Pile - up studies in dislocation - based single crystal gradient plasticity

/department of mechanical engineering Introduction In plastic deformations, which arise due to the motion of dislocations in crystalline microstructure, size effects cannot be neglected at a small scales of observation. Within each grain of a polycrystal, the grain boundaries act as natural obstacles to dislocation motion. Due to the stresses dislocations exert onto each other, dislocations will pileup against the grain boundaries as illustrated in Figure 1.