|
The modern instrumental methods evaluated in this study had
several features in common. They all involved placing the sample
to be analysed in a vacuum chamber and irradiating the surface
with charged particles or electromagnetic radiation. This results
in the emission of radiation or particles characteristic of the
surface being analysed. Four different methods of analysis were
evaluated all of which are commercially available.
The techniques were evaluated by using them to investigate 14
separate analytical problems, four of which were real and the
remainder contrived. Contrived problems were created by taking a
paint of known composition and deliberately causing some surface
defect or contamination. In all cases the problems were intended
to be representative of actual analytical problems encountered at
PRA.
Evaluation of the results obtained from the 14 experiments
showed that two of the four techniques; Auger Electron
Spectroscopy and Secondary Ion Mass Spectroscopy could have some
limited application to coatings analysis. In contrast, the two
remaining techniques; Scanning Electron Microscopy - Energy
Dispersive Spectroscopy (SEM-EDS) and X-ray Photoelectron
Spectroscopy (XPS) were both shown to be capable of providing a
wealth of information regarding the nature of paint and substrate
surfaces. In particular, the unique ability of XPS to detect
small amounts of silicone contaminants on the surface of silicate
extended paints is regarded as a significant advance in the field
of surface coatings analysis.
Further Information
If you are interested in this, or any other project, please contact Richard Holman.
|
