Materials with Memory: Viscoelasticity and Hysteresis

The paper is devoted to the modelling of materials with memory. Preliminarily some historical developments of viscoelasticity are considered, thus providing a relevant example of material with memory. Next a new approach to the use of the second law, as a restriction on the constitutive equations, is shown to allow a decisively more general setting of materials models. In this setting a far reaching scheme of hysteretic properties is established.