High-temperature CMAS resistance performance of Ti2AlC oxide scales

• Published in: Corrosion science Vol. 174; p. 108832
• Main Authors: Jing, Jing, Li, Jimeng, He, Zhe, He, Jian, Guo, Hongbo
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Ltd 01.09.2020; Elsevier BV
• Subjects: Aluminum titanates; Calcium magnesium silicates; Calcium-magnesium-aluminium-silicate (CMAS); Contact angle; Diffusion layers; Diffusion rate; High temperature; Oxidation; Oxidation resistance; Scale (corrosion); Sessile drop method; Thermal barrier coatings; Thermal barrier coatings (TBCs); Ti2AlC; Wettability; Wetting; Oxidation; Thermal barrier coatings (TBCs); Wetting; Calcium-magnesium-aluminium-silicate (CMAS); Ti2AlC
• ISSN: 0010-938X; 1879-0496
• DOI: 10.1016/j.corsci.2020.108832

•Bi-layered oxide scales were developed by pre-oxidizing Ti2AlC bulk at different temperatures.•Molten CMAS corrosion behavior on scales at 1523 K was studied though a sessile-drop method.•CaTiO3 phase could help increase CMAS droplet viscosity and reduce spreading rate.•Glassy CMAS on Al2TiO5 layer shows the slowest spreading rate and the largest equilibrium contact angle among all. Failure of thermal barrier coatings (TBCs) caused by glassy deposits mostly composed of calcium-magnesium-aluminium-silicate (CMAS) has become an urgent issue. The addition of Al and Ti elements in TBCs is beneficial to improve the CMAS resistance. In this paper, bi-layered oxide scales were formed through pre-oxidation of Ti2AlC (POTAC) bulks at high temperatures. The wettability and spreading behaviors of CMAS on the oxide scales, as well as the interaction between them were investigated by a sessile-drop method. The glassy CMAS deposit on the Al2TiO5 layer revealed the largest equilibrium contact angle and slowest diffusion-limited spreading rate among all the samples.