Color Tint Etching
GUIDELINES
- Best results occur when etching right after polishing, time can create a passive surface
- Specimen preparation must remove all damage
- Etch the specimen with a general-purpose etch, then repolish and tint etch for best results
- Tint etching must be done by immersion, as swabbing will inhibit film formation
- The film grows epitaxially with the underlying grain structure with little “etch” depth
TINT ETCHING REVEALS
- Grains are colored according to their crystallographic orientation (film thickness is a function of crystal orientation)
- Very sensitive to chemical inhomogenieties
- Very sensitive to residual deformation
- Etchants are phase specific, i.e., selective