Plastic Behavior of Metals in the Strain-Hardening Range. Part II

In order to observe the behavior of a material under various conditions of strain-hardening, copper bars were tested in tension, in compression and in torsion. The results of the different tests were plotted on the same set of coordinates as a means of correlation. The shearing stress in the octahedral planes was used as ordinates and the corresponding octahedral shearing strain was used as abscissae. Good agreement was found between the curves for tension, compression, and torsion for small strains, but for very large strains (as obtained near the ultimate strength of annealed copper) the curves tend to separate to a marked degree. Hardness readings were also taken to check the relation between hardness and strain.