With the development of the industry, mobile phones will be more intelligent, higher configuration, faster computing speed and higher CPU frequency. For multi-functional and multi task smart phones, such as running large-scale software or games for a long time, the temperature of CPU, LCM and other devices will be higher, and the performance will be sharply reduced. Like all electronic devices, only within the appropriate temperature range can the devices work normally and persistently. Therefore, heat dissipation is to ensure that these devices are not burned; on the other hand, they can work well. At the same time, WiFi and other communication devices will generate a lot of heat along with the transmission and reception of effective signals because they need to transmit and receive signals. When the temperature is too high, the mobile phone will start the self-protection mechanism and automatically power off, which will also affect the normal use of the mobile phone.
Heat conduction graphite sheet
Graphite cooling film, in fact, is a "heat conducting graphite sheet", also known as graphite cooling sheet. It is a kind of nano advanced composite material, which can adapt to uniform heat conduction on any surface and has EMI electromagnetic shielding effect.
The chemical composition of the graphite heat sink is mainly a single carbon (c) element, which is a natural element mineral. The graphitized film can be obtained by chemical method under high temperature and pressure, because the carbon element is a non-metallic element, but it has the conductivity and thermal conductivity of the metal material, as well as the plasticity like the organic plastic, as well as the special thermal performance and chemical stability, Lubrication and coating on the solid surface and other good process properties, graphite fins in the plane with 150-1500 w / m-k range of ultra-high thermal conductivity.
Main characteristics of graphite heat sink: super high thermal conductivity / easy to operate, low thermal resistance, light weight. It has been widely used in communication industry, medical equipment, Sony / Dell / Samsung notebook, mobile phone, PC memory module, led substrate and other aspects of heat dissipation.
Using the plasticity of graphite, we can make a piece of graphite material like a sticker, which can be attached to the circuit board inside the mobile phone. To be exact, graphite heat sink actually plays a role of heat conduction and evenly distributing heat on the surface, indirectly, it also plays a role of heat dissipation.
The characteristics of graphite sheet
(1) The surface can be combined with metal, plastic, adhesive and other materials to meet more design functions and needs.
(2) Low thermal resistance: the thermal resistance is 40% lower than that of aluminum and 20% lower than that of copper.
(3) Light weight: 25% lighter than aluminum and 75% lighter than copper.
(4) High thermal conductivity: graphite sheet can be smoothly attached to any plane and curved surface, and can be cut in any form according to the needs of customers.
Thermal conductivity ratio
Thermal conductivity w / MK conductivity Simens / M density g / cm3
Aluminum 2003 × 1072.7
Copper 3806 × 1078.96
Graphite 150-1500 horizontal - 2 × 1050.7-2.1
5-60 vertical 100
Heat dissipation principle of graphite heat conducting film
Physical photos of graphite sheet
Samples of graphite sheets
Analysis cases of mobile phone heat dissipation of various brands of smart phones
