Effects of modulation periods on mechanical properties of V/VN nano-multilayers

Metal/ceramic nano-multilayers, which possess the advantages of both metal and ceramics, have attracted intensive attention. In this work, the mechanical properties of V/VN nano-multilayers with different modulation periods (lambda s) were investigated using molecular dynamics simulations. The relationships between the microstructures and stress-strain (sigma-epsilon) curves during in-plane tension and out-of-plane compression were explored, and the effects of lambda were discussed. It shows that: (i) three kinds of V/VN nano-multilayers with different interfacial structures have different stabilities during deformation; (ii) dislocations nucleate firstly from the interfaces, propagate on {111} planes in VN layers, and deposit on the adjacent interface, and finally shift to V layers with the increase of applied strain; (iii) the nano-multilayer with larger lambda has larger elastic modulus, elastic limit and lattice integrity, and strain hardening and cracks would appear in the nano-multilayers with lambda > 42.90 angstrom.