickness of the new capillary structure 3 is less than the depth (D1) of the first groove 13. The thickness of the new capillary structure 3 + the depth (D2) of the second groove 24 = the depth of the first groove 13. In a preferred embodiment, the depth of the second groove 24 is greater than the thickness of the new capillary structure 3, the thickness of the new capillary structure 3 is 0.035mm, the depth of the first groove 13 is 0.15mm, and the depth of the second groove 24 is 0.115mm. The vapor chamber with this specification has good heat dissipation effect.
[0095] Because the depth of the second groove 24 is greater than the thickness of the new capillary structure 3, the contact area between the side wall of the second groove 24 and the cooling medium in the vapor chamber is increased, meaning that the cooling medium is more fully in contact with the inner wall of the second cover plate 2, which increases the path and efficiency of heat transfer, allowing more heat to be evenly distributed throughout the vapor chamber, allowing more heat to be directly transferred from the second cover plate 2 to the cooling medium, reducing the resistance of heat transfer, and thus further improving the heat dissipation efficiency.
[0096] Further, the inner wall of the first groove 13 does not contact the support protrusion 23. This is to prevent the first cover plate 1 from being covered by the second cover plate 2, as the support protrusion 23 and the inner wall of the first groove 13 interfere with each other, preventing the new capillary structure 3 from fully abutting the support protrusion 23, affecting the reliability of the vapor chamber, and thus negatively affecting the heat dissipation effect and service life of the vapor chamber.
[0097] Further, the depth of the first groove 13 is greater than the depth of the second groove 24, and the depth of the first groove 13 is 0.15mm and the depth of the second groove 24 is 0.115mm. On the one hand, it is to ensure that the thickness of the vapor chamber is ultra-thin, and on the other hand, it is to ensure that the first groove 13 can accommodate the new capillary structure 3, so that the new capillary structure 3 can abut the support protrusion 23.
[0098] Step S12: The first cover plate 1 is overlapped with the second cover plate 2 so that the supporting protrusion 23 is in abutment with the new type of capillary structure 3, and the first cover plate 1 and the second cover plate 2 are fixedly connected to form a closed inner cavity between the first cover plate 1 and the second cover plate 2, which is used to accommodate the new type of capillary structure 3 and the cooling working medium of the vapor chamber.
[0099] The abutment of the supporting protrusion 23 and the new type of capillary structure 3 can enable the supporting protrusion 23 to play a good fixing role on the new type of capillary structure 3, ensuring that the new type of capillary structure 3 can be fixed tightly between the first cover plate 1 and the second cover plate 2, and improving the stability of the new type of capillary structure 3 inside the vapor chamber.
[0100] The stable structure of the new type of capillary structure 3 can ensure that the cooling working medium (usually water or other cooling liquid) inside the vapor chamber can circulate smoothly during the evaporation and condensation process. When one end of the vapor chamber is heated, the working medium will evaporate into steam, which will diffuse inside the vapor chamber and carry heat. Subsequently, the steam condenses into liquid at the cooler end, releasing heat. During this process, the stability of the new type of capillary structure 3 ensures that the working medium can flow smoothly from one area to another, thereby achieving efficient heat transfer. In addition, the stability of the new type of capillary structure 3 also enhances the overall structural strength of the vapor chamber. The vapor chamber may be subjected to various external pressures and impacts during operation, and the stable structure of the new type of capillary structure 3 can effectively resist these external forces, maintaining the integrity of the vapor chamber. This not only prolongs the service life of the vapor chamber, but also ensures its stability and reliability in various application scenarios. Finally, the stability of the new type of capillary structure 3 also helps to improve the heat conduction efficiency of the vapor chamber. When heat is transferred through the vapor chamber, the new type of capillary structure 3 can quickly conduct heat from the heat source to the entire vapor chamber, achieving uniform heat distribution. This uniform heating effect is crucial for improving the heat dissipation performance of electronic equipment, as it can effectively reduce the risk of local overheating, thereby protecting electronic components from damage.
[0101] It should be noted that the cooling working medium is a liquid phase change material, such as liquid water, ethanol, and acetone, etc. Through the transformation process of the cooling working medium from liquid to gas and then to liquid, heat is quickly dissipated, thereby achieving the heat conduction and dissipation effect of the vapor chamber. To ensure that the transformation process of the cooling working medium from liquid to gas and then to liquid is not affected by impurities, the closed inner cavity is generally in a vacuum state, thereby improving the heat conduction and dissipation effect of the vapor chamber. In this embodiment, the cooling working medium is water.
