CN203454875U - Vapor chamber - Google Patents

Abstract

The utility model discloses a soaking plate with simple structure, simple and convenient manufacture, lower cost and good heat conduction effect and a manufacturing method thereof. The soaking plate comprises a heated plate and a flat-plate-shaped heat dissipation plate, the inner face of the heated plate is provided with a groove, the flat-plate-shaped heat dissipation plate is welded with the heated plate, a vacuum inner cavity filled with working media is formed between the heat dissipation plate and the groove, and the heated plate in the vacuum inner cavity is partially provided with a capillary structure layer formed by sintering elemental metal powder. The utility model discloses simple manufacture makes the working medium on the evaporation condensation area can be adsorbed by the capillary structure layer fast moreover to reach the effect of the quick heat conduction of high-speed circulation. The supporting columns of the capillary structures are further arranged in the vacuum inner cavity, so that the backflow effect after steam condensation is more obvious, and the phenomenon of invagination or crack deformation caused by overhigh temperature or external pressure is avoided. The vapor chamber has the advantages of uniform heat dissipation, low thermal resistance, simple structure, low cost, few manufacturing processes, easy operation and suitability for automatic, intensive and large-scale production.

Description

Vapor

technical field

The utility model relates to a radiator for dissipating the working heat of electronic components and a manufacturing method thereof, in particular to a soaking plate for guiding away the working heat of an IC chip and a manufacturing method thereof.

Background technique

With the advancement of technology, today's electronic equipment is developing towards multi-function, high speed, and small size. The heat generated by IC chips per unit area has increased significantly. How to improve heat dissipation methods has always been a major challenge for the industry. Taking the CPU of a computer server as an example, its calorific value has exceeded 100W/cm ² . How to effectively dissipate the working heat generated by the small-area CPU to the environment, the cooling technology must be continuously improved to improve the heat dissipation efficiency.

In the prior art, the mainstream cooling methods are mainly fans, fins, and fins combined with heat pipes, such as aluminum extruded heat sinks, aluminum stamped heat sinks, aluminum or copper cutting heat sinks, and copper-aluminum and heat pipe embedded heat sinks, etc. . The most typical radiator and heat dissipation device is a finned heat pipe radiator with a fan, and the purpose of heat dissipation is achieved by contacting the radiator with the heat source 91 .

With the continuous improvement of chip integration, the heat of the heat source 91 of the electronic component 9 continues to increase, and the above-mentioned heat sink is far from meeting the heat dissipation requirements. Therefore, a vapor chamber 1 with good thermal conductivity must be installed between the heat source 91 of the electronic component 9 and the above-mentioned heat sink. Its function is to evenly distribute the heat generated by the heat source 91 of the electronic component 9 and quickly transfer it to the fins. Its working principle is shown in Figure 1. One side (referred to as heating plate 2) is in contact with the surface of heat source 91 of electronic component 9, and the other side (referred to as heat dissipation plate 3) is a transitional heat conducting member connected to the external fins. The heat receiving plate 2 on the soaking plate 1 absorbs The heat of the heat source 91 of the electronic component 9 makes the liquid working medium 7 in the evaporation area 21 in the vacuum cavity 11 vaporize and evaporate into steam 71, which is dissipated to the condensation area 31 on the cooling plate 3 and quickly transfers the heat energy to all The heat dissipation plate 3 where the fins are connected, through heat exchange, the heat energy is transferred to the fins and dissipated in the environment, and the steam 71 evaporated in the vacuum cavity 11 to the condensation area 31 of the heat dissipation plate 3 surrenders heat energy, condenses and then flows back to the The evaporation zone 21 at the heating plate 2 is circulated at such a high speed, so that the heat on the heat source 91 is quickly dissipated.

Vapor chamber 1 in the prior art is still immature in technical exploration. Although the theoretical principle is simple, the internal structure design methods are various and too complicated, especially in the manufacturing process, which is difficult and costly (see Figure 5). , vapor chambers 1 in the prior art can be roughly classified into the following two categories:

1) Etch several horizontal and vertical staggered fine grooves on the inner surface of the heating plate 2 and heat dissipation plate 3 of the vapor chamber 1, and place a grid and a flow guide bracket 8 in the vacuum cavity 11 to make the condensed working medium 7 Flow along the guide frame 8 to the evaporation area 21 at the heating plate 2 . The manufacturing process of this structure is complicated and the cost is extremely high, and its heat conduction effect will be greatly affected by the different positions of the vapor chamber 1 .

