We apply the heat jet approach to realize atomic simulations at finite temperature for a Frenkel–Kontorova chain with moving dislocation. This approach accurately and efficiently controls the system temperature by in...We apply the heat jet approach to realize atomic simulations at finite temperature for a Frenkel–Kontorova chain with moving dislocation. This approach accurately and efficiently controls the system temperature by injecting thermal fluctuations into the system from its boundaries, without modifying the governing equations for the interior domain. This guarantees the dislocation propagating in the atomic chain without nonphysical damping or deformation. In contrast to the non-equilibrium Nosé–Hoover heat bath, the heat jet approach efficiently suppresses boundary reflections while the moving dislocation and interior waves pass across the boundary. The system automatically returns back to the equilibrium state after all non-thermal motions pass away. We further apply this approach to study the impact of periodic potential and temperature field on the velocity of moving dislocation.展开更多
This paper attempts to investigate the problem for the interaction between a uniformly moving screw dislocation and interface rigid lines in two dissimilar.anisotropic. materials. Integrating Riemann-Schwarz＇s symmet...This paper attempts to investigate the problem for the interaction between a uniformly moving screw dislocation and interface rigid lines in two dissimilar.anisotropic. materials. Integrating Riemann-Schwarz＇s symmetry principle with the analysis singularity of complex functions, we present the general elastic solutions of this problem and the closed form solutions for interfaces containing one and two rigid lines. The expressions of stress intensity factors, at the rigid line tips and image force acting on moving dislocation are derived explicitly. The results show that dislocation velocity has an antishielding effect on the rigid line tip and a larger dislocation velocity leads to the equilibrium position of dislocation closing with the rigid line. The presented solutions contain previously known results as the special cases.展开更多
The onset of dynamic friction plays an important role in the study of sliding interfaces.Previously,the sliding precursors in the form of crack-like defects have been detected in experiments and their strain fields ha...The onset of dynamic friction plays an important role in the study of sliding interfaces.Previously,the sliding precursors in the form of crack-like defects have been detected in experiments and their strain fields have been measured to be comparable to those of moving cracks.In the present work,we considered the dynamics of sliding precursors by solving the elastic problem due to a moving dislocation in a half-plane and the transient emission of a dislocation at the edge.It has been found that both the strain field of a moving dislocation and the spatiotemporal evolution agree well with those of a sliding precursor detected in experiments.The results may cast new light to the dynamics of sliding onset.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11890681,11832001,and 11988102)。
文摘We apply the heat jet approach to realize atomic simulations at finite temperature for a Frenkel–Kontorova chain with moving dislocation. This approach accurately and efficiently controls the system temperature by injecting thermal fluctuations into the system from its boundaries, without modifying the governing equations for the interior domain. This guarantees the dislocation propagating in the atomic chain without nonphysical damping or deformation. In contrast to the non-equilibrium Nosé–Hoover heat bath, the heat jet approach efficiently suppresses boundary reflections while the moving dislocation and interior waves pass across the boundary. The system automatically returns back to the equilibrium state after all non-thermal motions pass away. We further apply this approach to study the impact of periodic potential and temperature field on the velocity of moving dislocation.
基金the National Natural Science Foundation of China(No.10472030)
文摘This paper attempts to investigate the problem for the interaction between a uniformly moving screw dislocation and interface rigid lines in two dissimilar.anisotropic. materials. Integrating Riemann-Schwarz＇s symmetry principle with the analysis singularity of complex functions, we present the general elastic solutions of this problem and the closed form solutions for interfaces containing one and two rigid lines. The expressions of stress intensity factors, at the rigid line tips and image force acting on moving dislocation are derived explicitly. The results show that dislocation velocity has an antishielding effect on the rigid line tip and a larger dislocation velocity leads to the equilibrium position of dislocation closing with the rigid line. The presented solutions contain previously known results as the special cases.
基金The authors are grateful for the support by the National Natural Science Foundation of China under Grant Nos.1177220,12021002 and 11572216.
文摘The onset of dynamic friction plays an important role in the study of sliding interfaces.Previously,the sliding precursors in the form of crack-like defects have been detected in experiments and their strain fields have been measured to be comparable to those of moving cracks.In the present work,we considered the dynamics of sliding precursors by solving the elastic problem due to a moving dislocation in a half-plane and the transient emission of a dislocation at the edge.It has been found that both the strain field of a moving dislocation and the spatiotemporal evolution agree well with those of a sliding precursor detected in experiments.The results may cast new light to the dynamics of sliding onset.