[0102] In a specific implementation of the third aspect, the step of overlapping the first cover plate 1 with the second cover plate 2 includes steps S120a-S122a.
[0103] Step S120a: Covering the side of the second cover plate 2 forming the support protrusion 23 to the side of the first cover plate 1 forming the first groove 13, so that the support protrusion 23 abuts against the new type of capillary structure 3.
[0104] Step S121a: The first part of the side of the first cover plate 1 forming the first groove 13 except the first groove 13 corresponds to the second part of the side of the second cover plate 2 forming the support protrusion 23 except the support protrusion 23.
[0105] Step S122a: The first part and the second part are sealed along the preset molecular diffusion area by diffusion welding.
[0106] In this embodiment, a low-temperature diffusion furnace is used, and the process conditions of diffusion welding include: the welding gas is a nitrogen-hydrogen mixed gas (nitrogen accounts for 5-10%), the gas flow rate is 100-200 L / min, the welding temperature is 250-500°C, and the welding pressure is 10000-20000 PSL.
[0107] Because the melting point of aluminum is low, the first cover plate 1 and the second cover plate 2 can be tightly combined together by low-temperature and low-pressure diffusion welding process. Because the gas during welding is a nitrogen-hydrogen mixed gas for protection during work, there is no need to perform reduction treatment, and the back-end process can be directly performed.
[0108] In another embodiment, the difference from the foregoing embodiment is that the method of covering the first cover plate 1 and the second cover plate 2 is different, and the method of covering the first cover plate 1 and the second cover plate 2 in this embodiment includes steps S120b-S122b.
[0109] Covering the side of the second cover plate 2 forming the support protrusion 23 to the side of the first cover plate 1 forming the first groove 13, so that the support protrusion 23 abuts against the new type of capillary structure 3.
[0110] The first part of the side of the first cover plate 1 forming the first groove 13 except the first groove 13 corresponds to the second part of the side of the second cover plate 2 forming the support protrusion 23 except the support protrusion 23.
[0111] The first part and the second part are sealed along the preset sealing line by laser welding. In this embodiment, a laser welding machine is used for laser welding.
[0112] Further, after the first cover plate 1 and the second cover plate 2 are covered by laser welding, the covered first cover plate 1 and the second cover plate 2 are subjected to low-temperature reduction treatment, and the conditions of low-temperature reduction are: the reduction gas is a nitrogen-hydrogen mixed gas (nitrogen accounts for 5-10%), the gas flow rate is 100-200 L / min, and the reduction temperature is 250-500°C.
[0113] The sealing efficiency of laser welding is high, and it can be completed in about 1-5s. However, there is no protective gas during laser welding, so the copper layer will be oxidized. Therefore, a low-temperature reduction treatment is performed to eliminate the residual stress and deformation of the welding part, so as to ensure the mechanical properties of the uniform temperature plate.
[0114] In combination with the accompanying Figure 5 The fourth aspect of the embodiment also provides a uniform temperature plate processed by the above method. The uniform temperature plate has a hot end in contact with a heat source, a cold end away from the heat source, a first direction from the hot end to the cold end, and a second direction perpendicular to the first direction. The uniform temperature plate comprises a first cover plate 1, a second cover plate 2, and a new type of capillary structure 3.
[0115] The first cover plate 1 has a first surface and a first back surface arranged oppositely along the thickness direction. The first cover plate 1 is provided with a first groove 13 formed by recessing part of the first surface towards the inside of the first cover plate 1.
[0116] The second cover plate 2 has a second surface and a second back surface arranged oppositely along the thickness direction. The second cover plate 2 is provided with a plurality of rows of support protrusions 23 distributed along the second direction. A second groove 24 is formed between two adjacent rows of support protrusions 23. The support protrusions 23 are formed by recessing part of the second surface towards the inside of the second cover plate 2. The inner wall of the first groove 13 does not contact the support protrusions 23. The depth of the second groove 24 is less than the depth of the first groove 13. The first cover plate 1 and the second cover plate 2 are made of the same material, which is stainless steel.
[0117] The new type of capillary structure 3 is attached to the first groove 13 of the first cover plate 1. The thickness of the new type of capillary structure 3 is less than the depth of the second groove 24. It should be noted that the annular protrusion 33 of the new type of capillary structure 3 is located on the groove bottom wall of the first groove 13, and a backwater passage is formed between the adjacent two annular protrusions 33 and the groove bottom wall of the first groove 13.
