Library Subscription: Guest
Begell Digital Portal Begell Digital Library eBooks Journals References & Proceedings Research Collections
International Journal for Multiscale Computational Engineering

Impact factor: 1.103

ISSN Print: 1543-1649
ISSN Online: 1940-4352

International Journal for Multiscale Computational Engineering

DOI: 10.1615/IntJMultCompEng.v5.i3-4.50
pages 227-242

A Parametric Domain Map for Top Coat Damage Initiation and Propagation in EB-PVD Thermal Barrier Coatings

Himanshu Bhatnagar
Department of Mechanical Engineering, The Ohio State University, Columbus, OH 43210, USA
Mark E. Walter
Department of Mechanical Engineering, The Ohio State University, Columbus, OH 43210, USA
Somnath Ghosh
Department of Civil Engineering, Johns Hopkins University, Baltimore, Maryland 21218, USA

ABSTRACT

Despite providing superior protection of engine components from severe temperatures, thermal barrier coatings are susceptible to catastrophic failure due to large-scale interfacial delamination. Under operating conditions, interfacial waviness increases due to bond coat creep and the cyclic nature of the thermal loading. Recent analyses show that the top coat incurs cracks at the sites of interfacial undulation. The top coat cracks propagate and coalesce under cyclic thermal load, which leads to catastrophic interfacial delamination. In this article, a finite element model of the thermal barrier coating (TBC) system is developed in the commercial code ABAQUS to investigate dependencies on various parameters and to develop a simplified parametric understanding of the top coat crack initiation and propagation. A parametric domain map for assessing crack initiation and propagation is developed in terms of geometric parameters of the TBC. Thus the domain map identifies which TBC geometries yield a fail-safe