Siberian Federal University, Krasnoyarsk, Russia:

V. N. Baranov, Assistant Professor, Director of Institute of Non-Ferrous Metals and Materials Science
S. B. Sidelnikov, Professor, Head of a Chair “Metal Forming”, e-mail: sbs270359@yandex.ru
A. I. Bezrukikh, Assistant Professor of a Chair “Metal Forming”

JSC “RUSAL” Bratsk Aluminium Smelter, Bratsk, Russia:
E. Yu. Zenkin, Managing Director

Our paper shows the research results of thermodeformation machining of flat ingots made of experimental aluminium alloys, containing magnesium, scandium, rare-earth and transition metals. Relevance of the work aimed at creating the new Al – Mg system alloys, alloyed by scandium, and technologies for obtaining deformed semi-finished products from them using metal forming operations are shown. Regimes of hot and cold sheet rolling for obtaining strips with thickness 1–3 mm from these alloys were calculated and experimentally tested. Experimental research included the following steps: preparation of flat slabs with dimensions 28150300 mm for rolling; hot rolling at the temperature of 450 ^оC with total draw ratio about 6; cold rolling with total draw ratio about 5; annealing of cold-deformed semi-finished products at the temperature of 350 ^оC within 3 hours; argon-arc welding of the obtained strips along and across the direction of deformation; intergranular corrosion test; evaluation of mechanical properties of the samples. As a result, the nature and degree of corrosion destruction were studied and mechanical properties of deformed, annealed and welded semi-finished products from experimental alloys were determined. It is established that they have a high level of strength and plastic properties of the metal along, across and at an angle 45o relative to the direction of rolling. So tensile strength reaches the value 500–520 MPa for deformed samples, yield strength of metal 435–470 MPa, relative elongation 4.8–6.7%, and for annealed samples the values of the relative elongation increase and can reach 14.0–14.5% at the sufficiently high yield strength 357–369 MPa. Tests for intergranular corrosion of samples after welding showed high corrosion resistance of welded joints. The strength of the welded seam is 0.75–0.85 of the strength of the base metal. The results of research can be recommended for the development of technology for the manufacture of parts from flat products, including welded joints.

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