Topology and mechanics of metal rubber via X-ray tomography

This paper describes the structural characteristics of metal rubber (MR) evaluated by X-ray tomography and skeletonisation at microscopic scale. The parameters used to describe the internal structure of the MR were numerically extracted and compared to assess the effect of different MR manufacturing parameters on the mechanical properties of the material. Quasi-static tests were also performed to obtain the stiffness and damping of the metal porous material and to understand their correlation with the topology defining the samples. A simplified helix cell model was used to interpret the mechanical properties of the MR based on the structural parameters identified in this paper. The transverse isotropic stiffness of the MR observed here is partly caused by the distribution of the metal wires, with more helices oriented along the molding direction resulting in smaller equivalent stiffness. The compression, relative density, helix and wire diameters can influence the structural and mechanical characteristics of the MR in a significant manner. [Display omitted] •Metrics are defined to quantitatively describe the internal microstructure of metal rubber•The transverse isotropy of the wire orientation in metal rubber is observed and quantified•The mechanical properties are here explained by combining a reduced order helix cell model and the internal structural characteristics•The effect of different manufacturing parameters on the mechanical properties and microstructures of metal rubber are tested and analyzed•The metal rubber wire diameter has the largest effect on the structural and mechanical isotropy of this porous material