Mechanics in Material Space and Analysis of Defects

Abstract : The principal objective of this program was to contribute to the knowledge and understanding of complex structural degradation processes that occur in various parts of a structure, which may be subjected to a mechanical or thermal field, produced for instance, by an elevated temperature environment, or an electrical field as in piezoelectricity. Typical degradation processes involve void and crack formation and growth, dislocation motion, as well as solid state phase transformations and chemical reactions. It is now well recognized that it is the motion, evolution and rearrangement of such defects in solids that control and determine the response of structural materials to imposed external fields. It is thus most desirable to have available an improved methodology and techniques for understanding and predicting the tendency of these imperfections to form, move and evolve, and more importantly for linking the microscale structure to the macroscale behavior of the material.