Yttria-stabilized zirconia with reduced thermal conductivity

摘要

A thermal barrier coating (TBC) for a component intended for use in a hostile environment, such as the superalloy turbine, combustor and augmentor components of a gas turbine engine. The TBC is formed of zirconia that is partially stabilized with yttria (YSZ), preferably not more than 3 weight percent yttria, and to which one or more additional metal oxides are alloyed to increase crystallographic defects and lattice strains in the TBC grains and/or form precipitates of zirconia and/or compound(s) of zirconia and/or yttria and the additional metal oxide(s), the inclusion of which reduces the thermal conductivity of the YSZ to levels lower than conventional 6-8% YSZ. Improvements are particularly contemplated for TBC having a columnar grain structure, such as those deposited by EBPVD and other PVD techniques.