A laser cooling heat sink having a microchannel structure

Abstract

The application discloses a laser cooling heat sink with a micro-channel structure, which comprises a micro-channel heat sink working end, a heat-conducting metal filling layer, a micro-channel heat dissipation reinforcing end and a heat sink base, the micro-channel heat sink working end and the micro-channel heat dissipation reinforcing end are sequentially arranged in the heat sink base, the working surface of the micro-channel heat sink working end is attached to the cooling surface of a laser crystal, the heat dissipation surface of the micro-channel heat sink working end is provided with a micro-channel structure, the micro-channel structure is connected with the micro-channel heat dissipation reinforcing end which is also provided with a micro-channel structure through the heat-conducting metal filling layer, the micro-channel structure is formed by pressing the heat dissipation ribs which are arranged in a staggered mode, liquid inlet holes and liquid outlet holes which are communicated with the micro-channel structure are formed in the heat sink base, the micro-channel structure is formed by pressing the heat dissipation ribs which are arranged in a staggered mode, the controllability of machining is higher, the machining difficulty is greatly reduced, the precision requirement of the machining equipment is greatly reduced, and the production cost is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of laser, in particular to a laser cooling heat sink with micro-channel structure. BACKGROUND

[0002] As the core device of laser industry, the service life and long time safe and stable operation of laser are necessary conditions for realizing the application of laser technology. Since laser is an active optical device that converts electrical energy into required optical energy, a large part of energy is converted into heat during operation, and a high-efficiency heat management scheme is needed to reasonably dissipate heat from the laser gain medium, so as to ensure long service life and high-performance laser output of laser.

[0003] Generally, liquid or solid cooling heat sink is needed to contact the heat dissipation surface of the laser gain medium for heat dissipation. The cooling heat sink structure with micro-channel structure can greatly improve the heat dissipation area of the heat sink by processing regular distributed heat dissipation grooves and heat dissipation ribs on the heat dissipation surface, thereby significantly improving the heat dissipation capacity of the cooling heat sink, and thus becoming a reasonable heat management scheme for laser, especially high-power laser.

[0004] In order to realize higher heat dissipation capacity, it is usually necessary to process as many heat dissipation grooves and heat dissipation ribs as possible on the unit area of the cooling heat sink heat dissipation surface to increase the heat dissipation area, which greatly increases the machining difficulty and cost. SUMMARY

[0005] Technical purpose: in view of the defects of large machining difficulty and high cost of the micro-channel of the existing laser cooling heat sink, the present application discloses a laser cooling heat sink with micro-channel structure formed by assembling heat dissipation ribs and heat dissipation grooves, which can reduce the machining difficulty and cost.

[0006] Technical scheme: in order to realize the above technical purpose, the present application adopts the following technical scheme:

[0007] A laser cooling heat sink with micro-channel structure, comprising a micro-channel heat sink working end, a micro-channel heat dissipation strengthening end and a heat sink base, the micro-channel heat sink working end and the micro-channel heat dissipation strengthening end are sequentially arranged in the heat sink base, the working surface of the micro-channel heat sink working end is attached to the cooling surface of the laser crystal, the cooperation surface between the micro-channel heat sink working end and the micro-channel heat dissipation strengthening end is pressed together to form the micro-channel structure through the staggered heat dissipation ribs, and the heat sink base is provided with liquid inlet hole and liquid outlet hole communicated with the micro-channel structure.

[0008] Preferably, the micro-channel structure of the present application comprises first heat dissipation ribs arranged on the heat dissipation surface of the working end of the micro-channel heat sink and second heat dissipation ribs arranged on the heat dissipation reinforcing end of the micro-channel heat sink, first heat dissipation grooves with the same height as the first heat dissipation ribs are formed between adjacent first heat dissipation ribs, second heat dissipation grooves with the same height as the second heat dissipation ribs are formed between adjacent second heat dissipation ribs, the width of the first heat dissipation grooves is greater than the width of the second heat dissipation ribs, the width of the second heat dissipation grooves is greater than the width of the first heat dissipation ribs, the first heat dissipation ribs and the second heat dissipation ribs are arranged alternately, the first heat dissipation ribs are inserted into the second heat dissipation grooves, and the second heat dissipation ribs are inserted into the first heat dissipation grooves, and micro-channels for the flow of cooling liquid are formed between the first heat dissipation ribs and the second heat dissipation grooves and between the second heat dissipation ribs and the first heat dissipation grooves.

