Foam Stress Strain Resilience
firmness, stiffness, stress, strain, resilience, instant springiness, thickness
Foams are used for thousands of different applications and can be very complex, with highly varied degrees of firmness, resilience, relaxation, creep, and fatigue behaviors. Single firmness metrics, such as the PSI firmness values listed in catalogs, do not provide enough information to determine which foam might be best for specific applications. This application study introduces a few additional metrics that can be extracted from a simple compression test. The tests were conducted on sample packs that were purchased from an online supplier.