[0118] The first surface of the first cover plate 1 and the second back surface of the second cover plate 2 are overlapped, and the first cover plate 1 and the second cover plate 2 are fixedly connected, so that a closed inner cavity is formed between the first cover plate 1 and the second cover plate 2. The closed inner cavity is used to accommodate the new type of capillary structure 3 and the cooling working medium of the uniform temperature plate.
[0119] The support protrusions 23 abut against the new type of capillary structure 3. It should be noted that the support protrusions 33 abut against the first face of the foil 31 of the new type of capillary structure 3.
[0120] It should be noted that, due to the existence of the included angle between the annular protrusion 33 and the groove bottom wall of the first groove 13, a capillary force is generated around the contact edge of the annular protrusion 33 and the groove bottom wall, and the capillary force can absorb more water than other areas under the capillary action, thereby forming a water storage area; when the heat source heats the cooling working medium of the hot end, the cooling working medium will vaporize to form water vapor, and a pressure difference will be formed in the closed inner cavity. Under the action of the pressure difference, the water vapor diffuses through the through hole 32 to the cold end to condense into water, and is fully collected in the water storage area. Since the adjacent two annular protrusions 33 and the groove bottom wall of the first groove 13 form a water return passage, under the pressure difference formed by the condensation of water vapor into water and the capillary action at the edge of the annular protrusion 33, the water in the water storage area will quickly return to the hot end through the water return passage, thereby accelerating the heat conduction cycle and enabling the heat source to more quickly conduct heat and dissipate heat, thereby improving the heat conduction and dissipation effect of the entire vapor chamber.
[0121] In combination with the accompanying drawings, Figures 1-4 In some specific embodiments, the hole diameter D of the through hole 32 is 0.02-0.15 mm, and the distance H between the centers of the adjacent two through holes 32 is 0.04-0.3 mm.
[0122] The larger the hole diameter, the smaller the resistance of the water vapor passing through the foil, and the higher the transmittance. However, when the hole diameter increases, the distance between the centers of the adjacent two through holes also increases, and a larger capillary force is required to pull the cooling working medium from the cold end back to the hot end, which increases the resistance of water return between the adjacent two water storage areas in the direction from the cold end to the hot end. The smaller the hole diameter, the greater the resistance of the water vapor passing through the foil 31, and the smaller the transmittance. When the hole diameter decreases, the distance between the centers of the adjacent two through holes also decreases, and a smaller capillary force is required to pull the water from the cold end back to the hot end, which reduces the resistance of water return between the adjacent two water storage areas in the direction from the cold end to the hot end. Therefore, the through hole 32 under this specification can not only have a high transmittance of water vapor but also have a small enough resistance of water return, and the water vapor has a good transmittance and water return effect, thereby accelerating the heat conduction cycle of the heat source and improving the heat conduction and dissipation effect of the vapor chamber.
[0123] In some specific embodiments, the foil 31 is further provided with at least one guide groove 34 penetrating the foil 31 in the thickness direction.
[0124] It should be noted that the guide groove 34 is away from the hot end of the vapor chamber and close to the cold end of the vapor chamber. Since the size of the guide groove 34 is much larger than that of the through hole 32, the resistance of the water vapor passing through the guide groove 34 is small, and the transmittance is high. Under the action of the pressure difference, the water vapor can be quickly pushed to the cold end for condensation, thereby further accelerating the heat conduction cycle of the condensed water and returning to the hot end, improving the heat conduction and dissipation effect of the vapor chamber, and accelerating the heat dissipation of the heat source.
[0125] In some specific embodiments of the second aspect, the first surface of the foil 31 comprises a first region and a second region, the density of the through holes 32 in the first region is greater than the density of the through holes 32 in the second region, and it is noted that the first region is close to the hot end.
[0126] This makes the aperture of the through holes 32 in the first region smaller than the aperture of the through holes 32 in the second region, and more water can be stored in the water storage region under the action of capillary force to conduct heat away from the heat source.
[0127] In some embodiments, the first cover plate 1 comprises a first copper cover plate and a first aluminum cover plate which are stacked; and the second cover plate 2 comprises a second aluminum cover plate and a second copper cover plate which are stacked.
[0128] The first aluminum cover plate has a first aluminum surface and a first aluminum back surface which are oppositely arranged along the thickness direction, the first copper cover plate has a first copper surface and a first copper back surface which are oppositely arranged along the thickness direction, the first aluminum surface and the first copper back surface are attached, and part of the first copper surface is recessed inwardly of the first cover plate 1 to form a first recess 13.
