The deformation of copper single crystals at 4.2 °K

The evolution of the defect structure in copper single crystals during tensile tests at 4.2 °K, was investigated by means of in situ measurements of resistivity, mechanical response and TEM observations. The results suggest that dipoles created during deformation represent an early annealable component of the overall resistivity. Twinning produces both a transformation of the dislocation structure and effectively converts the material into a composite. Final shear instability occurs on the twin-matrix interface.