Abstract
In the previous paper, dependence of the driving force of the deformation localization on the physical mechanisms of the elastic stiffness degradation caused by the plastic deformation, which is closely related to changes of ultrasonic wave velocities due to the plastic deformation, was examined in detail. Successively, the new model for ductile fracture initiation was proposed based on the new concept, i.e., ductile fracture initiation is caused by the jump of wave velocity along the intersected crossing line between two different stationary discontinuity bands characterized by vanishing velocity of an acceleration wave. The micro-crack nucleation caused by the jump of the velocity along intersected crossing line between the two discontinuity bands was verified theoretically by the shock wave theory and analyzed numerically using the theory of ultrasonic wave velocity under the plastic deformation proposed by the author. In the present paper, ductile fracture progress of FCC single crystals under plastic buckling is simulated using the finite element crystal plasticity model (FEPM) with built in proposed criteria, and then crystal orientation effect on plastic buckling progress of the single crystals is examined.
