• Nonlinear behavior of 3D foams is featured in 3 regions – elastic, plateau and densification • 3D foams get higher compressive strength at high pore density with acetone solvent • Contact force in impact increases with increasing pore density. • Foams covered by acetone have highest compressive strength and elastic modulus Rigid polyurethane foam (RPUF) is widely used in engineering applications due to its superior mechanical and thermal properties. However, the influence of pore density and solvent exposure on its mechanical behavior under different loading conditions remains insufficiently understood. Therefore, this study aims to investigate the effect of pore density (20, 40, and 60 PPI) and solvents (acetone, ethanol, and methanol) on the compressive strength and elastic modulus of rigid polyurethane foam. Experimental tests were conducted to investigate these properties, and numerical simulations were performed using LS-DYNA under uniaxial compression and low-velocity impact loading conditions. The foam was modeled using a crushable foam model. In contrast, a piecewise linear plasticity model was used to simulate the upper face plate in compression simulation, and the impactor was modeled as a rigid body in the low-velocity impact simulations. The numerical analysis results were compared with experimental results to assess simulation accuracy. In addition, the effects of pore densities and solvents on compressive strength and elastic modulus were evaluated using two-way ANOVA after confirming the Shapiro-Wilk normality test. Based on the experimental results, the maximum compressive strength (147 kPa) was observed in 60 PPI foam covered with acetone. In contrast, the minimum compressive strength (20.2 kPa) was observed in 20 PPI foam covered with methanol. For elastic modulus, the maximum value (17.7 MPa) was observed in 40 PPI foam covered with acetone, while the minimum value (2.6 MPa) was observed in 20 PPI foam covered with methanol. Statistical analysis showed that pore density had a significant effect, whereas solvent had a marginal impact on compressive strength and elastic modulus (p<0.05).
Gurmu et al. (Tue,) studied this question.