2) A capillary structure layer 22 is sintered in the evaporation area 21 on the heating plate 2 of the vapor chamber 1 and the condensation area 31 on the heat dissipation plate 3, and an independent structure guide is placed between the heating plate 2 and the heat dissipation plate 3 The bracket 8 is used to make the condensed working medium 7 flow from the guide bracket 8 to the evaporation area 21 at the heating plate 2 . This structure needs to sinter the capillary structure layer 22 on both sides of the heating plate 2 and the heat dissipation plate 3, which increases the production cost and wastes materials, because the capillary structure layer 22 in the condensation area 31 on the heat dissipation plate 3 will store a large amount of condensed work. If the medium 7 cannot be guided into the evaporation area 21 at the heating plate 2 in time, it will greatly affect the heat dissipation conduction efficiency of the vaporized working medium 7 on the heat dissipation plate 3 .

Both of the above two structures have disadvantages such as complex manufacture and high cost.

Utility model content

The technical problem to be solved by the utility model is to provide a vapor chamber with simple structure, easy manufacture, low cost and good heat conduction effect and its manufacturing method.

In order to solve the above technical problems, the technical solution adopted by the utility model is:

The soaking plate of the utility model includes heat absorbing and heat dissipating parts, the heat absorbing part is a heat receiving plate with a groove on the inner surface, and the heat dissipating part is a flat heat dissipating plate welded together with the inner surface of the heat receiving plate. A vacuum inner cavity filled with working medium is formed between the cooling plate and the groove, and a capillary structure layer sintered by simple metal powder is arranged on the heating plate part in the vacuum inner cavity.

At least two capillary structure support columns perpendicular to the groove bottom surface and integrated with the capillary structure layer are uniformly arranged on the bottom surface of the groove, and the support columns extend toward the heat dissipation plate and connect to each other.

The metal powder is copper powder with a mesh number of 50-150.

Both the heating plate and the heat dissipation plate are made of oxygen-free copper material.

The working medium is pure water, acetone or methanol, and the injection volume is 10%-40% of the volume of the inner cavity.

The degree of vacuum in the vacuum inner cavity is 10 ^-2 Pascal-10 ^-5 Pascal.

The thickness of the capillary structure layer is 0.3mm-0.8mm.

The method for manufacturing the vapor chamber of the present invention is to weld a heat receiving plate with a capillary structure layer and a heat dissipation plate made of a metal material with good thermal conductivity to form a vapor chamber with a vacuum cavity, and the steps are as follows:

1) Select two metal sheets with a thickness of 0.2mm-1.6mm, one of which is punched to form a heating plate with grooves on the inner surface and reserved for exhaust pipe positions, and the other is a flat heat dissipation plate;

2) Clean, decontaminate and dry the heating plate and cooling plate;

3) Put the pre-designed mold made of graphite material into the groove of the heating plate, and fill the elemental metal powder between the mold and the bottom surface and side wall of the groove; or put the pre-designed mold made of graphite material into In the groove of the heating plate, at least two hollow column tubes perpendicular to the bottom surface of the groove are arranged in the mold, and metal powder is filled between the mold and the bottom surface of the groove, the side wall and the column tube;

4) Vibrating the heated plate filled with metal powder in a vibrator, so that the filling density of the metal powder reaches 2-5 g/cm ³ ;

5) Put the heated plate into a furnace filled with protective gas and have heating, heat preservation and cooling sections suitable for the metal of the heated plate for sintering;

6) Take out the heating plate with the capillary structure layer sintered in the groove, or the heating plate with the capillary structure layer and the capillary structure support column sintered in the groove, and remove the mold;

7) Combine the cooling plate with the heating plate in a way of sealing the groove, and put it into a heat sink that is filled with protective gas and has heating, heat preservation and cooling sections that are suitable for welding the cooling plate and the heating plate. High temperature sealing in the furnace;

8) Take out the sealed cooling plate and heating plate, pump out the air in the inner cavity to a vacuum of 10 ^-2 Pascal - 10 ^-5 Pascal;

9) Inject the working medium and seal the exhaust pipe.

