Why use rubber material in vibration dampers ?

Vibration dampers is mechanical part that absorb energy from working condition. The ability to absorb energy is dependent on the damping of material. Rubber material have high damping when compared with other material thus it has been used as material in vibration dampers . Its properties that indicate high damping is energy absorption. Which must be considered in the design of vibration dampers. Energy absorption must define with specific energy , some time referred to inadvisably as energy density, is the capacity to store elastically the spring energy U which is absorbed by 1 kg of spring mass. It is calculated from

Usp = U/m (J/kg)

where m is the mass of the spring material. Table 1 shows that the specific energy storage of a rubber spring is greater than that of steel. This mean that in practice the use of rubber material represents an appreciable saving in weight. Specific energy storage is greater in simple shear than in compression or tension. The best performance is shown by rubber material which are subjected simultaneously to shear and compression, yielding both the best exploitation of material and highest endurance strength.

Table 1 Specific energy Usp of rubber material in comparison with steel

Table 1 shown that vibration dampers that absorb energy depends on material and type of loading. In design vibration dampers must be consider type of loading which affect in performance of vibration dampers.