Heat dissipation materials: understand the thermal conductive graphite heat sink
With the development trend of consumer electronics toward ultra-thin, intelligent and multifunctional, the increasing power and thinner products have increasingly revealed the problem of how heat is dissipated. Because of its outstanding properties in thermal conductivity, thermally conductive graphite sheets have received more and more attention and have been widely used in smart phones, ultra-thin PCs and LED TVs.
Due to its unique crystal grain orientation, the thermally conductive graphite sheet conducts heat uniformly in two directions (X-Y axis and Z-axis). The layered structure can be well adapted to the surface fluctuations of the device after processing. The unique crystal structure and processing method enable It can provide thermal isolation and shielding of heat sources and components while conducting uniform heat conduction, which significantly improves the performance of electronic products.
What is thermal graphite sheet?
Thermally conductive graphite sheet is a brand-new thermal and heat dissipation material that conducts heat uniformly in two directions, shielding the heat source and components, and improving the performance of consumer electronic products. With the upgrading of electronic products, accelerated, mini, highly integrated, and high-performance electronic devices are increasingly demanding heat dissipation management.
This new natural graphite solution has high heat dissipation efficiency, small footprint and light weight. The color is generally black, and the material is natural graphite after exquisite processing, and the thermal conductivity is as high as 1500W/M-K in the horizontal direction. Commonly used in IC, CPU, MOS, LED, heat sink, LCD-TV, notebook computers, communication equipment, wireless switches, DVDs, handheld devices, etc.
Classification of thermal conductive graphite sheet:
Graphite flakes are divided into natural graphite flakes and artificial graphite flakes!
Natural graphite heat dissipation film has high thermal conductivity, easy construction, flexibility, no gas and liquid permeability, graphite chips are not aging and embrittlement, suitable for most chemical media, and the general thermal conductivity is 700~1200W/m.k. The disadvantage of natural graphite sheet is that it cannot be too thin. Generally, the thinnest finished product is 0.1mm thick. Therefore, the market share of natural graphite is getting lower and lower. At the same time, due to the structural factors of natural graphite itself, the heat dissipation effect of natural graphite Relatively weak.
Artificial graphite can be made very thin, and the heat dissipation effect is very good. The thermal conductivity is 1000~1500W/m.k, which is mainly reflected in the fast heat dissipation speed, but the price of artificial graphite is relatively high. As the mobile phone market is increasingly pursuing quality, synthetic graphite sheets are also popular.
Principle of Graphite Sheet Heat Dissipation:
A typical thermal management system is composed of an external cooling device, a radiator and a thermal section. Take smart phone products as an example:
1. Heat is quickly transferred to the casing and frame through the plane of the thermally conductive graphite sheet;
2. The surface of the thermally conductive graphite sheet enhances the infrared radiation effect;
3. The thermal conductive graphite sheet expands the plane heat dissipation area and quickly dissipates the heat dissipation point.
Processing and formation of thermal conductive graphite sheet: In order to better adapt to the undulating surface of electronic devices and circuit modules, it is necessary to perform certain processing on the thermally conductive graphite sheet. The main processing methods are:
1. Adhesive: For the purpose of better adhesion to IC and circuit boards, the adhesive is processed on the surface of the thermal conductive graphite sheet;
2. Back film: In some circuit designs that require insulation or heat insulation, in order to better optimize the function, the back film is processed on the surface of the graphite sheet.
We can select suitable processing methods according to the actual needs of the products .
