Thermal Gap Pad and Thermal Insulation
Thermal insulation is generally made of polyurethane foam or fiberglass. Fiberglass insulation is sold in batts, blankets or rolls that are typically rolled between studs and joists for use in unfinished floors, ceilings and walls. Polyurethane can be applied as a liquid, gel or spray. It is often used to fill in gaps between circuit boards, the board and heat sink or to fill small holes and spaces. Foams are also useful for reducing vibration and shock that can damage electronics.
What is Thermal Gap Pad, on the other hand, are soft and conformable. They can fill in any surface voids, or unevenness, between the mating surfaces. This helps ensure the entire surface area makes contact, maximizing heat transfer from the heat sink. These grips are more comfortable, provide a better grip, and help to absorb vibrations and shocks. This can improve component longevity and reliability.
Thermal gap pads come in many different densities, conductivities and hardnesses. The difference in these qualities can have a significant impact on the price and quality of the product. Some of the variations are due to the manufacturing method, with different recipes being used by manufacturers. This results in a wide range products. However, the formula and how the gap-filler is used are responsible for a large portion of the variations in performance.
Bergquist offers GAPPAD, a line consisting of gels and liquids designed to meet electronic industry demands for thermal management products that offer greater conformability as well as higher temperature performance. These nonadhesive liquid thermal gap-fillers are dispensed straight onto surfaces. They remain pliable and flexible during assembly for easy application. The materials have a high modulus, which allows them to flex without losing their thermal performance. They also feature natural tack both on the front and back so that they don’t need additional adhesives.
Gap-fillers can be applied in a number of ways. From squeezing between the board surface and heat sink, to filling small spaces with a fingertip, or brush. Some are offered with a pressure sensitive adhesive to make application even easier. They are also available in a variety of shapes and sizes to fit the unique contours of electronic components. The liquids are not only used to fill gaps and insulate, but they can also act as a cooling agent. This is particularly useful when space is limited or the heat sink cannot be accessed. They can be pressed onto the heat sink or the bottom board. This step is crucial for maintaining a strong thermal connection between CPU and heatsink, especially as the size of microprocessors continues to shrink.