[0009] Preferably, the width of the first heat dissipation ribs is half the width of the first heat dissipation grooves, the width of the second heat dissipation ribs is half the width of the second heat dissipation grooves, and the width of the first heat dissipation ribs is equal to the width of the second heat dissipation ribs.

[0010] Preferably, the height of the second heat dissipation ribs is greater than the height of the first heat dissipation ribs, the end of the second heat dissipation ribs and the groove bottom of the first heat dissipation grooves are in abutment through a heat-conductive metal filling layer, the difference between the height of the second heat dissipation ribs and the height of the first heat dissipation ribs is 0.3 mm, and the heat-conductive metal filling layer adopts a 10 mu m gold plating layer or a 10 mu m indium foil layer.

[0011] Preferably, the working end of the micro-channel heat sink of the present application adopts a high-thermal-conductivity metal material with a thermal expansion coefficient close to that of the laser gain medium, and the material of the heat dissipation reinforcing end of the micro-channel heat sink is the same as that of the working end of the micro-channel heat sink.

[0012] Beneficial effects: The laser cooling heat sink with a micro-channel structure provided by the present application has the following beneficial effects:

[0013] 1. The micro-channel structure of the laser cooling heat sink of the present application forms a micro-channel structure by pressing the heat dissipation ribs arranged alternately, the number and gap of the micro-channel structure depend on the thickness difference between the heat dissipation ribs and the heat dissipation grooves, and micro-channels can be formed between the two sides of each heat dissipation rib and the heat dissipation grooves. For the same number of micro-channels, the processing width of the present application is only twice that of the existing processing method, and since the micro-channels are formed by matching gaps, the processing precision is more controllable and is more conducive to processing, and the demand for equipment is reduced.

[0014] 2. The height of the second heat dissipation ribs is greater than the height of the first heat dissipation ribs, the end of the second heat dissipation ribs and the groove bottom of the first heat dissipation grooves are in abutment through a heat-conductive metal filling layer, heat can be directly transmitted to the second heat dissipation ribs, contact heat exchange is achieved, and the heat dissipation efficiency is improved.

[0015] 3、the difference between the height of the second heat dissipation rib and the first heat dissipation rib is half of the difference between the width of the first heat dissipation groove and the second heat dissipation rib, so that the width of the microchannel formed is the same, and the uniformity of heat dissipation is improved. BRIEF DESCRIPTION OF DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced below.

[0017] Figure 1 is a schematic structural view of the cooling heat sink of the present application;

[0018] Figure 2 is a sectional view of the cooling heat sink of the present application;

[0019] Figure 3 is a partial enlarged view of the A area in the present application; Figure 2

[0020] wherein, 1-microchannel heat sink working end, 2-microchannel heat dissipation reinforcing end, 3-heat sink base, 4-thermally conductive metal filling layer, 5-first heat dissipation rib, 6-second heat dissipation rib, 7-first heat dissipation groove, 8-second heat dissipation groove, 9-microchannel. DETAILED DESCRIPTION

[0021] The present application will be more clearly and completely described below by means of a preferred embodiment and in conjunction with the drawings, but the present application is not limited in the scope of the described embodiments.

[0022] As Figures 1-3 shown is a laser cooling heat sink with a microchannel structure disclosed by the present application, a microchannel heat sink working end 1, a microchannel heat dissipation reinforcing end 2 and a heat sink base 3, the microchannel heat sink working end 1 and the microchannel heat dissipation reinforcing end 2 are sequentially arranged in the heat sink base 3, the working surface of the microchannel heat sink working end 1 is attached to the cooling surface of the laser crystal, the cooperation surface between the microchannel heat sink working end 1 and the microchannel heat dissipation reinforcing end 2 is pressed to form the microchannel structure through the staggered heat dissipation ribs, and the heat sink base 3 is provided with liquid inlet holes and liquid outlet holes which are communicated with the microchannel structure.

