Not to dampen your spirits, but until recently the state of testing for the damping properties of rubber was weak. Damping is a property that reduces the amplitude of even prevents oscillations in a system by a mechanism that opposes the changes in it. Simply put, damping represents a material’s capacity for energy absorption. In a wide variety of modern applications, rubber damping material is used for shock absorption or anti-vibration because of its unique viscoelastic properties. To reach different levels of shock absorption, rubber material needs to have corresponding damping properties such as stiffness and damping coefficient, and must be able to meet those needs over a wide temperature range. Therefore, the analysis of damping properties is of primary concern in designing rubber absorbers. 

Damping capability is influenced by many factors such as the nature of material, modulus, frequency, and temperature. Rubber absorbers and anti-vibration systems are usually used in a wide range of temperatures and frequencies, which have profound impact on the material’s damping capabilities. If the temperature decreases or frequency increases enough, rubber absorbers will become very stiff and brittle, losing much of their damping properties and resulting in little or no shock absorption. Glass transition temperature Tg or brittleness temperature Tb are often used to evaluate those properties. Generally, all rubbers have their Tg or Tb below room temperature. 

To determine these properties of the rubber material, many methods or instruments are used, such as the rebound tester, and dynamic and static stiffness tester. However, these test methods have a hard time keeping up with a production environment where testing not only requires timely analysis but also a high level of accuracy and repeatability. It’s clear that a more accurate and efficient testing method to predict damping properties of rubber material is urgently needed.