Abstract
Breaking the hardness-toughness trade-off has always been a critical issue for hard protective coatings. Rational materials design, which simultaneously incorporate multiple strengthening and toughening mechanisms, could provide pathways toward hard yet tough materials.In this study, (AlCrNbSixTi)N multicomponent nitride coatings with various Si content are fabricated via magnetron co-sputtering. Multi-dimensional strengthening and toughening mechanisms are found in thermodynamics-driven nanostructured (AlCrNbSixTi)N. Enhanced atomic packing, nanostructure formation, and microstructural modification originate from spinodal decomposition contribute to multiple strengthening and toughening mechanisms after Si incorporation. From atomic-level packing, spinodal-decomposed nanostructure, to microstructure, the evolutions are quantitatively characterized and correlated to mechanical properties. With the addition of 4.4 at% of Si, maximum hardness of 27.2 GPa is achieved while maintains high fracture toughness of 3.66±0.37MPam. On the other hand, the maximum fracture toughness is found for (AlCrNbSi7.6Ti)N and is attributed to the featureless microstructure, nanostructure formation and non-complete amorphization.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have