High-Temperature Solid Particle Erosion of Environmental and Thermal Barrier Coatings

Abstract

Solid particle erosion (SPE) is a common phenomenon observed in gas turbine engines. Particles entrained in the gas flow impact engine hardware, resulting in micro-scale damage that leads to deleterious effects such as material removal. For protective coatings, damage due to SPE is a key concern, since it can negatively affect the durability of the coating and subsequently the life of the underlying component. In this work, the high-temperature SPE behavior of two state-of-the-art environmental barrier coatings (EBCs) deposited via air plasma spray (APS) is investigated using alumina erodent to understand the effect of particle kinetic energy, impingement angle, and temperature. The SPE behavior of the EBCs is also compared to APS and electron beam–physical vapor deposition (EB-PVD) thermal barrier coatings (TBCs) to elucidate similarities and differences in the erosion response. The EBCs were more susceptible to SPE than the EB-PVD TBC but had greater SPE resistance compared to the APS TBC. Coating microstructure and porosity were shown to have a strong influence on the observed behavior.

Solid particle erosion in ceramic matrix composites and environmental barrier coatings: A perspective

“…Finally, it is observed that the chemical modifications to the M2Y EBC were not detrimental to the SPE resistance. In fact, the SPE resistance was slightly improved compared to the baseline Yb 2 Si 2 O 7 EBC 52 …”

“…It is expected that EBC/CMC components will replace at least some, if not all TBC/superalloy components in the hot section of gas turbines, so it is important to understand the relative erosion resistance between EBCs and TBCs. A comprehensive study was undertaken by the authors to compare the erosion rate of APS EBCs to APS and electron beam—physical vapor deposition (EB‐PVD) TBCs 52 . The study investigated a 100 wt.% Yb 2 Si 2 O 7 EBC (YbDS) and modified‐Yb 2 Si 2 O 7 EBC (M2Y) that consisted of balance Yb 2 Si 2 O 7 with additions of 1.39 wt.% mullite (3Al 2 O 3 ·2SiO 2 ) and 2.33 wt.% YAG (Y 3 Al 5 O 12 ).…”

“…A comparison of APS EBCs to APS and EB‐physical vapor deposition (PS‐PVD) 7YSZ thermal barrier coatings (TBCs) 52 …”

Tribology Characteristics of Heatproof Alloys at a Dynamic Pin Ladening in the Variable Temperature Field

“…Particulate erosion is a common phenomenon observed in gas turbine engines. Composites with a ceramic matrix are the main candidates for protecting components of hot sections of gas turbine engines [16,17]. Calculation of the thickness of protective coatings is usually a complex multi-criteria optimization problem due to the contradictions that arise between the goals of the task: achieving high thermal insulation characteristics, ensuring long-term operation, manufacturability and low manufacturing cost [18][19][20].…”