The ratio of energy given up in recovery from deformation to the energy required to produce the deformation
The most widely used methods for measuring resilience by impact involve rebound in some form. A very simple test consists of dropping a metal ball from a known height onto a firmly supported rubber specimen and measuring the height of rebound, as with the Bashore Resiliometer.
Higher the rebound, the material is more “alive”. Lower the rebound the material is less elastic.
Urethane can be formulated to exhibit high or low resilience.
Urethane provides a greater hardness range with less sacrifice in resilience than many types of elastomers. This is a characteristic because urethanes are non-reinforced while rubber requires the use of fillers to develop optimum properties.
