ABSTRACT
The properties of metal have been studied ever since man discovered that he could change the hardness of steel by heating it to a bright cherry red and then quenching it in water or other suitable media. What happened to the metal was first theorized, but then, as instruments for study improved, facts replaced theory.1 Mechanical metallurgy as a fact-based science has since developed. For a long time, the impression was that, with progress in the physics of solids, the development of a physically based theory of plastic deformation of metals was just a matter of time, but that has not yet happened. In spite of great advances in the investigation of the nature of deformation, strength, and fracture of solids, a lot of problems related to the physics of these phenomena remain unresolved. It seems that within the scope of the conventional ideas their solution is not possible.
