Preparation process of protective shell for heat dissipation of mobile phone and computer

Abstract

The invention discloses a preparation process of a protective shell for heat dissipation of a mobile phone and a computer. The preparation process comprises the following steps: S1, firstly, preparing raw materials; s2, mixing the raw materials; s3, processing and forming the mixed material; s4, carrying out high-temperature sintering on the molded product, and then carrying out surface treatment on the product; s5, testing the heat dissipation performance of the product; and S6, finished products which are tested to be qualified and plastic and hardware structures are designed and molded into the mobile phone and computer protection shell. The high-performance graphene aluminum material is prepared by combining the aluminum powder and the graphene powder, and the heat conductivity coefficient of the material is within the range of 335 W / mK to 350 W / mK through the preparation process of the scheme, so that after the protective shell is prepared from the material, the protective shell has better heat conductivity, and the service life of the protective shell is prolonged. Therefore, the protective shell prepared from the aluminum material can protect electronic products such as mobile phones, and also can guarantee heat dissipation of the electronic products.

Description

Technical Field

[0001] The present invention relates to the technical field of heat dissipation of electronic equipment, and in particular to a process for preparing a protective shell for heat dissipation of mobile phones and computers. Background Art

[0002] With the continuous updating and iteration of electronic products, their functions are becoming more and more powerful, especially mobile phones and computers can be seen everywhere in people's daily lives. In the process of using these electronic devices, their internal CPUs and electronic components will release heat when they are running. If this heat is not discharged in time, it will affect the continued stable use of the CPU and electronic components.

[0003] When existing mobile phones and computers are in use, protective shells are placed on the outside of these electronic devices for protection. Since electronic devices such as mobile phones and computers are mostly cooled by the back shell when in use, and the protective shell will cover the back cover of the device, and the existing protective shell structure does not have the function of heat dissipation due to material design, the heat dissipation of the electronic device will be affected when the protective shell is used. Therefore, this scheme proposes a preparation process of a protective shell for heat dissipation of mobile phones and computers to solve the above problem. Summary of the invention

[0004] The purpose of the present invention is to provide a process for preparing a protective shell for heat dissipation of mobile phones and computers, so as to solve the problems raised in the above-mentioned background technology.

[0005] To achieve the above object, the present invention provides the following technical solution: a preparation process of a protective shell for heat dissipation of mobile phones and computers, the preparation process comprising the following steps:

[0006] S1, firstly preparing raw materials, wherein the raw materials include graphene powder, aluminum powder and additives, and performing pretreatment after the raw materials are prepared;

[0007] S2, mixing the raw materials, firstly, putting the aluminum powder in the raw materials into a high temperature furnace, heating it to a molten state at a temperature of 700°C-800°C, then adding the graphene in the raw materials into the molten aluminum liquid and stirring and mixing, and finally adding the additives and stirring and mixing;

[0008] S3, processing and molding the mixed material, pouring the mixed molten metal into a mold for casting;

[0009] S4, high temperature sintering of the formed product, and then surface treatment of the product;

[0010] S5, conduct product heat dissipation performance test, use laser flash method to test whether the thermal conductivity of the product is in the range of 335W / mK-350W / mK, if yes, then the finished product is produced, if not, the material is recycled;

[0011] S6, the finished products that have passed the test are combined with plastic and hardware structure design to form mobile phone and computer protective cases.

[0012] Preferably, the additives in S1 include carbon nanotubes, aluminates, surfactants and phosphites.

[0013] Preferably, the pretreatment of the raw materials in S1 is a dispersion treatment of graphene powder, comprising the following steps:

[0014] A1, firstly sieving the graphene powder, placing the graphene powder under a 2000-3000 mesh sieve for sieving, and collecting the sieved graphene powder;

[0015] A2, putting graphene powder into water, and then using an ultrasonic cleaning machine to perform ultrasonic treatment for 30min-60min to obtain a dispersed liquid;

[0016] A3, centrifuging the dispersed liquid obtained in A2 using a centrifuge to remove undispersed particles;

[0017] A4, removing the dispersed liquid after centrifugation in A3 by vacuum drying to obtain dry graphene powder.

[0018] Preferably, during the heating of the aluminum powder in S2, a thermometer is used to monitor the temperature of the aluminum liquid to ensure that the heating temperature is 700°C-800°C, and the aluminum liquid is stirred at a speed of 40-60r / min during the heating process.