Both the heating plate and the heat dissipation plate are made of oxygen-free copper material.

During sintering, the speed of the heating section is 6°C/min to 900°C, the holding section is maintained at 900°C for 50 minutes, and the cooling section is at a rate of 2°C/min to room temperature.

Compared with the prior art, the vapor chamber of the utility model adopts the structure of capillary structure layer sintered by simple metal powder and a flat heat dissipation plate on the inner surface of the heating plate, which makes the utility model simple to manufacture and enables evaporation to heat dissipation. The steam of the working medium on the inner surface of the plate can be quickly absorbed by the capillary structure layer after condensation, so as to achieve the effect of high-speed circulation and rapid heat conduction. In the present utility model, when a support column with a capillary structure that is connected with the capillary structure layer and connected with the heat dissipation plate is provided in the vacuum inner cavity, the reflux effect of the steam after condensation is more significant, and, After the working medium stored in the capillary structure layer of the heating plate evaporates, the liquid working medium stored in the support column can be replenished in the capillary structure layer of the heating plate in time; The hot plate will not cause indentation or crack deformation due to its temperature or external pressure. Because the utility model only sets the capillary structure layer on the inner surface of the heating plate, it not only simplifies the manufacture of the soaking plate, but also reduces the manufacturing cost, and whether the soaking plate of the utility model is installed at an inclination, horizontally inverted, horizontally upright or The vertical arrangement has little effect on the return direction and speed of the working medium after condensation, thus effectively improving its working stability and reliability.

The manufacturing method of the vapor chamber of the utility model has the advantages of simple process, less process flow and easy operation, and is suitable for automatic, intensive and large-scale production.

Description of drawings

Below in conjunction with accompanying drawing and specific embodiment, the utility model is further described.

Figure 1 is a schematic diagram of the working principle of the vapor chamber.

Fig. 2 is a three-dimensional schematic view of the vapor chamber of the present invention.

Fig. 3 is a sectional view of A-A in Fig. 2 .

Fig. 4 is a schematic diagram of explosion of the vapor chamber structure of the present invention.

Fig. 5 is a temperature distribution diagram of a heat dissipation plate of a vapor chamber in the prior art.

Fig. 6 is a temperature distribution diagram of the heat dissipation plate of the vapor chamber of the present invention.

Fig. 7 is a graph showing changes in total thermal resistance when the vapor chambers of the present invention are arranged in different directions.

Fig. 8 is a curve diagram of pressure resistance and deformation of the vapor chamber of the present invention.

The reference signs are as follows:

Vapor chamber 1, vacuum chamber 11, heating plate 2, evaporation area 21, capillary structure layer 22, support column 23, heat dissipation plate 3, condensation area 31, groove 4, exhaust pipe 5, installation hole 6, working medium 7 , steam 71, liquid droplet 72, diversion bracket 8, electronic component 9, heat source 91.

Detailed ways

As shown in Figures 2, 3, and 4, the soaking plate 1 of the present invention is composed of a heat-absorbing heat-receiving plate 2 and a heat-dissipating plate 3 welded together with the heat-receiving plate 2 for heat dissipation. The outer surface of the heat-receiving plate 2 It is in contact with the heat source 91 of the electronic component 9 , the outer surface of the cooling plate 3 is in contact with the external fins, and there are installation holes 6 around the vapor chamber 1 . The heat receiving plate 2 and the heat dissipation plate 3 are made of metal materials with good thermal conductivity, such as copper or aluminum. The heat receiving plate 2 and the heat dissipation plate 3 can be made of the same metal, or can be used in combination of different metals. In the utility model, the thin plate made of oxygen-free copper is preferably used to make the heating plate 2 and the heat dissipation plate 3, and the thickness of the thin plate is in the range of 0.2mm-1.6mm, preferably 0.5mm, 0.8mm, 1.0mm or 1.2mm.

The inner surface of the heating plate 2 is provided with a groove 4, and the shape of the groove 4 depends on the shape of the heat source 91 of the electronic component 9, and can be circular, oval, triangular, quadrangular, pentagonal or hexagonal. In the shape of a polygon, a capillary structure layer 22 with a thickness of 0.3mm-0.8mm is provided on the bottom surface of the groove 4 (that is, the evaporation area 21) and the side surface, preferably 0.5mm in thickness. The capillary structure layer 22 is sintered by elemental metal powder , the mesh number of metal powder d ₅₀ is 50-150mesh, the utility model is preferably copper powder, the mesh number of its d ₅₀ is 80mesh.

