Journal ArticleDOI
Modeling Oxidation Induced Stresses in Thermal Barrier Coatings
Reads0
Chats0
TLDR
In this paper, a finite element model was developed to evaluate stresses induced by thermal cycling of a typical plasma sprayed thermal barrier coating (TBC) system and it was found that oxidation of the bond coat had a strong effect on ceramic layer stresses and that oxidation induced stresses were influenced by other factors, such as bond coat creep, top coat creep and bond coat roughness.Abstract:
Oxidation of the bond coat of a thermal barrier coating (TBC) is an important contributing factor to spallation of the ceramic top coat during service. However, the mechanisms by which oxidation facilitates TBC failure are poorly understood. It is also unclear how oxidation may interact with other potential degradation mechanisms. A finite element model was developed to evaluate stresses induced by thermal cycling of a typical plasma sprayed TBC system. It was found that oxidation of the bond coat had a strong effect on ceramic layer stresses and that oxidation induced stresses were influenced by other factors, such as bond coat creep, top coat creep and bond coat roughness.read more
Citations
More filters
Journal ArticleDOI
Thermal Barrier Coatings for Gas-Turbine Engine Applications
TL;DR: In this article, the structure, properties, and failure mechanisms of thermal barrier coatings (TBCs) are reviewed, together with a discussion of current limitations and future opportunities.
Journal ArticleDOI
Understanding plasma spraying
TL;DR: In this paper, a summary of the actual knowledge in plasma spraying with an emphasis on the points where work is still in progress is presented, including: the plasma torches with the resulting plasma jets and their interactions with the surrounding environment, powder injection with the heat, momentum and mass transfers between particles and first plasma jets, the particles flattening and solidification, forming splats which then layer to form the coating.
Journal ArticleDOI
Development of a micromechanical life prediction model for plasma sprayed thermal barrier coatings
TL;DR: In this article, a finite element method (FEM) is used to calculate stress development during thermal loading and these results can then be introduced into a crack propagation model to estimate crack development during the thermal cycling operation.
Journal ArticleDOI
Finite element analysis of stress distribution in thermal barrier coatings
TL;DR: A numerical simulation of crack development within APS TBC systems is presented in this article, revealing a small influence influence of both on the stress state in the thermal barrier coating system subjected to temperature loading.
Journal ArticleDOI
Damage mechanisms and lifetime behavior of plasma-sprayed thermal barrier coating systems for gas turbines — Part II: Modeling
TL;DR: In this article, detailed damage analysis of a plasma sprayed ZrO 2 /8 ¾wt −% Y 2 O 3 -MCrAlY-CMSX-4 TBC system during isothermal and cyclic oxidation tests with different dwell times at high temperature have been performed.
References
More filters
Book
Fracture Mechanics of Ceramics
TL;DR: In this article, a linear-elastic fracture mechanics can be applied to describe the failure behavior of small flaws in ceramic materials, which is caused by the extension of small faults.
Journal ArticleDOI
Failure mechanisms of thermal barrier coatings exposed to elevated temperatures
Robert A. Miller,Carl E. Lowell +1 more
TL;DR: In this paper, the failure of a ZrO2-8%Y2O3/Ni-14% Al-0.1% Zr coating system on Rene 41 in Mach 0.3 burner rig tests was characterized.
Journal ArticleDOI
Oxidation‐Based Model for Thermal Barrier Coating Life
TL;DR: In this paper, a procedure for modeling the lives of thermal barrier coatings subjected to high-temperatrue environments is described, based on the assumption that oxidation is the single important time-dependent factor which limits the life of these coatings, and that oxidation-induced strains combine with cyclic strains to promote slow crack growth in the ceramic layer.
Journal ArticleDOI
On the mechanical behavior of brittle coatings and layers
TL;DR: In this article, the authors examined several important issues concerning the mechanical properties of coatings, films, and layers and described the conditions needed to induce buckling and subsequent spalling.
Related Papers (5)
A numerical model for the cyclic instability of thermally grown oxides in thermal barrier systems
Anette M. Karlsson,A.G. Evans +1 more
Failure mechanisms associated with the thermally grown oxide in plasma-sprayed thermal barrier coatings
Afsaneh Rabiei,A.G. Evans +1 more