The mechanical response of LDPE foam on compression: modelling and compressive deformation mechanism

Abstract

A tetrakaidecahedral cell model has been utilized and simulated using SolidWorks CAD system to predict the compressive stress behavior of closed-cell structure polyethylene foam. Foam was prepared by melt compounding a pre-determined expandable formulation using a thermostatically controlled heated two-roll mill and foamed using compression molding technique via a single stage foaming process at 175°C. The physical and mechanical properties such as density, cell size, cell walls thickness, and compression behavior were evaluated and the results were used as input parameters in the intended simulation. Stress analysis was performed on the model using static analysis and the results were verified with the experimental results. It is noted that the cell morphology parameters such as cell size and cell wall thickness have a significant influence towards the cell deformation. Progressive cells deformation mechanism was also monitored and recorded in real-time with respect to percentage of strain. Results indicated that larger cell with thinner cell walls experienced much greater compression than smaller cell with thicker cell walls.