Scaling Relationships in Spherical Indentation of Metallic Foams

Metallic foams are a new class of functional materials. They have found their application as sandwich cores in lightweight structures and have the potential as implant materials in bioengineering. To characterize the mechanical properties of these materials becomes an interesting and relevant research topic. In the mean time, indentation method has been well accepted as a simple and effective way to measure the mechanical properties of solid materials. We believe that it is possible to study the averaged mechanical properties of a metallic foam from a spherical indentation test. In this paper, theoretical investigation to understand the spherical indentation responses of metallic foams is presented. Based on the dimensional analysis and finite element calculations, several scaling relationships in the indentation of metallic foams with a spherical indenter were obtained. These scaling relationships illustrate the dependence of the indentation response on the material properties of metallic foams, such as porosity and plastic deformation shape factor. These results provide the basis for further research to develop spherical indentation methods to measure mechanical properties of metallic foams.