Effect of strain, temperature, and atomic order on slip deformation in FeCo

Abstract

A detailed investigation of the low temperature deformation behavior of ordered and disordered FeCo was carried out in order to determine the effect of strain and atomic ordering on the rate controlling processes involved therein. The results clearly indicate that the activation energies and activation volumes for the ordered alloy in Stage III, and for the disordered alloy, as well as for iron, are the same. From this, it is concluded that the dislocations are uncoupled in Stage III of the ordered alloy and the overcoming of the Peierls stress by the uncoupled dislocations could be responsible for the temperature dependent flow stress in both ordered and disordered alloys. The ordered alloy at low strains and the disordered alloy at high strains show deviations from the normal Arrhenius behavior, and these deviations are related to the possible existence of non-uniform dislocation structures in these alloys.