An Improved Deposition Process for Very Thick Porous Thermal Barrier Coatings

This paper discusses the development of a two-layer thermal barrier coating that reduces heat flow to the lowest allowable level based on the temperature limits of the materials involved. The thick, porous coating was sprayed using a modified plasma torch and then thermally cycled until failure. Test results show that the process used to apply the bond coat has a measurable effect on the performance of the thermal barrier coatings. In addition to zirconia powders, a low cost polymer powder was used as well. Paper includes a German-language abstract.