Cooling fin laser welding process

Abstract

The invention relates to the technical field of cooling fin production, in particular to a cooling fin laser welding process which comprises the following steps that a punching machine is used for punching an aluminum plate to form cooling fins, and the cooling fins are cleaned; forging the aluminum plate into a radiating fin base by using a forging press, and grinding and cleaning the base; combining the cleaned radiating fins with the base to form a plurality of laser welding areas; and the laser welding area is welded through a laser welding machine, and anodic oxidation treatment is conducted on a welded finished product. According to the cooling fin laser welding technology, the influence of high temperature can be avoided, machining is free of pollution, and efficiency is high.

Description

Technical Field

[0001] The invention relates to the technical field of heat sink production, and in particular to a heat sink laser welding process. Background Art

[0002] As the power density of electronic equipment continues to increase, heat dissipation has become a key factor restricting the performance and reliability of equipment. The heat sink fins and the bottom plate are welded together by high-temperature melting and solidification of solder paste. When the ambient temperature is higher than 120°C, the performance of the solder paste will fail. In addition, the traditional reflow soldering heat sink must be surface treated and electroplated before it can be welded with solder paste and flux. Solder paste and flux are required, and some flux will remain after welding. The welded product needs to be cleaned twice, and the power consumption is high during processing, and the processing efficiency is low. Summary of the invention

[0003] In order to overcome the shortcomings and deficiencies in the prior art, the purpose of the present invention is to provide a heat sink laser welding process, which can be used in scenarios that are not affected by high temperatures, and has no pollution and high efficiency.

[0004] The present invention is achieved through the following technical solutions:

[0005] In a first aspect, the present invention discloses a heat sink laser welding process, which comprises the following steps:

[0006] Use a punching machine to punch out heat sink fins from aluminum plates, and then clean the heat sink fins;

[0007] The aluminum sheet is forged into a base by a forging press, and the base is ground and cleaned;

[0008] Assemble the cleaned heat sink fins with the base to form several laser welding areas;

[0009] The laser welding area is welded by a laser welding machine, and the finished product after welding is anodized.

[0010] In combination with the first aspect, further, the punching force of the punching machine is calculated according to the physical characteristics of the aluminum plate, and the cleaning effect of the heat sink fin is evaluated according to the residual amount of surface pollutants;

[0011] The calculation formula of the punching force of the punching machine is:

[0012] F=k1·L·h·σ b

[0013] The calculation formula for evaluating the cleaning effect of the heat sink fins is:

[0014]

[0015] Among them, k1 is the metal tensile constant, L is the stamping circumference, h is the thickness of the aluminum sheet, σ b is the compressive strength of the material, C0 is the initial amount of contaminants, W0 is the initial weight of the sample before cleaning, and W1 is the weight of the sample after cleaning.

[0016] In combination with the first aspect, further, the forging pressure of the forging press is calculated according to the physical characteristics of the aluminum plate, and the cleaning effect of the base is evaluated according to the surface roughness;

[0017] The calculation formula for the forging pressure of the forging press is:

[0018] P=A a ·σ f

[0019] The calculation formula for evaluating the cleaning effect of the base is:

[0020]

[0021] Among them, A a is the forging area, σ f is the flow stress of the material, R a0 is the surface roughness before cleaning, R a It is the surface roughness after cleaning.

[0022] In combination with the first aspect, further, the output power of the laser welding machine is calculated according to the welding area, and the calculation formula of the output power of the laser welding machine is:

[0023]

[0024] Where M is the laser energy density, v is the average welding speed of the laser welding machine, A b is the welding area. In combination with the first aspect, further, the calculation formula for the thickness of the oxide film after anodizing treatment is:

[0025] d=k2·I·t

[0026] Among them, k2 is the oxidation coefficient efficiency, I is the current density, and t is the oxidation time.

[0027] In combination with the first aspect, further, the oxidation effect of the finished product is evaluated according to the thickness of the oxide film, and the calculation formula of the oxidation effect is:

[0028]

[0029] Among them, C r is the corrosion resistance of the finished product, d0 is the oxide film thickness required by the design, C r0 Corrosion resistance as required by design.

