Investigation of rolling modes, structure, and properties of aluminum-magnesium alloy plates with a reduced scandium content

Investigations of the rolling modes of plates from an experimental aluminum-magnesium alloy with a scandium content of 0.10-0.11 wt.%, corresponding to the chemical composition of the 1580 alloy, were carried out in laboratory and industrial conditions. It has been found that alloying of this material with scandium within the indicated limits leads to a significant grain refinement in the cast ingot and an increase in the strength properties of deformed semi-finished products. Based on the results of physical modeling of the rolling process, rational reduction modes are proposed, which made it possible to obtain deformed semi-finished products with the required level of mechanical properties. Based on the results of physical and computer modeling of the rolling process, rational reduction modes are proposed for pilot studies, which made it possible to obtain deformed semi-finished products with the required level of mechanical properties. At the same time, the power parameters of rolling did not exceed the allowable values of the force and rolling moment for the QUARTO 2800 rolling mill. To assess the formation patterns of the metal structure necessary to obtain high-quality plates, a metallographic analysis of the structure of cast and deformed semi-finished products from an experimental alloy was carried out. The results were used to test the reduction modes during sheet rolling and to adjust the casting parameters of experimental ingots. Annealing has practically no effect on the level of mechanical properties of plates obtained under production conditions in a hot-deformed state, while the ultimate tensile strength in the longitudinal direction is 388-389 MPa, the yield strength is 245-247 MPa, and the elongation to failure is 18.0-18.8%. After cold rolling, the plates have the following mechanical properties: ultimate tensile strength 413-414 MPa, yield strength 386-372 MPa, and elongation to failure 5.2-6.6%. Based on the results of the research, recommendations were formulated for the development and implementation of an industrial technology for rolling plates from alloy 1580 with a thickness of 31.5-45 mm from ingots with a thickness of 300-450 mm.