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This article presents the results of the study of the joint effect of the processing conditions of the new composition of the Al-Zr system alloy by combined casting and rolling-extruding and two-stage annealing on the structure and properties of round bars used in the manufacture of heat-resistant wires. The research show patterns of changes in the properties, the specific electrical resistance of the bars, depending on different conditions of deformation and heat treatment of aluminum alloy with a content of 0.3% zirconium and 0.2% iron. The results of micro-X-ray spectral analysis and the granular structure of the samples before and after two-stage annealing confirming the stability of the structure after heating and preserving the strength of semi-finished products. Presented parameters of combined casting and rolling-extruding and two-stage annealing for the manufacture of rods from the studied alloy make it possible obtaining good combination of mechanical properties and electrical conductivity.

The results of computer simulation of the process of combined rolling-extruding of longish deformed semi-finished products from alloy 01417 are presented. A feature of the research is that continuously cast bars with a diameter of 12.5 mm obtained using an electromagnetic mold are used as a workpiece. This makes it possible to increase the manufacturability of processing and to obtain after rolling-extruding billets for drawing with a diameter of 5 mm with a large resource of plastic and strength properties. For this case the technological parameters and temperature and speed conditions of combined processing have not yet been studied, therefore, their analysis was performed using the Deform-3D software package. It has been revealed that the feasibility of the rolling-extruding process is significantly affected by the frequency of rotation of the rolls. Moreover, the process becomes unstable when the value of this parameter is 4 rpm, which can be explained by insufficient degrees of deformation during rolling, and consequently by the small value of the active friction forces acting on the contact surface of the metal with the rolls. As a result of this, the processing temperature conditions also change, which is also demonstrated using the developed computer model. As a result, it was found that for the stable course of the combined rolling-extruding process at the CRE-200 unit of a continuously cast billet with a diameter of 12.5 mm from alloy 01417 at a heating temperature of the billet of 550 °C and a tool of 200 °C, degree of deformation during rolling 44% and drawing ratio during extruding 18.6 the frequency of rotation of the rolls should be at least 8 rpm. The simulation data used during the implementation of the process at the combined processing unit CRE-200, the results of which made it possible to finally obtain electrotechnical wire with a diameter of 0.5 mm from 01417 alloy that meets the requirements of TS 1-809-63-2018.

The paper presents the results of studies of the structure and properties of a wire with a diameter of 0.5 mm from an alloy of the Al-REM system with a rare-earth metal content of 7-9%. Wire obtained as a result of the implementation of the technology of its manufacture using the methods of casting into an electromagnetic mold (EMM), continuous extruding and drawing.The rheological properties of the metal of continuously cast round billets from the experimental alloy obtained using an electromagnetic mold are determined. The modeling and analytical assessment of the possibility of carrying out the process of combined rolling-extruding (CRE) of such billets in a closed boxtype roll groove of a continuous extruding unit are carried out. The features of metal shaping have been studied. The temperature-speed and technological parameters was found at which the CRE process can be carried out in a stable mode of operation. Data have been obtained for the forces acting on the die and rolls and the moments on the rolls during rolling-extruding.The results of experimental studies of the process of obtaining longish deformed semi-finished products from an experimental alloy on the laboratory unit CRE-200 and the pilot plant unit CRE-400 are presented. The structure of the metal has been studied; data on the ultimate tensile strength, yield strength, relative elongation, and electrical resistivity of hot-extruded rods and wires in cold-worked and annealed states have been obtained.It was found that the proposed processing modes make it possible to obtain by the method of combined rolling-extruding rods with a diameter of 9 mm in industrial conditions from longish billets with a diameter of 18 mm, cast by means of EMM. Wire in a cold-worked and annealed state with a diameter of 0.5 obtained by drawing from the rods with a diameter of 9 mm from an experimental alloy of the Al-REM system containing 7-9 rare earth metals with the required physical and mechanical properties.

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