ECI Digital Archives

Title

Environmental barrier coatings for SiC/SiC and Ox/Ox CMCs

Authors

Emine Bakan, Forschungszentrum Julich-IEK1, GermanyFollow
Robert Vaßen, Forschungszentrum Julich-IEK1, Germany
Daniel E. Mack, Forschungszentrum Julich-IEK1, Germany
Hagen Klemm, Fraunhofer Institute for Ceramic Technologies and Systems IKTS, Germany

Conference Dates

June 24-29, 2018

Abstract

Environmental barrier coatings (EBCs) are being developed for next-generation gas turbine engines to protect hot-section SiC/SiC or Ox/Ox (alumina-based) ceramic matrix composite (CMC) components in the harsh operating environments. In this paper, high-velocity water vapor recession (v=100m/s, P_O2=0.15atm T=1200°C) and thermal gradient cycling behavior (T_surface=1250°C) of thermally sprayed Yb₂Si₂O₇/Si EBCs on SiC using different processing conditions will be presented. Phase composition and microstructural changes in the coatings prior and after the tests will be examined.

Furthermore, the potential of different (Yb, Sc)-zirconate and hafnate compositions with high melting points as EBC materials will be discussed based on their investigated bulk properties. Characteristics of the solid-state synthesized materials, which were high energy ball milled into submicron particle sizes and subsequently densified with field assisted sintering technology (FAST), such as phase stability (HT-XRD), thermophysical (dilatometry, thermal diffusivity) and mechanical properties (hardness, indentation fracture toughness) will be demonstrated.

Recommended Citation

Emine Bakan, Robert Vaßen, Daniel E. Mack, and Hagen Klemm, "Environmental barrier coatings for SiC/SiC and Ox/Ox CMCs" in "Thermal Barrier Coatings V", Prof. Dr. Robert Vaßen, Forschungszentrum Jülich GmbH, Germany Brian Hazel, Pratt & Whitney, USA Prof. Dr. Uwe Schulz, German Aerospace Center, Germany Dr. Michael J. Maloney, Pratt & Whitney, USA Dr. Ram Darolia, GE Aviation (Retired), USA Eds, ECI Symposium Series, (2018). https://dc.engconfintl.org/tbcv/48