Views: 500 Author: Site Editor Publish Time: 2024-09-06 Origin: Site
The heat dissipation effect of thermal graphite sheet is affected in the following aspects.
1. The characteristics of the material:
- Purity of graphite: the higher the purity of graphite sheet, the better its thermal conductivity. If the graphite sheet contains impurities, it will affect the lattice structure of the graphite sheet and reduce its thermal conductivity efficiency. Therefore, in the production of thermal graphite sheets, it is necessary to use high purity graphite raw materials.
- The crystal structure of graphite: the crystal structure of graphite sheet has a great influence on its thermal conductivity. The graphite sheet with a good crystal structure has a regular arrangement of carbon atoms, which is conducive to heat conduction. For graphite sheet with more crystal structure defects, heat will be hindered in the conduction process, resulting in decreased thermal conductivity.
- Thickness of graphite sheet: In general, the thinner the thickness of graphite sheet, the better the heat dissipation effect. Because the thin graphite sheet can reduce the conduction resistance of heat in the vertical direction, improve the conduction efficiency of heat. However, the graphite sheet that is too thin has low mechanical strength and is easily damaged during use, so it is necessary to select the appropriate thickness of the graphite sheet according to the specific application scenario.
2. Production process:
- Hot pressing process: Hot pressing process is one of the key processes for the production of thermal graphite sheets. Parameters such as hot pressing temperature, pressure and time will affect the thermal conductivity of graphite sheet. If the hot pressing temperature is too high or the time is too long, it will cause the crystal structure of the graphite sheet to change and reduce its thermal conductivity. If the hot pressing temperature is too low or the pressure is too small, the density and bonding strength of the graphite sheet are not enough, which will also affect its thermal conductivity.
- Surface treatment process: The surface treatment of graphite sheets can improve its binding performance and heat dissipation effect with other materials. For example, coating a layer of metal or ceramic material on the surface of the graphite sheet can improve the thermal conductivity and wear resistance of the surface; The oxidation treatment of graphite sheet can increase its surface roughness and improve the binding force with glue and other adhesives.
3. Use environment:
- Temperature: The thermal conductivity of the graphite sheet will change with the change of temperature. At low temperature, the thermal conductivity of graphite sheet will decrease; At high temperatures, the structure of the graphite sheet may change, resulting in reduced thermal conductivity. Therefore, when using thermal graphite sheets, it is necessary to consider its operating temperature range and choose the appropriate thermal graphite sheets.
- Pressure: When the heat conductive graphite sheet is subjected to pressure, its internal structure will change, resulting in a change in thermal conductivity. In practical applications, if the contact pressure between the thermal graphite sheet and the heating element or radiator is uneven, the heat conduction efficiency will be affected and the heat dissipation effect will be reduced.
- Installation method: The installation method of thermal graphite sheet will also affect its heat dissipation effect. If the thermal graphite sheet is not firmly installed, or the contact area between the heating element and the radiator is not enough, the heat can not be effectively conducted out, affecting the heat dissipation effect.