[0030] In a second aspect, the present invention further discloses an electronic device, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the heat sink laser welding process as described above.

[0031] In a third aspect, the present invention further discloses a computer-readable storage medium having a computer program stored thereon, wherein the program is executed by a processor to implement the heat sink laser welding process as described above.

[0032] Beneficial effects of the present invention:

[0033] The present invention provides a heat sink laser welding process, electronic device and storage medium. The laser welding area of ​​the heat sink fin and the base is heated by laser to melt the material to form a molten pool. The heat sink fin and the base welding point are integrated and are not affected by high temperature. The heat sink fin and the base welding point can be applied to any high-temperature heat dissipation scenario. In addition, direct welding of aluminum saves electroplating costs, and laser welding is clean, pollution-free and efficient. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The present invention is further described using the accompanying drawings, but the embodiments in the accompanying drawings do not constitute any limitation to the present invention. A person skilled in the art can obtain other drawings based on the following drawings without creative work.

[0035] Figure 1 A flow chart of the steps of the heat sink laser welding process provided by an embodiment of the present invention. Figure 2 This is a comparative test diagram of the reflow soldering sample and the laser soldering sample provided in the embodiment of the present invention. DETAILED DESCRIPTION

[0036] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific embodiments disclosed below.

[0037] As the power density of electronic devices continues to increase, heat dissipation becomes a key factor restricting the performance and reliability of equipment. The heat sink fins and the bottom plate are welded together by high-temperature melting and solidification of solder paste. When the ambient temperature is higher than 130°C, the performance of the solder paste will fail. In addition, the traditional reflow soldering process requires the use of solder paste and flux. After soldering, some flux will remain, and the soldered products need to be cleaned twice. In addition, the power consumption during processing is large and the processing efficiency is low.

[0038] In order to solve the above problems, this embodiment discloses a heat sink laser welding process, which includes the following steps:

[0039] Use a punching machine to punch out heat sink fins from aluminum plates, and then clean the heat sink fins;

[0040] The aluminum sheet is forged into a base by a forging press, and the base is ground and cleaned;

[0041] Assemble the cleaned heat sink fins with the base to form several laser welding areas;

[0042] The laser welding area is welded by a laser welding machine, and the finished product after welding is anodized.

[0043] Furthermore, the punching force of the punching machine is calculated based on the physical characteristics of the aluminum sheet, and the cleaning effect of the heat sink fins is evaluated based on the residual amount of surface contaminants;

[0044] The calculation formula of the punching force of the punching machine is:

[0045] F=k1·L·h·σ b

[0046] The calculation formula for evaluating the cleaning effect of the heat sink fins is:

[0047]

[0048] Among them, k1 is the metal tensile constant, L is the stamping circumference, h is the thickness of the aluminum sheet, σ b is the compressive strength of the material, C0 is the initial amount of contaminants, W0 is the initial weight of the sample before cleaning, and W1 is the weight of the sample after cleaning.

[0049] Furthermore, the forging force of the forging press is calculated based on the physical characteristics of the aluminum sheet, and the cleaning effect of the base is evaluated based on the surface roughness;

[0050] The calculation formula for the forging pressure of the forging press is:

[0051] P=A a ·σ f

[0052] The calculation formula for evaluating the cleaning effect of the base is:

[0053]

[0054] Among them, A a is the forging area, σ f is the flow stress of the material, R a0 is the surface roughness before cleaning, R a It is the surface roughness after cleaning.

[0055] Furthermore, the output power of the laser welding machine is calculated according to the welding area. The calculation formula of the output power of the laser welding machine is:

[0056]

[0057] Where M is the laser energy density, v is the average welding speed of the laser welding machine, A b is the welding area. Further, the calculation formula for the thickness of the oxide film after anodizing treatment is:

[0058] d=k2·I·t

[0059] Among them, k2 is the oxidation coefficient efficiency, I is the current density, and t is the oxidation time.