[0019] Preferably, the weight ratio of the graphene powder in S2 added to the molten aluminum liquid is 1% to 5%.

[0020] Preferably, after the graphene powder is added, it is stirred using a high shear stirrer, the stirring speed is 500r / min-1000r / min, and the stirring time is 10min-30min.

[0021] Preferably, after the S2 graphene powder is mixed with the molten aluminum liquid, an additive is added and stirred at a speed of 500r / min-800r / min for 10min-15min.

[0022] Preferably, the mixed molten metal in S3 is poured into the mold by pouring, and is oscillated to exhaust air, so as to remove bubbles in the molten metal in the mold, and then the casting is performed by gravity casting.

[0023] Preferably, the high temperature sintering in S4 is performed by placing the cast product into a high temperature furnace at a temperature of 300°C-600°C.

[0024] Preferably, the product is cooled to room temperature after sintering and then cut, polished and sprayed.

[0025] Technical effects and advantages of the present invention:

[0026] The present invention prepares a high-performance graphene aluminum material by combining aluminum powder and graphene powder. Through the preparation process of the present scheme, the thermal conductivity of the material is in the range of 335W / mK-350W / mK. Therefore, after using the present material to prepare a protective shell, the protective shell can have better thermal conductivity. In this way, the protective shell prepared by the present aluminum material can protect mobile phone electronic products while ensuring their heat dissipation. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is an operation flow chart of the preparation process of the present invention. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] The present invention provides Figure 1 The process for preparing a protective shell for heat dissipation of mobile phones and computers shown includes the following steps:

[0030] S1, firstly prepare the raw materials, which include graphene powder, aluminum powder and additives, and then perform pretreatment after the raw materials are prepared;

[0031] Specifically, the additives in S1 include carbon nanotubes, aluminate, surfactant and phosphite.

[0032] It should be noted that carbon nanotubes are a nanoscale tubular structure composed of carbon atoms arranged in a hexagonal shape, which has excellent mechanical strength and thermal conductivity. When combined with graphene, it can further improve the overall performance of the heat dissipation material; aluminates are a class of compounds containing aluminum and acid ions, which can improve the strength and durability of the material. When combined with graphene, they can improve the thermal conductivity and antioxidant properties of the composite material; surfactants are a class of substances that can reduce the surface tension of liquids, which can help improve the interaction between different substances, and are used to improve the compatibility between graphene and aluminum, and enhance the uniformity and stability of the composite material; phosphites are a class of compounds containing phosphite ions, which can improve the thermal stability and antioxidant properties of the material. This material is a high-performance graphene aluminum alloy casting material, and the goal is to replace copper with high thermal conductivity graphene aluminum.

[0033] Specifically, the pretreatment of the raw materials in S1 is the dispersion treatment of graphene powder, which includes the following steps:

[0034] A1, firstly sieving the graphene powder, placing the graphene powder under a 2000-3000 mesh sieve for sieving, and collecting the sieved graphene powder;

[0035] It should be noted that graphene can be prepared by chemical vapor deposition (CVD) or liquid phase exfoliation. After the graphene powder is sieved out through a 2000-3000 mesh sieve, the small particle size of the graphene powder is ensured to facilitate subsequent dispersion.

[0036] A2, putting graphene powder into water, and then using an ultrasonic cleaning machine to perform ultrasonic treatment for 30min-60min to obtain a dispersed liquid;

[0037] It should be noted that this step is to disperse the graphene powder. Water is used as a solvent for dispersing the graphene powder. Ethanol can also be used as a solvent. After ultrasonic treatment, the graphene powder can be dispersed more evenly.

[0038] A3, centrifuging the dispersed liquid obtained in A2 using a centrifuge to remove undispersed particles;

[0039] It should be noted that the graphene clusters that are not dispersed into clusters are removed by centrifugation.

[0040] A4, removing the dispersed liquid after centrifugation in A3 by vacuum drying to obtain dry graphene powder.

[0041] S2, mixing the raw materials, firstly, putting the aluminum powder in the raw materials into a high temperature furnace, heating it to a molten state at a temperature of 700°C-800°C, then adding the graphene in the raw materials into the molten aluminum liquid and stirring and mixing, and finally adding the additives and stirring and mixing;

[0042] Specifically, during the heating process of the aluminum powder in S2, a thermometer is used to monitor the temperature of the aluminum liquid to ensure that the heating temperature is between 700°C and 800°C, and the aluminum liquid is stirred at a speed of 40-60r / min during the heating process.

