High purity zirconia-based thermally sprayed coatings and processes for the preparation thereof

US9085490B2 · kind B2 · utility

Assignee

• Praxair S.T. Technology, Inc. · US

Inventors

• Thomas Alan Taylor · Beloit, US
• Danny Lee Appleby · Indianapolis, US
• Albert Feuerstein · Neuberg, DE
• Ann Bolcavage · Indianapolis, US
• Neil Hitchman · Carmel, US

Key dates

• Filing date: Oct 22, 2012
• Grant date: Jul 21, 2015
• Expiry date: Oct 22, 2032

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/2991
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

This invention relates to thermally sprayed coatings of a high purity yttria or ytterbia stabilized zirconia powder, said high purity yttria or ytterbia stabilized zirconia powder 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 component such as blades, vanes and seal surfaces of gas turbine engines, made from the high purity yttria or ytterbia stabilized zirconia powders, have a density greater than 88% of the theoretical density with a plurality of vertical macrocracks homogeneously dispersed throughout the coating to improve its thermal fatigue resistance.