Friedel oscillations are limiting the strength of superhard nanocomposites and heterostructures.
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.
Zhang
R F
RF
Department of Chemistry, Technical University Munich, Lichtenbergstrasse 4, D-85747 Garching, Germany.
Argon
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AS
Veprek
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