Views: 3 Author: Site Editor Publish Time: 2019-03-24 Origin: Site
Continuous upgrading of heat dissipation technology schemes, the market scale in 5G era is expected to exceed 200 billion yuan
Thermal design and thermal management are the core components of electronic products. There are many downstream applications of heat dissipation, including consumer electronics, automobiles, base stations, servers and data centers. The market space is at the level of 100 billion. According to the prediction of prospective industry research institute, the annual compound growth rate of heat dissipation industry is 8% from 2018 to 2023, and the market scale is expected to grow from 1497 billion yuan in 2018 to 219.9 billion yuan in 2023. Smartphone heat dissipation accounts for about 7% of the total scale of the industry, and from the long-term development trend, 5G brings the increase of network traffic, and the server heat dissipation market will continue to expand.
Passive heat dissipation is the main method and multi-material is the current solution of heat dissipation design
The principle of heat dissipation includes three kinds: Heat Conduction, Heat Convection and Heat Radiation. Generally speaking, heat conduction and heat convection are the two main ways of heat dissipation system, in which heat conduction is mainly related to the thermal conductivity and heat capacity of radiator materials, while heat convection is mainly related to the radiation area of radiator.
According to different means of heat conduction and convection, radiator products can be divided into active and passive ways. Desktop computers and notebook computers use active and passive heat dissipation, while light and thin consumer electronics such as mobile terminals and tablets are mostly passive heat dissipation schemes because of the limitation of internal space structure.
Heat dissipation
| Heat dissipation | heat conduction | heat convection | heat radiation |
| Heat Dissipation Principle | Contact between Heat Dissipator and Heat Source Chip | Heat Dissipation Fan Drives Air Flow and Heat Transfer | Radiation of Heat Dissipating Material |
| Influencing factors | Thermal conductivity and heat capacity of materials | Heat Exchange Area and Air Flow Velocity of Radiator | Blackness of materials |
At present, the mainstream passive heat dissipation schemes include graphite sheet, graphene, metal backplane, ice nest heat dissipation, Thermal Interface Materials (TIM), Heatpipe (HP) and Vapor Chamber (VC). The thermal conductivity is the core index to measure the heat dissipation scheme. The thermal conductivity of the above schemes ranges from low to high, in order of metal, graphite sheet, graphene, heat pipe and VC.
Although the thermal conductivity of heat pipe and VC is higher, its function is only to speed up the transfer of heat from the smart phone heating parts to the radiator, and the final heat dissipation effect depends on the heat convection between the radiator and the air, that is, the thermal characteristics of the radiator material have a significant impact on the radiation effect of the smart phone. Therefore, the solution of graphite sheet + heat pipe / VC integration is expected to become the mainstream of development, which will benefit the participants in graphite sheet, TIM and heat pipe / VC industry chain.
Graphite film: Mainstream Material for Heat Dissipation Scheme, Domestic Technology is Mature and Stable
Graphite has good horizontal and vertical thermal conductivity. At the same time, the specific heat capacity of graphite is equal to that of aluminium, about twice that of copper, which means that graphite temperature increases by only half of that of copper after absorbing the same heat. In addition, the density of graphite is only 0.7-2.1g/cm3, which is lower than 8.96g/cm3 of copper and 2.7g/cm3 of aluminium. Therefore, the graphite can be lightweight and can adhere smoothly to any plane and curved surface.
Based on the advantages of high thermal conductivity, high specific heat capacity and low density, graphite has been widely used in consumer electronics since 2009, and in smartphones since 2011. It has replaced traditional metals and become the mainstream heat dissipation material in the field of consumer electronics.
Matching thermal conductive filling materials, application scenarios are numerous and indispensable
Thermal Interface Materials (TIM) is a common heat dissipation method, which is widely used in IC packaging and electronic heat dissipation.
There are many kinds of thermal conductive interface materials, including thermal conductive silicone grease, thermal conductive silicone film, thermal conductive phase change material and thermal conductive double-sided adhesive. Thermal conductive silicone grease has good fluidity. It can be used in heating devices by dispensing, printing and other ways. It is suitable for thermal conductive functional composites with smaller clearance or zero clearance. Thermal conductive silicone grease has ultra-low thermal resistance, so it is suitable for high calorific close-fitting scenarios. It has the lowest thickness of thermal conductive products and can quickly transfer heat out of equipment to achieve good temperature control. In addition, thermal conductive silicone films, phase change materials and double-sided adhesives are also widely used in different scenarios and needs.
