High-Temperature Spallation Behaviour of High-Entropy System in Thermal Barrier Coatings

Wednesday, September 30, 2026: 9:40 AM
302B (Québec City Convention Centre)
Ms. Michelle Vincent Xavier , Concordia University, Montréal, QC, Canada
Ms. Hamideh Vakilifard , Concordia University, Montréal, QC, Canada
Ms. Farnaz Bayat , Concordia University, Montréal, QC, Canada
Dr. Rogerio S. Lima , National Research Council of Canada, Boucherville, QC, Canada
Dr. Hossein Shahbazi , Concordia University, Montréal, QC, Canada
Prof. Martin Pugh , Concordia University, Montréal, QC, Canada
Prof. Christian Moreau , Concordia University, Montréal, QC, Canada
High-Temperature Spallation Behaviour of High-Entropy System in Thermal Barrier

Coatings

Michelle Vincent Xavier1, Hamideh Vakilifard1, Farnaz Bayat1

, Rogerio S. Lima2

, Hossein Shahbazi1

, Martin D. Pugh1, Christian Moreau1

1 Department of Mechanical, Industrial and Aerospace Engineering, Concordia University,

Montreal, QC, H3G 1M8, Canada

2 National Research Council of Canada, 75 de Mortagne Blvd, Boucherville, QC, J4B 6Y4,

Canada

Corresponding: michellevincent.xavier@mail.concordia.ca, christian.moreau@concordia.ca

Abstract:

Thermal barrier coating (TBC) systems are multilayer coatings designed to protect hot-section

gas turbine components from extreme temperatures and oxidation; however, conventional

MCrAlY bond coat and yttria-stabilized zirconia (YSZ) topcoat systems exhibit durability

limitations under prolonged high-temperature thermal cycling, motivating the development of

next-generation TBC concepts. In this study, a high entropy TBC system composed of an

HVOF-deposited high entropy alloy bond coat (FeCoNiCrAl) and a suspension plasma sprayed

(SPS) high entropy zirconate (HEZ) topcoat with the chemical composition

(Y0.2Nd0.2Sm0.2Gd0.2Dy0.2)2Zr2O7was studied. In-625 was used as a substrat. A thin YSZ

interlayer was incorporated to improve interfacial compatibility. The high entropy TBC system

was subjected to 1-hour cyclic thermal exposures at 1150 °C until failure to assess its spallation

behaviour and structural stability. A conventional two-layered TBC with comparable

microstructures were used as a reference. These samples comprise an HVOF MCrAlY bond

coat and a SPS YSZ topcoat. The results provide insight into the influence of high entropy bond

coats and topcoats on the spallation resistance and thermal cycling durability of advanced TBC

systems.

Keywords:

Thermal spray, Suspension Plasma Spray, Thermal Barrier Coating, Topcoat, High Entropy

Zirconate, Spallation.

See more of: EBCs, TBCs, and Thermal Spray Coatings I
See more of: Thermal Spray Society (TSS) at IMAT