Friction and source hardening in irradiated mild steel

The effect of neutron fluence on stress-strain behavior of mild steel at ambient temperature revealed that Luders strain increases with fluence and at the highest fluence employed here namely 1.4x1019n/cm2 fracture occurred during Luders propagation. The lower yield stress increased as cube root of fluence and friction stress increased as square root of fluence. The interstitial impurity atoms (C and N) combine with irradiation induced defects thereby resulting in reduced net concentration of free C and N in solution and thus the source pinning effect decreases in irradiated steels as observed here. The increase in Luders strain with the corresponding decrease in source hardening resulted in reduced work-hardening in irradiated steels as expected