Heat dissipation can be simply divided into active heat dissipation, passive heat dissipation (conduction, convection and radiation). Thermal design engineers will choose the appropriate heat dissipation method and heat conduction material according to the heat condition. When selecting the heat transfer medium, it is not only necessary to consider its heat transfer capacity, but also to take into account the production process, convenience, maintainability and cost-effective factors. At present, the commonly used thermal interface materials are: thermal conductive silicone sheet, thermal conductive silicone grease, thermal insulating materials and so on. The following are simple descriptions of the characteristics of these types of thermal conductivity materials, and the indicators that need to be paid attention to when selecting them:
1. Thermal conductive silicone sheet
A heat-conducting interface material with high softness, high compliance and high compression ratio, which can fill the gap between the heating component and the radiator (shell) to improve heat transfer
Efficiency, but also can play a role in insulation, shock absorption and so on. In the selection, the thickness, thermal conductivity, working temperature range, pressure resistance and other parameters should be selected according to the actual situation. At the same time, it is also necessary to pay attention to the hardness, volume resistivity, dielectric constant, tensile strength and other parameters.
2. Thermal grease
Commonly known as thermal conductivity paste, heat sink paste, is a kind of silicone oil as a base oil, metal oxide as a filler, with a variety of functional additives, processed by a specific process of paste thermal interface material. It has high thermal conductivity, low thermal resistance, wide operating temperature range, low volatility, low oil separation, strong weather resistance and other excellent performance. The selection is mainly concerned with the following indicators: oil separation, thermal conductivity and thermal resistance, viscosity, temperature range, dielectric constant.