As a further improvement of the utility model, several support columns 23 that are perpendicular to the bottom surface of the groove 4 and are integrated with the capillary structure layer 22 and have the same capillary structure can also be evenly arranged on the bottom surface of the groove 4. The shape of the support column 23 It is in the shape of a truncated cone, and its bottom end diameter is 2mm-8mm, preferably 5mm. The support column 23 extends toward the opening direction of the groove 4 .

The inner surface of the heat dissipation plate 3 (that is, the condensation area 31) is a smooth flat plate, and its inner surface is welded to the inner surface of the heat receiving plate 2, thereby forming an inner cavity between the heat dissipation plate 3 and the groove 4 , the inner cavity becomes a vacuum inner cavity 11 after being evacuated and sealed, and then injected into the vacuum inner cavity 11 is the working medium 7 that evaporates into steam 71 when heated, and condenses into liquid droplets 72 when cooled and dissipated to form a working medium 7. A complete vapor chamber 1 that conducts heat.

If when the inner cavity is provided with the support column 23, the top of the round table of the support column 23 is connected with the inner surface of the heat dissipation plate 3, and the support column 23 adopts a structure with a small top and a large bottom, which can not only quickly absorb the condensing area 31 after condensation working medium 7, but also can expand the area of the condensation zone 31 as much as possible, in addition, the top of the support column 23 is welded and fixedly connected with the inner surface of the heat dissipation plate 3, due to the pulling effect of the support column 23, it can also prevent the uniformity The hot plate 1 is cracked or deformed due to temperature change or external pressure.

The working medium 7 is pure water, acetone or methanol, and the injection amount is 10%-40% of the inner cavity volume. When the working medium 7 is pure water, the injection amount is preferably 15-40% of the inner cavity volume. 30%. The above preferred ratio can make the working medium 7 in the vacuum cavity 11 in the best evaporation-condensation-reflux working state, without low evaporation efficiency caused by too much liquid working medium 7 or interruption caused by lack of liquid working medium 7 The occurrence of heat absorption.

The vacuum degree in the vacuum inner cavity 11 is between ^10-2 Pascals and ^10-5 Pascals, preferably ^10-3 Pascals, so that the vacuum conditions required for the working medium 7 to be heated and evaporated can be satisfied, and the vacuum can be saved. The time, financial resources and power resources spent in pumping to a high vacuum state.

The beneficial effects produced by the vapor chamber 1 of the utility model adopting an integral internal capillary structure are as follows:

(1) Strengthen capillary force

As shown in Figure 6, the sintering of copper powder produces a capillary structure, which provides a circulation path for the working fluid and enhances the evaporation phenomenon on the surface. The capillary structure connects the entire steam 71 cavity from the evaporation area 21 on the heating plate 2 of the vapor chamber 1 to the condensation area 31 on the heat dissipation plate 3, and greatly enhances the working medium 7 in the condensation area 31 in the form of droplets 72. Backflow ability, timely and effectively replenish the working medium 7 to the evaporation area 21, shorten the cycle of evaporation, exchange and backflow, thereby improving the working efficiency and improving the uniformity of the temperature distribution of the cooling plate 3.

(2) Support function

As shown in Figure 8, the capillary structure support column 23 connected with the capillary structure layer 22 of the evaporation area 21 can make the vapor chamber 1 formed by the combination of the heating plate 2 and the heat dissipation plate 3 have strong support and compression resistance. ability, when the vacuum inner chamber 11 is in a low-pressure state, the support column 23 can fully play a supporting role, so that the heating plate 2 and the heat dissipation plate 3 will not be deformed due to external pressure, thereby ensuring that the heat receiving plate 2 and the heat dissipation plate 3 The flatness of the outer surface prevents the thermal resistance between the heating plate 2 and the electronic component 9, and between the cooling plate 3 and the external fins from increasing to reduce the effect of heat conduction and heat dissipation.

