What is it about?
The degradation of an Electron Beam-Physical Vapour Deposition Thermal Barrier Coating caused by thermal cycling at 1150 degrees C has been followed in 3D non-destructively by time-lapse X-ray micro-computed tomography (mu-CT). Quantitative analysis of X-ray mu-CT virtual cross-sections on small samples is validated by destructive crosssectional scanning electron microscopy (SEM) micrographs of larger ones. The evolution of thermally-grown oxide (TGO) is quantified. The TGO/bond coat interface roughness is measured in 3D. No significant rumpling is observed. Undulations are found locally at the interface of the as-deposited sample. Such undulations can increase in amplitude during cycling providing locations for interfacial cracks to initiate. (C) 2018 Published by Elsevier Ltd on behalf of Acta Materialia Inc.
The following have contributed to this page: Professor Philip J Withers