Size dependence of buckling strains of Cr films, Cu films and Cu/Cr multilayers on compliant substrates

Abstract The buckling strain e B of Cr films and Cu films exhibits opposite film thickness h dependence: the e B of Cr films decreases monotonically, while the e B of Cu films increases monotonically with the increasing h . The delamination of Cr films follows the strain energy criterion while the Cu films are buckle-limited. The e B of Cu/Cr nanostructured metallic multilayers (NMMs), much higher than that of Cr films, increases as the modulation period λ increases. A modified strain energy criterion involving interfacial adhesion and plastic deformation has been developed to describe the evolution of e B of Cu/Cr NMMs with λ .