(3) Anti-thermal expansion function

When the heat source 91 or the ambient temperature exceeds the normal limit, due to the complete evaporation of the working medium 7, it may cause the air pressure in the vacuum cavity 11 to rise, because the top of the support column 23 is welded to the inner surface of the heat dissipation plate 3, by This also enables the heating plate 2 to be firmly combined with the heat dissipation plate 3 through the support column 23. This structure can effectively avoid the phenomenon of desoldering and cracking between the heating plate 2 and the heat dissipation plate 3 due to the rapid expansion of gas in the vacuum inner cavity 11. happened.

(4) Good directionality

As shown in Figure 7, in the actual application process of the product, the position and direction of the vapor chamber 1 should be adapted to the setting of the electronic component 9, that is, the vapor chamber 1 will be installed obliquely, inverted horizontally, upright horizontally or vertically Therefore, the heat conduction and heat dissipation efficiency of the vapor chamber 1 cannot be changed with the direction and position of the vapor chamber 1, that is, the difference in total thermal resistance cannot be too large. The soaking plate 1 of the present utility model, because the capillary structure layer 22 and the capillary structure connected with the capillary structure layer 22 in the evaporation region 21 are only set on the evaporation region 21 of the heating plate 2 and the side wall of the groove 4 The support column 23, so that the working medium 7 in the form of liquid droplets 72 evaporated to the condensation zone 31 and condensed will overcome the gravity and be quickly absorbed by the capillary structure layer 22 and the support column 23 of the capillary structure, without the occurrence of the The droplet 72-shaped working medium 7 stays in a certain non-evaporation area 21 due to the inclined setting, horizontal inversion or vertical setting of the vapor chamber 1 . Therefore, no matter how the vapor chamber 1 of the present invention is set, the working medium 7 in the shape of droplets 72 condensed in the condensation zone 31 can flow back to the evaporation zone 21 in time, that is, the working medium 7 in the shape of droplets 72 Medium 7 reflow has good directionality.

The manufacturing method of the utility model soaking plate 1 is as follows:

1) Select two thin plates of oxygen-free copper (C1020) with a thickness of 0.5mm, 0.8mm, 1.0mm or 1.2mm. Mounting holes 6 for assembling the vapor chamber 1 on the electronic component 9 are provided at the four corners of the heat dissipation plate 3 .

The outer dimension of the heating plate 2 is 90mm×90mm, and a groove 4 is arranged on its inner surface. The groove 4 is made by punching. Regular quadrilateral (the specific shape, area and depth of the groove 4 shall be determined according to the shape and area of the surface of the heat source 91 of the electronic component 9 used in conjunction with the vapor chamber 1 and the size of its installation space inside the electronic device) 1. At the corner of the heating plate 2 (on any corner or on any side), punch a concave position communicating with the groove 4 to embed the copper air extraction pipe 5.

The shape and size of the heat sink 3 and the heating plate 2 are the same, and it is formed into a flat plate by stamping and blanking, and its inner surface is a smooth surface (in the case of disregarding the manufacturing process and cost, several strips can also be etched on the inner surface. horizontal and vertical staggered fine diversion grooves).

2) Clean, decontaminate and dry the heating plate 2 and the cooling plate 3 .

3) Place the heating plate 2 on the workbench with the opening of the groove 4 upward, and then put the pre-designed mold made of graphite material into the groove 4 of the heating plate 2.

Described mold has two kinds, and a kind of is the die identical with described groove 4 shape, when putting in groove 4, there is certain gap between this mold and the bottom surface of described groove 4, sidewall. gap; the other is to set several hollow columns perpendicular to the bottom surface of the die on the basis of the previous mold (the cross-sectional shape of the column can be circular, triangular or oval, It can be a straight cylinder with the same area up and down, or a cylindrical cylinder with a large bottom and a small top). Except for a certain gap, the hollow cylinder communicates with the bottom surface of the groove 4 .

When using the first type of mold, fill the elemental copper powder between the mold and the bottom surface of the groove 4 and the side wall; Filled with elemental copper powder.

4) The heating plate 2 filled with copper powder is placed in a vibrator to vibrate, so that the filling density of the metal powder reaches the set 2-5 g/cm ³ .

