Strain-gradient dependent fatigue behavior of micron-thick copper single crystal foils

The experimental observations on dislocation structures in the micron-thick cantilever beam-type samples of copper single crystals subjected to symmetrically-reversed bending load and the theoretical simulations using the modified reaction–diffusion model were conducted. It was found that strain-gradient introduced by inhomogeneous deformation has a strong influence on dislocation patterning behavior, cyclic deformation response and fatigue life of the micron-thick copper single crystal beams. The simulation results provide a deep insight into the effects of the geometrical scale and the strain gradient on fatigue behaviors in micron-thick metal foils subjected to symmetrically-reversed bending load.