[0129] The second aluminum cover plate has a second aluminum surface and a second aluminum back surface which are oppositely arranged along the thickness direction, the second copper cover plate has a second copper surface and a second copper back surface which are oppositely arranged along the thickness direction, the second aluminum back surface and the second copper surface are attached, and part of the second aluminum surface is recessed inwardly of the second cover plate 2 to form a plurality of rows of protrusions 23, and a second recess 24 is formed between two adjacent rows of protrusions.
[0130] Embodiments of the application will be described in detail below with reference to examples, but those skilled in the art will understand that the following examples are only for illustration of the application and should not be regarded as limiting the scope of the application.
[0131] The new type of capillary structure and the traditional woven wire mesh were subjected to water absorption tests, and the climbing speed was tested, and the test method was as follows: the new type of capillary structure and the woven wire mesh were respectively welded by resistance welding on the same specified area (in the specified area, the new type of capillary structure and the woven wire mesh were one-to-one corresponding to the steel sheet in the length direction and the width direction) of a steel sheet with a length of 180 mm, a width of 70 mm and a thickness of 10 mm, to obtain a test product.
[0132] The test product was hung by one end along the length direction of the steel sheet as the top, and the other end as the bottom (at this time, the top and bottom of the new type of capillary structure and the traditional woven wire mesh along the length direction of the steel sheet were at the same height), and the test product was sent into the water along the length direction of the steel sheet by a lifting device, and the time was started to be counted after the bottom of the test product contacted the water, and the time for the water to climb from the bottom of the test product to the top (i.e. the length direction of the steel sheet) of the test product was counted, so as to represent the climbing speed of the new type of capillary structure and the woven wire mesh.
[0133] The above test products were subjected to 6 water absorption tests, and their average climbing speeds were calculated. Example 1
[0134] The size parameters of the novel capillary structure are as follows:
[0135] The foil 31 is made of stainless steel, with a thickness T1 of 0.01 mm, a length of 150 mm, a width of 50 mm, and circular through holes. The through holes 32 are arranged in a rectangular array. The diameter D of the through holes is 0.06 mm. The distance H between the centers of two adjacent through holes 32 is 0.12 mm. The thickness T of the novel capillary structure is 0.035 mm, and the thickness T2 of the annular protrusion 33 is 0.025 mm.
[0136] It should be noted that the number of through holes 32 is set to the maximum along the length and width directions of the foil based on the diameter and distance of the through holes. Example 2
[0137] The size parameters of the novel capillary structure are as follows:
[0138] The foil 31 is made of stainless steel, with a thickness T1 of 0.01 mm, a length of 150 mm, a width of 50 mm, and circular through holes. The through holes 32 are arranged in a rectangular array. The diameter D of the through holes is 0.1 mm. The distance H between the centers of two adjacent through holes 32 is 0.25 mm. The thickness T of the novel capillary structure is 0.035 mm, and the thickness T2 of the annular protrusion 33 is 0.025 mm.
[0139] It should be noted that the number of through holes 32 is set to the maximum along the length and width directions of the foil based on the diameter and distance of the through holes.
[0140] Comparative Example 1
[0141] A stainless steel woven wire mesh with a length of 150 mm, a width of 50 mm, a thickness of 0.06 mm, and a mesh number of 250.
[0142] Comparative Example 2
[0143] A stainless steel woven wire mesh with a length of 150 mm, a width of 50 mm, a thickness of 0.065 mm, and a mesh number of 400.
[0144] The test data of Examples 1-2 and Comparative Examples 1-2 are shown in Table 1.
[0145]
[0146] It can be seen from the above examples and comparative examples that the climbing speed of the novel capillary structure is faster than that of the conventional woven wire mesh, which indicates that the capillary force is greater and the capillary effect is better, and when the novel capillary structure is applied to the vapor chamber, the vapor chamber can be thinned and the heat conduction and heat dissipation effect of the vapor chamber can be significantly improved.
[0147] Although the embodiments of the present application have been shown and described above, it should be understood that the above examples are exemplary and should not be construed as limiting the present application, and those skilled in the art can make changes, modifications, replacements and variations to the above examples without departing from the principles and purposes of the present application within the scope of the present application, and all these changes should belong to the protection scope of the claims of the present application.
