Altukhov O. Improvement of Technology of Workpieces Production with the Ultrafine Grained Structure by Severe Plastic Deformation Techniques

The object of research is the process of severe plastic deformation with simultaneous equal forming along the full volume of workpiece for plain strain conditions. The aim of research is the improvement of quality for workpieces with the ultrafine grained structure and increase in productivity for technological processes of severe plastic deformation on the basis of development, experimental studies and mathematical simulation of deformation techniques with shear strains intensification. Research techniques and instruments are numerical mathematical simulation, computer-aided design, and experimental techniques in a laboratory environment. Theoretical and practical results are theoretical models, computer-aided design techniques, and practical guidelines on improvement and perfection of technological processes for production of workpieces with the ultrafine grained structure by severe plastic deformation techniques. The prime novelty statement of this dissertation is in the general trends in distribution of stress-strain state in workpiece cross-sections depending upon the technological parameters, and dependencies for levels of plastic deformation accumulation along the workpiece cross-section upon the deformation stage for two schemes of reverse shearing processes. The level of introduction of the dissertation is reflected into practical guidelines on the choice of technological parameters of reverse shearing process for production of workpieces with the ultrafine grained structure. The efficient techniques and software have been developed for practical realization of technological process and die tooling design for production of workpieces with shear strains intensification. The application field is associated with production of components for aeronautical engineering, chemical industry equipment, and medical implants.