Coated articles

摘要

This invention relates to high purity yttria or ytterbia stabilized zirconia powders comprising from about 0 to about 0.15 weight percent impurity oxides, from about 0 to about 2 weight percent hafnium oxide (hafnia), from about 6 to about 25 weight percent yttrium oxide (yttria) or from about 10 to about 36 weight percent ytterbium oxide (ytterbia), and the balance zirconium oxide (zirconia). Thermal barrier coatings for protecting a substrate such as blades, vanes and seal surfaces of gas turbine engines made from the high purity yttria or ytterbia stabilized zirconia powders have a plurality of vertical macrocracks homogeneously dispersed throughout the coating to improve its thermal fatigue resistance. The invention also relates to processes for producing the thermal barrier coatings.