Orientation dependent fracture behavior of nanotwinned copper

Columnar grown nanotwinned Cu was tensile tested in-situ inside the TEM in combination with automated crystal orientation mapping scanning transmission electron microscopy to investigate the active deformation mechanisms present in this material. Two tensile directions were applied, one parallel to the twin boundaries and the other perpendicular to the twin boundaries. In case of tensile testing perpendicular to the twin boundaries, the material deformed by detwinning and the formation of new grains, whereas in the parallel case, no new grains were formed and the fracture happened along the twin boundaries and a boundary that has formed during the deformation. (C) 2015 AIP Publishing LLC