抄録
Stress distribution and dislocation movements around a fatigue crack tip are analyzed by means of discrete dislocation dynamics (DDD). In this study, the 2-dimensional model taking into account the crack propagation is suggested in order to investigate the effect of crack growth on the dislocation behavior and the stress field near the crack tip. A lot of dislocations are distributed in the crack wake after several cycles as a result of the crack growth. The compressive stress in the vicinity of the crack tip during unloading is produced by the reaction force of the dislocations left in the crack wake and the positive dislocations which are piled up ahead in slip lines. The dislocation behavior and crack closure phenomenon near the growing fatigue crack tip can be simulated by the model suggested in the present study.
