Abstract
A method for cleaning thermal barrier coatings (TBCs) contaminated during engine operation has been developed using laser ablation. Surface contamination on the turbine blades hinders nondestructive remaining life evaluation using photoluminescence piezospectroscopy (PLPS). Real time monitoring of the removed material is employed to prevent damage to the underlying coating. This method relies on laser induced breakdown spectroscopy (LIBS) to compute the cross correlation coefficient between the spectral emissions of a sample TBC that is contaminated and a reference clean TBC. The ablation process is stopped when the LIBS signal indicates the presence of the underlying TBC. It is shown that it is possible to remove targeted contaminants and cease ablation at top surface of the TBC. Subsequent microscopy images and PLPS measurements indicate that the integrity of the TBC has been maintained during the removal of surface contaminants.
| Original language | English |
|---|---|
| Pages (from-to) | 4614-4619 |
| Number of pages | 6 |
| Journal | Surface and Coatings Technology |
| Volume | 205 |
| Issue number | 19 |
| DOIs | |
| State | Published - Jun 25 2011 |
Bibliographical note
Funding Information:This work was conducted with the support of Rolls Royce Corporation and the National Science Foundation .
Funding
This work was conducted with the support of Rolls Royce Corporation and the National Science Foundation .
| Funders | Funder number |
|---|---|
| Rolls-Royce Corporation | |
| National Science Foundation (NSF) |
Keywords
- Contaminant removal
- Laser induced breakdown spectroscopy
- Non-destructive evaluation
- Photoluminescence piezospectroscopy
- Thermal barrier coatings
ASJC Scopus subject areas
- General Chemistry
- Condensed Matter Physics
- Surfaces and Interfaces
- Surfaces, Coatings and Films
- Materials Chemistry