Localization of macrodeformation in submicrocrystalline titanium

Abstract

A study of the deformation behavior of coarse-grained and submicrocrystalline commercially pure titanium has been carried out. The main specific feature of the behavior of the SMC material is the presence in the loading diagrams of a stage of prefracture, where the deformation occurs virtually without strengthening. At this stage, zones of localized plastic flow with different levels of deformation accumulation are observed. The zone with the maximum amplitude of deformation remains immobile fixed and marks the place of future destruction. The remaining regions of localized deformation move with a velocity that is the greater, the further the zone is located from the zone of fracture. It has been established that in the SMC titanium the local loss and the global loss of stability of plastic flow occur simultaneously. In the coarse-grained material the zone of future fracture is revealed even prior to the beginning of the formation of a macroscopic neck, i.e., the local loss of stability occurs comparatively early, although at the global level the material continues to be deformed quasihomogeneously. The results obtained can be used for correcting regimes of pressure treatment of nanostructured and submicrocrystalline materials.