| 摘要 |
A layered abradable thermal barrier coating (TBC) 20 that is stable, abradabie, and sinter resistant up to about 1400° C. A tungsten bronze structured ceramic of the form Ba6-3xRE8+2xTi18O54, where 0<x<1.5, and RE represents a rare earth lanthanide cation, is applied as a topcoat over a yttria stabilized zirconia (YSZ) undercoat (18) on a bond-coated (17) superalloy metal structure (16). The tungsten bronze structure provides abradability and thermal conductivity. The YSZ layer is a proven concept for thermal barrier coatings, and has demonstrated better adhesion than newer chemistries This combination of layers has synergy that takes advantage of both materials to provide an abradable coating with an extended lifespan on a superalloy substrate compared to prior coatings. The topcoat may be applied with fugitive inclusions that produce porosity to increase abradabilty for improved blade tip clearance control in the turbine section of gas turbines. |
