Single-kink relaxation processes in iron–chromium binary alloys

The internal friction spectra in cold-worked pure iron and iron–chromium alloys are measured in the inverted torsion pendulum, operating at 1.8Hz and in the temperature range from 100K to 600 K. The addition of chromium, in combination with a plastic deformation, activates the relaxation process producing an internal friction peak at about 210K. The peak intensity exhibits a strong increase by increasing the concentration of solute atoms. On the basis of the estimated activation energy, Esk = 0.57 eV, and atomistic simulations, this mode is assigned to the single-kink relaxation process corresponding to the recombination of geometrical kinks formed as a result of Cr-dislocation core interaction in the 1/2 screw dislocations.