Estimates of interfacial properties in Cu/Ni multilayer thin films using hardness data

Modeling the defect structure and mechanical properties of metallic multilayer thin films requires estimates of dislocation parameters such as interfacial line energy and barrier strength, as well as resistance to confined layer slip. A method is presented to estimate these parameters using experimental measurements of hardness vs. individual layer thickness h. Application to Cu/Ni multilayers suggests that the interfacial line energy increases dramatically with h (5 ⩽ h ⩽ 50 nm), far in excess of values assumed in analytic and dislocation dynamics models.