Thermally conductive silicone is a thermally conductive medium used to reduce contact thermal resistance between the surface of a heat source and the contact surface of a heat sink. In the industry, it can also be called thermally conductive silicone sheet, thermally conductive silicone pad, soft heat sink, and so on. There are some differences in the manufacturing process of thermally conductive silicone pads by different manufacturers. Production process of liquid thermal silicone pad calender: 1. Raw material preparation The thermal conductivity of ordinary organic silica gel is poor, and the thermal conductivity is usually only about 0.2W / m · K. However, mixing thermal conductive filler in ordinary silica gel can improve its thermal conductivity. Commonly used thermally conductive fillers are metal oxides (such as Al2O3, MgO, BeO, etc.) and metal nitrides (such as SiN, AlN, BN, etc.). The thermal conductivity of the filler is not only related to the material itself, but also closely related to the particle size distribution, morphology, interface contact, and the degree of internal molecular bonding of the thermally conductive filler. In general, the thermal conductivity of a fibrous or foil-like thermally conductive filler is better. 2.Mixing and vacuuming Mixing is a process of silica gel processing, which refers to the use of mechanical or chemical methods to reduce the molecular weight and viscosity of raw rubber to improve its plasticity, and obtain appropriate fluidity to meet the needs of mixing and molding for further processing. The raw materials for making thermal silica gel pads are generally destroyed by high-speed mechanical stirring. After color matching and mixing, the milky silica gel displaces various colors of tablets. 3. Calendering The kneaded uniform slurry is injected into a rolling hopper through a vacuum pipe, and precision rolling coating is performed. 4.Vulcanization After calendering, high temperature vulcanization is performed. 5, trimming and cutting After the high temperature treatment, the thermally conductive silicone sheet needs to be left for a period of time to allow it to cool naturally before being cut in different sizes and specifications, and other rapid cooling methods cannot be used. Otherwise, it will directly affect the product performance of the thermal silica pad. 6.Finished product inspection
The main items to be tested in the finished product include: thermal conductivity, temperature range, volume resistivity, voltage resistance, flame retardancy, tensile strength, hardness, thickness, etc.