Effect of nodal mass on macroscopic mechanical properties of nanoporous metals

Abstract

The current work investigates the effect of the nodal mass on the macroscopic mechanical behavior of nanoporous metals using the Finite Element Method. A nodal corrected beam modeling concept is introduced that allows local incorporation of the effective elastoplastic mechanical behavior of the nodal mass in the nodal area of a representative volume element (RVE). The calibration to the corresponding Finite Element solid model is achieved by integrating additional geometry and material parameters to the so-called nodal areas in the beam model. With this technique an excellent prediction can be achieved over a large range of deformation for different types of RVEs. From the results of the nodal corrected beam model, modified leading constants are determined in the scaling laws for Young's modulus and yield strength. The effect of the nodal correction is also studied with respect to various randomization levels. Finally, the ligament size dependent strength is analyzed by applying the proposed model to experimental data. It could be shown that the nodal correction improves the overall agreement with literature data, particularly for such data points that are related to samples with a high solid fraction.