ABSTRACT
All materials and hence structures contain damping. For applications where sound and vibration are present, increased damping is desired to attenuate the unwanted vibration. However, in other applications such as rolling wheels and belt drive system high levels of damping are undesired. While the primary focus of this section will be to look at situations where damping is desired, the same analysis and application principles will apply to systems where damping is detrimental to performance. Metallic materials often have very low levels of damping. Typically, the loss modulus will be on the order of 0.1–1.0% of the storage modulus. However, polymeric materials will typically have loss moduli in the range of 1–200% of the storage moduli. Thus, a polymeric or polymeric composite material will damp vibration much more effectively than a metallic material.
