An experimental method for a single layer is extended to determine the elastic properties of nanostructured W/C u multilayers on a flexible substrate.The strain difference between the W/Cu-polyimide-W/Cu composite and...An experimental method for a single layer is extended to determine the elastic properties of nanostructured W/C u multilayers on a flexible substrate.The strain difference between the W/Cu-polyimide-W/Cu composite and the uncoated substrate,measured by dual digital image correlation,allows us to extract the effective Young's modulus of W/Cu multilayers(20 periods)equaling 216±13 GPa.Finite element method is then performed,which agrees well with the experiment and classical rule of mixture(ROM)theory demonstrating that the extension to multilayers is effective and reliable.The numerical analysis also interestingly shows that the strain difference is linearly related to the thickness ratio(W/Cu),periods and sublayer thickness,respectively.In contrast to ROM theory,this approach could potentially be used for the evaluation of properties and design of emerging/unknown functional multilayers,whether or not they are crystalline or amorphous.展开更多
基金This research is financially supported by the National Natural Science Foundation of China(Grant 11802156)China Postdoctoral Science Foundation(Grant 2018M641331)French Government Program“Investissements d’Avenir”(Labex Interactifs,Grant ANR-11-LABX-0017-01).
文摘An experimental method for a single layer is extended to determine the elastic properties of nanostructured W/C u multilayers on a flexible substrate.The strain difference between the W/Cu-polyimide-W/Cu composite and the uncoated substrate,measured by dual digital image correlation,allows us to extract the effective Young's modulus of W/Cu multilayers(20 periods)equaling 216±13 GPa.Finite element method is then performed,which agrees well with the experiment and classical rule of mixture(ROM)theory demonstrating that the extension to multilayers is effective and reliable.The numerical analysis also interestingly shows that the strain difference is linearly related to the thickness ratio(W/Cu),periods and sublayer thickness,respectively.In contrast to ROM theory,this approach could potentially be used for the evaluation of properties and design of emerging/unknown functional multilayers,whether or not they are crystalline or amorphous.