Scaling laws governing the erosion and impact resistance of thermal barrier coatings

On cracks and delaminations of thermal barrier coatings due to indentation testing: Experimental investigations

“…6 and 7). Similar shear bands have been observed upon indentation with a spherical indenter at high temperature [20], and in coatings on air foils after foreign object damage [21] and erosion [22]. The shear bands appeared clearer and straighter in the as-coated TBC system than in the aged specimens (for the same maximum indentation force).…”

Protectiveness of Pt and Gd2Zr2O7 layers on EB-PVD YSZ thermal barrier coatings against calcium–magnesium–alumina–silicate (CMAS) attack

“…Cross-section image of Gd 2 Zr 2 O 7 /YSZ coatings after heat-treatment at 1250 1C for 4 h with CMAS deposits (a), and the element maps Ca (b), Mg (c), Al (d), and Si (e). [6][7][8][9][10][11], Y is found to be depleted, possibly due to the effect of the CMAS infiltration. In area near the YSZ/TGO interface (area 11), quite high amount of Ca, Mg, Al and Si elements are detected, indicating that CMAS has penetrated throughout the GZO/YSZ coatings.…”

“…The main components of the ingested particles are calcium-magnesium-aluminum-silicon (CMAS). At low temperatures, CMAS particles lead to erosive wear or local spallation of TBCs [8,9]. As temperature increases, CMAS melts and penetrates into the coating, which causes TBC degradation and leads to the loss of insulation efficiency [10][11][12][13].…”

Experiments and numerical simulations of single particle foreign object damage-like impacts of thermal barrier coatings

“…As the particle penetrates into the TBC, plastic deformation occurs, leading to densification and column bending. The deformation is often accompanied by shear bands, which extend diagonally downward and, in some cases, induce delamination along the interface with the TGO [3,5].…”