A reduced
thermal conductivity thermal barrier coating having improved
impact resistance for an underlying substrate of articles that operate at, or are exposed to, high temperatures. This
coating comprises an inner
high fracture toughness layer nearest to the underlying substrate and having a thickness up to about 5 mils (127 microns) sufficient to impart
impact resistance to the
thermal barrier coating, and comprises a zirconia-containing
ceramic composition having a c / a ratio of the zirconia lattice in the range of from about 1.011 to about 1.016 and stabilized in the tetragonal phase by a stabilizing amount of a stabilizing
metal oxide selected from the group consisting of yttria, calcia, ceria, scandia, magnesia, india, lanthana, gadolinia, neodymia, samaria, dysprosia, erbia, ytterbia, europia, praseodymia, and mixtures thereof. The
thermal barrier coating further includes an outer thermal insulating layer adjacent to and overlaying the inner layer and comprising a
ceramic thermal barrier
coating material. The thermal barrier can be used to provide a thermally protected article having a substrate (e.g.,
metal substrate) and optionally a
bond coat layer adjacent to and overlaying the substrate. The thermal barrier
coating can be prepared by forming the inner
high fracture toughness layer, followed by forming on the inner layer the outer thermal insulating layer.