Classification of slip system interaction in microwires under torsion

Microwires have become of increasing interest for the miniaturization of structural components. A profound understanding of the deformation behavior of microwires is important for the assessment of their applicability and lifetime in specific components. In particular, the deformation behavior under torsional loading and the associated microstructure evolution are of interest. The exact involvement of individual slip systems and their activities in the complex stress field under torsional loading are mostly unknown. In this paper, the microstructure evolution of single crystalline gold microwires under torsion have been analyzed for the high-symmetry crystal orientations (100), (110), and (111) using simulation and experimental results. It is shown that a classification of the slip systems can be derived a priori by theoretical considerations. It is found, that the slip system activity, stress relaxation mechanism, as well as screw and edge composition of the piled-up dislocation density depends on specific slip system groups. Furthermore, the misorientation and its rotational axes including the identification of the slip system activities are discussed.