[0060] Furthermore, the oxidation effect of the finished product is evaluated according to the thickness of the oxide film. The calculation formula for the oxidation effect is:

[0061]

[0062] Among them, C r is the corrosion resistance of the finished product, d0 is the oxide film thickness required by the design, C r0 Corrosion resistance as required by design.

[0063] Specifically, the heat sink laser welding process of this embodiment has the following beneficial effects:

[0064] 1. The traditional reflow soldering process relies on the solder paste to melt at high temperature and then solidify and weld together. When the ambient temperature is higher than 130°C, the solder paste performance will fail. Laser welding heats the laser welding area of ​​the heat sink fins and the base through laser pulses to melt the material to form a molten pool. The heat sink fins and the base solder joints are integrated and are not affected by high temperatures. It can be used in any high-temperature heat dissipation scenario.

[0065] 2. The heat sink laser welding process solves the problem that traditional reflow soldering process products cannot be welded without electroplating. Direct welding of aluminum saves electroplating costs, accounting for about 12% of the total cost, and is highly efficient and pollution-free.

[0066] 3. Traditional reflow soldering requires the use of solder paste and flux. Some flux will remain after soldering, and the soldered products need to be cleaned twice. There will be waste gas from soldering, and industrial cleaning fluid will need to be handled during cleaning. Laser welding is clean and pollution-free.

[0067] 4. The traditional reflow soldering solder paste is baked in a high-temperature tunnel furnace, which consumes a lot of power during processing, consuming 80KW per hour. Laser welding consumes 3KW per hour and has low energy consumption;

[0068] 5. Traditional reflow soldering requires the use of solder paste / flux, while laser soldering directly solders without the use of solder paste, saving costs by more than 2.5%;

[0069] 6. Laser welding of heat sinks is highly efficient, with laser welding taking 1 PCS / 0.15 minutes; the traditional high-temperature furnace reflow welding takes 1 PCS / 8 minutes;

[0070] 7. The heat dissipation effect of laser welding and reflow solder paste welding heat sink is the same, and the heat dissipation effect is better than the traditional solder paste welding process. For comparison, refer to Figure 2 , where CASE1 is a reflow soldering sample and CASE2 is a laser welding sample.

[0071] Some embodiments of the present application also provide an electronic device, comprising: a processor, a memory, a bus and a communication interface, wherein the processor, the communication interface and the memory are connected via a bus; the memory stores a computer program that can be run on the processor, and when the processor runs the computer program, it executes the method provided in any of the aforementioned embodiments of the present application.

[0072] The memory may include high-speed random access memory (RAM), and may also include non-volatile memory, such as at least one disk memory. The communication connection between the system network element and at least one other network element is realized through at least one communication interface (which may be wired or wireless), and the Internet, wide area network, local area network, metropolitan area network, etc. may be used.

[0073] The bus may be an ISA bus, a PCI bus or an EISA bus, etc. The bus may be divided into an address bus, a data bus, a control bus, etc. The memory is used to store a program, and the processor executes the program after receiving an execution instruction. The heat sink laser welding process disclosed in any implementation of the above-mentioned embodiment of the present application may be applied to the processor, or implemented by the processor.

[0074] The processor may be an integrated circuit chip with signal processing capabilities. In the implementation process, each step of the above method can be completed by an integrated logic circuit of hardware in the processor or an instruction in the form of software. The above processor may be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it may also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a readily available programmable gate array (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components. The methods, steps and logic block diagrams disclosed in the embodiments of the present application can be implemented or executed. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc. The steps of the method disclosed in the embodiments of the present application can be directly embodied as a hardware decoding processor to be executed, or a combination of hardware and software modules in the decoding processor to be executed. The software module may be located in a mature storage medium in the field such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory or an electrically erasable programmable memory, a register, etc. The storage medium is located in a memory, and the processor reads the information in the memory and completes the steps of the above method in combination with its hardware.

[0075] The electronic device provided in the embodiment of the present application and the image preprocessing method provided in the embodiment of the present application are based on the same application concept and have the same beneficial effects as the methods adopted, operated or implemented therein.

