Damping mechanisms and phenomenology in materials

Abstract

Definition of damping. Sensitive Theological measurements reveal that perfect elasticity is almost never observed in materials and structures even at low stress. Under cyclic loading inelasticity leads to a stress-strain relation that is not a single-valued function but instead forms a hysteretic loop (see Fig. 1 and Table 1). The area within the loop is proportional to the energy dissipated per cycle of loading, a property identified by the term “damping” or “internal friction” in this paper. This definition of damping specifically excludes energy transfer devices such as dynamic absorbers or so-called dynamic “dampers”; energy must be absorbed within the specified system before the term damping is applicable.