S-N curves of copper single crystals

Abstract

Stress versus number of cycles curves are determined for copper single crystals by the method of constant stress amplitude. If the applied stress amplitude is expressed as shear stress on the most stressed initial slip system, the curves assume a form very similar to that reported earlier for polycrystalline f.c.c. metals. Orientation seems to have some effect on the fatigue life, so that the fatigue life is slightly shortened when the possibilities for multiple slip are increased. No mechanism change was evident at the stress amplitudes used, but some results supported the idea that this will be the case at stress amplitudes higher than the present ones.