Heat-resistant fluorosilicone extends design options for automotive applications

Addressing material requirements for demanding automotive applications that require long-lasting, reliable performance at temperatures exceeding 220°C, Dow Corning has debuted a series of fluorosilicone rubber (FSRs).

"With automotive design trending toward smaller engine compartments, increased exhaust gas recirculation and decreased air flow, the high-end temperatures in underhood environments are climbing and, more importantly, driving the performance requirements for FSRs to extremes not previously required," said Craig Gross, senior application engineer for Fluorosilicone Elastomers at Dow Corning. "In collaboration with the automotive industry, Dow Corning has developed an innovative new technology platform for its Silastic FSR line that boosts temperature resistance for extended periods of time and offers expanded flexibility for next-generation automotive designs."

FSRs fall into a special class of silicone polymers that add enhanced chemical resistance to the excellent temperature performance typical of silicone technology. These materials withstand long exposure to aggressive automotive fluids, fuels and oils, and conventional grades perform reliably at temperatures reaching 200°C, making them a common material solution for turbocharger hoses, fuel systems and transmission seals. Even with the help of performance-enhancing additives, however, traditional FSR grades are reaching their limits as new automotive designs steadily drive underhood temperatures ever higher.

Dow Corning's FSR expertise FSRs, however, allowed the company to take a holistic approach to this industry challenge by looking at polymer design, raw materials, additives and processing in order to boost overall material performance. As a result, the company was able to develop a new FSR technology platform that delivers reliable, long-lasting performance at higher temperatures. The company validated these performance improvements by subjecting its enhanced FSR technology to long-term heat aging, fluid exposure and elevated mechanical testing and adhesion to high-consistency rubber (HCR). These tests confirmed that Dow Corning's advanced FSR technology delivered reliable performance at temperatures above 220°C for extended periods of time.

By leveraging this advanced technology, Dow Corning can now tailor new cutting-edge FSR solutions that target the precise performance needs of customer applications, including easier processing, thinner wall sections, lower weight, reduced systems cost and more stable performance over a broader temperature range compared to conventional solutions.

The compounds are available globally, and come as ready-to-use rubber crepe mixtures designed for traditional molding, calendering and extrusion processes.