Claims
1. A novel capillary structure characterized in that, The application relates to a novel capillary structure, comprising: a foil having a first surface and a second surface opposite along a thickness direction; a plurality of through holes penetrating through the foil along the thickness direction are arranged on the foil; each through hole is located at an edge of the second surface of the foil, and a ring-shaped protrusion is formed around the edge, each ring-shaped protrusion corresponds to each through hole.
2. The novel capillary structure according to claim 1, characterized in that, The arrangement of the plurality of through holes is in a rectangular array, a ring-shaped array or an unequal-distance array.
3. The novel capillary structure according to claim 1, wherein The thickness of the foil is 0.005-0.015 mm; and / or The thickness of the novel capillary structure is 0.02-0.05 mm.
4. The novel capillary structure according to claim 1, wherein The aperture of the through hole is 0.02-0.15 mm; and / or the distance between the centers of two adjacent through holes is 0.04-0.3 mm.
5. The novel capillary structure according to claim 1, wherein At least one guide groove penetrating through the foil along the thickness direction is further arranged on the foil.
6. The novel capillary structure according to claim 1, wherein The first surface of the foil comprises a first region and a second region; the density of the through holes in the first region is greater than that in the second region; and / or the aperture of the through holes in the first region is smaller than that in the second region.
7. The novel capillary structure according to claim 1, wherein The shape of the through hole comprises one or more of a polygon, a circle, an ellipse and a water-drop shape.
8. A vapor chamber having a hot side in contact with a heat source and a cold side away from the heat source and a first direction from the hot side to the cold side and a second direction perpendicular to the first direction, characterized by, The novel capillary structure is applied to the uniform temperature plate, and the uniform temperature plate comprises: a first cover plate having a first surface and a first back surface opposite along a thickness direction, the first cover plate being provided with a first groove formed by recessing part of the first surface to the inside of the first cover plate; a second cover plate having a second surface and a second back surface opposite along a thickness direction, the second cover plate being provided with a plurality of columns of support protrusions distributed at intervals along the second direction, a second groove being formed between two adjacent columns of support protrusions, the support protrusions being formed by recessing part of the second surface to the inside of the second cover plate; a novel capillary structure fitted into the first groove of the first cover plate, wherein the ring-shaped protrusions are located on the groove bottom wall of the first groove, and a backwater passage is formed between two adjacent ring-shaped protrusions and the groove bottom wall of the first groove; the first surface of the first cover plate and the second back surface of the second cover plate are overlapped, and the first cover plate and the second cover plate are fixedly connected to form a closed inner cavity between the first cover plate and the second cover plate, the closed inner cavity being used for accommodating the novel capillary structure and a cooling medium of the uniform temperature plate; the support protrusions abut against the novel capillary structure, wherein the support protrusions abut against the first surface of the foil.
9. The vapor chamber of claim 8, wherein, when the first cover plate and the second cover plate are made of stainless steel or titanium, the novel capillary structure is made of stainless steel; or when the first cover plate and the second cover plate are made of copper or copper-aluminum composite or copper-steel composite, the novel capillary structure is made of copper; or when the first cover plate and the second cover plate are made of titanium, the novel capillary structure is made of titanium.
10. The vapor chamber of claim 8, wherein, the first cover plate comprises a first copper cover plate and a first aluminum cover plate arranged in layers; and the second cover plate comprises a second aluminum cover plate and a second copper cover plate arranged in layers. The first aluminum cover plate has a first aluminum surface and a first aluminum back surface arranged oppositely along a thickness direction, the first copper cover plate has a first copper surface and a first copper back surface arranged oppositely along a thickness direction, the first aluminum surface and the first copper back surface are attached, and part of the first copper surface is recessed inwardly of the first cover plate to form the first recess. The second aluminum cover plate has a second aluminum surface and a second aluminum back surface arranged oppositely along a thickness direction, the second copper cover plate has a second copper surface and a second copper back surface arranged oppositely along a thickness direction, the second aluminum back surface and the second copper surface are attached, and part of the second aluminum surface is recessed inwardly of the second cover plate to form a plurality of rows of the support protrusions, and the second recess is formed between two adjacent rows of the support protrusions.
11. The vapor chamber of claim 8, wherein, The support protrusions are not in contact with inner walls of the first recess.
12. The vapor chamber of claim 8, wherein, The second recess has a depth smaller than that of the first recess.
13. The vapor chamber of claim 8, wherein, The novel capillary structure has a thickness smaller than that of the second recess.