Wetting, infiltration and interaction behavior of CMAS towards columnar YSZ coatings deposited by plasma spray physical vapor

Zhang, Baopeng; Song, Wenjia and Guo, Hongbo (2018): Wetting, infiltration and interaction behavior of CMAS towards columnar YSZ coatings deposited by plasma spray physical vapor. In: Journal of the European Ceramic Society, Vol. 38, No. 10: pp. 3564-3572

Abstract

Thermal barrier coatings (TBCs) produced by electron beam physical vapor deposition (EB-PVD) or plasma spray (PS) usually suffer from molten calcium-magnesium-alumino-silicate (CMAS) attack. In this study, columnar structured YSZ coatings were fabricated by plasma spray physical vapor deposition (PS-PVD). The coatings were CMAS-infiltrated at 1250 degrees C for short terms (1, 5, 30 min). The wetting and spreading dynamics of CMAS melt on the coating surface was in-situ investigated using a heating microscope. The results indicate that the spreading evolution of CMAS melt can be described in terms of two stages with varied time intervals and spreading velocities. Besides, the PS-PVD columnar coating (similar to 100 mu m thick) was fully penetrated by CMAS melt within 1 min. After the CMAS attack for 30 min, the original feathered-YSZ grams (tetragonal phase) in both PS-PVD and EB-PVD coatings were replaced by globular shaped monoclinic ZrO2 grains in the interaction regions.

• Item Type: Journal article
• Faculties: Geosciences > Department of Earth and Environmental Sciences
• Subjects: 500 Science > 550 Earth sciences and geology
• ISSN: 0955-2219
• Language: English