Thermal barrier coatings with improved impact and erosion resistance

摘要

A reduced thermal conductivity thermal barrier coating (22) having improved impact and erosion resistance for an underlying metal substrate (14) of articles (10) that operate at, or are exposed to, high temperatures. This coating (22) comprises a zirconia-containing ceramic composition having a c/a ratio in the range of from 1.0117 to 1.0148 and stabilized in the tetragonal phase by a stabilizing amount of a stabilizer metal oxide. The coating has a fraction of porosity of from 0.10 to 0.25, and an impact and erosion resistance property defined by at least one of the following formulas: (a) I = exp. Ä5.85 - (144 x s) - (3.68 x p)Ü; and/or; (b) E = Ä187 - (261 x p) - (9989 x s)Ü, wherein s = 1.0117 - c/a ratio; p is the fraction of porosity; I is least 140 g/mil; and E is least 130 g/mil. This coating (22) can be used to provide a thermally protected article (10) having a metal substrate (14) and optionally a bond coat layer (18) adjacent to and overlaying the metal substrate (14). The thermal barrier coating (22) can be prepared by depositing the zirconia-containing ceramic composition on the bond coat layer (18), or the metal substrate (14) in the absence of the bond coat layer (18).