Effect of reactive elements in MCrAlX bond coat for durability improvement of thermal barrier coatings

• Published in: Corrosion science Vol. 237; p. 112329
• Main Authors: Negami, Masahiro, Morihashi, Ryo, Yoshino, Tessei, Sahara, Ryoji, Yamabe-Mitarai, Yoko
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 15.08.2024
• Subjects: First principles calculation; High temperature oxidation; Reactive elements; Thermal barrier coatings; Thermally grown oxide; Thermal barrier coatings; Thermally grown oxide; Reactive elements; First principles calculation; High temperature oxidation
• ISSN: 0010-938X
• DOI: 10.1016/j.corsci.2024.112329

The effects of reactive elements (RE) in MCrAlX alloy (M: Metals, X: RE) as the bond coat for thermal barrier coatings durability were investigated by both experimental evaluation and density functional theory (DFT) calculations. Cyclic oxidation tests showed that the lifetime of the sample with Y, Hf, and Si as RE displayed approximately twice of the sample with Y only. Furthermore, the interface energies between oxide (α-Al2O3) and bond coat with various RE (Si, Sc, Ti, Y, Zr, Hf, La, and Ce) were calculated by DFT. DFT results indicate that Hf and Si doping effectively reduce the interface energy. [Display omitted] •Cyclic oxidation life of thermal barrier coating was experimentally evaluated.•Hf and Si addition to bond coat improved the durability of thermal barrier coatings.•Reactive elements effects were evaluated by density functional theory calculations.•Origin of reactive elements effects on the interfacial energy is clarified.•Doped Si and Hf at the interface effectively reduce the interface energies.