摘要
Deformation twinning is evidenced by transmission electron microscopy examinations in electrodeposited nanocrystalline （nc） Ni with mean grain size 25nm upon cryogenic rolling. Two twinning mechanisms are confirmed to operate in nc grains, i.e. heterogeneous formation via emission of partial dislocations from the grain boundary and homogeneous nucleation through dynamic overlapping of stacking faults, with the former being determined as the most proficient. Deformation twinning in nc Ni may be well interpreted in terms of molecular dynamics simulation based on generalized planar fault energy curves.
Deformation twinning is evidenced by transmission electron microscopy examinations in electrodeposited nanocrystalline （nc） Ni with mean grain size 25nm upon cryogenic rolling. Two twinning mechanisms are confirmed to operate in nc grains, i.e. heterogeneous formation via emission of partial dislocations from the grain boundary and homogeneous nucleation through dynamic overlapping of stacking faults, with the former being determined as the most proficient. Deformation twinning in nc Ni may be well interpreted in terms of molecular dynamics simulation based on generalized planar fault energy curves.
基金
Supported by the National Natural Science Foundation of China under Grant Nos 50471086, 50571110, 10472117, and 50021101, the National Key Basic Research and Development Programme of China under Grant. No 2004CB619305, the Knowledge Innovation Project of Chinese Academy of Sciences under Grant No KJCX2-SW-L2, and the National Center for Nanoscience and Technology of China.
