What is used to cut graphite sheets? Precision laser cutting machine!

Although thermally conductive graphite sheets are increasingly used in various industries, they are facing more and more challenges. As electronic products become smaller and smaller, chip sizes become smaller and smaller, and heat conduction becomes difficult. What should graphite sheets be cut with?

The thermally conductive graphite sheet not only needs to improve the thermal conductivity and meet higher thermal conductivity requirements, but also needs to continuously improve the size, and the processing site is getting smaller and smaller. Whether the size meets the standard requirements is related to the cutting process of the thermally conductive graphite sheet.

The cutting process of thermally conductive graphite sheets is related to their actual application. There are two commonly used types at present: adhesive film and back film. Adhesive film cutting refers to the process of multi-back adhesive treatment on the surface of graphite sheets when cutting them, so that the graphite sheets have a certain adhesion. This bonding laser die-cutting can make the thermal conductive graphite sheets better bonded to the circuit board and better dissipate heat for electronic products. Sometimes, the size of the insulation and heat dissipation materials required for the circuit board is inconsistent with the size of the thermal conductive graphite sheet, so the back film of the graphite sheet group needs to be processed to make it more suitable for electronic products.

Currently, graphite sheet laser cutting machinelaser die-cutting machineor precision laser cutting machine. The graphite sheet laser cutting machine adopts the principle of laser cutting, which can quickly and effectively cut thermal conductive graphite sheets. Since the application of laser technology is relatively mature, this graphite sheet laser cutting machine can perform stable and long-term processing operations. However, due to the influence of the structure of the thermal conductive graphite sheet itself, the product is relatively brittle and its thickness cannot be cut too thin. Therefore, although the laser cutting machine can achieve thin cutting technology, it cannot immediately achieve a finer graphite sheet size. Experts need to first improve the performance of the graphite sheet.

Factors affecting the thermal conductivity of graphite sheets

Thermal conductive graphite sheet is a product made of natural graphene with good thermal conductivity. Sound is the main form of thermal conductivity of graphene. When this form of thermal conductivity changes, its thermal conductivity will change. According to people's research on thermal conductive graphite sheets, the thermal conductivity, size, temperature, thickness and dispersion of graphene will be affected, which are described in detail below.

Thermal conductive graphite sheet can provide a phonon propagation path along the direction of the graphene sheet. The filler has less contact with the polymer interface, the interface contact resistance is small, and the phonon scattering function at the edge of the graphene sheet is reduced, which is conducive to an effective thermal conductive network. Therefore, the thermal conductivity parallel to the direction of the graphene sheet is better than the thermal conductivity perpendicular to the graphene sheet. Due to different preparation processes, thermally conductive graphite sheets of different sizes and thicknesses will be obtained. Large graphite has a large specific surface area, which can reduce edge phonon scattering and is conducive to heat conduction. The smaller the thickness of the graphite sheet, the larger the specific surface area and the stronger the thermal conductivity. However, due to the limitations of the preparation process, it can only be 0.1mm at present, no matter how thin the thickness is, it cannot be made.

When the thermally conductive graphite sheet conducts heat, the change in temperature will also affect the thermal conductivity. After many tests, it was found that the thermal conductivity efficiency of 655鈩?graphite will increase with the increase of temperature, which is a limit value. When the temperature is lower than the temperature; when the temperature exceeds 655鈩? the thermal conductivity of graphite will decrease with the increase of temperature. However, when the graphene content in the thermally conductive graphite sheet increases, the decrease in thermal conductivity will slow down. People can choose different graphene-containing graphite sheets according to the needs of heat dissipation.

Thermal conductivity of graphite sheet

Thermal conductive graphite sheet is a very popular heat dissipation material widely used in electronic products. Graphite chemically becomes carbon element, with stable molecular structure and strong thermal conductivity. Thermal conductive graphite sheet also has strong thermal conductivity and electrical conductivity. The thermal conductivity of graphite sheets on the market is 150-150,000. According to people's test W/(m?K), the conductivity between them is much higher than other thermal conductive materials. The high conductivity of graphite is also used in the production of batteries, but its conductivity is not emphasized in thermal conductive products.

Thermal conductive graphite sheet also has the advantages of low thermal resistance, light weight, corrosion resistance and radiation resistance. The thermal resistance of graphite sheets is 40% lower than that of metal aluminum, 20% lower than that of metal copper, and 20% lower than that of copper; the weight of graphite sheets is 25% lighter than that of metal and 75% lighter than that of metal copper. Although the thermal conductivity of metal aluminum and copper sheets exceeds 20,000 W/(m?K), which is much higher than that of graphite, the above two points are relatively poor and are not as suitable as graphite for thermal conductive materials. When using thermal conductive graphite sheets in electronic products, there is no need to worry about the weight of the electronic products, nor do you have to worry about the corrosive substances of electronic components affecting their thermal conductivity.

Thermal conductive graphite sheets also have good compressibility, resilience and low stress creep rate, which are very suitable for sealing materials. According to the heat dissipation requirements of electronic products, graphite is made into thermal conductive sheets of different thicknesses and sizes, which can play a certain role in shockproofing electronic components on circuit boards and protect electronic components from thermal damage. Due to the characteristics of thermal conductive graphite sheets, it has become a mainstream thermal conductive product and has contributed to improving the performance of electronic products.