[0023] ​Specifically, the micro-channel structure comprises first heat dissipation ribs 5 arranged on the heat dissipation surface of the micro-channel heat sink working end 1 and second heat dissipation ribs 6 arranged on the micro-channel heat dissipation reinforcing end 2, first heat dissipation grooves 7 with the same height as the first heat dissipation ribs 5 are formed between adjacent first heat dissipation ribs 5, second heat dissipation grooves 8 with the same height as the second heat dissipation ribs 6 are formed between adjacent second heat dissipation ribs 6, the width of the first heat dissipation grooves 7 is greater than the width of the second heat dissipation grooves 8, the width of the second heat dissipation grooves 8 is greater than the width of the first heat dissipation ribs 5, the first heat dissipation ribs 5 and the second heat dissipation ribs 6 are arranged alternately, the first heat dissipation ribs 5 are inserted into the second heat dissipation grooves 8, the second heat dissipation ribs 6 are inserted into the first heat dissipation grooves 7, and micro-channels 9 for cooling liquid flow are formed between the first heat dissipation ribs 5 and the second heat dissipation grooves 8 and between the second heat dissipation ribs 6 and the first heat dissipation grooves 7, preferably, the width of the first heat dissipation ribs 5 is half the width of the first heat dissipation grooves 7, the width of the second heat dissipation ribs 6 is half the width of the second heat dissipation grooves 8, and the width of the first heat dissipation ribs 5 is equal to the width of the second heat dissipation ribs 6.

[0024] The micro-channels are formed through the matching gaps between the first heat dissipation ribs 5 and the second heat dissipation grooves 8 and between the second heat dissipation ribs 6 and the first heat dissipation grooves 7, as long as the width of the heat dissipation ribs and the heat dissipation grooves is controlled, the gap size of the micro-channels formed between the matching surfaces can be ensured, and compared with the type of grooves opened on the same surface, the processing difficulty of the present application is low, because the more grooves are opened, the smaller the interval between the grooves is, and the higher the requirement for processing technology and equipment is.

[0025] Meanwhile, the ordinary micro-channel cooling heat sink is cooled by the cooling liquid flowing in the micro-channels, and in addition to this, the second heat dissipation ribs 6 and the first heat dissipation grooves 7 are in contact and abutment through the heat-conducting metal filling layer 4, which can further improve the heat exchange efficiency, and the following technical solutions are adopted: the height of the second heat dissipation ribs 6 is greater than the height of the first heat dissipation ribs 5, the end of the second heat dissipation ribs 6 abuts against the groove bottom of the first heat dissipation grooves 7, and preferably, the difference between the height of the second heat dissipation ribs 6 and the height of the first heat dissipation ribs 5 is 0.3 mm; and in order to improve the cooling uniformity, the difference between the height of the second heat dissipation ribs 6 and the height of the first heat dissipation ribs 5 is half the width difference between the first heat dissipation grooves 7 and the second heat dissipation ribs 6, so that the width of the formed micro-channels remains consistent.

[0026] The micro-channel heat sink working end 1 of the present application adopts a high thermal conductivity metal material with a thermal expansion coefficient close to that of the laser gain medium, the material of the micro-channel heat dissipation reinforcing end 2 is the same as that of the micro-channel heat sink working end 1; the heat-conducting metal filling layer adopts a 10 μm gold plating layer or a 10 μm indium foil layer.

[0027] A specific laser cooling heat sink parameter is provided as follows:

[0028] Implementation 1

[0029] The micro-channel heat sink working end 1, the heat-conducting metal filling layer 4, the micro-channel heat dissipation reinforcing end 2 and the heat sink base 3, the whole micro-channel structure laser cooling heat sink is used for cooling the sheet structure Nd:YAG laser gain medium, and the temperature control requirement of the laser with the highest 500W average output power can be realized (the laser ambient temperature is 23℃, the optimal working temperature of the gain medium is 28℃, and the maximum temperature rise of the laser crystal is 5℃).

