A Constitutive Model of Metal Rubber for Hysteresis Characteristics Based on a Meso-Mechanical Method

Based on the typical mesoscopic structural characteristics of metal rubber, the mesoscopic physical mechanism was revealed through analyzing the spatial configuration and the contact mode of wire helixes for its compression deformation process. The mesoscopic structure unit based on the curved beam of variable length and the model of the contact interaction between curved beams were proposed. Combined with the distribution law of frictional contact points, a new constitutive model of metal rubber for hysteresis characteristics was established, which included its basic structure parameters such as the diameter and the elastic modulus of wire, the diameter of wire helix, and the relative density of metal rubber. The model could describe the restoring force curves of metal rubber in initial loading, unloading and repeated loading phases, and theoretically explained its elastic characteristics and dry friction damping characteristics of multipoint contact. To verify the theory model, a comparison was made between the theoretical results and the experimental results for metal rubber specimens with different relative densities. The results show that theoretic calculations are consistent with the experimental data, which will provides a theoretical basis for predicting the stiffness and damping of metal rubber and guiding its design.