Flexural behavior and microstructural material properties of sandwich foam core under arctic temperature conditions

This study investigates three types of foam core materials used in composite sandwich structures at various densities: H60, H100, F50, F90, PN115, PN200 and PN250. Three-point bending test is conducted to determine relationships between material and flexural properties at both room and low temperature Arctic conditions. X-ray micro-computed tomography is utilized to observe the microstructural relationships between foam density and mechanical properties of the core. This study evaluates Arctic temperature effects on mechanical properties for various types of foam core at varying densities with the intention for future Arctic applications. Although foam core materials become more brittle at a lower temperature, their flexural stiffness and flexural strength are further increased. However, due to the enhanced brittleness, the energy required for fracture is significantly reduced at low temperature conditions. This study utilizes statistical analysis to create contour plots and linear regression equations to predict flexural properties as a function of temperature and foam density. Molecular dynamics simulation is employed to verify experimental results to elucidate the effect of temperature on material behavior. This work provides a deeper understanding of how flexural strength relates to foam density, adding to existing data on foam strength properties under compressive, shear and tensile loads.