Microstructure and yield strength of severely deformed silver

High-purity silver was processed by equal-channel angular pressing (ECAP) to eight passes, giving an average grain size of similar to 250 nm. The densities of dislocations and twins were measured and compared with reported values for other face-centered cubic metals processed by ECAP. The results show the saturation yield strength correlates to the dislocation density according to the Taylor equation, and that the value of the geometrical parameter a in the Taylor equation is strongly influenced by the stacking fault energy.