Damping Properties of Hard Coatings for Engine Applications
Although blade coating materials dissipate vibratory energy while acting as thermal barrier coatings or protecting the substrate against corrosion or erosion, the inherent nonlinearity of these materials complicates the determination of the necessary material parameters. While plasma-sprayed ceramics alone do not appear to provide the desired levels of dissipation, notable increases in damping have been found to result from the inclusion of small amounts of viscoelastic materials. With proper selection of the added component, the resulting coating may be tailored for high damping in a specific temperature range. Vacuum infiltration of polymeric components into plasma-sprayed ceramics raise the dissipation to desired levels for temperatures of 93-135 oC; co-spraying mixtures of ceramics and glass frits leads to extremely high damping in the transition range of the glass, typically 550-800 oC.
Pietro VINCENZINI and Ghislain MONTAVON
P. J. Torvik "Damping Properties of Hard Coatings for Engine Applications", Advances in Science and Technology, Vol. 66, pp. 126-135, 2010