Real 3D Structure-Based Finite Element Simulation of Elastomer Foams: Effect of the Foaming Agent Content

In this study, elastomer foams based on natural rubber were fabricated using a one-step compression molding procedure to determine how the foaming agent (FA) content affects the morphological and mechanical properties of rubber foams. Finite element methods (FEMs) were used to simulate the uniaxial compression behavior of the foams at both the micro- and macrolevels. The results obtained from FEM analyses were then compared with the results of various hyperplastic models and experimental data. A continuous decrease in the cell size from 561 to 236 mu m (similar to 57%) and a gradual increase in the cell density from 32 to 469 cell/mm(3) (similar to 14 times) was observed with increasing the FA content from 2 to 10 phr via scanning electron microscopy (SEM) micrograph analysis. The key to building a real three-dimensional (3D) structure of the rubber foam is to combine several two-dimensional SEM micrographs. The produced real 3D structures revealed that a more uniform cell morphology and lower structural defects were observed in elastomer foam samples with a higher FA content. The mechanical results demonstrated an improvement in modulus (similar to 70%), hardness (similar to 107%), and resilience (similar to 67%) with increasing the FA content. The FEM analyses at the macroscopic level were in perfect agreement with the experimental data, with an average deviation of less than 6%. Additionally, the microlevel FEM analysis revealed a substantial reduction in the maximum amount of stress concentration and microstrain with a higher FA content.