Abstract
The formation of multifold twins in nanocrystalline face-centered-cubic metals and alloys was frequently ascribed to a grain boundary (GB) mediated process. However, the geometrical requirement for the formation of multifold twins remains largely unclear. In this work, using combined in situ nanomechanical testing and atomistic simulation, we show that multifold twins can be generated through the migration of GBs associated with intersecting twin boundaries (TBs). We systematically evaluate a number of factors, including deformation geometry, loading condition, and coordinated deformation between GB and TB, that influence the underlying formation mechanisms. Such GB migration mediated formation of multifold twins exhibits a strong dependence on TB orientation (polarity) at GB-TB intersections and matrix orientation. Based on experimental observations, a general geometrical model is proposed to further reveal the intrinsic and extrinsic factors controlling the formation of multifold twins, which helps to establish a comprehensive map for the origin of multifold twins in nanocrystalline metals and also provides an accessible guidance for designing multifold twin structures in materials with high strength and good ductility.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
