Hot corrosion behavior and wettability of calcium–magnesium–alumina–silicate (CMAS) on LaTi2Al9O19 ceramic. (January 2020)

• Record Type: Journal Article
• Authors: Qu, Weiwei; Li, Shusuo; Chen, Zehao; Li, Chun; Pei, Yanling; Gong, Shengkai
• Is Part Of: Corrosion science. Volume 162(2020)
• Publication Date: 2020-01
• Subjects: LaTi2Al9O19 ceramic -- Thermodynamic calculation -- Wettability -- Calcium-magnesium-alumina-silicate (CMAS) -- Anorthite; Corrosion and anti-corrosives -- Periodicals; 620.11223
• DOI: 10.1016/j.corsci.2019.108199
• Languages: English
• ISSNs: 0010-938X

Abstract

Highlights: Abstract LTA plays a significant role in preventing Ca and Si in CMAS infiltration. The continuous CaAl2 Si2 O6 layer is generated at the interface of CMAS and LTA. Effects of Ti and Al on CMAS are revealed from thermodynamic perspective. Compared with YSZ, LTA shows better wettability against CMAS. Abstract: The development of thermal barrier coating (TBC) has been limited by the calcium–magnesium–alumina–silicate (CMAS) corrosion. In this work, a promising CMAS-resisted LaTi2 Al9 O19 (LTA) rich in Ti and Al is proposed. CMAS corrosion behavior of LTA ceramics is investigated at a temperature range of 1200 °C- 1300 °C. By combining the experimental results and thermodynamics analysis, Ca and Si are arrested effectively by formation of CaAl2 Si2 O8 layer and (Ca, La0.7 )(Ti, Al)O3 to prevent CMAS from moving downward. Meanwhile, the contact angle of CMAS on LTA is larger than that of YSZ, contributing to the CMAS resistance.