LAUSR

Abstract Anomalous basal stacking faults have frequently been observed inside 10 1 − 2 twins in deformed hcp metals. In this work, we report transmission electron microscopy observation of basal stacking faults inside 10 1 − 1 twins. These stacking faults present similar characteristics to those inside 10 1 − 2 twins. To reveal the formation mechanism, we performed atomistic simulations. The results show that the stacking faults are not mediated by partial dislocations. Lattice transformation analysis based on classical twinning theory shows that very large atomic shuffles (~ 0.16 nm) perpendicular to the twinning shear are required for twinning and responsible for the formation of these stacking faults.