[0043] It should be noted that the aluminum powder is heated to a molten state at a temperature of 700° C. to 800° C., and the temperature is measured with a thermometer during the heating and stirring process to ensure that it is within a set range.

[0044] Furthermore, the weight ratio of graphene powder added to the molten aluminum liquid in S2 is 1% to 5%. After the graphene powder is added, it is stirred using a high shear stirrer with a stirring speed of 500r / min-1000r / min and a stirring time of 10min-30min.

[0045] It should be noted that when fusing graphene powder and molten aluminum, dry and evenly dispersed graphene powder is added while stirring, so as to ensure that the graphene is more fully dispersed in the molten aluminum. High shear mixer is a device used for mixing, emulsifying, dispersing and refining materials. Its main principle is to generate strong shear force through high-speed rotating blades or rotors to effectively mix and process materials in a short time. It can quickly and evenly mix materials of different viscosities and densities, and can adjust the speed and stirring time as needed to meet different process requirements.

[0046] Furthermore, after the S2 graphene powder is mixed with the molten aluminum liquid, the additive is added and stirred at a speed of 500r / min-800r / min for 10min-15min.

[0047] It should be noted that the stability and thermal conductivity of the mixture of graphene powder and molten aluminum are increased by the incorporation of different types of additives, and a given heating temperature is required during the process of adding and stirring the additives to avoid solidification of the mixture of molten aluminum and graphene powder, ensuring that the additives are mixed more evenly.

[0048] S3, processing and molding the mixed material, pouring the mixed molten metal into a mold for casting;

[0049] Specifically, the mixed molten metal in S3 is poured into the mold and exhausted by shaking to remove bubbles in the molten metal in the mold, and then the casting is performed by gravity casting.

[0050] It should be noted that a release agent can be applied when pouring the molten metal into the mold, so that demolding can be carried out more conveniently after the product is cast. The molten metal needs to be poured slowly to avoid bubbles and ensure the stability of product casting. After casting, the cooling rate is controlled, usually naturally cooled at room temperature, to avoid cracks caused by too rapid cooling. The casting can be placed in a cooling box to control the cooling environment, including atmosphere and temperature.

[0051] S4, high temperature sintering of the formed product, and then surface treatment of the product;

[0052] Specifically, the high temperature sintering in S4 is to place the cast product into a high temperature furnace at a temperature of 300°C-600°C to enhance the bonding strength and thermal conductivity of the material.

[0053] Furthermore, after the product is sintered, it is cooled to room temperature and then cut, polished and sprayed.

[0054] It should be noted that the cast graphene aluminum sheet is cut, polished and machined to prepare the protective shell parts of the required shape. This step can use CNC processing and laser cutting technology to ensure dimensional accuracy and surface finish. The surface of the protective shell can be coated, including spraying and anodizing, to improve wear resistance and aesthetics. After that, the surface smoothness can be improved through a polishing process to further enhance the heat dissipation performance.

[0055] S5, conduct product heat dissipation performance test, use laser flash method to test whether the thermal conductivity of the product is in the range of 335W / mK-350W / mK, if yes, then the finished product is produced, if not, the material is recycled;

[0056] It should be noted that the laser flash method is a technology used for testing and analyzing material properties, especially in the measurement of thermal properties and thermal conductivity. The basic principle of this method is to use laser to instantaneously irradiate the sample surface to generate a heat pulse, and then deduce the material's thermal physical properties, including thermal diffusivity and thermal conductivity, by measuring the change in sample surface temperature over time. The basic steps of the laser flash method are:

[0057] Laser irradiation, which applies a high-intensity laser beam to the sample surface to generate an instantaneous heat pulse;

[0058] Temperature measurement, using thermocouples, infrared cameras or other temperature sensors to monitor the change in sample surface temperature over time;

[0059] Data analysis, based on the time series data of temperature changes, the heat conduction theory model is applied to calculate the thermal physical properties of the sample.

