The cyclic deformation and fatigue damage behaviours of [¯1414] oriented Ag single crystal were investigated in terms of cyclic stress-strain curves, surface slip morphologies and dislocation configurations. A clear plateau region appears in the cyclic stress-strain curve of the [¯1414] Ag single crystal over a strain range of 1.5 x 10-4 to 4 x 10-3, with average saturation shear stress amplitude of ∼26.6MPa. Corresponding ladder-like persistent slip bands also appear in the [¯1414] Ag single crystal. Compared with other Cu and Ag single crystals with single or double-slip orientations, the saturation resolved shear stresses of the critical double-slip-oriented single crystals, no matter whether for Cu or Ag, were significantly higher than that of the single-slip-oriented ones. Combining the two-phase model with the hindering effect of sessile jogs on screw dislocation movement, a three-phase model was proposed to rationalize the increase of saturation stress. In addition, the surface slip morphologies of the [¯1414] Ag single crystal were characterized by the interactions between the primary and secondary shear bands. According to the difference in their slippage, their interactions could be divided into three types, which could simultaneously appear in different local areas of the same crystal. The current experimental results extend the fundamental understanding of the intrinsic fatigue damage behaviours of face-centered cubic metal crystals.

Cyclic Deformation and Fatigue Damage Behaviors of [¯1414] Oriented Ag Single Crystal. P.Li, Z.F.Zhang, S.X.Li, Z.G.Wang: Philosophical Magazine, 2009, 89[32], 2903-20