Effect of stacking fault energy on strength and ductility of nanostructured alloys: an evaluation with minimum solution hardening

The effect of stacking fault energy (SFE) on the mechanical properties was investigated in Ni–Co alloys which have minimum solution hardening effects. Cobalt reduces the SFE in nickel and this promotes grain refinement during processing and increases the dislocation and twin densities. A reduction in SFE increases strength and tensile ductility. The higher strength is due to grain refinement and higher dislocation and pre-existing twin densities whereas the higher ductility is attributed to a higher work hardening rate