On Experiments Revealing the Importance of Material Instability for Modern Theories of Plasticity

摘要

Based upon the dictates of observed response functions for the loading of fully annealed crystalline solids, and upon the definitions and concepts which arise from these same observations, a description and theory of large plastic deformation of metals is developed. With particular reference to recent and continuing experiments involving consideration of more than one non-zero stress component, herein is delineated the importance of material instability phenomena in the form of the Savart-Masson effect when two or more uncoupled incremental stress components are present, and in the form of finite deformation modes arising in second order transitions which occur at fixed shear angles. The experimental results and the general theory derived from them are shown to present new and interesting fundamental problems both for science and for technology in this field. (Author)