Thermal protection of components in crowded underhood environments can present particular difficulties for design engineers. To help ease the situation, thermal-management specialist Zircotec has developed what it believes is the first flexible ceramic heat-shield material.
Called ZircoFlex (patent pending), it is described by the company as offering a low-cost thermal protection solution and is easily applied to the material surface. The product will be supplied in a roll for heat protection in a wide range of automotive applications.
"ZircoFlex has the potential to transform the use of ceramic heat protection," said Zircotec Sales Director Peter Whyman. "For the first time, these coatings can be installed inline to parts and assemblies during manufacture—even in high-volume applications—without disrupting production flow."
He said that the company was continuing its research into flexible ceramic coatings and planned to produce an expanded range of ZircoFlex foils using a range of alternative substrates.
Zircotec’s plasma-sprayed ThermoHold-based coatings are currently used for the protection of metallic and composite components in a range of applications. Applied to the material surface in a lightweight layer, they can reduce surface temperatures by up to 33%, according to the company. But a limitation of the process has previously been the need to treat parts directly using 14,000ºK plasma sprays.
Now, the new ZircoFlex technology allows its coatings to be supplied as a thin aluminum-backed foil. The material is lightweight (460 g/m2) and measures 0.25-mm (0.01-in) thick but is described as being robust and easy to handle. It can be cut and installed by hand or machine and has been designed to be easily fixed in place using mechanical fasteners or high-temperature adhesives. This facilitates integration directly into conventional production or maintenance operations.
Ceramic coatings are naturally brittle, which has limited their use up until now to rigid substrates, explained Whyman: "The new ZircoFlex product, which is the culmination of more than five years’ intensive research and materials science, uses a new technology in which the ceramic material is sprayed in the form of thousands of individual 'platelets' onto the surface of the foil."
They are close-packed to provide comprehensive heat protection, but the structure allows the foil to be bent and manipulated to suit required geometries. It can also be folded tightly through 180º without damaging the thermal barrier.