5th International Congress on 3D Materials Science (3DMS 2021): Tuesday Plenary
Program Organizers: Dorte Juul Jensen, Technical University of Denmark; Erica Lilleodden, Fraunhofer Insitute for Microstructure of Materials and Systems (IMWS); Scott Barnett, Northwestern University; Keith Knipling, Naval Research Laboratory; Matthew Miller, Cornell University; Akira Taniyama, The Japan Institute of Metals and Materials; Hiroyuki Toda, Kyushu University; Lei Zhang, Chinese Academy of Sciences
Tuesday 8:00 AM
June 29, 2021
Room: Virtual A
Location: Virtual
Session Chair: Dorte Juul Jensen, Technical University of Denmark
8:00 AM Introductory Comments
8:10 AM Plenary
Toward Dynamic 3D Visualization of Dislocations by Electron Tomography: Satoshi Hata1; Hikaru Saito1; Mitsuhiro Murayama2; 1Kyushu University; 2Virginia Tech; Pacific Northwest National Laboratory; Kyushu University
Observation of dislocation dynamics in three-dimensions (3D) is still challenging in the 3DMS research field. The authors’ group recently obtained a preliminary result of subsequently repeating in-situ specimen straining and electron tomography (ET) observation for a steel specimen in which a dislocation was interacting with a spheroidized cementite [1]. Although the observed magnitude of the dislocation movement was small, a few tens nm, the observation demonstrated the importance of 3D observation: the dislocation movement was recognized from some directions while not from the other directions. This different visibility of the dislocation movement is due to the geometrical relationship between the active slip plane and the viewing directions. In other words, a 3D imaging technique is indispensable for visualizing arbitral dislocation movements in such an in-situ straining and observation experiment.There are technical issues to be resolved toward a complete establishment of a 3D dislocation dynamics imaging method using ET. For example, diffraction alignment is an essential part of visualizing dislocations in ET. If we can predict how dislocations move in a specimen, we could keep the diffraction condition during the dislocation movement by precisely setting the crystallographic orientation regarding the loading direction. However, the aligned diffraction condition actually can change during the deformation of the specimen with applied stress. Therefore, the authors propose an alternative way to visualize 3D dislocation dynamics “without” keeping particular diffraction conditions during ET data acquisition. A procedure of the alternative way will be discussed.
9:10 AM Break