On Creep and Relaxation. II.

A phenomenological theory of the elastic aftereffect can be formulated with the aid of the principle of superposition. In a previous paper the theory of the transient effects, caused by the sudden application of a constant load or a constant deformation, has been developed. In the present paper the theory of the steady-state behavior under alternating load and deformation is given. Relations are established between the loss factor, the storage factor, the distribution functions, and the Laplace transforms of the creep—and the relaxation—function.