Superlattice effect for enhanced fracture toughness of hard coatings

By R. Hahn, M. Bartosik, R. Soler, C. Kirchlechner, G. Dehm, P. Mayrhofer. 2016

178 citations recorded by the source corpus.

Abstract Coherently grown nanolayered TiN/CrN thin films exhibit a superlattice effect in fracture toughness, similar to the reported effect in indentation hardness. We found –by employing in - situ micromechanical cantilever bending tests on free-standing TiN/CrN superlattice films– that the fracture toughness increases with decreasing bilayer period ( Λ ), reaching a maximum at Λ  ~ 6 nm. For ultrathin layers ( Λ  ~ 2 nm), the fracture toughness drops to the lowest value due to intermixing and loss of superlattice structure. Both, fracture toughness and hardness peak for similar bilayer periods of TiN/CrN superlattices.

Subfields: Materials Chemistry, Mechanics of Materials

View Paper: https://www.semanticscholar.org/paper/cea3bafcdc3be1ddc6c3432680e23ec6128092ae