Strain Rate and History Effects on the Deformation of Metals.

摘要

The work falls into two main categories: (i) The Endochronic Constitutive Theory and (ii) The Endochronic Theory of Fracture. Both these theories constitute significant innovations over what was the state of the art prior to their development. They are based on the concept of intrinsic time put forward by Valanis. Of far greater significance, however, is the fact that both theories have been demonstrate to be valid mathematical representations of material behavior as observed in the laboratory, and they unify, possibly for the first time constitutive and fracture behavior of metals. On the conceptual level they establish two conclusions: (a) The yield surface is not necessary for the description of plastic behavior and (b) History, yet rate independent behavior, can be formulated within the framework of the theory of thermodynamics of internal variables as formulated and developed by the principal investigator.