Particle induced gamma and X-ray emission spectroscopies of lithium based alloy coatings

Lithium based inhibitors in aerospace coatings are seen as excellent replacements for their chromium counterparts which are both carcinogenic and heavier. However, Li is generally difficult to detect and following changes in its distribution due to corrosion is impossible with many standard techniques. Combining MeV Particle Induced Gamma and X-ray emission provides a powerful tool and in this paper we summarise some recent experiments on such coatings using the CSIRO Nuclear Microprobe. PIGE mapping of the LiCO3 particles and their patterning illustrates how the method will be extremely useful in monitoring surface corrosion.