Citation:
B. Tryon, Q. Feng, R.G. Wellman, K.S. Murphy, J. Yang, C.G. Levi, J.R. Nicholls, T.M. Pollock, Multi-layered Ruthenium-modified Bond Coats for Thermal Barrier Coatings, Metallurgical and Materials Transactions A, Volume 37, Number 11, November 2006, Pages 3347-3358
Abstract:
Diffusional approaches for fabrication of multi-layered Ru-modified bond coats for thermal
barrier coatings have been developed via low activity chemical vapor deposition and high activity
pack aluminization. Both processes yield bond coats comprising two distinct B2 layers, based on
NiAl and RuAl, however, the position of these layers relative to the bond coat surface is reversed
when switching processes. The structural evolution of each coating at various stages of the
fabrication process has been and subsequent cyclic oxidation is presented, and the relevant
interdiffusion and phase equilibria issues in are discussed. Evaluation of the oxidation behavior of
these Ru-modified bond coat structures reveals that each B2 interlayer arrangement leads to the
formation of α-Al 2 O 3 TGO at 1100°C, but the durability of the TGO is somewhat different and in
need of further improvement in both cases.