[0076] Some embodiments of the present application also provide a computer-readable storage medium corresponding to the image preprocessing method provided in the aforementioned embodiments, on which a computer program is stored. The computer-readable storage medium is a CD, on which a computer program (i.e., a program product) is stored. When the computer program is run by a processor, it will execute the image preprocessing method provided in any of the aforementioned embodiments.

[0077] It should be noted that examples of the computer-readable storage medium may also include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other optical or magnetic storage media, which are not listed here one by one.

[0078] The computer-readable storage medium provided in the above-mentioned embodiments of the present application and the heat sink laser welding process provided in the embodiments of the present application are based on the same application concept and have the same beneficial effects as the methods adopted, run or implemented by the application programs stored therein.

[0079] It should be noted that: in the above text, the term "comprises", "includes" or any other variant thereof is intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "including one..." do not exclude the presence of other identical elements in the process, method, article or device including the element. In addition, it should be pointed out that the scope of the method and device in the embodiment of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in the opposite order according to the functions involved, for example, the described method may be performed in an order different from that described, and various steps may also be added, omitted, or combined. In addition, the features described with reference to certain examples may be combined in other examples.

[0080] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, a magnetic disk, or an optical disk), and includes a number of instructions for a terminal (which can be a mobile phone, a computer, a server, an air conditioner, or a network device, etc.) to execute the methods described in each embodiment of the present application.

[0081] The embodiments of the present application are described above in conjunction with the accompanying drawings, which are only specific implementation modes of the present application. However, the present application is not limited to the above-mentioned specific implementation modes. The above-mentioned specific implementation modes are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.

Claims

1. A heat sink laser welding process, characterized in that: The following steps are involved: Use a punching machine to punch out heat sink fins from aluminum plates, and then clean the heat sink fins; The aluminum sheet is forged into a base by a forging press, and the base is ground and cleaned; Assemble the cleaned heat sink fins with the base to form several laser welding areas; The laser welding area is welded by a laser welding machine, and the finished product after welding is anodized.

2. A heat sink laser welding process according to claim 1, characterized in that: Calculate the punching force of the punching machine based on the physical characteristics of the aluminum sheet, and evaluate the cleaning effect of the heat sink fins based on the residual amount of surface contaminants; The calculation formula of the punching force of the punching machine is: F=k1·L·h·σ b The calculation formula for evaluating the cleaning effect of the heat sink fins is: Among them, k1 is the metal tensile constant, L is the stamping circumference, h is the thickness of the aluminum sheet, σ b is the compressive strength of the material, C0 is the initial amount of contaminants, W0 is the initial weight of the sample before cleaning, and W1 is the weight of the sample after cleaning.

3. The heat sink laser welding process according to claim 1, characterized in that: The forging force of the forging press is calculated based on the physical characteristics of the aluminum sheet, and the cleaning effect of the base is evaluated based on the surface roughness; The calculation formula for the forging pressure of the forging press is: P=A a ·s f The calculation formula for evaluating the cleaning effect of the base is: Among them, A a is the forging area, σ f is the flow stress of the material, R a0 is the surface roughness before cleaning, R a It is the surface roughness after cleaning.

4. The heat sink laser welding process according to claim 1, characterized in that: The output power of the laser welding machine is calculated according to the welding area. The calculation formula for the output power of the laser welding machine is: Where M is the laser energy density, v is the average welding speed of the laser welding machine, A b is the welding area.

5. The heat sink laser welding process according to claim 1, characterized in that: The calculation formula for the thickness of the oxide film after anodizing treatment is: d=k2·I·t Among them, k is the oxidation coefficient efficiency, I is the current density, and t is the oxidation time.

6. A heat sink laser welding process according to claim 5, characterized in that: The oxidation effect of the finished product is evaluated according to the thickness of the oxide film. The calculation formula for the oxidation effect is: Among them, C r is the corrosion resistance of the finished product, d0 is the oxide film thickness required by the design, C r0 Corrosion resistance as required by design.

7. An electronic device, characterized in that: The invention comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the heat sink laser welding process as claimed in any one of claims 1 to 6.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that: The program is executed by a processor to implement the heat sink laser welding process according to any one of claims 1 to 6.

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