Venkat Nandivada, Manager of Technical Support at Master Bond Inc, talks to AZoM about their new adhesives with low thermal resistance and the role they play in the electronics industry.
Why is there a need for new thermal resistance adhesives?
As the electronic industry continues to yield faster, high-density devices, materials capable of coping with increasing heat loads are essential. The ability of thermally conductive adhesives to help dissipate heat has motivated their use as the preferred fastening approach in applications requiring careful thermal management. Moreover, adhesives with very low thermal resistance characteristics aid in extending electronic device performance, service life, reliability and integrity.
What new products has Master Bond developed to address the needs of the industry?
Supreme 18TC is a one component epoxy with very low thermal resistance and high thermal conductivity that is also NASA low outgassing approved. Supreme 18TC can be applied in bond lines as thin as 10-15 microns, which leads to lower thermal resistance and higher thermal conductivity. It offers an exceptionally low thermal resistance of 5-7 x 10-6 K•m2/W and a thermal conductivity of 22-25 BTU•in/ft2•hr•°F [3.17-3.61 W/(m•K)].
The bottom line: Supreme 18TC has very low thermal resistance, since it is highly thermally conductive and able to cure effectively in thin layers. Another way of looking at this is to say that the lower the thermal resistance, the better the heat transfer.
Another new product is EP48TC. This two component adhesive features the same heat transfer capabilities as Supreme 18TC, as well as the ability to be cured in thin bond lines. It has an optimum cure schedule of overnight at room temperature, followed by 3-5 hours at 150-200°F. EP48TC also features minimal shrinkage upon curing, a low coefficient of thermal expansion and a Shore D hardness of 85-95. Both products have excellent electrical insulation properties over a wide service temperature range.
Why is a thin bond line desirable?
The thickness of the bond and nature of the surfaces meeting at the bond interface can work to impede heat transfer. Consequently, manufacturers look to join materials with the thinnest- possible bond lines. In fact, a thin bond line is preferred over a thick one, since it not only helps in reducing the thermal resistance, but also imparts lesser stress at the corners of the bond joint. Minimum thickness also means fewer chances of air voids that can lead to eventual bond failure.
What are some of the challenges adhesive manufacturers face when developing new products?
Adhesive suppliers typically specify a material’s thermal properties in terms of bulk thermal conductivity, which describes the material’s ability to transfer heat through itself. In electronic design, however, thermal management remains focused less on material specifics than the broader issue of dissipating or transferring heat from a die through a package or from a component through a heat sink.
The bulk thermal conductivity specification addresses only part of the objective of internal heat transfer. In a typical product assembly, a more practical characteristic is the material’s thermal resistance. Thermal resistance describes the ease with which heat can transfer across the interface between the die (or component) surface and bonding material, across the bonding material, and finally across the interface between the bonding material and package (or heat sink).
In what industries is there a demand for thermal conductive adhesives?
Besides their use in areas such as power electronics and solar energy, thermally conductive adhesives play a vital role in the rapid growth of the LED lighting industry. Since light output falls as temperatures rise, the thermal conductive properties of adhesives are particularly important in this arena. By using these adhesives, LED providers are able to deliver highly efficient LED lighting products. Furthermore, because these adhesives remain resistant to typical environmental stresses such as weathering and corrosion, these products can help deliver the extended operating life expected in the marketplace.
Both systems mentioned above, Supreme 18TC and EP48TC, can be used in a variety of industries, including aerospace, electronic, optical, cryogenic, OEM, and many other high technology industries where optimum thermal transfer properties are a necessity.
Where can our readers find out more?
For more information on Supreme 18TC, watch this video http://www.masterbond.com/video/product-spotlight-supreme-18tc. You may also read more about this product at http://www.masterbond.com/tds/supreme-18tc. For more information on EP48TC, please go to http://www.masterbond.com/tds/ep48tc.
If you have an application you'd like to discuss please contact us at [email protected] or http://www.masterbond.com/contact.
About Venkat Nandivada
Venkat Nandivada has been the Manager of Technical Support at Master Bond Inc since 2010. He has a Masters in Chemical Engineering from Carnegie Mellon University.
He analyzes application oriented issues and provides product solutions for companies in the aerospace, electronics, medical, optical, OEM and oil/chemical industries.
Disclaimer: The views expressed here are those of the interviewee and do not necessarily represent the views of AZoM.com Limited (T/A) AZoNetwork, the owner and operator of this website. This disclaimer forms part of the Terms and Conditions of use of this website.