SBIR Phase I: Chemically Bonded Ceramic Exhaust Coating

This Small Business Innovation Research (SBIR) Phase I project will center on the development of a new chemically-bonded amorphous ceramic network (CBACN) for use as a thermal coating in next-generation engine exhaust thermal management systems. The coating will permit a combination of performance, price and processing parameters superior to currently available technologies. The potential outcome of the proposed work will be a low-cost, easy to apply, thermal barrier coating that bonds to exhaust components, reducing the net heat loss from the exhaust to the surrounding components. Thermal exhaust coatings offer improved engine and catalytic efficiency, lower under-hood temperature, and reduce vehicle weight. The net effect for the consumer is improved efficiency, reduced greenhouse gas emissions, reduced pollution, improved safety, and lower cost. The net outcome for automobile manufacturers will be higher corporate average fuel economy (CAFE) scores, a simplified manufacturing process, and an estimated cost savings of $20 per vehicle. Current ceramic exhaust coatings are too costly for use by original equipment manufacturers (OEMs). The potential outcome of the proposed research is a ceramic exhaust coating for use in a thermal management system appropriate for OEM use. The intellectual merit of this project derives from the advancement of low-cost, easy to apply, chemically-bonded ceramics into a market currently occupied by difficult-to-apply plasma sprayed ceramic coatings. Target features for these coatings include thermal conductivity less than 5 W/m-K, emissivity below 0.3, adhesion to exhaust-grade stainless steel, thermal stability, wear resistance, chemical resistance, and ease of coating and integration into the vehicle manufacture supply chain. CBACNs may be formulated with a wide range of physical properties not obtainable in a sintered ceramic system. Related CBACN coatings have been developed with enough adhesion and flexibility on 400 series exhaust stainless steel to survive a 35 degree bend around a 10 mm mandrel. Independently, CBACN coatings have been developed with emissivity below 0.2 and with thermal conductivity below 1 W/m-K, although no single coating has been developed with all the desired properties simultaneously. This project will focus on the material synthesis and evaluation tasks needed to realize such a material system.