5) Put the heating plate 2 into a protective gas (the protective gas is a nitrogen-hydrogen mixture with a mixing ratio of 95:5, or other gases commonly used in the prior art) and has a metal compatible with the heating plate 2 Sintering is carried out in a hot furnace in the heating, holding and cooling sections.

The preferred sintering temperature of the utility model is that the speed of the heating section is 6° C./min to 900° C., the holding section is maintained at 900° C. for 50 minutes, and the cooling section drops to room temperature at a rate of 2° C./min.

6) Take out the heating plate 2 with the capillary structure layer 22 sintered in the groove 4, or the heating plate 2 with the capillary structure layer 22 and the capillary structure support column 23 sintered in the groove 4, and remove the mold.

7) Combine the cooling plate 3 with the heating plate 2 in a way of sealing the groove 4, put it into the heating plate 2 filled with protective gas and have a heating and heat preservation mechanism suitable for welding the cooling plate 3 and the heating plate 2 High-temperature sealing is carried out in the hot furnace in the cooling section.

Use welding technology to weld the airtight vapor chamber 1 at one time, and then use high-frequency welding to put the copper exhaust pipe 5 for injecting the working medium 7 and air extraction into the concave position and weld it with the vapor chamber 1 as a whole.

8) Take out the sealed cooling plate 3 and heating plate 2, and pump out the air in the inner cavity to a vacuum degree of 10 ^-2 Pascals - 10 ^-5 Pascals, preferably 10 ^-3 Pascals.

When vacuumizing and degassing vapor chamber 1, when the vacuum degree drops to 10 ^-1 Pascal, the vacuum degree can reach 10 ^-2 Pascal to 10 ^-3 Pascal after 10 minutes of degassing time.

9) After the degassing is completed, an appropriate amount of working medium 7 can be injected into the vacuum inner cavity 11, and the exhaust pipe 5 can be sealed and welded.

The vapor chamber 1 in the prior art has defects such as complicated structural design, difficult control of the production process, and high production cost. These defects have always restricted the development of this industry. With the goal of saving energy, a vapor chamber 1 using a single substance, formed at one time, an integral functional structure, and capable of performing multiple functions has been produced. The structure is practical, the production is simplified, and energy is saved. Its various performances are very good, and its comprehensive effect is excellent. It is a new design and production standard for the popularization and use of vapor chamber 1 in the future. Simply put, the utility model is "feasible, usable, and earnable".

The above content is a further detailed description of the utility model in conjunction with specific preferred embodiments, and it cannot be assumed that the specific implementation of the utility model is only limited to these descriptions. On the premise of not departing from the concept of the utility model, some simple deduction or replacement can also be made, which should be regarded as belonging to the patent protection scope of the utility model determined by the submitted claims.

Claims (7)

1. A vapor chamber, including heat-absorbing and heat-dissipating parts, characterized in that: the heat-absorbing part is a heating plate (2) with a groove (4) on the inner surface, and the heat-dissipating part is connected to the heating plate (2) A flat heat dissipation plate (3) welded together on the inner surface, and a vacuum cavity (11) filled with a working medium (7) is formed between the heat dissipation plate (3) and the groove (4). The heating plate (2) part in the vacuum inner cavity (11) is provided with a capillary structure layer (22) formed by sintering elemental metal powder. 2. The vapor chamber according to claim 1, characterized in that: on the bottom surface of the groove (4), there are at least two layers perpendicular to the bottom surface of the groove (4) and connected to the capillary structure layer (22). A support column (23) of a capillary structure connected in one piece, the support column (23) extends to and connects to the heat dissipation plate (3). 3. The vapor chamber according to claim 2, wherein the metal powder is copper powder with a mesh number of 50-150. 4. The vapor chamber according to claim 2, characterized in that: the heating plate (2) and the heat dissipation plate (3) are both made of oxygen-free copper material. 5. The vapor chamber according to claim 2, characterized in that: the working medium (7) is pure water, acetone or methanol, and the injection volume is 10%-40% of the volume of the inner cavity. 6. The vapor chamber according to claim 2, characterized in that: the degree of vacuum in the vacuum inner chamber (11) is in the range of 10 ⁻² Pascals to 10 ⁻⁵ Pascals. 7. The vapor chamber according to any one of claims 1-6, characterized in that: the capillary structure layer (22) has a thickness of 0.3mm-0.8mm.

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