Thermo-Mechanical Behavior of Nanostructured Plasma Sprayed Zirconia Coatings

Retaining non-melted nano-particles of zirconia in nanostructured coatings has been a challenge in the past. Recently an air plasma spray process was developed to produce coatings which retain up to 30-35% by volume non-melted particles, resulting in a unique structure. The creep/sintering behavior of such thermal barrier coatings deposited from nanostructured feedstock has been measured and compared with deposits produced from hollow sphere powder (HOSPTM). Both feedstocks contain 6-8wt% Y₂O₃ as stabilizer. Flexure and compression creep testing were conducted under several different loads and temperatures to obtain creep exponents and parameters.