Orlov D. Theory developing and design of twist extrusion technology for titanium and copper

The subject of these investigations is twist extrusion process. Thesis is devoted to theory developing and design of twist extrusion technology for titanium and copper. Theoretical investigations of the energy-power parameters and degree of accumulated strain are done by variational method using computer. The experimental investigations of plastic flow done by physical modeling, energy-power parameters by strain measurement. Structure of the deformed materials is investigated by both optical and electron microscopy. Mechanical properties is obtained by microhardness measurement and in the elongations tests. It is shown in the work that during the twist extrusion metals flow basically contains from two components. The first one satisfy to the trajectories which describe particles "frozen" into cross-section moving along the twist channel. The second one corresponds to the moving of the particles inside the cross-section. It is obtained relations for determination of value and distribution of accumulatedstrain and energy-power parameters of the process. The relations taking into account the peculiarities of metals flow. It is determined basic control parameters of the twist extrusion and investigated character of their influence on the workpieces quality indexes. Practical using have designed software called "Twist extrusion". The software allows calculate basic parameters of the twist extrusion. It is developed technology tools, twist extrusion technology and basics of technology of high strain accumulation in workpieces from copper M1 and M0 and titanium VT1-0. It is obtained bulks of copper M1 and M0 and titanium VT1-0 with high mechanical properties. The results and recommendations of this work are used during designing technology of ultra-fine grained structured Ti and Cu obtaining in DonPhTI and DonNTU. The obtained specimens of Ti and Cu are transferred to the different institutes in Ukraine, Russia and other countries.