Zeitschrift für Medienpsychologie

The Hall-Petch relationship was studied in interstitial-free steel subjected to Φ = 90° Equal Channel Angular Extrusion for up to N = 8 passes via route BC processing. The composite equation indicates that although low-angle grain boundaries provide the maximum strengthening up to N = 8 passes, the contribution from high-angle boundaries also increases with greater pass number. Alternatively, the evolution of boundary misorientation in as-ECAE microstructures and its effect on mechanical properties up to N = 3 passes is also understood by using a misorientation scaling factor within the original Hall-Petch equation