[0060] Its advantages include: laser irradiation does not contact the sample, thus avoiding physical damage to the sample; it can accurately measure the instantaneous thermal response of the material, and is suitable for testing high and low thermal conductivity materials; it can be used for thermal property testing of solids, liquids and certain gases.

[0061] S6, combines the qualified finished products with plastic and hardware structure design to form mobile phone and computer protective cases, successfully adding graphene evenly into liquid aluminum, increasing the thermal conductivity of aluminum from 220W / mK to 350W / mK, close to copper's 385W / mK.

[0062] Example 1: The high-performance graphene aluminum alloy molten casting material prepared by the above process was subjected to chemical composition detection and mechanical property testing. The test results are shown in Table 1 below;

[0063] Table 1

[0064]

[0065]

[0066] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A process for preparing a protective shell for heat dissipation of mobile phones and computers, characterized in that: The preparation process comprises the following steps: S1, firstly preparing raw materials, wherein the raw materials include graphene powder, aluminum powder and additives, and performing pretreatment after the raw materials are prepared; S2, mixing the raw materials, firstly, putting the aluminum powder in the raw materials into a high temperature furnace, heating it to a molten state at a temperature of 700°C-800°C, then adding the graphene in the raw materials into the molten aluminum liquid and stirring and mixing, and finally adding the additives and stirring and mixing; S3, processing and molding the mixed material, pouring the mixed molten metal into a mold for casting; S4, high temperature sintering of the formed product, and then surface treatment of the product; S5, conduct product heat dissipation performance test, use laser flash method to test whether the thermal conductivity of the product is in the range of 335W / mK-350W / mK, if yes, then the finished product is produced, if not, the material is recycled; S6, the finished products that have passed the test are combined with plastic and hardware structure design to form mobile phone and computer protective cases.

2. A process for preparing a protective shell for heat dissipation of mobile phones and computers according to claim 1, characterized in that: The additives in S1 include carbon nanotubes, aluminate, surfactant and phosphite.

3. A process for preparing a protective shell for heat dissipation of mobile phones and computers according to claim 1, characterized in that: The pretreatment of the raw materials in S1 is the dispersion treatment of graphene powder, which includes the following steps: A1, firstly sieving the graphene powder, placing the graphene powder under a 2000-3000 mesh sieve for sieving, and collecting the sieved graphene powder; A2, putting graphene powder into water, and then using an ultrasonic cleaning machine to perform ultrasonic treatment for 30min-60min to obtain a dispersed liquid; A3, centrifuging the dispersed liquid obtained in A2 using a centrifuge to remove undispersed particles; A4, removing the dispersed liquid after centrifugation in A3 by vacuum drying to obtain dry graphene powder.

4. A process for preparing a protective shell for heat dissipation of mobile phones and computers according to claim 1, characterized in that: During the heating process of the aluminum powder in S2, a thermometer is used to monitor the temperature of the aluminum liquid to ensure that the heating temperature is 700°C-800°C, and stirring is performed at a speed of 40-60r / min during the heating process.

5. A process for preparing a protective shell for heat dissipation of mobile phones and computers according to claim 1, characterized in that: The weight ratio of the graphene powder in S2 added to the molten aluminum liquid is 1% to 5%.

6. A process for preparing a protective shell for heat dissipation of mobile phones and computers according to claim 5, characterized in that: After the graphene powder is added, it is stirred using a high shear stirrer at a stirring speed of 500 r / min-1000 r / min and a stirring time of 10 min-30 min.

7. A process for preparing a protective shell for heat dissipation of mobile phones and computers according to claim 1, characterized in that: After the S2 graphene powder is mixed with the molten aluminum liquid, the additive is added and stirred at a speed of 500r / min-800r / min for 10min-15min.

8. The process for preparing a protective shell for heat dissipation of mobile phones and computers according to claim 1, characterized in that: When the mixed molten metal in S3 is poured into the mold, it is poured and oscillated to exhaust air, so as to remove bubbles in the molten metal in the mold, and then the casting is performed by gravity casting.

9. A process for preparing a protective shell for heat dissipation of mobile phones and computers according to claim 1, characterized in that: The high temperature sintering in S4 is performed by placing the cast product into a high temperature furnace at a temperature of 300°C-600°C.

10. A process for preparing a protective shell for heat dissipation of mobile phones and computers according to claim 9, characterized in that: After the product is sintered, it is cooled to room temperature and then cut, polished and sprayed.

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