Void nucleation behavior of single-crystal high-purity iron specimens subjected to tensile deformation

Void nucleation plays an important role for determining local deformation properties of ductile materials. In this study, the void nucleation behavior of single-crystal iron was examined in tensile tests. Two micrometer-size single crystals having a different type of slip extracted from electrodeposited pure iron were used to investigate the fracture mechanics during tensile deformation. Scanning electron microscopy (SEM) and high voltage electron microscopy (HVEM) images verified the existence of only a single slip system in the smaller specimen (cross-sectional area A = 16µm2) and furthermore, no voids were observed. However, multiple slips and voids were observed in the larger specimen (A = 28µm2). These findings allowed us to reveal that multiple slips are a necessary criterion for void nucleation in single-crystal iron.