Year: 2026
Type: preprint
Abstract: Synchro-shear is the primary plastic deformation mechanism in Laves phases at elevated temperatures, mediated by synchro-Shockley partial dislocations-zonal dislocations that proceed via localized events such as kink-pair nucleation and propagation. Using atomistic simulations, we identified a novel slip mechanism in Laves phases, namely coupled synchro-shear slip, involving the synchronized glide of two synchro-Shockley partial dislocations on adjacent slip planes, leading to the formation of extrinsic stacking faults. High-resolution scanning transmission electron microscopy revealed the extended core structures consistent with coupled synchro-Shockley partial dislocations bounded by extrinsic stacking faults in C15 NbCr2 and their involvement in twinning. These results highlight the critical role of coupled synchro-shear slip in enabling phase transformations between Laves polytypes and in governing twinning behavior, providing new atomistic insight into the kinetic nature of plasticity in topologically close-packed intermetallic phases.
Source: arXiv (Cornell University)
Institutions: RWTH Aachen University, Ruhr University Bochum, Max-Planck-Institut für Nachhaltige Materialien, Fuyao University of Science and Technology, Centre National de la Recherche Scientifique, Arts et Métiers, Laboratoire d'Étude des Microstructures et de Mécanique des Matériaux, Université de Lorraine, Helmholtz-Zentrum Berlin für Materialien und Energie
Language: English
Subfield: Mechanical Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7212016745