Thermal compounds are used for the heat dissipation in electronic and related equipment to ensure an effective function.
Most components have a maximum effective operating temperature. Exceeding that temperature can lead to two main problems:
-Increased failure rates
-Change of the electrical properties
The generated heat in the components is normally dissipated by the use of metals that may be shaped to create large surface areas (heat sinks). Usually the hot component is mechanically attached to the metal. The problem is that there will always be an air space between the surfaces.
As air is a bad heat conductor, this air space will considerably reduce the heat dissipation rate. Attaching a flexible and thermally conductive material fills the space completely and excludes the air. These products have excellent heat transfer properties, whereas the heat flows from the component into the metal body as fast as possible.
The range includes:
Heat transfer compounds
The most common pastes are silicone-based and have excellent stability at high temperatures.
The silicone-free pastes offer all advantages of silicone-based materials, eliminate, however, the risk of contamination by migrating free silicones causing the failure of a switch or a bad adhesion of coatings and protective films.
Epoxy resins
These two-part thermally conductive resin systems offer manufacturers a permanent mechanical adhesion between the component and the heat sink. That is why no mechanical fastening parts are needed. As PCBs are getting more complex and more powerful, the problem of heat generation must be treated in a careful way to ensure an optimum effectiveness and an increased life expectancy of the components. The use of these thermally conductive products offer an extremely cost-effective and efficient solution of the problem.