The Experimental Exploration of Plastic Flow in Sheet Metals

During the past fifty years a good deal of attention has been paid to the development of mathematical theories of plastic behavior. These efforts have been well summarized in recent papers by Nadai (1), Prager (2), and their coworkers (3, 4), as well as by many others. The development of experimental data suitable for allowing a choice to be made among various theoretical possibilities has not kept pace with the mathematical developments. The purpose of this report is to present some data on plastic flow in some sheet metals and to show that, when anisotropy in real materials is taken into account, some of the current theory appears to correlate flow results very well both in accounting for the stress required to maintain flow and in describing the distribution of strain resulting from various stress systems.