The stacking fault energy of Fe-18Mn-0.6C-1.5%Al twinning-induced plasticity steel was measured using weak-beam dark-field imaging of dissociated dislocations observed in transmission electron microscopy. The stacking fault energy was found to be 30mJ/m2. A relatively wide scatter was observed in the experimentally measured partial dislocation separation of screw dislocations. It was argued that the anomalously wide partial dislocation separation was due to the interaction of point-defect pairs involving interstitial C atoms with the strain field of the partial dislocations. Internal friction experiments were carried out to detect the presence of point-defect pairs that might affect the dislocation separation, and a clear Finkelshtein–Rosin peak related to point-defect pairs involving interstitial C atoms was observed in the internal friction spectrum.

On the Stacking Fault Energy of Fe-18 Pct Mn-0.6 Pct C-1.5 Pct Al Twinning-Induced Plasticity Steel. J.Kim, B.C.De Cooman: Metallurgical and Materials Transactions A, 2011, 42[4], 932-6