TY - JOUR
T1 - Atomic insights on intermixing of nanoscale nitride multilayer triggered by nanoindentation
AU - Chen, Zhuo
AU - Zheng, Yong Hui
AU - Löfler, Lukas
AU - Bartosik, Matthias
AU - Nayak, Ganesh Kumar
AU - Renk, Oliver
AU - Holec, David
AU - Mayrhofer, Paul Heinz
AU - Zhang, Zaoli
N1 - Publisher Copyright:
© 2021 The Author(s)
PY - 2021/5/21
Y1 - 2021/5/21
N2 - Mechanical properties of nanoscale multilayer coatings are to a large extent governed by the number of interfaces and their characteristics. While for a reduced layer thickness, increasing strength and toughness values have been reported, properties degrade for layer thicknesses of just several nanometers. Here, we report on an entirely overlooked phenomenon occurring during the indentation of nanolayers, presumably explaining the degradation of properties. Nanoindentation, commonly used to determine properties of hard coatings, is found to disrupt and intermix the multilayer structure due to the deformation imposed. Detailed electron microscopy studies and atomistic simulations provide evidence for intermixing in an epitaxial transition metal nitride superlattice thin film induced by nanoindentation. The formation of a solid solution reduces the interfacial density and leads to a sharp drop in the dislocation density. Our results confirm that plastic deformation causes the microstructure instability of nitride multilayer, which may further improve our understanding of multilayer strength mechanisms.
AB - Mechanical properties of nanoscale multilayer coatings are to a large extent governed by the number of interfaces and their characteristics. While for a reduced layer thickness, increasing strength and toughness values have been reported, properties degrade for layer thicknesses of just several nanometers. Here, we report on an entirely overlooked phenomenon occurring during the indentation of nanolayers, presumably explaining the degradation of properties. Nanoindentation, commonly used to determine properties of hard coatings, is found to disrupt and intermix the multilayer structure due to the deformation imposed. Detailed electron microscopy studies and atomistic simulations provide evidence for intermixing in an epitaxial transition metal nitride superlattice thin film induced by nanoindentation. The formation of a solid solution reduces the interfacial density and leads to a sharp drop in the dislocation density. Our results confirm that plastic deformation causes the microstructure instability of nitride multilayer, which may further improve our understanding of multilayer strength mechanisms.
UR - http://www.scopus.com/inward/record.url?scp=85107296826&partnerID=8YFLogxK
U2 - 10.1016/j.actamat.2021.117004
DO - 10.1016/j.actamat.2021.117004
M3 - Article
SN - 1359-6454
VL - 214.2021
JO - Acta materialia
JF - Acta materialia
IS - 1 August
M1 - 117004
ER -