Surface directed spinodal decomposition at TiAlN / TiN interfaces
(English)Manuscript (preprint) (Other academic)
In contrast to the monolithic c-Ti1-xAlxN, the isostructural spinodal decomposition to c-AlN and c-TiN of the c-Ti1-xAlxN/TiN multilayers have the same onset temperature regardless of composition (x=0.50 and 0.66). The onset is also located at a lower temperature compared to the monoliths with the same Al-content, revealed by differential scanning calorimetry. Zcontrast STEM imaging shows a decomposed structure of the multilayers at a temperature where it is not present in the monoliths. Atom probe tomography reveal the formation of an AlN-rich layer followed by a TiN-rich area parallel to the interface in the decomposed Ti0.34Al0.66N/TiN coating, consistent with surface directed spinodal decomposition. Phase field simulations predict such behavior and show that the surface directed spinodal decomposition is affected by in the internal interfaces, as deposited elemental fluctuations, coherency stresses and alloy composition.
Surface directed spinodal decomposition, Titanium aluminium nitride, Phase field simulations, Atom probe tomography
IdentifiersURN: urn:nbn:se:liu:diva-84704OAI: oai:DiVA.org:liu-84704DiVA: diva2:561227