Papers by Author: Milan J. Konstantinović

Abstract: The effect of Cu-precipitation on the dislocation dynamics is studied by internal friction and magnetic after-effect measurements of thermally aged Fe1%CuC. We found that the copper precipitation in these alloys is accompanied by carbon redistribution. The results of both experiments showed that the hardening regime is governed by an increase of the dislocation density due to the growth of copper precipitates, while in the softening regime carbon redistribution plays a major role.

Abstract: By comparing the properties of dislocation-related relaxation processes in internal friction spectra and the tensile data of various iron alloys, we found that the temperature dependence of the flow stress is governed by the total distribution of the activation energies of dislocation motion. The derived model explains the origin of an anomalous temperature dependence of the flow stress in thermally aged Fe-1%Cu alloys, and Fe-x%Cr alloys as a function of Cr concentration, as well as the non-uniform temperature dependence of the flow stress in pure Fe.