[0030] The micro-channel heat sink working end 1 is made of 85 copper tungsten alloy, with the size of 45×60×8mm, and the stress-free welding of the working surface of the micro-channel heat sink working end 1 is 42×50×10mm Nd:YAG laser crystal, the micro-channel heat sink working end 1 heat dissipation surface micro-channel groove width is 0.5mm, the groove depth is 6mm, and the rib thickness is 0.25mm; the heat-conducting metal filling layer 2 is made of 10μm indium foil layer; the micro-channel heat dissipation reinforcing end 2 is made of 85 copper tungsten alloy, with the size of 65×80×20mm.

[0031] The above only is the preferred embodiment of the present application, it should be pointed out: for the ordinary skilled in the art, without departing from the principles of the present application, can also make a number of improvements and refinements, these improvements and refinements should also be considered as the protection scope of the present application.

Claims

1. A laser cooling heat sink having a microchannel structure, characterized by, The micro-channel heat sink includes a working end (1), a heat dissipation reinforcing end (2) and a heat sink base (3), the working end (1) and the heat dissipation reinforcing end (2) are sequentially arranged in the heat sink base (3), the working surface of the working end (1) is attached to the cooling surface of the laser crystal, and the cooperation surface between the working end (1) and the heat dissipation reinforcing end (2) is pressed to form the micro-channel structure through the staggered heat dissipation ribs, the heat sink base (3) is provided with an inlet hole and an outlet hole which are communicated with the micro-channel structure; The micro-channel structure includes first heat dissipation ribs (5) arranged on the heat dissipation surface of the working end (1) and second heat dissipation ribs (6) arranged on the heat dissipation reinforcing end (2), the first heat dissipation ribs (5) are arranged in the first heat dissipation grooves (7) with the same height as the first heat dissipation ribs (5), the second heat dissipation ribs (6) are arranged in the second heat dissipation grooves (8) with the same height as the second heat dissipation ribs (6), the width of the first heat dissipation grooves (7) is greater than or equal to the width of the second heat dissipation grooves (8), the width of the second heat dissipation grooves (8) is greater than the width of the first heat dissipation ribs (5), the first heat dissipation ribs (5) and the second heat dissipation ribs (6) are staggered, the first heat dissipation ribs (5) are inserted into the second heat dissipation grooves (8), and the second heat dissipation ribs (6) are inserted into the first heat dissipation grooves (7), the micro-channels (9) for the flow of the cooling liquid are formed between the first heat dissipation ribs (5) and the second heat dissipation grooves (8) and between the second heat dissipation ribs (6) and the first heat dissipation grooves (7); The height of the second heat dissipation ribs (6) is greater than the height of the first heat dissipation ribs (5), the end of the second heat dissipation ribs (6) is abutted with the groove bottom of the first heat dissipation grooves (7) through the heat-conducting metal filling layer (4), the difference between the height of the second heat dissipation ribs (6) and the height of the first heat dissipation ribs (5) is 0.3mm, and the heat-conducting metal filling layer (4) is a 10μm gold plating layer or a 10μm indium foil layer.

2. The laser cooling heat sink with microchannel structure according to claim 1, wherein, The width of the first heat dissipation ribs (5) is half of the width of the first heat dissipation grooves (7), the width of the second heat dissipation ribs (6) is half of the width of the second heat dissipation grooves (8), and the width of the first heat dissipation ribs (5) is equal to the width of the second heat dissipation ribs (6).

3. The laser cooling heat sink with microchannel structure of claim 1, wherein, The working end (1) is made of a high-thermal-conductivity metal material with a thermal expansion coefficient close to that of the laser gain medium, and the material of the heat dissipation reinforcing end (2) is the same as that of the working end (1).

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