Following the successful application of electron beam (EB) physical vapour
deposition (PVD) thermal barrier coatings (TBCs) to moving parts of turbine
engines, the erosion resistance of these coatings has been of interest amo
ng researchers. However, although there are a number of papers on the erosi
on rate of these coatings, Little has been reported on their erosion mechan
ism. This paper provides observations on the erosion damage of EB PVD TBCs
and discusses the type of damage caused by erosion, as well as proposing a
possible mechanism of erosion. The aim of the project as a whole was to mod
el the erosion of EB PVD TBCs, but before modelling could begin, it was nec
essary to determine the erosion mechanism of these coatings.
It was found that in all cases examined, the erosion of the coatings procee
ds through the accumulation of damage in the form of horizontal cracks in t
he columns of the coating and subsequent removal of the fractured sections.
Since it appears as though the contact radius is important in the erosion
process, the effect of varying the elastic properties of the erodent and th
e target on the contact radius was assessed. (C) 2000 Elsevier Science S.A.
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