Investigation of localized plastic shear mechanisms under dynamic loading

• Main Authors: Sokovikov, M., Chudinov, V., Oborin, V., Uvarov, S., Naimark, O.
• Format: Conference Proceeding
• Language: English
• Subjects: Ballistic impact tests; Deformation mechanisms; Dislocations; Ejection; High strength steels; Localization; Perforation; Plastic deformation; Plastic flow; Projectiles; Stability; Substructures; Subsystems
• ISSN: 0094-243X; 1551-7616
• DOI: 10.1063/1.5084429

Experimental and theoretical studies on the mechanisms of plastic deformation localization under dynamic loading have been carried out. Experiments on the dynamic loading of specimens were performed on the split Hopkinson bar and on the ballistic system designed for target perforation. To study localized shear under high-speed loading, we used specimens of a specific shape developed for the performance of these particular experiments. The localization of plastic strain at high loading speeds was also investigated in the ballistic tests on the perforation of targets under the impact of a cylindrical projectile made of high-strength steel, which is accompanied by the formation and ejection of the plug. The mechanisms are associated with the collective effects in the ensemble of microdefects in spatially localized regions. In-situ infrared scanning of the instability zone followed by the study of the dislocation substructure provided supporting evidence for the assumption that the above processes play a significant role in the defect subsystem of the material during the development of localized plastic flow. Modeling of localization of plastic deformation is carried out using the equations that relate the non-equilibrium transitions to the mechanisms of structural relaxation and plastic flow.