On the complexities of microband interactions in a cold-deformed goss-oriented Ni single crystal

Abstract

In this investigation, the three-dimensional nature of microband boundaries was investigated in a Goss-oriented Nickel single crystal. The sample was 30 pct deformed by plane strain compression and then characterized by several advanced techniques including three-dimensional electron backscatter diffraction (3D-EBSD) and transmission electron microscopy (TEM). In the longitudinal section of the sample, microbands were found to exhibit their classical strip-like appearance. However, the microband interfaces contain numerous curved features despite the average inclination of the interfaces closely matching the potential {111} slip planes. The microband boundary irregularities are argued to be the outcome of microband interactions, which are also linked to the orientation spread of deformation structures. Based on the detailed TEM investigation of the dislocation structures associated with intersecting microbands, it is argued that these interactions result in the disintegration and/or dissolution of microband boundary segments. A correlation between microband and cell boundaries was also found.