a recent article on engineering.com outlined new choices that are available to engineers looking for solutions to increasing component density and high-power requirements. the article explored the increasing use of thermally conductive adhesives, sealants, and potting compounds that save space while dissipating heat.

thermally conductive adhesives are being used to add components to a pcb.
(wikimedia commons)

“one- and two-component epoxies, silicones, solvent-based compounds and epoxy films can be used for thermal, environmental and structural stability requirements,” wrote kagan pttman. “these materials can optimize heat transfer across interfaces for electronic devices in industries from medical to aerospace.”

as pittman noted, thermally conductive adhesives also provide stability against shock and vibrations, but there are considerations that need to be understood in order to make the right choice for what type of adhesive to use.

“modern adhesive chemistries can combine the best properties of different materials to find ideal solutions for any application,” pittman continued. “thermally conductive adhesives, sealants and compounds can be designed for flexibility or rigidity, as well as with customizable viscosity and cure rates.”

one of the issues that comes up often is finding the correct ratio between conductive filler and bond strength because added filler means less epoxy for the adhesion. solutions are available for this that have a range of properties from moisture resistance to the ability to withstand high and low temperatures.

pittman wrote, “the proper application of the adhesive is just as sensitive as its creation. adhesive compounds need to be applied carefully, yet fully, to prevent the forming of voids while also minimizing curing times.”

the article recommends automaton for the assembly process to ensure the right fit every time.

read the full article on thermally conductive adhesives at http://www.engineering.com/advancedmanufacturing/articleid/15170/advanced-thermally-conductive-adhesives-for-high-power-electronics.aspx.