title: Friedel oscillations are limiting the strength of superhard nanocomposites and heterostructures.
abstract: To obtain a deeper understanding of the mechanism of plastic deformation and failure in superhard nanocomposites and heterostructures we studied, by means of the ab initio density functional theory, the stress-strain response and the change of the electronic structure during tensile and shear deformation of a prototype interfacial systems consisting of 1 monolayer SiN sandwiched between a few nm thick TiN layers. This shows that peak Friedel oscillations of valence charge density weaken the Ti-N interplanar bonds next to that interface, where decohesion in tension and slip in shear occurs. These results provide ways to design new, stronger and harder materials.
authors.affiliation: Department of Chemistry, Technical University Munich, Lichtenbergstrasse 4, D-85747 Garching, Germany.
authors.forename: R F
authors.initials: RF
authors.lastname: Zhang
authors.forename: A S
authors.initials: AS
authors.lastname: Argon
authors.forename: S
authors.initials: S
authors.lastname: Veprek