Open AccessPhase-field crystal method investigated the dislocation annihilation and grain boundary migration in grain shrink process
Author(s) -
Li Shang-Jie,
Zheng Chen,
Yun Jiang-Juan,
Jing Zhang
Publication year - 2014
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.63.128101
Subject(s) - misorientation , materials science , grain boundary , climb , dislocation , grain boundary strengthening , condensed matter physics , dislocation creep , partial dislocations , grain boundary diffusion coefficient , crystallography , composite material , microstructure , physics , thermodynamics , chemistry
The phase-field crystal method is used to analysis the dislocation annihilation and grain boundary migration mechanism in the grain shrink process of the circular grain which has three different misorientations from the matrix grain. Results show that when the misorientation between the circular grain and the matrix grain is 17°, the structure of grain boundary is composed of dislocations whose cores is so near that can not find a single dislocation. This grain boundary can not be explained by the dislocation model. However the circular grain area decreases linearly with time, which is in good agreement with the classical boundary migration theory. When the misorientation is 4°, the grain boundary structure is composed of discrete dislocations. Dislocations climb along the radial dierction and the grain rotation occurs for the circular grain to adjust the space of dislocations in the process of circular grain shrinkage. Reactions may take place with the dislocatins becoming closer. For the misorientation of 10°, portion of the grain boundary is composed of discrete dislocations and portion of dislocations with cores overlapped. Dislocations climb along the radial direction and tangential motion occurs at the same time in the grain shrinkage process. The coupled motion lead to the dislocations becoming close and reacting with each other.